WorldWideScience

Sample records for machine tool vibration

  1. An Investigation of Vibration Reducing on a Machine Tool

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    In order to reduce the vibration on a machine tool, more orthogonal experiment schemes have been designed, which are based on the steel balls vibration reducing principle. After experiments the optimal reducing vibration scheme was determined. This kind of vibration reducing scheme is used in steel balls vibration absorber, which can be used to reduce vibration magnitudes of a machine tools under the working conditions, whereby improving machining precision. The suggested experiment method is of useful reference in reducing vibrations on other machine tools too.

  2. Experimental investigation of active machine tool vibration control

    Science.gov (United States)

    Rojas, J.; Liang, Chen; Geng, Zheng J.

    1996-05-01

    The successful vibration reduction of machine tools during machining process can improve productivity, increase quality, and reduce tool wear. This paper will present our initial investigation in the application of smart material technologies in machine tool vibration control using magnetostrictive actuators and electrorheological elastomer dampers on an industrial Sheldon horizontal lathe. The dynamics of the machining process are first studied, which reveals the complexity in the machine tool vibration response and the challenge to the active control techniques. The active control experiment shows encouraging results. The use of electrorheological elastomer damping device for active/passive vibration control provides significant vibration reduction in the high frequency range and great improvement in the workpiece surface finishing. The research presented in this paper demonstrates that the combination of active and active/passive vibration control techniques is very promising for successful machine tool vibration control.

  3. Real-Time Compensation of Chatter Vibration in Machine Tools

    Directory of Open Access Journals (Sweden)

    Dong-Hoon Kim

    2013-05-01

    Full Text Available The chatter vibration stands for a sudden relative vibration appeared between a material and a tool while processing with a machine. This vibration is a factor that seriously affects the quality of processed materials as well as being a factor which causes serious damages to the tool and the machine. This study is related to the detection and compensation of chatter vibration that can compensate chatter vibration faster and produce processed goods with more precision by autonomous compensation. The above-mentioned chatter vibration compensator includes the chatter vibration sensor and the chatter compensator that estimates the compensation value according to the sensor detecting the chatter vibration of machine tool and the chatter vibration detected from the sensor while having a feature of being organized by interlocking with the machine tool controller.

  4. Robust Control of Machine-Tool Vibration in a Lathe

    OpenAIRE

    Claesson, Ingvar; Håkansson, Lars; Lagö, Thomas L.

    1999-01-01

    In the turning operation the relative dynamic motion between cutting tool and workpiece, or vibration, is a frequent problem, which affects the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. These problems can be reduced substantially by active control of the machine-tool vibration. Adaptive fe...

  5. Active Control of Machine-Tool Vibration in a Lathe

    OpenAIRE

    Claesson, Ingvar; Håkansson, Lars

    1997-01-01

    In the turning operation the relative dynamic motion between cutting tool and workpiece, or vibration is a frequent problem, which affects the result of the machining, in particular the surface finish. The tool life is also influenced by the vibrations. When the working environment is considered, noise is frequently introduced by dynamic motion between the cutting tool and the workpiece. By proper machine design, e.g. improved stiffness of the machine structure, the problem of relative dynami...

  6. In-process machine tool vibration cancellation using PMN actuators

    Science.gov (United States)

    Eshete, Zelalem; Zhang, Guangming

    1996-12-01

    At present, the machine tool technology in the US is not in the state-of-the-art of leading international competitors. Conventional machine tools under use are being pushed into their machining accuracy limits. There is a pressing need calling for revitalizing the machine tool industry. This paper presents, a mechatronic system developed for reducing tool vibration during machining. It consists of electrical and mechanical components, and is realized by placing electrically driven electrostrictive actuators in a specially designed tool post mechanical structure. The linear neural network controller, namely, digital filters, are implemented using a signal processing board. The experimental investigation is conducted in two stages. In the first stage, a test bed is established to use an electro-magnetic shaker to resemble the excitation of cutting force acting on the tool. In the second stage, experiments were conducted using a lathe on the shop floor. In-process vibration cancellation was observed. In the laboratory experiment, a percent reduction in the 90 percent was possible using a feedforward scheme. The improvement in surface roughness during the turning operation was confirmed from measurements of surface roughness profiles.

  7. Adaptive Control of Machine-Tool Vibration Based on an Active Tool Holder Shank with an Embedded Piezo Ceramic Actuator

    OpenAIRE

    Pettersson, Linus; Håkansson, Lars; Claesson, Ingvar; Olsson, Sven

    2001-01-01

    In the turning operation chatter or vibration is a common problem affecting the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. These problems can be reduced by active control of machine-tool vibration. However, machine-tool vibration control systems are usually not applicable to a general lathe...

  8. Adaptive Active Control of Machine-Tool Vibration In a Lathe

    OpenAIRE

    Claesson, Ingvar; Håkansson, Lars

    1998-01-01

    In the turning operation the relative dynamic motion between cutting tool and workpiece, or vibration, is a frequent problem, which affects the result of the machining, and in particular, the surface finish. Tool life is also influenced by vibration. Noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. With proper machine design, i.e. improved stiffness of the machine structure, the problem of relative dynamic motion betw...

  9. Analysis on machine tool systems using spindle vibration monitoring for automatic tool changer

    Directory of Open Access Journals (Sweden)

    Shang-Liang Chen

    2015-12-01

    Full Text Available Recently, the intelligent systems of technology have become one of the major items in the development of machine tools. One crucial technology is the machinery status monitoring function, which is required for abnormal warnings and the improvement of cutting efficiency. During processing, the mobility act of the spindle unit determines the most frequent and important part such as automatic tool changer. The vibration detection system includes the development of hardware and software, such as vibration meter, signal acquisition card, data processing platform, and machine control program. Meanwhile, based on the difference between the mechanical configuration and the desired characteristics, it is difficult for a vibration detection system to directly choose the commercially available kits. For this reason, it was also selected as an item for self-development research, along with the exploration of a significant parametric study that is sufficient to represent the machine characteristics and states. However, we also launched the development of functional parts of the system simultaneously. Finally, we entered the conditions and the parameters generated from both the states and the characteristics into the developed system to verify its feasibility.

  10. Optimization of Surface Finish in Turning Operation by Considering the Machine Tool Vibration using Taguchi Method

    Directory of Open Access Journals (Sweden)

    Muhammad Munawar

    2012-01-01

    Full Text Available Optimization of surface roughness has been one of the primary objectives in most of the machining operations. Poor control on the desired surface roughness generates non conforming parts and results into increase in cost and loss of productivity due to rework or scrap. Surface roughness value is a result of several process variables among which machine tool condition is one of the significant variables. In this study, experimentation was carried out to investigate the effect of machine tool condition on surface roughness. Variable used to represent machine tool\\'s condition was vibration amplitude. Input parameters used, besides vibration amplitude, were feed rate and insert nose radius. Cutting speed and depth of cut were kept constant. Based on Taguchi orthogonal array, a series of experimentation was designed and performed on AISI 1040 carbon steel bar at default and induced machine tool\\'s vibration amplitudes. ANOVA (Analysis of Variance, revealed that vibration amplitude and feed rate had moderate effect on the surface roughness and insert nose radius had the highest significant effect on the surface roughness. It was also found that a machine tool with low vibration amplitude produced better surface roughness. Insert with larger nose radius produced better surface roughness at low feed rate.

  11. An Approach to the Classification of Cutting Vibration on Machine Tools

    Directory of Open Access Journals (Sweden)

    Jeng-Fung Chen

    2016-02-01

    Full Text Available Predictions of cutting vibrations are necessary for improving the operational efficiency, product quality, and safety in the machining process, since the vibration is the main factor for resulting in machine faults. “Cutting vibration” may be caused by setting incorrect parameters before machining is commenced and may affect the precision of the machined work piece. This raises the need to have an effective model that can be used to predict cutting vibrations. In this study, an artificial neural network (ANN model to forecast and classify the cutting vibration of the intelligent machine tool is presented. The factors that may cause cutting vibrations is firstly identified and a dataset for the research purpose is constructed. Then, the applicability of the model is illustrated. Based on the results in the comparative analysis, the artificial neural network approach performed better than the others. Because the vibration can be forecasted and classified, the product quality can be managed. This work may help new workers to avoid operating machine tools incorrectly, and hence can decrease manufacturing costs. It is expected that this study can enhance the performance of machine tools in metalworking sectors.

  12. Active Control of Machine-Tool Vibration in a CNC Lathe Based on an Active Tool Holder Shank with Embedded Piezo Ceramic Actuators

    OpenAIRE

    Pettersson, Linus; Håkansson, Lars; Claesson, Ingvar; Olsson, Sven

    2001-01-01

    In the turning operation chatter or vibration is a frequent problem affecting the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. These problems can be reduced by active control of machine-tool vibration. However, machine-tool vibration control systems are usually not applicable to a general lat...

  13. Modeling of Tool Wear in Vibration Assisted Nano Impact-Machining by Loose Abrasives

    Directory of Open Access Journals (Sweden)

    Sagil James

    2014-01-01

    Full Text Available Vibration assisted nano impact-machining by loose abrasives (VANILA is a novel nanomachining process that combines the principles of vibration assisted abrasive machining and tip-based nanomachining, to perform target specific nanoabrasive machining of hard and brittle materials. An atomic force microscope (AFM is used as a platform in this process wherein nanoabrasives, injected in slurry between the workpiece and the vibrating AFM probe which is the tool, impact the workpiece and cause nanoscale material removal. The VANILA process are conducted such that the tool tip does not directly contact the workpiece. The level of precision and quality of the machined features in a nanomachining process is contingent on the tool wear which is inevitable. Initial experimental studies have demonstrated reduced tool wear in the VANILA process as compared to indentation process in which the tool directly contacts the workpiece surface. In this study, the tool wear rate during the VANILA process is analytically modeled considering impacts of abrasive grains on the tool tip surface. Experiments are conducted using several tools in order to validate the predictions of the theoretical model. It is seen that the model is capable of accurately predicting the tool wear rate within 10% deviation.

  14. The Axial Nonlinear Vibration Analysis of Ball-screw about Machine Tool Feeding System

    Institute of Scientific and Technical Information of China (English)

    ZENG Hao-ran; LIU Nian-cong; YANG Jia-rui; CHEN Jian-long; GENG Wei-tao

    2016-01-01

    The forced state of the ball⁃screw of machine tool feeding system is analyzed. The ball⁃screw is simplified as Timoshenko beam and the differential equation of motion for the ball⁃screw is built. To obtain the axial vibration equation, the differential equation of motion is simplified using the assumed mode method. Axial vibration equation is in form of Duffing equation and has the characteristics of nonlinearity. The numerical simulation of Duffing equation is proceeded by MATLAB/Simulink. The effect of screw length, exciting force and damping coefficient are researched, and the axial vibration phase track diagram and Poincare section are obtained. The stability and period of the axial vibration are analyzed. The limit cycle of phase track diagram is enclosed. Axial vibration has two type⁃center singularity distributions on both sides of the origin. The singularity attracts vibration to reach a stable state, and Poincare section shows that axial vibration appears chaotic motion and quasi periodic motion or periodic motion. Singularity position changes with the vibration system parameters, while the distribution doesn′t change. The period of the vibration is enhanced with increasing frequency and damping coefficient. Test of the feeding system ball⁃screw axial vibration exists chaos movement. This paper provides a certain theoretical basis for the dynamic characteristic analysis of machine feeding system ball⁃screw and optimization of structural parameters.

  15. Development of Dual-Axis MEMS Accelerometers for Machine Tools Vibration Monitoring

    Directory of Open Access Journals (Sweden)

    Chih-Yung Huang

    2016-07-01

    Full Text Available With the development of intelligent machine tools, monitoring the vibration by the accelerometer is an important issue. Accelerometers used for measuring vibration signals during milling processes require the characteristics of high sensitivity, high resolution, and high bandwidth. A commonly used accelerometer is the lead zirconate titanate (PZT type; however, integrating it into intelligent modules is excessively expensive and difficult. Therefore, the micro electro mechanical systems (MEMS accelerometer is an alternative with the advantages of lower price and superior integration. In the present study, we integrated two MEMS accelerometer chips into a low-pass filter and housing to develop a low-cost dual-axis accelerometer with a bandwidth of 5 kHz and a full scale range of ±50 g for measuring machine tool vibration. In addition, a platform for measuring the linearity, cross-axis sensitivity and frequency response of the MEMS accelerometer by using the back-to-back calibration method was also developed. Finally, cutting experiments with steady and chatter cutting were performed to verify the results of comparing the MEMS accelerometer with the PZT accelerometer in the time and frequency domains. The results demonstrated that the dual-axis MEMS accelerometer is suitable for monitoring the vibration of machine tools at low cost.

  16. DIAGNOSTICS OF WORKPIECE SURFACE CONDITION BASED ON CUTTING TOOL VIBRATIONS DURING MACHINING

    Directory of Open Access Journals (Sweden)

    Jerzy Józwik

    2015-05-01

    Full Text Available The paper presents functional relationships between surface geometry parameters, feed and vibrations level in the radial direction of the workpiece. Time characteristics of the acceleration of cutting tool vibration registered during C45 steel and stainless steel machining for separate axes (X, Y, Z were presented as a function of feedrate f. During the tests surface geometric accuracy assessment was performed and 3D surface roughness parameters were determined. The Sz parameter was selected for the analysis, which was then collated with RMS vibration acceleration and feedrate f. The Sz parameter indirectly provides information on peak to valley height and is characterised by high generalising potential i.e. it is highly correlated to other surface and volume parameters of surface roughness. Test results presented in this paper may constitute a valuable source of information considering the influence of vibrations on geometric accuracy of elements for engineers designing technological processes.

  17. An Approach to the Classification of Cutting Vibration on Machine Tools

    OpenAIRE

    Jeng-Fung Chen; Shih-Kuei Lo; Quang Hung Do

    2016-01-01

    Predictions of cutting vibrations are necessary for improving the operational efficiency, product quality, and safety in the machining process, since the vibration is the main factor for resulting in machine faults. “Cutting vibration” may be caused by setting incorrect parameters before machining is commenced and may affect the precision of the machined work piece. This raises the need to have an effective model that can be used to predict cutting vibrations. In this study, an artificial neu...

  18. Machine tool structures

    CERN Document Server

    Koenigsberger, F

    1970-01-01

    Machine Tool Structures, Volume 1 deals with fundamental theories and calculation methods for machine tool structures. Experimental investigations into stiffness are discussed, along with the application of the results to the design of machine tool structures. Topics covered range from static and dynamic stiffness to chatter in metal cutting, stability in machine tools, and deformations of machine tool structures. This volume is divided into three sections and opens with a discussion on stiffness specifications and the effect of stiffness on the behavior of the machine under forced vibration c

  19. Vibration suppression in multi-tool ultrasonic machining to multi-external and parametric excitations

    Institute of Scientific and Technical Information of China (English)

    M.M.Kamel; W.A.A.El-Ganaini; Y.S.Hamed

    2009-01-01

    Ultrasonic machining (USM) is of particular interest for the machining of non-conductive, brittle mate-rials such as engineering ceramics, In this paper, a multi-tool technique is used in USM to reduce the vibration in the tool holder and have reasonable amplitude for the tools. This can be done via dynamic absorbers. The coupling of four non-linear oscillators of the tool holder and tools representing ultrasonic cutting process are investigated. This leads to a four-degree-of-freedom system subjected to multi-external and multi-parametric excitation forces. The aim of this work is to control the tool holder behavior at simultaneous pri-mary, sub-harmonic and internal resonance condition. Mul-tiple scale perturbation method is used to obtain the solution up to the second order approximations. The different reso-nance cases are reported and studied numerically. The stabil-ity of the system is investigated by using both phase-plane and frequency response techniques. The effects of the differ-ent parameters of the tools on the system behavior are studied numerically. Comparison with the available published work is reported.

  20. Analysis of the effect of ultrasonic vibrations on the performance of micro-electrical discharge machining of A2 tool steel

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    The application of ultrasonic vibrations to a workpiece or tool is a novel hybrid approach in micro-electrical discharge machining. The advantages of this method include effective flushing out of debris, higher machining efficiency and lesser short-circuits during machining. This paper presents...... effective at higher machining depths for achieving stable machining conditions. Regression equations were developed for MRR and TWR with capacitance, ultrasonic vibration factor, feed rate and machining time....

  1. Chatter and machine tools

    CERN Document Server

    Stone, Brian

    2014-01-01

    Focussing on occurrences of unstable vibrations, or Chatter, in machine tools, this book gives important insights into how to eliminate chatter with associated improvements in product quality, surface finish and tool wear. Covering a wide range of machining processes, including turning, drilling, milling and grinding, the author uses his research expertise and practical knowledge of vibration problems to provide solutions supported by experimental evidence of their effectiveness. In addition, this book contains links to supplementary animation programs that help readers to visualise the ideas detailed in the text. Advancing knowledge in chatter avoidance and suggesting areas for new innovations, Chatter and Machine Tools serves as a handbook for those desiring to achieve significant reductions in noise, longer tool and grinding wheel life and improved product finish.

  2. Analysis of the effect of ultrasonic vibrations on the performance of micro-electrical discharge machining of A2 tool steel

    DEFF Research Database (Denmark)

    Puthumana, Govindan

    2016-01-01

    The application of ultrasonic vibrations to a workpiece or tool is a novel hybrid approach in micro-electrical discharge machining. The advantages of this method include effective flushing out of debris, higher machining efficiency and lesser short-circuits during machining. This paper presents...... a systematic analysis of the influence of kinetic effects of the ultrasonic vibrations on the material removal rate (MRR) and tool electrode wear rate (TWR). The tool wear ratio was estimated for the process at all processing conditions. The maximum variation in tool wear ratio is observed to be 82%. Therefore......, MRR and TWR were independently analyzed by using three scientific tools: i) AOM plots, ii) interaction plots and iii) three-dimensional scatter plots. The increase in MRR is 47% corresponding to an increase in the maximum power of vibrations by 30%. The ultrasonic vibrations are found to be very...

  3. Method for vibration response simulation and sensor placement optimization of a machine tool spindle system with a bearing defect.

    Science.gov (United States)

    Cao, Hongrui; Niu, Linkai; He, Zhengjia

    2012-01-01

    Bearing defects are one of the most important mechanical sources for vibration and noise generation in machine tool spindles. In this study, an integrated finite element (FE) model is proposed to predict the vibration responses of a spindle bearing system with localized bearing defects and then the sensor placement for better detection of bearing faults is optimized. A nonlinear bearing model is developed based on Jones' bearing theory, while the drawbar, shaft and housing are modeled as Timoshenko's beam. The bearing model is then integrated into the FE model of drawbar/shaft/housing by assembling equations of motion. The Newmark time integration method is used to solve the vibration responses numerically. The FE model of the spindle-bearing system was verified by conducting dynamic tests. Then, the localized bearing defects were modeled and vibration responses generated by the outer ring defect were simulated as an illustration. The optimization scheme of the sensor placement was carried out on the test spindle. The results proved that, the optimal sensor placement depends on the vibration modes under different boundary conditions and the transfer path between the excitation and the response.

  4. Active Control of Machine Tool Chatter

    OpenAIRE

    Håkansson, Lars; Claesson, Ingvar; Lagö, Thomas L.

    1999-01-01

    In the turning operation chatter or vibration is a frequent problem, which affects the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. By proper machine design, e.g. improved stiffness of the machine structure, the problem of relative dynamic motion between cutting tool and workpiece may be part...

  5. Prediction of Machine Tool Condition Using Support Vector Machine

    Science.gov (United States)

    Wang, Peigong; Meng, Qingfeng; Zhao, Jian; Li, Junjie; Wang, Xiufeng

    2011-07-01

    Condition monitoring and predicting of CNC machine tools are investigated in this paper. Considering the CNC machine tools are often small numbers of samples, a condition predicting method for CNC machine tools based on support vector machines (SVMs) is proposed, then one-step and multi-step condition prediction models are constructed. The support vector machines prediction models are used to predict the trends of working condition of a certain type of CNC worm wheel and gear grinding machine by applying sequence data of vibration signal, which is collected during machine processing. And the relationship between different eigenvalue in CNC vibration signal and machining quality is discussed. The test result shows that the trend of vibration signal Peak-to-peak value in surface normal direction is most relevant to the trend of surface roughness value. In trends prediction of working condition, support vector machine has higher prediction accuracy both in the short term ('One-step') and long term (multi-step) prediction compared to autoregressive (AR) model and the RBF neural network. Experimental results show that it is feasible to apply support vector machine to CNC machine tool condition prediction.

  6. Machine Tool Software

    Science.gov (United States)

    1988-01-01

    A NASA-developed software package has played a part in technical education of students who major in Mechanical Engineering Technology at William Rainey Harper College. Professor Hack has been using (APT) Automatically Programmed Tool Software since 1969 in his CAD/CAM Computer Aided Design and Manufacturing curriculum. Professor Hack teaches the use of APT programming languages for control of metal cutting machines. Machine tool instructions are geometry definitions written in APT Language to constitute a "part program." The part program is processed by the machine tool. CAD/CAM students go from writing a program to cutting steel in the course of a semester.

  7. NC Machine Tools Fault Diagnosis Based on Kernel PCA and k-Nearest Neighbor Using Vibration Signals

    Directory of Open Access Journals (Sweden)

    Zhou Yuqing

    2015-01-01

    Full Text Available This paper focuses on the fault diagnosis for NC machine tools and puts forward a fault diagnosis method based on kernel principal component analysis (KPCA and k-nearest neighbor (kNN. A data-dependent KPCA based on covariance matrix of sample data is designed to overcome the subjectivity in parameter selection of kernel function and is used to transform original high-dimensional data into low-dimensional manifold feature space with the intrinsic dimensionality. The kNN method is modified to adapt the fault diagnosis of tools that can determine thresholds of multifault classes and is applied to detect potential faults. An experimental analysis in NC milling machine tools is developed; the testing result shows that the proposed method is outperforming compared to the other two methods in tool fault diagnosis.

  8. EVALUATION OF MACHINE TOOL QUALITY

    Directory of Open Access Journals (Sweden)

    Ivan Kuric

    2011-12-01

    Full Text Available Paper deals with aspects of quality and accuracy of machine tools. As the accuracy of machine tools has key factor for product quality, it is important to know the methods for evaluation of quality and accuracy of machine tools. Several aspects of diagnostics of machine tools are described, such as aspects of reliability.

  9. Ultrasonic Vibration Electrical Discharge Machining in Gas

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A new method of ultrasonic vibration electrical discharge machining(UEDM) in gas is proposed in this paper. In UEDM in gas, the gap between tool electrode and workpiece is small(about 0.01mm), and the voltage between them is higher than EDM in liquid, so short circuit is easy to take place. It is very important for improving the MRR to avoid short circuit. Therefore, some measures have been taken, a rotation and a planetary motion are superimposed upon the tool electrode. During UEDM in gas, workpiece is vi...

  10. Automatically-Programed Machine Tools

    Science.gov (United States)

    Purves, L.; Clerman, N.

    1985-01-01

    Software produces cutter location files for numerically-controlled machine tools. APT, acronym for Automatically Programed Tools, is among most widely used software systems for computerized machine tools. APT developed for explicit purpose of providing effective software system for programing NC machine tools. APT system includes specification of APT programing language and language processor, which executes APT statements and generates NC machine-tool motions specified by APT statements.

  11. Automatically-Programed Machine Tools

    Science.gov (United States)

    Purves, L.; Clerman, N.

    1985-01-01

    Software produces cutter location files for numerically-controlled machine tools. APT, acronym for Automatically Programed Tools, is among most widely used software systems for computerized machine tools. APT developed for explicit purpose of providing effective software system for programing NC machine tools. APT system includes specification of APT programing language and language processor, which executes APT statements and generates NC machine-tool motions specified by APT statements.

  12. Analysis of machining and machine tools

    CERN Document Server

    Liang, Steven Y

    2016-01-01

    This book delivers the fundamental science and mechanics of machining and machine tools by presenting systematic and quantitative knowledge in the form of process mechanics and physics. It gives readers a solid command of machining science and engineering, and familiarizes them with the geometry and functionality requirements of creating parts and components in today’s markets. The authors address traditional machining topics, such as: single and multiple point cutting processes grinding components accuracy and metrology shear stress in cutting cutting temperature and analysis chatter They also address non-traditional machining, such as: electrical discharge machining electrochemical machining laser and electron beam machining A chapter on biomedical machining is also included. This book is appropriate for advanced undergraduate and graduate mechani cal engineering students, manufacturing engineers, and researchers. Each chapter contains examples, exercises and their solutions, and homework problems that re...

  13. Vibration characteristics of ultrasonic complex vibration for hole machining

    Science.gov (United States)

    Asami, Takuya; Miura, Hikaru

    2012-05-01

    Complex vibration sources that use diagonal slits as a longitudinal-torsional vibration converter have been applied to ultrasonic motors, ultrasonic rock drilling, and ultrasonic welding. However, there are few examples of the application of these sources to ultrasonic machining in combination with an abrasive. Accordingly, a new method has been developed for machining of holes in brittle materials by using the ultrasonic longitudinal and torsional vibration of a hollow-type stepped horn with a diagonal slit vibration converter. In this paper, we compared vibration of a uniform rod and a hollow-type stepped horn, both with diagonal slits, when the conditions of the diagonal slits are constant.

  14. Hinged Shields for Machine Tools

    Science.gov (United States)

    Lallande, J. B.; Poland, W. W.; Tull, S.

    1985-01-01

    Flaps guard against flying chips, but fold away for tool setup. Clear plastic shield in position to intercept flying chips from machine tool and retracted to give operator access to workpiece. Machine shops readily make such shields for own use.

  15. SIMULATION OF MULTI-SUPPORT MACHINE VIBRATIONS

    Directory of Open Access Journals (Sweden)

    N. N. Hurski

    2009-01-01

    Full Text Available The paper considers problems pertaining to simulation of multi-support machine vibrations by means of  ADMOS programming product. A mathematical model of the multi-support machine is presented and its main geometric and physical and mechanical parameters are given in the paper. The paper reveals analysis results of the vibration processes and observes variables in time and frequency areas. The investigations have made it possible to obtain amplitude and frequency and statistical characteristics  of  the machine mass centre acceleration during its motion along various types of roads

  16. Piezo Ceramic Actuators versus High Magnetostrictive Actuators in the Active control of Tool Vibration

    OpenAIRE

    Andrén, Linus; Håkansson, Lars; Claesson, Ingvar; Lagö, Thomas L.

    1999-01-01

    In the turning operation chatter or vibration is a frequent problem, which affects the result of the machining, and, in particular, the surface finish. Tool life is also influenced by vibration. Severe acoustic noise in the working environment frequently occurs as a result of dynamic motion between the cutting tool and the workpiece. These problems can be reduced by active control of machine-tool vibration. In the active control system for the control of tool vibration a tool holder construct...

  17. Mitigation of vibration in large electrical machines

    OpenAIRE

    Shahaj, Annabel

    2010-01-01

    In this study two new technologies are investigated with a view to improving the efficiency and reducing the vibrations of large electrical machines. These machines are used for high powered industrial applications. Individually controlled conductors are part of an active stator project that Converteam Ltd are developing. This involves individual conductors located in each stator slot that can be controlled separately. These replace traditional polyphase windings in order to provide a hi...

  18. Vibration-assisted machining of single crystal

    Science.gov (United States)

    Zahedi, S. A.; Roy, A.; Silberschmidt, V. V.

    2013-07-01

    Vibration-assisted machining offers a solution to expanding needs for improved machining, especially where accuracy and precision are of importance, such as in micromachining of single crystals of metals and alloys. Crystallographic anisotropy plays a crucial role in determining on overall response to machining. In this study, we intend to address the matter of ultra-precision machining of material at the micron scale using computational modelling. A hybrid modelling approach is implemented that combines two discrete schemes: smoothed particle hydrodynamics and continuum finite elements. The model is implemented in a commercial software ABAQUS/Explicit employing a user-defined subroutine (VUMAT) and used to elucidate the effect of crystallographic anisotropy on a response of face centred cubic (f.c.c.) metals to machining.

  19. Active Vibration Isolation System for Sub-microultra-precision Turning Machine

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    Now vibration isolation of ultra-precision machine tool is usually achieved through air-springs systems. As far as HCM-I sub-micro turning machine developed by HIT, an active vibration isolation system that consists of air-springs and electro-magnetic actuators was presented. The primary function of air-springs is to support the turning machine and to isolate the high-frequency vibration. The electro-magnetic actuators controlled by fuzzy-neural networks isolate the low-frequency vibration. The experiment indicates that active vibration isolation system isolates base-vibration effectively in all the frequency range. So the vibration of the machine bed is controlled under 10-6g and the surface roughness is improved.

  20. SDM applications to machine tools and engines

    Indian Academy of Sciences (India)

    A Sestieri

    2000-06-01

    The method of structural dynamic optimization is applied here to two real-life structures, a small two-cylinder, air-cooled gasoline engine and a high speed machine tool. The aim of the first application isthe reduction of the kinematic vibration transmission path composed of a piston-connecting rod, a crankshaft and an engine block, while the goal of the second application is the lowering of the peaks of the spindle-drive point FRFs measured along two orthogonal directions.It is shown how the addition of a small amount of mass at a few points on the engine block, and a small dynamic absorber with highly damped elastic connections provides the required improvements for the engine and the machine tool respectively.

  1. Monitoring Vibration of A Model of Rotating Machine

    Directory of Open Access Journals (Sweden)

    Arko Djajadi

    2012-03-01

    Full Text Available Mechanical movement or motion of a rotating machine normally causes additional vibration. A vibration sensing device must be added to constantly monitor vibration level of the system having a rotating machine, since the vibration frequency and amplitude cannot be measured quantitatively by only sight or touch. If the vibration signals from the machine have a lot of noise, there are possibilities that the rotating machine has defects that can lead to failure. In this experimental research project, a vibration structure is constructed in a scaled model to simulate vibration and to monitor system performance in term of vibration level in case of rotation with balanced and unbalanced condition. In this scaled model, the output signal of the vibration sensor is processed in a microcontroller and then transferred to a computer via a serial communication medium, and plotted on the screen with data plotter software developed using C language. The signal waveform of the vibration is displayed to allow further analysis of the vibration. Vibration level monitor can be set in the microcontroller to allow shutdown of the rotating machine in case of excessive vibration to protect the rotating machine from further damage. Experiment results show the agreement with theory that unbalance condition on a rotating machine can lead to larger vibration amplitude compared to balance condition. Adding and reducing the mass for balancing can be performed to obtain lower vibration level. 

  2. Machine Tool Operation, Course Description.

    Science.gov (United States)

    Denny, Walter E.; Anderson, Floyd L.

    Prepared by an instructor and curriculum specialists, this course of study was designed to meet the individual needs of the dropout and/or hard-core unemployed youth by providing them skill training, related information, and supportive services knowledge in machine tool operation. The achievement level of each student is determined at entry, and…

  3. [Research on infrared safety protection system for machine tool].

    Science.gov (United States)

    Zhang, Shuan-Ji; Zhang, Zhi-Ling; Yan, Hui-Ying; Wang, Song-De

    2008-04-01

    In order to ensure personal safety and prevent injury accident in machine tool operation, an infrared machine tool safety system was designed with infrared transmitting-receiving module, memory self-locked relay and voice recording-playing module. When the operator does not enter the danger area, the system has no response. Once the operator's whole or part of body enters the danger area and shades the infrared beam, the system will alarm and output an control signal to the machine tool executive element, and at the same time, the system makes the machine tool emergency stop to prevent equipment damaged and person injured. The system has a module framework, and has many advantages including safety, reliability, common use, circuit simplicity, maintenance convenience, low power consumption, low costs, working stability, easy debugging, vibration resistance and interference resistance. It is suitable for being installed and used in different machine tools such as punch machine, pour plastic machine, digital control machine, armor plate cutting machine, pipe bending machine, oil pressure machine etc.

  4. New active machine tool drive mounting on the frame

    Directory of Open Access Journals (Sweden)

    Švéda J.

    2007-10-01

    Full Text Available The paper deals with the new active mounting of the machine tool drives. The commonly used machine tools are at this time mainly equipped with fix-mounting of the feed drives. This structure causes full transmission of the force shocks to the machine bed and thereby restricts the dynamic properties of the motion axis and the whole machine. The spring-mounting of the feed drives is one of the possibilities how to partially suppress the vibrations. The force that reacts to the machine tool bed is transformed thereby the vibrations are lightly reduced. Unfortunately the transformation is not fully controlled. The new active mounting of the machine tool drives allows to fully control the force behaviour that react to the machine body. Thereby the number of excited frequencies on the machine tool bed is significantly reduced. The active variant of the feed drive mounting is characterized by the synergistic cooperation between two series-connected actuators (“motor on motor”. The paper briefly describes design, control techniques and optimization of the feed drives with the new active mounting conception.

  5. Design of equipment for training machine tools

    Directory of Open Access Journals (Sweden)

    Císar Miroslav

    2017-01-01

    Full Text Available The article proposes multiple devices designed to be used with training machine tools EMCO Concept series. Design was focused to enchant educational potential of training machine tools located in the laboratory of CNC programing, department of automation and production systems, Faculty of mechanical engineering, University of Zilina. The described device allows monitoring of machine tool, to measure tool offset and dimension, to use alternative ways of clamping, and to create video of machining.

  6. Standardized Curriculum for Machine Tool Operation/Machine Shop.

    Science.gov (United States)

    Mississippi State Dept. of Education, Jackson. Office of Vocational, Technical and Adult Education.

    Standardized vocational education course titles and core contents for two courses in Mississippi are provided: machine tool operation/machine shop I and II. The first course contains the following units: (1) orientation; (2) shop safety; (3) shop math; (4) measuring tools and instruments; (5) hand and bench tools; (6) blueprint reading; (7)…

  7. Cast Iron And Mineral Cast Applied For Machine Tool Bed - Dynamic Behavior Analysis

    OpenAIRE

    2015-01-01

    Cast iron and mineral cast are the materials most often used in the machine structural elements design (bodies, housings, machine tools beds etc.). The materials significantly differ in physical and mechanical properties. The ability to suppress vibration is one of the most important factors determining the dynamic properties of the machine and has a significant impact on the machining capabilities of a machine tool. Recent research and development trends show that there is a clear tendency t...

  8. Calibration of a Parallel Kinematic Machine Tool

    Institute of Scientific and Technical Information of China (English)

    HE Xiao-mei; DING Hong-sheng; FU Tie; XIE Dian-huang; XU Jin-zhong; LI Hua-feng; LIU Hui-lin

    2006-01-01

    A calibration method is presented to enhance the static accuracy of a parallel kinematic machine tool by using a coordinate measuring machine and a laser tracker. According to the established calibration model and the calibration experiment, the factual 42 kinematic parameters of BKX-I parallel kinematic machine tool are obtained. By circular tests the comparison is made between the calibrated and the uncalibrated parameters and shows that there is 80% improvement in accuracy of this machine tool.

  9. Active vibration isolation of high precision machines

    CERN Document Server

    Collette, C; Artoos, K; Hauviller, C

    2010-01-01

    This paper provides a review of active control strategies used to isolate high precisionmachines (e.g. telescopes, particle colliders, interferometers, lithography machines or atomic force microscopes) from external disturbances. The objective of this review is to provide tools to develop the best strategy for a given application. Firstly, the main strategies are presented and compared, using single degree of freedom models. Secondly, the case of huge structures constituted of a large number of elements, like particle colliders or segmented telescopes, is considered.

  10. Attaching Chuck Keys to Machine Tools

    Science.gov (United States)

    Richardson, V.

    1984-01-01

    Chuck keys attached to portable machine tools by retracting lanyards. Lanyard held taut by recoil caddy attached to tool base. Chuck key available for use when needed and safely secured during operation of tool.

  11. Cutting tool materials for high speed machining

    Institute of Scientific and Technical Information of China (English)

    LIU Zhanqiang; AI Xing

    2005-01-01

    High speed machining (HSM) is one of the emerging cutting processes, which is machining at a speed significantlyhigher than the speed commonly in use on the shop floor. In the last twenty years, high speed machining has received great attentions as a technological solution for high productivity in manufacturing. This article reviews the developments of tool materials in high speed machining operations, and the properties, applications and prospective developments of tool materials in HSM are also presented.

  12. How To Teach Common Characteristics of Machine Tools

    Science.gov (United States)

    Kazanas, H. C.

    1970-01-01

    Organizes machine tools and machine operations into commonalities in order to help the student visualize and distinguish the common characteristics which exist between machine tools and operations. (GR)

  13. Chip breaking system for automated machine tool

    Science.gov (United States)

    Arehart, Theodore A.; Carey, Donald O.

    1987-01-01

    The invention is a rotary selectively directional valve assembly for use in an automated turret lathe for directing a stream of high pressure liquid machining coolant to the interface of a machine tool and workpiece for breaking up ribbon-shaped chips during the formation thereof so as to inhibit scratching or other marring of the machined surfaces by these ribbon-shaped chips. The valve assembly is provided by a manifold arrangement having a plurality of circumferentially spaced apart ports each coupled to a machine tool. The manifold is rotatable with the turret when the turret is positioned for alignment of a machine tool in a machining relationship with the workpiece. The manifold is connected to a non-rotational header having a single passageway therethrough which conveys the high pressure coolant to only the port in the manifold which is in registry with the tool disposed in a working relationship with the workpiece. To position the machine tools the turret is rotated and one of the tools is placed in a material-removing relationship of the workpiece. The passageway in the header and one of the ports in the manifold arrangement are then automatically aligned to supply the machining coolant to the machine tool workpiece interface for breaking up of the chips as well as cooling the tool and workpiece during the machining operation.

  14. A defect-driven diagnostic method for machine tool spindles.

    Science.gov (United States)

    Vogl, Gregory W; Donmez, M Alkan

    2015-01-01

    Simple vibration-based metrics are, in many cases, insufficient to diagnose machine tool spindle condition. These metrics couple defect-based motion with spindle dynamics; diagnostics should be defect-driven. A new method and spindle condition estimation device (SCED) were developed to acquire data and to separate system dynamics from defect geometry. Based on this method, a spindle condition metric relying only on defect geometry is proposed. Application of the SCED on various milling and turning spindles shows that the new approach is robust for diagnosing the machine tool spindle condition.

  15. Cases of coupled vibrations and prametric instability in rotating machines

    OpenAIRE

    Luneno, Jean-Claude

    2012-01-01

    The principal task in this research project was to analyse the causes and consequences of coupled vibrations and parametric instability in hydropower rotors; where both horizontal and vertical machines are involved. Vibration is a well-known undesirable behavior of dynamical systems characterised by persistent periodic, quasi-periodic or chaotic motions. Vibrations generate noise and cause fatigue, which initiates cracks in mechanical structures. Motions coupling can in some cases augment the...

  16. Caracterización Dinámica de Máquinas Herramienta y Diseño de un Sistema Activo de Reducción de Vibraciones durante el Mecanizado Dynamic Characterization of Machine Tool and Design of an Active System for the Reduction of Vibration during Machining

    Directory of Open Access Journals (Sweden)

    E Zamora

    2004-01-01

    Full Text Available En este trabajo se presenta una metodología para la caracterización dinámica de máquinas herramienta, así como una propuesta de sistema de control que permite la reducción de vibraciones durante el proceso de mecanizado utilizando un actuador piezoeléctrico. Esta metodología consta de las siguientes cuatro etapas: identificación de las características dinámicas del sistema, elaboración de un modelo matemático, definición de las características dinámicas del actuador y desarrollo e implantación de la rutina de control. La metodología propuesta fue aplicada en un centro de mecanizado vertical y se midieron los niveles de vibración durante el mecanizado de paredes delgadas en una pieza de aluminio. Se concluye que la metodología propuesta disminuye considerablemente el nivel de vibración presente durante la operación de mecanizado.This work presents a methodology for the dynamic characterization of machine tools, as well as a control system that makes use of a piezoelectric actuator for vibration reduction during the process of machining. The methodology consists of the following four steps: identification of the dynamic characteristic of the system, implementation of a mathematical model, definition of the dynamic characteristics of the actuator and development and installation of the control algorithm. The proposed methodology has been applied in a vertical machining center and the vibration level during the machining of thin walls in an aluminum piece have been measured. It is concluded that the proposed methodology reduces considerably the vibration level present during the milling operation.

  17. Confirmation of Thermal Images and Vibration Signals for Intelligent Machine Fault Diagnostics

    Directory of Open Access Journals (Sweden)

    Achmad Widodo

    2012-01-01

    Full Text Available This paper deals with the maintenance technique for industrial machinery using the artificial neural network so-called self-organizing map (SOM. The aim of this work is to develop intelligent maintenance system for machinery based on an alternative way, namely, thermal images instead of vibration signals. SOM is selected due to its simplicity and is categorized as an unsupervised algorithm. Following the SOM training, machine fault diagnostics is performed by using the pattern recognition technique of machine conditions. The data used in this work are thermal images and vibration signals, which were acquired from machine fault simulator (MFS. It is a reliable tool and is able to simulate several conditions of faulty machine such as unbalance, misalignment, looseness, and rolling element bearing faults (outer race, inner race, ball, and cage defects. Data acquisition were conducted simultaneously by infrared thermography camera and vibration sensors installed in the MFS. The experimental data are presented as thermal image and vibration signal in the time domain. Feature extraction was carried out to obtain salient features sensitive to machine conditions from thermal images and vibration signals. These features are then used to train the SOM for intelligent machine diagnostics process. The results show that SOM can perform intelligent fault diagnostics with plausible accuracies.

  18. Design of Five-Axis Ultrasonic Assistant Compound Machine Tool

    Institute of Scientific and Technical Information of China (English)

    Liu Bing刘冰; Fang Fengzhou房丰洲; Xu Zongwei徐宗伟; Zhang Xiaofeng张晓峰

    2015-01-01

    A compound machine tool was designed, which combined rotary ultrasonic assisted grinding, electrical discharge machining (EDM) and multi-axis milling. Experimental results indicated that its positioning accuracy was less than 5.6μm and its repetitive positioning accuracy was less than 1.8μm;the vibration amplitude of ultrasonic grinding system was uniform and stable, and the EDM system worked well and stably.A smooth surface of K9 optical glass component was achieved by the grinding method.

  19. Static and Dynamic Performance Improvement of Conventional Computer Numerical Control Machine Tool Bed with Hybrid Welded Steel

    OpenAIRE

    S. S. Abuthakeer; P. V. Mohanram; G. Mohankumar

    2011-01-01

    Problem statement: The advancements in machine tools to maximize the production by increasing spindle speeds have caused vibration in machine tools. The two functional requirements of machine tool bed for machine tools are high structural stiffness and high damping, which cannot be satisfied simultaneously if conventional metallic materials such as cast iron are employed. Hence there is a need to replace cast iron with alternate materials. Approach: The objective of this study is to improve t...

  20. Semiactive Vibration Control for Horizontal Axis Washing Machine

    Directory of Open Access Journals (Sweden)

    Barış Can Yalçın

    2015-01-01

    Full Text Available A semiactive vibration control method is developed to cope with the dynamic stability problem of a horizontal axis washing machine. This method is based on adjusting the maximum force values produced by the semiactive suspension elements considering a washing machine’s vibration data (three axis angular position and three axis angular acceleration values in time. Before actuation signals are received by the step motors of the friction dampers, vibration data are evaluated, and then, the step motors start to narrow or expand the radius of bracelets located on the dampers. This changes the damping properties of the damper in the suspension system, and thus, the semiactive suspension system absorbs unwanted vibrations and contributes to the dynamic stability of the washing machine. To evaluate the vibration data, the angular position and angular acceleration values in three axes are defined in a function, and the maximum forces produced by semiactive suspension elements are calculated according to the gradient of this function. The relation between the dynamic stability and the walking stability is also investigated. A motion (gyroscope and accelerometer sensor is installed on the top-front panel of the washing machine because a mathematical model of a horizontal axis washing machine suggests that the walking behavior starts around this location under some assumptions, and therefore, calculating the vibrations occurring there is crucial. Semiactive damping elements are located under the left and right sides of the tub. The proposed method is tested during the spinning cycle of washing machine operation, increasing gradually from 200 rpm to 900 rpm, which produces the most challenging vibration patterns for dynamic stability. Moreover, the sound power levels produced by the washing machine are measured to evaluate the noise performance of the washing machine while the semiactive suspension system is controlled. The effectiveness of the

  1. Development of active vibration isolation system for precision machines

    Science.gov (United States)

    Li, H. Z.; Lin, W. J.; Yang, G. L.

    2010-03-01

    It is a common understanding by manufacturers of precision machines that vibrations are a potentially disastrous threat to precision and throughput. To satisfy the quest for more stable processes and tighter critical dimension control in the microelectronics manufacturing industry, active vibration control becomes increasingly important for high-precision equipment developers. This paper introduced the development of an active vibration isolation system for precision machines. Innovative mechatronic approaches are investigated that can effectively suppress both environmental and payload-generated vibration. In this system, accelerometers are used as the feedback sensor, voice coil motors are used to generate the counter force, and a TI DSP controller is used to couple sensor measurements to actuator forces via specially designed control algorithms in real-time to counteract the vibration disturbances. Experimental results by using the developed AVI prototype showed promising performance on vibration attenuation. It demonstrated a reduction of the settling time from 2s to 0.1s under impulsive disturbances; and a vibration attenuation level of more than 20dB for harmonic disturbances. The technology can be used to suppress vibration for a wide range of precision machines to achieve fast settling time and higher accuracy.

  2. Speed-Selector Guard For Machine Tool

    Science.gov (United States)

    Shakhshir, Roda J.; Valentine, Richard L.

    1992-01-01

    Simple guardplate prevents accidental reversal of direction of rotation or sudden change of speed of lathe, milling machine, or other machine tool. Custom-made for specific machine and control settings. Allows control lever to be placed at only one setting. Operator uses handle to slide guard to engage or disengage control lever. Protects personnel from injury and equipment from damage occurring if speed- or direction-control lever inadvertently placed in wrong position.

  3. USSR Report Machine Tools and Metalworking Equipment

    Science.gov (United States)

    2007-11-02

    determined, therefore, by the shape of the machined surface and is spatial , i.e., kinematically the most complicated one, different for each machined...place in a single hour. But in actuality? Perhaps it began when they began to study the loading of the production capacities of the sections... kindergartens , the machine tools are outdated and there is nowhere to rest." "At that time I said to myself: ’First achieve their confidence; this

  4. Method for machining steel with diamond tools

    Science.gov (United States)

    Casstevens, John M.

    1986-01-01

    The present invention is directed to a method for machining optical quality inishes and contour accuracies of workpieces of carbon-containing metals such as steel with diamond tooling. The wear rate of the diamond tooling is significantly reduced by saturating the atmosphere at the interface of the workpiece and the diamond tool with a gaseous hydrocarbon during the machining operation. The presence of the gaseous hydrocarbon effectively eliminates the deterioration of the diamond tool by inhibiting or preventing the conversion of the diamond carbon to graphite carbon at the point of contact between the cutting tool and the workpiece.

  5. Numerically Controlled Machine Tools and Worker Skills.

    Science.gov (United States)

    Keefe, Jeffrey H.

    1991-01-01

    Analysis of data from "Industry Wage Surveys of Machinery Manufacturers" on the skill levels of 57 machining jobs found that introduction of numerically controlled machine tools has resulted in a very small reduction in skill levels or no significant change, supporting neither the deskilling argument nor argument that skill levels…

  6. Machine Tool Series. Duty Task List.

    Science.gov (United States)

    Oklahoma State Dept. of Vocational and Technical Education, Stillwater. Curriculum and Instructional Materials Center.

    This task list is intended for use in planning and/or evaluating a competency-based course to prepare machine tool, drill press, grinding machine, lathe, mill, and/or power saw operators. The listing is divided into six sections, with each one outlining the tasks required to perform the duties that have been identified for the given occupation.…

  7. Numerically Controlled Machine Tools and Worker Skills.

    Science.gov (United States)

    Keefe, Jeffrey H.

    1991-01-01

    Analysis of data from "Industry Wage Surveys of Machinery Manufacturers" on the skill levels of 57 machining jobs found that introduction of numerically controlled machine tools has resulted in a very small reduction in skill levels or no significant change, supporting neither the deskilling argument nor argument that skill levels…

  8. Ultrasonic vibrating system design and tool analysis

    Institute of Scientific and Technical Information of China (English)

    Kei-Lin KUO

    2009-01-01

    The applications of ultrasonic vibrations for material removal processes exist predominantly in the area of vertical processing of hard and brittle materials. This is because the power generated by vertical vibrating oscillators generates the greatest direct penetration, in order to conduct material removal on workpieces by grains. However, for milling processes, vertical vibrating power has to be transformed into lateral (horizontal) vibration to produce the required horizontal cutting force. The objective of this study is to make use of ultrasonic lateral transformation theory to optimize processing efficiency, through the use of the finite element method for design and analysis of the milling tool. In addition, changes can be made to the existing vibrating system to generate best performance under consistent conditions, namely, using the same piezoelectric ceramics.

  9. Transition Towards Energy Efficient Machine Tools

    CERN Document Server

    Zein, André

    2012-01-01

    Energy efficiency represents a cost-effective and immediate strategy of a sustainable development. Due to substantial environmental and economic implications, a strong emphasis is put on the electrical energy requirements of machine tools for metalworking processes. The improvement of energy efficiency is however confronted with diverse barriers, which sustain an energy efficiency gap of unexploited potential. The deficiencies lie in the lack of information about the actual energy requirements of machine tools, a minimum energy reference to quantify improvement potential and the possible actions to improve the energy demand. Therefore, a comprehensive concept for energy performance management of machine tools is developed which guides the transition towards energy efficient machine tools. It is structured in four innovative concept modules, which are embedded into step-by-step workflow models. The capability of the performance management concept is demonstrated in an automotive manufacturing environment. The ...

  10. Refrigerated cutting tools improve machining of superalloys

    Science.gov (United States)

    Dudley, G. M.

    1971-01-01

    Freon-12 applied to tool cutting edge evaporates quickly, leaves no residue, and permits higher cutting rate than with conventional coolants. This technique increases cutting rate on Rene-41 threefold and improves finish of machined surface.

  11. NEW TYPE OF VIBRATION STRUCTURE OF VERTICAL DYNAMIC BALANCING MACHINE

    Institute of Scientific and Technical Information of China (English)

    Li Dinggen; Cao Jiguang; Chen Chuanyao; Wang Junwen

    2004-01-01

    A new type of vibration structure of vertical dynamic balancing machine is designed, which is based on the analysis for swing frame of a traditional vertical dynamic balancing machine. The static unbalance and couple unbalance can be separated effectively by using the new machine with the new swing frame. By building the dynamics model, the advantages of the new structure are discussed in detail. The modal and harmonic response are analyzed by using the ANSYS7.0. By comparing the finite element modal analysis with the experimental modal analysis, the natural frequencies and vibration modes are found out. There are many spring boards in the new swing frame. Their stiffness is different and assort with each other. Furthermore, there are three sensors on the measurement points. Therefore, the new dynamic balancing machine can measure the static unbalance and couple unbalance directly, and the influence between them is faint. The new structure has the function of belt-strain compensation to improve the measurement precision. The practical result indicates that the new vertical dynamic balancing machine is suitable for inertial measurement of flying objects, and can overcome the shortcomings of traditional double-plane vertical dynamic balancing machines. The vertical dynamic balancing machine with the new vibration structure can be widely used in the future applications. The modeling and analysis of the new vibration structure provide theoretic instruction and practical experience for designing new type of vertical dynamic balancing machines. Based on the design principles such as stiffness-matching, frequency-adjacence and strain-compensation and so on, various new type of vibration structures can be designed.

  12. Actuator design for vibration assisted machining of high performance materials with ultrasonically modulated cutting speed

    Science.gov (United States)

    Rinck, Philipp M.; Sitzberger, Sebastian; Zaeh, Michael F.

    2017-06-01

    In vibration assisted machining, an additional high-frequency oscillation is superimposed on the kinematics of the conventional machining process. This generates oscillations on the cutting edge in the range of a few micrometers, thereby causing a high-frequency change in the cutting speed or the feed. Consequently, a reduction of cutting forces, an increase of the tool life as well as an improvement of the workpiece quality can be achieved. In milling and grinding it has been shown that these effects are already partially present in the case of a vibration excitation in axial direction relative to the workpiece, which is perpendicular to the cutting direction. Further improvements of the process results can be achieved by superimposing a vibration in cutting direction and thus modifying the cutting speed at high frequency. The presented work shows the design of an ultrasonic actuator that enables vibration-assisted milling and grinding with ultrasonically modulated cutting speed. The actuator system superimposes a longitudinal torsional ultrasonic oscillation to the milling or grinding tool. It uses a bolt clamped Langevin transducer and a helically slotted horn, which degenerates the longitudinal vibration into a combined longitudinal torsional (L-T) vibration at the output surface. A finite element analysis is used to determine the vibration resonance frequency and mode shapes to maximize the torsional output. Afterwards, the simulation has been experimentally validated.

  13. Prediction and Control of Cutting Tool Vibration in Cnc Lathe with Anova and Ann

    Directory of Open Access Journals (Sweden)

    S. S. Abuthakeer

    2011-06-01

    Full Text Available Machining is a complex process in which many variables can deleterious the desired results. Among them, cutting tool vibration is the most critical phenomenon which influences dimensional precision of the components machined, functional behavior of the machine tools and life of the cutting tool. In a machining operation, the cutting tool vibrations are mainly influenced by cutting parameters like cutting speed, depth of cut and tool feed rate. In this work, the cutting tool vibrations are controlled using a damping pad made of Neoprene. Experiments were conducted in a CNC lathe where the tool holder is supported with and without damping pad. The cutting tool vibration signals were collected through a data acquisition system supported by LabVIEW software. To increase the buoyancy and reliability of the experiments, a full factorial experimental design was used. Experimental data collected were tested with analysis of variance (ANOVA to understand the influences of the cutting parameters. Empirical models have been developed using analysis of variance (ANOVA. Experimental studies and data analysis have been performed to validate the proposed damping system. Multilayer perceptron neural network model has been constructed with feed forward back-propagation algorithm using the acquired data. On the completion of the experimental test ANN is used to validate the results obtained and also to predict the behavior of the system under any cutting condition within the operating range. The onsite tests show that the proposed system reduces the vibration of cutting tool to a greater extend.

  14. Tool-specific performance of vibration-reducing gloves for attenuating palm-transmitted vibrations in three orthogonal directions.

    Science.gov (United States)

    Dong, Ren G; Welcome, Daniel E; Peterson, Donald R; Xu, Xueyan S; McDowell, Thomas W; Warren, Christopher; Asaki, Takafumi; Kudernatsch, Simon; Brammer, Antony

    2014-11-01

    Vibration-reducing (VR) gloves have been increasingly used to help reduce vibration exposure, but it remains unclear how effective these gloves are. The purpose of this study was to estimate tool-specific performances of VR gloves for reducing the vibrations transmitted to the palm of the hand in three orthogonal directions (3-D) in an attempt to assess glove effectiveness and aid in the appropriate selection of these gloves. Four typical VR gloves were considered in this study, two of which can be classified as anti-vibration (AV) gloves according to the current AV glove test standard. The average transmissibility spectrum of each glove in each direction was synthesized based on spectra measured in this study and other spectra collected from reported studies. More than seventy vibration spectra of various tools or machines were considered in the estimations, which were also measured in this study or collected from reported studies. The glove performance assessments were based on the percent reduction of frequency-weighted acceleration as is required in the current standard for assessing the risk of vibration exposures. The estimated tool-specific vibration reductions of the gloves indicate that the VR gloves could slightly reduce (<5%) or marginally amplify (<10%) the vibrations generated from low-frequency (<25 Hz) tools or those vibrating primarily along the axis of the tool handle. With other tools, the VR gloves could reduce palm-transmitted vibrations in the range of 5%-58%, primarily depending on the specific tool and its vibration spectra in the three directions. The two AV gloves were not more effective than the other gloves with some of the tools considered in this study. The implications of the results are discussed.

  15. A Study on the Reliability of a Large Vibration Machine

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    This study aims at the reliability of a large vibration machine ZM2800, including the measurement and analysis of its dynamic load, the stress and reliability analysis of key fragile components as well as the system reliability analysis and calculation of the ma chine. The result of the study provides valuable reference for the evaluation and improve-ment of the structure and performance of the machine.

  16. Machine Translation Tools - Tools of The Translator's Trade

    DEFF Research Database (Denmark)

    Kastberg, Peter

    2012-01-01

    In this article three of the more common types of translation tools are presented, discussed and critically evaluated. The types of translation tools dealt with in this article are: Fully Automated Machine Translation (or FAMT), Human Aided Machine Translation (or HAMT) and Machine Aided Human...... Translation (or MAHT). The strengths and weaknesses of the different types of tools are discussed and evaluated by means of a number of examples. The article aims at two things: at presenting a sort of state of the art of what is commonly referred to as “machine translation” as well as at providing the reader...... with a sound basis for considering what translation tool (if any) is the most appropriate in order to meet his or her specific translation needs....

  17. Automatic Calibration Of Manual Machine Tools

    Science.gov (United States)

    Gurney, Rex D.

    1990-01-01

    Modified scheme uses data from multiple positions and eliminates tedious positioning. Modification of computer program adapts calibration system for convenient use with manually-controlled machine tools. Developed for use on computer-controlled tools. Option added to calibration program allows data on random tool-axis positions to be entered manually into computer for reduction. Instead of setting axis to predetermined positions, operator merely sets it at variety of arbitrary positions.

  18. ADAPTABLE DESIGN OF MACHINE TOOLS STRUCTURES

    Institute of Scientific and Technical Information of China (English)

    XU Yanshen; CHEN Yongliang; ZHANG Guojun; GU Peihua

    2008-01-01

    Adaptable design aims to extend the utilities of design and product. The specific methods are developed for practical applications of adaptable design in the design of mechanical structures, including adaptable platform, interface and module designs. Adaptable redesign problems are formulated as adaptable platform design under adaptability bound constraints. Analysis tools are then suggested for the implementation of the redesign of machine tool structures, including variation techniques based sensitivity analysis, similarity-based commonality analysis, performance improvement, and adaptability measures. The specific measure of adaptability for machine tool structures is measured through the quantification of the structural similarity and performance improvement gained from adaptable design. The method provides designers with an approach that brings adaptability into the design process, with considering the cost and benefits of such adaptability. The redesign of CNC spiral bevel gear cutting machine structures has been included to illustrate these concepts and methods.

  19. Vibration Attenuation in Rotating Machines Using Smart Spring Mechanism

    Directory of Open Access Journals (Sweden)

    Aldemir Ap. Cavalini

    2011-01-01

    Full Text Available This paper proposes a semiactive vibration control technique dedicated to a rotating machine passing by its critical speed during the transient rotation, by using a Smart Spring Mechanism (SSM. SSM is a patented concept that, using an indirect piezoelectric (PZT stack actuation, changes the stiffness characteristics of one or more rotating machine bearings to suppress high vibration amplitudes. A Genetic Algorithm (GA optimization technique is used to determine the best design of the SSM parameters with respect to performance indexes associated with the control efficiency. Additionally, the concept of ecologically correct systems is incorporated to this work including the PZT stack energy consumption in the indexes considered for the optimization process. Simulation carried out on Finite Element Method (FEM model suggested the feasibility of the SSM for vibration attenuation of rotors for different operating conditions and demonstrated the possibility of incorporating SSM devices to develop high-performance ecologic control systems.

  20. Program Design Report of the CNC Machine Tool(II)

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jong Kiun; Youm, K. U.; Kim, K. S.; Lee, I. B.; Yoon, K. B.; Lee, C. K.; Youm, J. H

    2007-06-15

    The application of CNC machine tool being widely expanded according to variety of machine work method and rapid promotion of machine tool, cutting tool, for high speed efficient machine work. In order to conduct of the project of manufacture and maintenance of laboratory equipment, production design and machine work technology are continually developed, especially the application of CNC machine tool is very important for the improvement of productivity, quality and clearing up a manpower shortage. We publish technical report which it includes CNC machine tool program and drawing, it contributes to the systematic development of CNC program design and machine work technology.

  1. Sine-Bar Attachment For Machine Tools

    Science.gov (United States)

    Mann, Franklin D.

    1988-01-01

    Sine-bar attachment for collets, spindles, and chucks helps machinists set up quickly for precise angular cuts that require greater precision than provided by graduations of machine tools. Machinist uses attachment to index head, carriage of milling machine or lathe relative to table or turning axis of tool. Attachment accurate to 1 minute or arc depending on length of sine bar and precision of gauge blocks in setup. Attachment installs quickly and easily on almost any type of lathe or mill. Requires no special clamps or fixtures, and eliminates many trial-and-error measurements. More stable than improvised setups and not jarred out of position readily.

  2. Sine-Bar Attachment For Machine Tools

    Science.gov (United States)

    Mann, Franklin D.

    1988-01-01

    Sine-bar attachment for collets, spindles, and chucks helps machinists set up quickly for precise angular cuts that require greater precision than provided by graduations of machine tools. Machinist uses attachment to index head, carriage of milling machine or lathe relative to table or turning axis of tool. Attachment accurate to 1 minute or arc depending on length of sine bar and precision of gauge blocks in setup. Attachment installs quickly and easily on almost any type of lathe or mill. Requires no special clamps or fixtures, and eliminates many trial-and-error measurements. More stable than improvised setups and not jarred out of position readily.

  3. Development of non-contact structural health monitoring system for machine tools

    Directory of Open Access Journals (Sweden)

    Deepam Goyal

    2016-08-01

    Full Text Available In this era of flexible manufacturing systems, a real-time structural health monitoring (SHM is paramount for machining processes which are of great relevance today, when there is a constant call for better productivity with high quality at low price. During machining, vibrations are always brought forth because of mechanical disturbances from various sources such as an engine, a sound, and noise, among others. A SHM system provides significant economic benefits when applied to machine tools and machining processes. This study demonstrates a non contact SHM system for machine tools based on the vibration signal collected through a low-cost, microcontroller based data acquisition system. The examination tests of this developed system have been carried out on a vibration rig. The readings have also been calibrated with the accelerometer to validate the proposed system. The developed system results in quick measurement, enables reliable monitoring, and is cost effective with no need to alter the structure of the machine tool. It is expected that the system can forewarn the operator for timely based maintenance actions in addition to reducing the costs of machine downtime and acquiring equipments with reduction in complexity of machine tools.

  4. Machine-Tool Technology Instructor's Sourcebook.

    Science.gov (United States)

    Tammer, Anthony M.

    This document lists and annotates commercial and noncommercial resources pertaining to machine-tool technology. Following an introduction that explains how the document came to be written, the subjects of succeeding chapters are (1) periodicals; (2) associations; (3) audiovisual resources, including a subject index; (4) publishers, including a…

  5. Technology network for machine tools in Vietnam

    OpenAIRE

    Mizuno, Junko

    2012-01-01

    When Vietnam joined the WTO, it accepted foreign direct investment and started to grow. Technically, it was then greatly influenced by the enterprises that entered the country through direct investment. This report shows that the technology network for machine tools is formed via direct investment and subcontracting.

  6. Vibration suppression in cutting tools using collocated piezoelectric sensors/actuators with an adaptive control algorithm

    Energy Technology Data Exchange (ETDEWEB)

    Radecki, Peter P [Los Alamos National Laboratory; Farinholt, Kevin M [Los Alamos National Laboratory; Park, Gyuhae [Los Alamos National Laboratory; Bement, Matthew T [Los Alamos National Laboratory

    2008-01-01

    The machining process is very important in many engineering applications. In high precision machining, surface finish is strongly correlated with vibrations and the dynamic interactions between the part and the cutting tool. Parameters affecting these vibrations and dynamic interactions, such as spindle speed, cut depth, feed rate, and the part's material properties can vary in real-time, resulting in unexpected or undesirable effects on the surface finish of the machining product. The focus of this research is the development of an improved machining process through the use of active vibration damping. The tool holder employs a high bandwidth piezoelectric actuator with an adaptive positive position feedback control algorithm for vibration and chatter suppression. In addition, instead of using external sensors, the proposed approach investigates the use of a collocated piezoelectric sensor for measuring the dynamic responses from machining processes. The performance of this method is evaluated by comparing the surface finishes obtained with active vibration control versus baseline uncontrolled cuts. Considerable improvement in surface finish (up to 50%) was observed for applications in modern day machining.

  7. Performance of a table vibration type coffee grading machine

    Directory of Open Access Journals (Sweden)

    Sukrisno Widyotomo

    2005-05-01

    Full Text Available One of important coffee beans quality is the size uniformity. To confirm with the standart requirement, coffee beans have to be graded before being traded. Until now, grading process is still carried out fully manual, so that the grading cost is very expensive about 40% of total processing cost. Meanwhile, shortage of skill workers is as a limiting factor of the process. Therefore, machine for grading coffee beans is good alternative for grading cost. Indonesian Coffee and Cocoa Research Institute has designed a table vibration type coffee grading machine for grouping of coffee beans in order to consistent quality and reduce grading cost. The machine has dimension of 272 cm length, 126 cm height, and 144 cm width. The machine has three primary components, i.e. grader table, combustion engine, and beam. The machine has three kinds of grader table that each grader table has different holes size, i.e. 7 mm x 7 mm for top grader table, 5 mm x 5 mm for axle grader table, and 4 mm x 4 mm for bottom grader table. Each grader table has dimension of 206 cm length, 105.5 cm height, and 14 cm width. The grading mechanism is by vibration grader table with the power source 5.5 HP combustion engine. The results shown that the outlet are in farms of three grades of coffee beans with connected to each compartement. Assessment of the grading machine reveals that the optimum capacity of 1,406 kg/hour reached when the speed 2,600 rpm and the angle 10O. Economic analysis showed that operational cost for grading one kilogram Robusta coffee beans with moisture content 13—14% wet basis is Rp 7.17.Key words : grading, coffee, quality, vibration table.

  8. ATST telescope mount: telescope of machine tool

    Science.gov (United States)

    Jeffers, Paul; Stolz, Günter; Bonomi, Giovanni; Dreyer, Oliver; Kärcher, Hans

    2012-09-01

    The Advanced Technology Solar Telescope (ATST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope mount has proportions similar to an 8 meter class telescope. The technology normally used in this class of telescope is well understood in the telescope community and has been successfully implemented in numerous projects. The world of large machine tools has developed in a separate realm with similar levels of performance requirement but different boundary conditions. In addition the competitive nature of private industry has encouraged development and usage of more cost effective solutions both in initial capital cost and thru-life operating cost. Telescope mounts move relatively slowly with requirements for high stability under external environmental influences such as wind buffeting. Large machine tools operate under high speed requirements coupled with high application of force through the machine but with little or no external environmental influences. The benefits of these parallel development paths and the ATST system requirements are being combined in the ATST Telescope Mount Assembly (TMA). The process of balancing the system requirements with new technologies is based on the experience of the ATST project team, Ingersoll Machine Tools who are the main contractor for the TMA and MT Mechatronics who are their design subcontractors. This paper highlights a number of these proven technologies from the commercially driven machine tool world that are being introduced to the TMA design. Also the challenges of integrating and ensuring that the differences in application requirements are accounted for in the design are discussed.

  9. PREDICTION OF TOOL CONDITION DURING TURNING OF ALUMINIUM/ALUMINA/GRAPHITE HYBRID METAL MATRIX COMPOSITES USING MACHINE LEARNING APPROACH

    Directory of Open Access Journals (Sweden)

    N. RADHIKA

    2015-10-01

    Full Text Available Aluminium/alumina/graphite hybrid metal matrix composites manufactured using stir casting technique was subjected to machining studies to predict tool condition during machining. Fresh tool as well as tools with specific amount of wear deliberately created prior to machining experiments was used. Vibration signals were acquired using an accelerometer for each tool condition. These signals were then processed to extract statistical and histogram features to predict the tool condition during machining. Two classifiers namely, Random Forest and Classification and Regression Tree (CART were used to classify the tool condition. Results showed that histogram features with Random Forest classifier yielded maximum efficiency in predicting the tool condition. This machine learning approach enables the prediction of tool failure in advance, thereby minimizing the unexpected breakdown of tool and machine.

  10. Machine tool metrology an industrial handbook

    CERN Document Server

    Smith, Graham T

    2016-01-01

    Maximizing reader insights into the key scientific disciplines of Machine Tool Metrology, this text will prove useful for the industrial-practitioner and those interested in the operation of machine tools. Within this current level of industrial-content, this book incorporates significant usage of the existing published literature and valid information obtained from a wide-spectrum of manufacturers of plant, equipment and instrumentation before putting forward novel ideas and methodologies. Providing easy to understand bullet points and lucid descriptions of metrological and calibration subjects, this book aids reader understanding of the topics discussed whilst adding a voluminous-amount of footnotes utilised throughout all of the chapters, which adds some additional detail to the subject. Featuring an extensive amount of photographic-support, this book will serve as a key reference text for all those involved in the field. .

  11. Parametric programming of CNC machine tools

    Directory of Open Access Journals (Sweden)

    Gołębski Rafał

    2017-01-01

    Full Text Available The article presents the possibilities of parametric programming of CNC machine tools for the SINUMERIK 840D sl control system. The kinds and types of the definition of variables for the control system under discussion described. On the example of the longitudinal cutting cycle, parametric programming possibilities are shown. The program’s code and its implementation in the control system is described in detail. The principle of parametric programming in a high-level language is also explained.

  12. Stability analysis of machine tool spindle under uncertainty

    Directory of Open Access Journals (Sweden)

    Wei Dou

    2016-05-01

    Full Text Available Chatter is a harmful machining vibration that occurs between the workpiece and the cutting tool, usually resulting in irregular flaw streaks on the finished surface and severe tool wear. Stability lobe diagrams could predict chatter by providing graphical representations of the stable combinations of the axial depth of the cut and spindle speed. In this article, the analytical model of a spindle system is constructed, including a Timoshenko beam rotating shaft model and double sets of angular contact ball bearings with 5 degrees of freedom. Then, the stability lobe diagram of the model is developed according to its dynamic properties. The Monte Carlo method is applied to analyse the bearing preload influence on the system stability with uncertainty taken into account.

  13. Design of piezo-based AVC system for machine tool applications

    Science.gov (United States)

    Aggogeri, F.; Al-Bender, F.; Brunner, B.; Elsaid, M.; Mazzola, M.; Merlo, A.; Ricciardi, D.; de la O Rodriguez, M.; Salvi, E.

    2013-03-01

    The goal of machine tools for Ultra High Precision Machining is to guarantee high specified performances and to maintain them over life cycle time. In this paper the design of an innovative mechatronic subsystem (platform) for Active Vibration Control (AVC) of Ultra High Precision micromilling Machines is presented. The platform integrates piezoelectric stack actuators and a novel sensor concept. During the machining process (e.g. milling), the contact between the cutting tool and the workpiece surface at the tool tip point generates chattering vibrations. Any vibration is recorded on the workpiece surface, directly affecting its roughness. Consequently, uncontrolled vibrations lead to poor surface finishing, unacceptable in high precision milling. The proposed Smart Platform aims to improve the surface finishing of the workpiece exploiting a broadband AVC strategy. The paper describes the steps throughout the design phase of the platform, beginning from the actuator/sensor criteria selection taking into account both performance and durability. The novel actuation principle and mechanism and the related FE analysis are also presented. Finally, an integrated mechatronic model able to predict in closed-loop the active damping and vibration-suppression capability of the integrated system is presented and simulation results are discussed.

  14. CIMT 2003--An attractive gala of world machine tool industry

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    @@ With the support of the Chinese Government and through close cooperation with related machine tool associations from all countries of the world, the China Machine Tool & Tool Builders' Association(CMTBA) has successfully hosted seven times of the China International Machine Tool Show(CIMT). With expanding scales and exhibition of more advanced products, CIMT has become the largest and best- known international machine tool exhibition in China. Domestic and overseas machine tool manufacturers consider CIMT an important venue to demonstrate their new products, conduct technological exchanges, promote trade and seek cooperative and joint venture partners. The 8th China International Machine Tool Show, also known as CIMT 2003, will be held at the China International Exhibition Center in Beijing on April 16 - 22 next year. The organizer of CIMT 2003 has started the work of inviting domestic and overseas machine tool manufacturers to attend the grand exhibition.

  15. Research on impacts of mechanical vibrations on the production machine to its rate of change of technical state

    Directory of Open Access Journals (Sweden)

    Štefánia Salokyová

    2016-06-01

    Full Text Available The article observes the amount of vibration on the bearing house of a turning lathe selected in advance through the change of the revolutions per minute and the thickness of the removed material in frontal type of lathe processing. Increase in mechanical vibration values depending on the value of nominal thickness of splinter was observed during changing technological parameters of the drilling process as a consequence of rotation speed of the motor. The vibration acceleration amplitude course changes depending on the frequencies are evaluated together for 400, 800 and 1200 motor r/min. A piezoelectric sensor of the type 4507B-004 from the Brüel & Kjaer Company was used for monitoring the frequency analysis of the vibration, which was attached to the bearing house of the lathe TOS SV 18RB. The vibration signal measured during the processing and during the time period is transformed through the means of a quick Fourier transformation to the frequency spectrum in the range of 3.0–10.0 kHz. Measured values of vibration acceleration amplitude were processed and evaluated by the SignalExpress software. Graphical abstract Unwanted vibration in machine tools like lathe is one of the main problems as it affects the quality of the machined parts and tool life and creates noise during machining operation. Bearings are of paramount importance to almost all forms of rotating machinery and are the most common among machine elements. The article describes in more detail the issue of vibrations created when machining the material by lathe turning. It also includes execution, experiment evaluation in this field, and comparison of measured vibrations’ acceleration amplitude values according to the standards.

  16. ANALYTICAL MODEL OF CALCULUS FOR INFLUENCE THE TRANSLATION GUIDE WEAR OVER THE MACHINING ACCURACY ON THE MACHINE TOOL

    Directory of Open Access Journals (Sweden)

    Ivona PETRE

    2010-10-01

    Full Text Available The wear of machine tools guides influences favorably to vibrations. As a result of guides wear, the initial trajectory of cutting tools motion will be modified, the generating dimensional accuracy discrepancies and deviations of geometrical shape of the work pieces. As it has already been known, the wear of mobile and rigid guides is determined by many parameters (pressure, velocity, friction length, lubrication, material. The choice of one or another analytic model and/or the experimental model of the wear is depending by the working conditions, assuming that the coupling material is known.The present work’s goal is to establish an analytic model of calculus showing the influence of the translation guides wear over the machining accuracy on machine-tools.

  17. Contribution à la compensation active des vibrations des machines électriques

    OpenAIRE

    Granjon, Pierre

    2000-01-01

    This work is devoted to elaborate an active control system of rotating machine vibrations. It is based on additional currents supplying the stator coils of the machine. They generate radial forces on the stator frame,and finally create additional vibrations which interact with the machine ones. Therefore, the aim of this system is to process the optimal value of the input currents, in order to minimize the vibration signals power measured on the stator frame by several accelerometers.First, t...

  18. Keeping you safe by making machine tools safe

    CERN Multimedia

    2012-01-01

    CERN’s third safety objective for 2012 concerns the safety of equipment - and machine tools in particular.   There are three prerequisites for ensuring that a machine tool can be used safely: ·      the machine tool must comply with Directive 2009/104/EC, ·      the layout of the workshop must be compliant, and ·      everyone who uses the machine tool must be trained. Provided these conditions are met, the workshop head can grant authorisation to use the machine tool. To fulfil this objective, an inventory of the machine tools must be drawn up and the people responsible for them identified. The HSE Unit's Safety Inspection Service produces compliance reports for the machine tools. In order to meet the third objective set by the Director-General, the section has doubled its capacity to carry out inspections: ...

  19. Dynamics of Vibration Machine with Air Flow Excitation and Restrictions on Phase Coordinates

    OpenAIRE

    Vība, J; Beresņevičs, V; Štāls, L; Eiduks, M; Kovals, E.; Kruusmaa, M.

    2010-01-01

    The objective of presented article is to show possibilities of practical use of air or liquid flow in vibration engineering. Dynamics of vibration machine with constant air or liquid flow excitation is considered. In the first part vibration motion of the machine working head under constant air or liquid flow velocity excitation is investigated. The main idea is to find out optimal control law for variation of additional surface area of vibrating object within limits. The criterion of optimiz...

  20. Influence of Process and Machine tool on tolerance

    DEFF Research Database (Denmark)

    De Chiffre, Leonardo

    This note gives a summary of how the process and the machine tool can influence the geometrical tolerances. The note concerns cutting processes and machine tools but many of the considerations can be transferred directly to other types of manufacturing process and machines....

  1. Study on electroplating technology of diamond tools for machining hard and brittle materials

    Science.gov (United States)

    Cui, Ying; Chen, Jian Hua; Sun, Li Peng; Wang, Yue

    2016-10-01

    With the development of the high speed cutting, the ultra-precision machining and ultrasonic vibration technique in processing hard and brittle material , the requirement of cutting tools is becoming higher and higher. As electroplated diamond tools have distinct advantages, such as high adaptability, high durability, long service life and good dimensional stability, the cutting tools are effective and extensive used in grinding hard and brittle materials. In this paper, the coating structure of electroplating diamond tool is described. The electroplating process flow is presented, and the influence of pretreatment on the machining quality is analyzed. Through the experimental research and summary, the reasonable formula of the electrolyte, the electroplating technologic parameters and the suitable sanding method were determined. Meanwhile, the drilling experiment on glass-ceramic shows that the electroplating process can effectively improve the cutting performance of diamond tools. It has laid a good foundation for further improving the quality and efficiency of the machining of hard and brittle materials.

  2. Vibration Prediction Method of Electric Machines by using Experimental Transfer Function and Magnetostatic Finite Element Analysis

    Science.gov (United States)

    Saito, A.; Kuroishi, M.; Nakai, H.

    2016-09-01

    This paper concerns the noise and structural vibration caused by rotating electric machines. Special attention is given to the magnetic-force induced vibration response of interior-permanent magnet machines. In general, to accurately predict and control the vibration response caused by the electric machines, it is inevitable to model not only the magnetic force induced by the fluctuation of magnetic fields, but also the structural dynamic characteristics of the electric machines and surrounding structural components. However, due to complicated boundary conditions and material properties of the components, such as laminated magnetic cores and varnished windings, it has been a challenge to compute accurate vibration response caused by the electric machines even after their physical models are available. In this paper, we propose a highly-accurate vibration prediction method that couples experimentally-obtained discrete structural transfer functions and numerically-obtained distributed magnetic-forces. The proposed vibration synthesis methodology has been applied to predict vibration responses of an interior permanent magnet machine. The results show that the predicted vibration response of the electric machine agrees very well with the measured vibration response for several load conditions, for wide frequency ranges.

  3. FFT and Wavelet-Based Analysis of the Influence of Machine Vibrations on Hard Turned Surface Topographies

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    With hard turning, which is an attractive alternative to existing grinding processes, surface quality is of great importance. Signal processing techniques were used to relate workpiece surface topography to the dynamic behavior of the machine tool. Spatial domain frequency analyses based on fast Fourier transform were used to analyze the tool behavior. Wavelet reconstruction was used for profile filtering. The results show that machine vibration remarkably affects the surface topography at small feed rates, but has negligible effect at high feed rates. The analyses also show how to control the surface quality during hard turning.

  4. THE MACHINING OF HARDENED CARBON STEELS BY COATED CUTTING TOOLS

    Directory of Open Access Journals (Sweden)

    Yusuf ŞAHİN

    2001-02-01

    Full Text Available The investigation of machining AISI 1050 carbon steels hardened to the 60 HRC hardness was carried out to determine the tool life and wear behaviour of the various cutting tools under different conditions. These experiments were conducted at using coated ceramic cutting tools and carbide cutting tools. The experimental results showed that the coated ceramic tools exhibited better performance than those of the coated carbide tools when machining the hardened steels. Moreover, wear behaviour of cutting tools were investigated in a scanning electron microscope. Electron microscopic examination also indicated that flank wear, thermal cracks on the tool nose combined with the nose deformation on the tools were responsible for the wear behaviour of the ceramic tools. For the carbide tools, however, removal of coated material from the substrate tool and combined with the crater wear were effective for the machining the hardened steel.

  5. USSR Report, Machine Tools and Metalworking Equipment, No. 6

    Science.gov (United States)

    2007-11-02

    operators, forsee shortages of equipment for individual machine groups, or take into account wastage due to nonideal manufacturing condipions. Let us...manufacture, chemical and petroleum machine building, and machine building for light industry, the food industry, and household appliance manufacture...Building for Light and Food Industry and Household Appliances for a group of tool shops at machine-building plants in Kiev, Vinnintsa, and Poltava

  6. Envelope analysis of rotating machine vibrations in variable speed conditions: A comprehensive treatment

    Science.gov (United States)

    Abboud, D.; Antoni, J.; Sieg-Zieba, S.; Eltabach, M.

    2017-02-01

    Nowadays, the vibration analysis of rotating machine signals is a well-established methodology, rooted on powerful tools offered, in particular, by the theory of cyclostationary (CS) processes. Among them, the squared envelope spectrum (SES) is probably the most popular to detect random CS components which are typical symptoms, for instance, of rolling element bearing faults. Recent researches are shifted towards the extension of existing CS tools - originally devised in constant speed conditions - to the case of variable speed conditions. Many of these works combine the SES with computed order tracking after some preprocessing steps. The principal object of this paper is to organize these dispersed researches into a structured comprehensive framework. Three original features are furnished. First, a model of rotating machine signals is introduced which sheds light on the various components to be expected in the SES. Second, a critical comparison is made of three sophisticated methods, namely, the improved synchronous average, the cepstrum prewhitening, and the generalized synchronous average, used for suppressing the deterministic part. Also, a general envelope enhancement methodology which combines the latter two techniques with a time-domain filtering operation is revisited. All theoretical findings are experimentally validated on simulated and real-world vibration signals.

  7. Design principles of metal-cutting machine tools

    CERN Document Server

    Koenigsberger, F

    1964-01-01

    Design Principles of Metal-Cutting Machine Tools discusses the fundamentals aspects of machine tool design. The book covers the design consideration of metal-cutting machine, such as static and dynamic stiffness, operational speeds, gearboxes, manual, and automatic control. The text first details the data calculation and the general requirements of the machine tool. Next, the book discusses the design principles, which include stiffness and rigidity of the separate constructional elements and their combined behavior under load, as well as electrical, mechanical, and hydraulic drives for the op

  8. Analysis of vibration reduction level in an 8/6 switched reluctance machine by active vibration cancellation

    Institute of Scientific and Technical Information of China (English)

    Xu LIU; Zai-ping PAN; Z.Q. ZHU

    2010-01-01

    This paper proposes an analytical model for predicting the maximum vibration reduction level in a four-phase 8/6switched reluctance machine(SRM)by employing active vibration cancellation(AVC),one of the most effective and convenient methods for reducing the vibration and acoustic noise produced by SRMs.Based on the proposed method,the factors that influence the vibration reduction level are analyzed in detail.The relationships between vibration and noise reduction levels at resonance frequency and rotor speed are presented.Moreover,it is shown that a large damping factor will lead to smaller vibration reduction level with AVC while,in contrast,a large resonance frequency will increase the vibration reduction level.Both finite element analyses and experiments were carried out on a prototype 8/6 SRM to validate the proposed method.

  9. DRIVE AND CONTROL OF VIRTUAL-AXIS NC MACHINE TOOLS

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    The structure features and driving modes of virtual-axis NC machine tools are studied.Accor- ding to different application requirements,the three-axis control method,the five-axis control method and the six-freedom control method are put forward.These results lay a foundation for the product development of the virtual-axis NC machine tools.

  10. Thermal Analysis for Condition Monitoring of Machine Tool Spindles

    Science.gov (United States)

    Clough, D.; Fletcher, S.; Longstaff, A. P.; Willoughby, P.

    2012-05-01

    Decreasing tolerances on parts manufactured, or inspected, on machine tools increases the requirement to have a greater understanding of machine tool capabilities, error sources and factors affecting asset availability. Continuous usage of a machine tool during production processes causes heat generation typically at the moving elements, resulting in distortion of the machine structure. These effects, known as thermal errors, can contribute a significant percentage of the total error in a machine tool. There are a number of design solutions available to the machine tool builder to reduce thermal error including, liquid cooling systems, low thermal expansion materials and symmetric machine tool structures. However, these can only reduce the error not eliminate it altogether. It is therefore advisable, particularly in the production of high value parts, for manufacturers to obtain a thermal profile of their machine, to ensure it is capable of producing in tolerance parts. This paper considers factors affecting practical implementation of condition monitoring of the thermal errors. In particular is the requirement to find links between temperature, which is easily measureable during production and the errors which are not. To this end, various methods of testing including the advantages of thermal images are shown. Results are presented from machines in typical manufacturing environments, which also highlight the value of condition monitoring using thermal analysis.

  11. Research on steel-fibber polymer concrete machine tool structure

    Institute of Scientific and Technical Information of China (English)

    XU Ping; YU Ying-hua

    2008-01-01

    Researched on the design and manufacturing of machine tool bed made by Steel-fibber Polymer Concrete(SFPC),which analyzed the static,dynamic and thermal performances of the bed.The results of study prove that machine tool bed made with SFPC is much more superiority than made in cast iron in dynamic and thermal performances,and is more superiority then made in Polymer Concrete (PC) in static performances.It can be concluded that the static,dynamic and thermal properties of machine tool can be improved by manufacturing machine tool bed with SFPC.Also SFPC machine tool bed posses some other advantages in the following: short development time,simple production process,reducing cost cost,saving energy,iron and steel.

  12. Research on steel-fibber polymer concrete machine tool structure

    Institute of Scientific and Technical Information of China (English)

    XU Ping; YU Ying-hua

    2008-01-01

    Researched on the design and manufacturing of machine tool bed made by Steel-fibber Polymer Concrete(SFPC), which analyzed the static, dynamic and thermal performances of the bed. The results of study prove that machine tool bed made with SFPC is much more superiority than made in cast iron in dynamic and thermal perform-ances, and is more superiority then made in Polymer Concrete (PC) in static perform-ances. It can be concluded that the static, dynamic and thermal properties of machine tool can be improved by manufacturing machine tool bed with SFPC. Also SFPC machine tool bed posses some other advantages in the following: short development time, simple pro-duction process, reducing cost cost, saving energy, iron and steel.

  13. 基于Android的机床在线无线振动监测仪研制%Development of Wireless Vibration Instrument for Machine Tool Online Based on Android

    Institute of Scientific and Technical Information of China (English)

    郑美茹

    2016-01-01

    In order to protect the safety of operators and to prevent leakage of cutting fluid, modern numercial control ( NC) ma⁃chine tool is all installed with protective cover, which makes difficulty for wiring and point allocation of sensors for online monitoring on site. Aiming at the existing problems of traditional online vibration sensor such as high power consumption, difficult in wiring and point allocation on the sealed protective cover, a wireless vibration instrument based on the Android system and CC2540 single chip micro⁃computer was developed. The wireless transmission and online parametric setup of measurement, real time data display and storage functions were achieved by the measuring instrument combined with Android system and Bluetooth. The wiring problem of sensors was effectively solved by wireless transmission. The pretreatment and collection of vibration signal were completed by the measuring modules with CC2540 as central control unit, which was embedded with Bluetooth modules at low power consumption and the Android system to implement the communication of full⁃duplex communication, to save data in TF card or in cloud hosting. The actual tests show that the instrument can be used to accurately measure the vibration acceleration signal, and can be used to accurately send and receive data through the Bluetooth modules and Android mobile phone, which is convenient, simple operation and also good in application prospect. It provides reference for development of other new types of wireless measuring instrument.%为保护操作者的安全、防止切削液的外漏等,现代数控机床都安装了防护罩壳,这给现场在线监测的传感器布线、布点造成了困难。针对传统有线振动传感器在密闭防护罩壳内存在布线、布点困难和功耗高等问题,研制基于Android系统和CC2540单片机的无线振动测量仪。通过Android 系统和蓝牙实现了仪器的在线参数设置和无线传输、实时数

  14. PERFORMANCE OF COATED CUTTING TOOLS IN MACHINING HARDENED STEEL

    Directory of Open Access Journals (Sweden)

    K.Subramanyam,

    2010-10-01

    Full Text Available This paper deals with the study of the performance of coated tools in machining hardening steel under dry conditions. This paper involves of machining AISI 4340 hardened steel using coated carbide tools is studied using full factorial experiments. Many parameters influence the quality of the products in hard turning process. The objective of this study is on the effect of the cutting conditions such as cutting velocity, feed, and depth of cut on the surface finish in machining AISI 4340 hardened steel. Machining of hardened steels has become an important manufacturing process, particularly in the automotive and bearing industries.

  15. Study of on-machine error identification and compensation methods for micro machine tools

    Science.gov (United States)

    Wang, Shih-Ming; Yu, Han-Jen; Lee, Chun-Yi; Chiu, Hung-Sheng

    2016-08-01

    Micro machining plays an important role in the manufacturing of miniature products which are made of various materials with complex 3D shapes and tight machining tolerance. To further improve the accuracy of a micro machining process without increasing the manufacturing cost of a micro machine tool, an effective machining error measurement method and a software-based compensation method are essential. To avoid introducing additional errors caused by the re-installment of the workpiece, the measurement and compensation method should be on-machine conducted. In addition, because the contour of a miniature workpiece machined with a micro machining process is very tiny, the measurement method should be non-contact. By integrating the image re-constructive method, camera pixel correction, coordinate transformation, the error identification algorithm, and trajectory auto-correction method, a vision-based error measurement and compensation method that can on-machine inspect the micro machining errors and automatically generate an error-corrected numerical control (NC) program for error compensation was developed in this study. With the use of the Canny edge detection algorithm and camera pixel calibration, the edges of the contour of a machined workpiece were identified and used to re-construct the actual contour of the work piece. The actual contour was then mapped to the theoretical contour to identify the actual cutting points and compute the machining errors. With the use of a moving matching window and calculation of the similarity between the actual and theoretical contour, the errors between the actual cutting points and theoretical cutting points were calculated and used to correct the NC program. With the use of the error-corrected NC program, the accuracy of a micro machining process can be effectively improved. To prove the feasibility and effectiveness of the proposed methods, micro-milling experiments on a micro machine tool were conducted, and the results

  16. Volumetric verification of multiaxis machine tool using laser tracker.

    Science.gov (United States)

    Aguado, Sergio; Samper, David; Santolaria, Jorge; Aguilar, Juan José

    2014-01-01

    This paper aims to present a method of volumetric verification in machine tools with linear and rotary axes using a laser tracker. Beyond a method for a particular machine, it presents a methodology that can be used in any machine type. Along this paper, the schema and kinematic model of a machine with three axes of movement, two linear and one rotational axes, including the measurement system and the nominal rotation matrix of the rotational axis are presented. Using this, the machine tool volumetric error is obtained and nonlinear optimization techniques are employed to improve the accuracy of the machine tool. The verification provides a mathematical, not physical, compensation, in less time than other methods of verification by means of the indirect measurement of geometric errors of the machine from the linear and rotary axes. This paper presents an extensive study about the appropriateness and drawbacks of the regression function employed depending on the types of movement of the axes of any machine. In the same way, strengths and weaknesses of measurement methods and optimization techniques depending on the space available to place the measurement system are presented. These studies provide the most appropriate strategies to verify each machine tool taking into consideration its configuration and its available work space.

  17. Dynamic Interaction between Machine, Tool, and Substrate in Bobbin Friction Stir Welding

    Directory of Open Access Journals (Sweden)

    Mohammad K. Sued

    2016-01-01

    Full Text Available The bobbin friction stir welding (BFSW process has benefits for welding aluminium alloy 6082-T6 in the boat-building industry. However this alloy is difficult to weld in the thin state. There are a large number of process variables and covert situational factors that affect weld quality. This paper investigates how tool holder and machine-type affect BFSW weld quality of 4 mm Al6082-T6. The variables were tool features (three types, machine-controller type (two types, and tool holder (fixed versus floating. Fourier analysis was performed on motor spindle current to determine the frequency response of the machine. An interaction was found between the computer numerical control (CNC, the degrees of freedom of the tool holder, and the substrate (workpiece. The conventional idea that the welding tool has a semisteady interaction with the substrate is not supported. Instead the interaction is highly dynamic, and this materially affects the weld quality. Specific vibrational interactions are associated with poor welding. The CNC machine-type also emerges as a neglected variable that needs to be given attention in the selection of process parameters. Although compliance in the tool holder might seem useful, it is shown to have negative consequences as it introduces tool positioning problems.

  18. A Method for Design of Modular Reconfigurable Machine Tools

    Directory of Open Access Journals (Sweden)

    Zhengyi Xu

    2017-02-01

    Full Text Available Presented in this paper is a method for the design of modular reconfigurable machine tools (MRMTs. An MRMT is capable of using a minimal number of modules through reconfiguration to perform the required machining tasks for a family of parts. The proposed method consists of three steps: module identification, module determination, and layout synthesis. In the first step, the module components are collected from a family of general-purpose machines to establish a module library. In the second step, for a given family of parts to be machined, a set of needed modules are selected from the module library to construct a desired reconfigurable machine tool. In the third step, a final machine layout is decided though evaluation by considering a number of performance indices. Based on this method, a software package has been developed that can design an MRMT for a given part family.

  19. Implementing Machine Learning in the PCWG Tool

    Energy Technology Data Exchange (ETDEWEB)

    Clifton, Andrew; Ding, Yu; Stuart, Peter

    2016-12-13

    The Power Curve Working Group (www.pcwg.org) is an ad-hoc industry-led group to investigate the performance of wind turbines in real-world conditions. As part of ongoing experience-sharing exercises, machine learning has been proposed as a possible way to predict turbine performance. This presentation provides some background information about machine learning and how it might be implemented in the PCWG exercises.

  20. Development of Machine Learning Tools in ROOT

    Science.gov (United States)

    Gleyzer, S. V.; Moneta, L.; Zapata, Omar A.

    2016-10-01

    ROOT is a framework for large-scale data analysis that provides basic and advanced statistical methods used by the LHC experiments. These include machine learning algorithms from the ROOT-integrated Toolkit for Multivariate Analysis (TMVA). We present several recent developments in TMVA, including a new modular design, new algorithms for variable importance and cross-validation, interfaces to other machine-learning software packages and integration of TMVA with Jupyter, making it accessible with a browser.

  1. Rotary ultrasonic elliptical machining for side milling of CFRP: tool performance and surface integrity.

    Science.gov (United States)

    Geng, Daxi; Zhang, Deyuan; Xu, Yonggang; He, Fengtao; Liu, Dapeng; Duan, Zuoheng

    2015-05-01

    The rotary ultrasonic elliptical machining (RUEM) has been recognized as a new effective process to machining circular holes on CFRP materials. In CFRP face machining, the application of grinding tools is restricted for the tool clogging and the machined surface integrity. In this paper, we proposed a novel approach to extend the RUEM process to side milling of CFRP for the first time, which kept the effect of elliptical vibration in RUEM. The experiment apparatus was developed, and the preliminary experiments were designed and conducted, with comparison to conventional grinding (CG). The experimental results showed that when the elliptical vibration was applied in RUEM, a superior cutting process can be obtained compared with that in CG, including providing reduced cutting forces (2-43% decrement), an extended tool life (1.98 times), and improved surface integrity due to the intermittent material removal mechanism and the excellent chip removal conditions achieved in RUEM. It was concluded that the RUEM process is suitable to mill flat surface on CFRP composites.

  2. Determination of Dynamic Characteristics of the Frame Bearing Structures of the Vibrating Separating Machines

    Science.gov (United States)

    Piven, V. V.; Umanskaya, O. L.

    2016-08-01

    Within the vibrating separating machines the vibration displacement of the members is transferred to a frame bearing structure, and over it the movement is transferred again to the suspension brackets of the sieve separating surfaces and to the foundation, on which the machine is fixed. The forced oscillations of the sieve separating surfaces ensure the separation process, and the vibration, transferred from the frame structure, disturbs this process. It is necessary to ensure the vibration displacement of the separating surfaces within the fixed limitations by means of optimal design of the frame bearing surfaces. The aim of the work is to decrease adverse vibrations towards the technological separation process. The calculated and graphical relations, acquired according to the presented methods, enable to estimate the influence of various structure solutions on vibration displacements of the structure elements at the stage of design.

  3. Job Grading Standard for Machine Tool Operator, WG-3431.

    Science.gov (United States)

    Civil Service Commission, Washington, DC. Bureau of Policies and Standards.

    The standard covers nonsupervisory work involved in the set up, adjustment, and operation of conventional machine tools to perform machining operations in the manufacture and repair of castings, forgings, or parts from raw stock made of various metals, metal alloys, and other materials. A general description of the job at both the WG-8 and WG-9…

  4. Forbidden Zones for Numerically-Controlled Machine Tools

    Science.gov (United States)

    Philpot, D.

    1986-01-01

    Computer-controlled machine tool prevented from striking and damaging protruding members on workpiece by creating forbidden zone in control program. With aid of computer graphics, tool profile and coordinates of forbidden zone digitized and stored in computer memory as part of tool path.

  5. Increasing Machine Tool Productivity with High Pressure Cryogenic Coolant Flow

    Science.gov (United States)

    1992-05-01

    tool change time and cost for the three strategies. " Item 4 shows the Tool/Machine Cost Ratios ( TIM Ratio) for the various strategies and tool...0.; and Tharp , M. J. Chip breaking on uranium alloy. Oak Ridge Y-12 Plant, Union Carbide Corp., Oak Ridge, TN. September 1987, p. 16. 25. Ringler, A

  6. A mechanistic ultrasonic vibration amplitude model during rotary ultrasonic machining of CFRP composites.

    Science.gov (United States)

    Ning, Fuda; Wang, Hui; Cong, Weilong; Fernando, P K S C

    2017-04-01

    Rotary ultrasonic machining (RUM) has been investigated in machining of brittle, ductile, as well as composite materials. Ultrasonic vibration amplitude, as one of the most important input variables, affects almost all the output variables in RUM. Numerous investigations on measuring ultrasonic vibration amplitude without RUM machining have been reported. In recent years, ultrasonic vibration amplitude measurement with RUM of ductile materials has been investigated. It is found that the ultrasonic vibration amplitude with RUM was different from that without RUM under the same input variables. RUM is primarily used in machining of brittle materials through brittle fracture removal. With this reason, the method for measuring ultrasonic vibration amplitude in RUM of ductile materials is not feasible for measuring that in RUM of brittle materials. However, there are no reported methods for measuring ultrasonic vibration amplitude in RUM of brittle materials. In this study, ultrasonic vibration amplitude in RUM of brittle materials is investigated by establishing a mechanistic amplitude model through cutting force. Pilot experiments are conducted to validate the calculation model. The results show that there are no significant differences between amplitude values calculated by model and those obtained from experimental investigations. The model can provide a relationship between ultrasonic vibration amplitude and input variables, which is a foundation for building models to predict other output variables in RUM.

  7. Setting of angles on machine tools speeded by magnetic protractor

    Science.gov (United States)

    Vale, L. B.

    1964-01-01

    An adjustable protractor facilitates transference of angles to remote machine tools. It has a magnetic base incorporating a beam which can be adjusted until its shadow coincides with an image on the screen of a projector.

  8. Research on Visual Virtual Design Platform for NC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    HU Rufu; CHEN Xiaoping; SUN Qinghong

    2006-01-01

    The fundamental ideas on building the collaborative design platform of virtual visualization for NC machine tools are introduced. The platform is based on the globally shared product model conforming to the STEP Standard, and used PDM system to integrate and encapsulate CAD/CAE and other application software for the product development. The platform also integrated the expert system of NC machine tools design, analysis and estimation. This expert system utilized fuzzy estimation principle to evaluate the design and simulation analysis results and make decisions. The platform provides the collaborative intelligent environment for the design of virtual NC machine tools prototype aiming at integrated product design team. It also supports the customized development of NC machine tools.

  9. Intelligent machine tools. Kosaku kikai no intelligent ka

    Energy Technology Data Exchange (ETDEWEB)

    Moriwaki, T. (Kobe Univ., Kobe (Japan). Faculty of Engineering)

    1993-12-05

    A background of the trend to equip machine tools with intelligence is reviewed and the outline of intelligent machine tools that are now in the process of research and development is surveyed. The flexible manufacturing system (FMS) that was born in the process of automation of machine manufacturing has been proved, in fact, inflexible in the hierarchical structure of information system. This directs attention of transferring to an autonomous and dispersed manufacturing system. In the system, structural components such as machine tools are required to be highly intelligent enough to produce things, while deciding their will autonomously according to their own criteria in cooperation with other components and attempting to optimize the system. The hardware of intelligent machine tools consists of an interface part to intermediate between machines and computers or human, a core system of center of intelligence, and a machine tool part responsible to process things actually. As to processing of information and movement, they consist of processing parts of pre-process, in-process and post-process. A brief introduction is given on their basic functions and on the present state of related researches. 8 refs., 4 figs.

  10. Non-contact measurement and analysis of machine tool spindles

    OpenAIRE

    Clough, David A; Fletcher, Simon; Longstaff, Andrew P.

    2010-01-01

    Increasing demand on the manufacturing industry to produce tighter tolerance parts means it is\\ud necessary to gain a greater understanding of machine tool capabilities and error sources. A significant source of machine tool errors is down to spindle inaccuracies and performance, leading to part scrapping. Catastrophic spindle failure brings production to a standstill until a new spindle can be procured and installed, resulting in lost production time.\\ud This project aims to assess the effec...

  11. Improvement of Electrochemical Machining Accuracy by Using Dual Pole Tool

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Electrochemical machining (ECM) is one of the best al ternatives for producing complex shapes in advanced materials used in aircraft a nd aerospace industries. However, the reduction of the stray material removal co ntinues to be major challenges for industries in addressing accuracy improvement . This study presents a method of improving machining accuracy in ECM by using a dual pole tool with a metallic bush outside the insulated coating of a cathode tool. The bush is connected with anode and so the el...

  12. THE DESIGN AND ANALYSIS OF VIBRATION STRUCTURE OF VERTICAL DYNAMIC BALANCING MACHINE

    Institute of Scientific and Technical Information of China (English)

    LiDinggen; CaoJiguang; WangJtmwen; ChenChuanyao

    2004-01-01

    A new type of vibration structure (i.e. supporting system, called swing frame customarily) of vertical dynamic balancing machine has been designed, which is based on an analysis for the swing frame of a traditional double-plane vertical dynamic balancing machine. The static unbalance and couple unbalance can be effectively separated by using the new dynamic balancing machine with the new swing frame. By building the dynamics model, the advantages of the new structure are discussed in detail. The modal and harmonic response are analyzed by using the ANSYS7.0. By comparing the finite element modal analysis with the experimental modal analysis, the natural frequencies and vibration modes are found. There are many spring boards in the new swing frame. Their stiffnesses are different and assorted with each other. Furthermore, there are three sensors on the measuring points. Therefore, the new dynamic balancing machine can measure static unbalance and coupling unbalance directly, and the interaction between them is faint. The result shows that the new vertical dynamic balancing machine is suitable for inertial measurement of flying objects, and can overcome the shortcomings of traditional double-plane vertical dynamic balancing machines, which the effect of plane-separation is inferior. The vertical dynamic balancing machine with the new vibration structure can find wide application in the future. The modelling and analysis of the new vibration structure will provide theoretical basis and practical experience for designing new-type vertical dynamic balancing machines.

  13. Mississippi Curriculum Framework for Machine Tool Operation/Machine Shop (Program CIP: 48.0503--Machine Shop Assistant). Secondary Programs.

    Science.gov (United States)

    Mississippi Research and Curriculum Unit for Vocational and Technical Education, State College.

    This document, which reflects Mississippi's statutory requirement that instructional programs be based on core curricula and performance-based assessment, contains outlines of the instructional units required in local instructional management plans and daily lesson plans for machine tool operation/machine shop I and II. Presented first are a…

  14. Case study of virtual reality in CNC machine tool exhibition

    Directory of Open Access Journals (Sweden)

    Kao Yung-Chou

    2017-01-01

    Full Text Available Exhibition and demonstration are generally used in the promotion and sale-assistance of manufactured products. However, the transportation cost of the real goods from the vender factory to the exposition venue is generally expensive for huge and heavy commodity. With the advancement of computing, graphics, mobile apps, and mobile hardware the 3D visibility technology is getting more and more popular to be adopted in visual-assisted communication such as amusement games. Virtual reality (VR technology has therefore being paid great attention in emulating expensive small and/or huge and heavy equipment. Virtual reality can be characterized as 3D extension with Immersion, Interaction and Imagination. This paper was then be focused on the study of virtual reality in the assistance of CNC machine tool demonstration and exhibition. A commercial CNC machine tool was used in this study to illustrate the effectiveness and usability of using virtual reality for an exhibition. The adopted CNC machine tool is a large and heavy mill-turn machine with the width up to eleven meters and weighted about 35 tons. A head-mounted display (HMD was attached to the developed VR CNC machine tool for the immersion viewing. A user can see around the 3D scene of the large mill-turn machine and the operation of the virtual CNC machine can be actuated by bare hand. Coolant was added to demonstrate more realistic operation while collision detection function was also added to remind the operator. The developed VR demonstration system has been presented in the 2017 Taipei International Machine Tool Show (TIMTOS 2017. This case study has shown that young engineers and/or students are very impressed by the VR-based demonstration while elder persons could not adapt themselves easily to the VR-based scene because of eyesight issues. However, virtual reality has successfully being adopted and integrated with the CNC machine tool in an international show. Another machine tool on

  15. Bi-objective robust optimization of machined surface quality and productivity under vibrations limitation

    Directory of Open Access Journals (Sweden)

    Sahali M.A.

    2015-01-01

    Full Text Available In this contribution, a bi-objective robust optimization of cutting parameters, with the taking into account uncertainties inherent in the tool wear and the tool deflection for a turning operation is presented. In a first step, we proceed to the construction of substitution models that connect the cutting parameters to the variables of interest based on design of experiments. Our two objectives are the best machined surface quality and the maximum productivity under consideration of limitations related to the vibrations and the range of the three cutting parameters. Then, using the developed genetic algorithm that based on a robust evaluation mechanism of chromosomes by Monte-Carlo simulations, the influence and interest of the uncertainties integration in the machining optimization is demonstrated. After comparing the classical and robust Pareto fronts, A surface quality less efficient but robust can be obtained with the consideration of uncontrollable factors or uncertainties unlike that provides the deterministic and classical optimization for the same values of productivity.

  16. Electromechanical coupling model and analysis of transient behavior for inertial vibrating machines

    Institute of Scientific and Technical Information of China (English)

    HU Ji-yun; YU Cui-ping; YIN Xue-gang

    2004-01-01

    A mathematical model of electromechanical coupling system for a planar inertial vibrating machine is built by setting up dynamical equations of discrete systems with a matrix methodology proposed. The substance of the transient behavior of the machine is unveiled by analyzing the results of the computer simulation to the model, and new methods are presented for diminishing the transient amplitude of the vibrating machine and improving the transient behavior. The reliable mathematical model is provided for intelligent control of the transient behavior of the equipment.

  17. Diamond tool machining of materials which react with diamond

    Science.gov (United States)

    Lundin, Ralph L.; Stewart, Delbert D.; Evans, Christopher J.

    1992-01-01

    Apparatus for the diamond machining of materials which detrimentally react with diamond cutting tools in which the cutting tool and the workpiece are chilled to very low temperatures. This chilling halts or retards the chemical reaction between the workpiece and the diamond cutting tool so that wear rates of the diamond tool on previously detrimental materials are comparable with the diamond turning of materials which do not react with diamond.

  18. A Tool Path Generation Strategy for Sculptured Surfaces Machining

    Institute of Scientific and Technical Information of China (English)

    Chen Tao; Zhong Yifang; Zhou Ji

    2001-01-01

    This paper presents a strategy to generate interference-free tool paths for machiningsculptured surfaces. The strategy proposed here is first to determine the tool path topology. Thevalues of the step length and the path interval are then calculated based on the machining tolerancerequirements. After detecting and eliminating the tool interference, the interference-free tool path isgenerated. The effectiveness of the developed algorithm is demonstrated through simulation andactual cutting tests.

  19. Assisting the Tooling and Machining Industry to Become Energy Efficient

    Energy Technology Data Exchange (ETDEWEB)

    Curry, Bennett [Arizona Commerce Authority, Phoenix, AZ (United States)

    2016-12-30

    The Arizona Commerce Authority (ACA) conducted an Innovation in Advanced Manufacturing Grant Competition to support and grow southern and central Arizona’s Aerospace and Defense (A&D) industry and its supply chain. The problem statement for this grant challenge was that many A&D machining processes utilize older generation CNC machine tool technologies that can result an inefficient use of resources – energy, time and materials – compared to the latest state-of-the-art CNC machines. Competitive awards funded projects to develop innovative new tools and technologies that reduce energy consumption for older generation machine tools and foster working relationships between industry small to medium-sized manufacturing enterprises and third-party solution providers. During the 42-month term of this grant, 12 competitive awards were made. Final reports have been included with this submission.

  20. Accuracy Analysis and Calibration of Gantry Hybrid Machine Tool

    Institute of Scientific and Technical Information of China (English)

    唐晓强; 李铁民; 尹文生; 汪劲松

    2003-01-01

    The kinematic accuracy is a key factor in the design of parallel or hybrid machine tools. This analysis improved the accuracy of a 4-DOF (degree of freedom) gantry hybrid machine tool based on a 3-DOF planar parallel manipulator by compensating for various positioning errors. The machine tool architecture was described with the inverse kinematic solution. The control parameter error model was used to analyze the accuracy of the 3-DOF planar parallel manipulator and to develop a kinematic calibration method. The experimental results prove that the calibration method reduces the cutter nose errors from ±0.50 mm to ±0.03 mm for a horizontal movement of 600 mm by compensating for errors in the slider home position, the guide way distance and the extensible strut home position. The calibration method will be useful for similar types of parallel kinematic machines.

  1. Investigation of the Processing Parameters Impact on the Flexural Tool Vibrations While Drilling

    Directory of Open Access Journals (Sweden)

    I. I. Ivanov

    2015-01-01

    Full Text Available The paper considers an approach to analyze a dynamic stability of the drilling process in terms of tool flexibility. The proposed technique takes into consideration a regenerative effect leading to time delay in the dynamic system. This regenerative delay is the main source of arising dynamically unstable machining conditions. The paper describes a principle of emerging self-vibrations while cutting. It mentions the undesirable nature of transverse bending selfvibrations of tool, which cause a decreasing quality of the processed hole surface.The suggested approach consists in building a diagram of the drilling process stability for a tool model allowing only its flexural vibrations. The feature of the study is to describe tool dynamics using a finite element model based on the quadratic approximation of displacements for tool dynamics modeling. The assumption of an axial symmetry of drill geometry was discarded. The reduced model of tool was built taking into account two eigenvectors corresponding to tool bending. This model contains 2 degrees of freedom (DOF, which are, essentially, rotations of a drill tip. The technology of rigid multi-point constraints was used to connect those DOFs with solid finite element nodes. The system of delayed differential equations describing the reduced tool model dynamics was derived to estimate a dynamic stability of the drilling process. The Floquet theory is applied to build a stability diagram as a maximum multiplicator value versus a drill rotation rate. The presented diagram allows us to draw a conclusion that in the wide range of rotation frequencies transverse bending self- vibrations can be excited. The results obtained and the calculation technique may be used to choose the operation modes free from undesirable flexural self-vibrations of tool.The reported study was supported by RFBR within the framework of the research project ” mol_a”№ 14-08-31603 “Development of methods and algorithms for

  2. CONTRIBUTIONS TO THE STUDY OF THE VIBRATIONS FREQUENCY OF THE DRILL TOOL IN THE PROCESS OF MANUFACTURING THE BRONZE MATERIALS

    Directory of Open Access Journals (Sweden)

    Cosmin-Mihai MIRIŢOIU

    2013-05-01

    Full Text Available In this paper we present the experimental testings used to study the vibration of the drill tool, during the drilling of the bronze products. We have used the experimental setup presented in Miriţoiu (2013[1]. In this paper the vibrations are analyzed during the drilling on the universal lathe machines. The main purpose of to find a correlation between the cutting speed and the frequency of the vibration by using the experimental results and the regression analysis

  3. Structural Bionic Design of Machine Tool Structures

    Institute of Scientific and Technical Information of China (English)

    ZHAO Ling; WANG Ting; GUO Hong-liang; LI Guo-meng

    2011-01-01

    A structural bionic design process is systematically presented for lightweight mechanical structures. By mimicking biological excellent structural principles, the stiffening ribs of a machining table and a moving column were redesigned for better load-bearing efficiency. Finite element method(FEM) simulation and model experiments were carried out for performance verification, which showed the increase of structural static and dynamic performance. Structural bionic offers a new solution to change conventional structures for high specific stiffness.

  4. USSR Report: Machine Tools and Metalworking Equipment.

    Science.gov (United States)

    2007-11-02

    RABOCHAYA GAZETA, 29 Mar 85) AUTOMATED LINES AND AGGREGATED MACHINING SYSTEMS Flexible Production Systems in CEMA Countries Viewed (A. Poplekhin...Automation Equipment Eyed Flexible Module in Odessa ROBOTICS Leningrad Robotics Institute Heads CEMA Group (L. Chausov; PRAVDA, 4 Nov 85) Robot...FLEXIBLE PRODUCTION SYSTEMS IN CEMA COUNTRIES VIEWED Moscow SOTSIALISTICHESKAYA INDUSTRIYA in Russian 16 Mar 85 p 3 [Article by A. Poplekhin: "The Impact

  5. Static and Dynamic Performance Improvement of Conventional Computer Numerical Control Machine Tool Bed with Hybrid Welded Steel

    Directory of Open Access Journals (Sweden)

    S. S. Abuthakeer

    2011-01-01

    Full Text Available Problem statement: The advancements in machine tools to maximize the production by increasing spindle speeds have caused vibration in machine tools. The two functional requirements of machine tool bed for machine tools are high structural stiffness and high damping, which cannot be satisfied simultaneously if conventional metallic materials such as cast iron are employed. Hence there is a need to replace cast iron with alternate materials. Approach: The objective of this study is to improve the stiffness, natural frequency and damping capability of machine tool bed using a composite material containing welded steel and polymer concrete. Welded steel material has high stiffness but low damping and polymer concrete has high damping but low stiffness. So in this study, a machine tool bed made of sandwich structures of welded steel and polymer concrete is designed and manufactured. Modal and static analyses were conducted numerically and experimentally to determine the modal frequencies, damping ratio, deformation and strain. Results: The results at first mode showed that the natural frequency improved by 24.7% and damping ratio was 2.7 times higher than cast iron. The comparison of strain and deformation also showed significant improvement. Conclusion: This study proposed a hybrid welded steel bed as a replacement for cast iron as a machine tool bed material and the results showed that the static and dynamic characteristics were superior to cast iron.

  6. Characteristics of machined surface controlled by cutting tools and conditions in machining of brittle material

    Institute of Scientific and Technical Information of China (English)

    Yong-Woo KIM; Soo-Chang CHOI; Jeung-Woo PARK; Deug-Woo LEE

    2009-01-01

    One of the ultra-precision machining methods was adapted for brittle material as well as soft material by using multi-arrayed diamond tips and high speed spindle. Conventional machining method is too hard to control surface roughness and surface texture against brittle material because the particles of grinding tools are irregular size and material can be fragile. Therefore, we were able to design tool paths and machine controlled pattern on surface by multi-arrayed diamond tips with uniform size made in MEMS fabrication and high speed spindle, and the maximum speed was about 3×105 r/min. We defined several parameters that can affect the machining surface. Those were multi-array of diamond tips (n×n), speed of air spindle and feeding rate. The surface roughness and surface texture can be controlled by those parameters for micro machining.

  7. Synchronization of Two Self-Synchronous Vibrating Machines on an Isolation Frame

    Directory of Open Access Journals (Sweden)

    Chunyu Zhao

    2011-01-01

    Full Text Available This paper investigates synchronization of two self-synchronous vibrating machines on an isolation rigid frame. Using the modified average method of small parameters, we deduce the non-dimensional coupling differential equations of the disturbance parameters for the angular velocities of the four unbalanced rotors. Then the stability problem of synchronization for the four unbalanced rotors is converted into the stability problems of two generalized systems. One is the generalized system of the angular velocity disturbance parameters for the four unbalanced rotors, and the other is the generalized system of three phase disturbance parameters. The condition of implementing synchronization is that the torque of frequency capture between each pair of the unbalanced rotors on a vibrating machine is greater than the absolute values of the output electromagnetic torque difference between each pair of motors, and that the torque of frequency capture between the two vibrating machines is greater than the absolute value of the output electromagnetic torque difference between the two pairs of motors on the two vibrating machines. The stability condition of synchronization of the two vibrating machines is that the inertia coupling matrix is definite positive, and that all the eigenvalues for the generalized system of three phase disturbance parameters have negative real parts. Computer simulations are carried out to verify the results of the theoretical investigation.

  8. Hard turning micro-machine tool

    Science.gov (United States)

    DeVor, Richard E; Adair, Kurt; Kapoor, Shiv G

    2013-10-22

    A micro-scale apparatus for supporting a tool for hard turning comprises a base, a pivot coupled to the base, an actuator coupled to the base, and at least one member coupled to the actuator at one end and rotatably coupled to the pivot at another end. A tool mount is disposed on the at least one member. The at least one member defines a first lever arm between the pivot and the tool mount, and a second lever arm between the pivot and the actuator. The first lever arm has a length that is less than a length of the second lever arm. The actuator moves the tool mount along an arc.

  9. A new vibration mechanism of balancing machine for satellite-borne spinning rotors

    Institute of Scientific and Technical Information of China (English)

    Wang Qiuxiao; Wang Fei

    2014-01-01

    The centrifugal force and overturning moment generated by satellite-borne rotating pay-load have a significant impact on the stability of on-orbit satellite attitude, which must be controlled to the qualified range. For the satellite-borne rotors’ low working revs and large centroidal devia-tion and height, and that the horizontal vibration produced by centrifugal force is not of the same magnitude as the torsional vibration by overturning moment, the balancing machine’s measurement accuracy is low. Analysis shows that the mixture of horizontal vibration and torsional vibration of the vibrational mechanism contribute mainly to the machine’s performance, as well as the instabil-ity of vibration center position. A vibrational mechanism was put forward, in which the horizontal and torsional vibration get separated effectively by way of fixing the vibration center. From exper-imental results, the separation between the weak centrifugal force signal and the strong moment sig-nal was realized, errors caused by unstable vibration center are avoided, and the balancing machine based on this vibration structure is able to meet the requirements of dynamic balancing for the satel-lite’s rotating payloads in terms of accuracy and stability.

  10. A new vibration mechanism of balancing machine for satellite-borne spinning rotors

    Directory of Open Access Journals (Sweden)

    Wang Qiuxiao

    2014-10-01

    Full Text Available The centrifugal force and overturning moment generated by satellite-borne rotating payload have a significant impact on the stability of on-orbit satellite attitude, which must be controlled to the qualified range. For the satellite-borne rotors’ low working revs and large centroidal deviation and height, and that the horizontal vibration produced by centrifugal force is not of the same magnitude as the torsional vibration by overturning moment, the balancing machine’s measurement accuracy is low. Analysis shows that the mixture of horizontal vibration and torsional vibration of the vibrational mechanism contribute mainly to the machine’s performance, as well as the instability of vibration center position. A vibrational mechanism was put forward, in which the horizontal and torsional vibration get separated effectively by way of fixing the vibration center. From experimental results, the separation between the weak centrifugal force signal and the strong moment signal was realized, errors caused by unstable vibration center are avoided, and the balancing machine based on this vibration structure is able to meet the requirements of dynamic balancing for the satellite’s rotating payloads in terms of accuracy and stability.

  11. Prediction of Surface Roughness Based on Machining Condition and Tool Condition in Boring EN31 Steel

    Directory of Open Access Journals (Sweden)

    P. Mohanaraman

    2016-04-01

    Full Text Available Prediction of Surface roughness plays a vital role in manufacturing process. In manufacturing industries, productions of metallic materials require high surface finish in various components. In the present work, the effect of spindle speed, feed rate, depth of cut and flank wear of the tool on the surface roughness has been studied. Carbide tipped insert was used for boring operation. Experiments were conducted in CNC lathe. The experimental setup was prepared with sixteen levels of cutting parameters and was conducted with two tool tip conditions in dry machining. A piezoelectric accelerometer was used to measure the vibrational signals while machining. The data acquisition card which connected between accelerometer and lab-view software to record the signals. Simple linear and least median regression models were used for prediction of surface roughness. The models were developed by weka analysis software. The best suitable regression model is implemented based on maximum correlation coefficient and the minimum error values.

  12. Vibration sensing in smart machine rotors using internal MEMS accelerometers

    Science.gov (United States)

    Jiménez, Samuel; Cole, Matthew O. T.; Keogh, Patrick S.

    2016-09-01

    This paper presents a novel topology for enhanced vibration sensing in which wireless MEMS accelerometers embedded within a hollow rotor measure vibration in a synchronously rotating frame of reference. Theoretical relations between rotor-embedded accelerometer signals and the vibration of the rotor in an inertial reference frame are derived. It is thereby shown that functionality as a virtual stator-mounted displacement transducer can be achieved through appropriate signal processing. Experimental tests on a prototype rotor confirm that both magnitude and phase information of synchronous vibration can be measured directly without additional stator-mounted key-phasor sensors. Displacement amplitudes calculated from accelerometer signals will become erroneous at low rotational speeds due to accelerometer zero-g offsets, hence a corrective procedure is introduced. Impact tests are also undertaken to examine the ability of the internal accelerometers to measure transient vibration. A further capability is demonstrated, whereby the accelerometer signals are used to measure rotational speed of the rotor by analysing the signal component due to gravity. The study highlights the extended functionality afforded by internal accelerometers and demonstrates the feasibility of internal sensor topologies, which can provide improved observability of rotor vibration at externally inaccessible rotor locations.

  13. Tool management in manufacturing systems equipped with CNC machines

    Directory of Open Access Journals (Sweden)

    Giovanni Tani

    1997-12-01

    Full Text Available This work has been carried out for the purpose of realizing an automated system for the integrated management of tools within a company. By integrating planning, inspection and tool-room functions, automated tool management can ensure optimum utilization of tools on the selected machines, guaranteeing their effective availability. The first stage of the work consisted of defining and developing a Tool Management System whose central nucleus is a unified Data Base for all of the tools, forming part of the company's Technological Files (files on machines, materials, equipment, methods, etc., interfaceable with all of the company departments that require information on tools. The system assigns code numbers to the individual components of the tools and file them on the basis of their morphological and functional characteristics. The system is also designed to effect assemblies of tools, from which are obtained the "Tool Cards" required for compiling working cycles (CAPP, for CAM programming and for the Tool-room where the tools are physically prepared. Methods for interfacing with suitable systems for the aforesaid functions have also been devised

  14. Adaptive Fuzzy Control System of Servomechanism for Electro-Discharge Machining Combined with Ultrasonic Vibration

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    For electro-discharge machining, only in the optimum state could the highest material removal rate be realized. In practical machining process, the timely elevation of the tool electrode is needed to eliminate chipping, which ordinarily occupies quite a lot of time. Therefore, besides the control of the machining parameters, the control of the optimum discharge gap and the conversion of different machining states is also needed. In this paper, the adaptive fuzzy control system of servomechanism for EDM co...

  15. Research on Positioning Error Compensation for Micro Milling Machine Tool

    Institute of Scientific and Technical Information of China (English)

    Ming-Jun Chen; Wen-Lan Tian; Yong Xiao; Yan Jiang

    2014-01-01

    Micro milling has many advantages in fabricating three⁃dimensional ( 3D) structure in micrometer scale. The micro milling machine tool with high positioning accuracy is of great importance for getting micro structure with high profile precision and good surface quality. Meanwhile, the method of position error compensation is a good way to improve the accuracy of the micro milling machine tools. In this paper, a software method is adopted to compensate the positioning error and improve the positioning accuracy. According to error cancellation theory, the compensation values are generated and compensation tables are built to adjust the positioning error in the NC system based on Industrial Motion and Automation Control ( IMAC) . The positioning accuracy of linear motor is ±0�3μm without backlash after compensation. In order to verify the effectiveness of compensation on the machining performance, concave spherical surfaces are processed on the micro milling machine tool. The experimental results show that the profile radius error of the spherical surface machined with compensation decreases more than 60%.

  16. Dry Machining Tool Design via Chlorine Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    Tatsuhiko Aizawa; Atsushi Mitsuo; Shigeo Yamamoto; Shinji Muraishi; Taro Sumitomo

    2004-01-01

    Dry machining has become a key issue to significantly reduce the wastes of used lubricants and cleaning agents and to improve the environmental consciousness for medical and food applications of special tooling. Since the tools and metallic works are in direct contact in dry, severe adhesive wear and oxidation are thought to occur even at the presence of hard protective coatings. Self-lubrication mechanism with use of lubricous oxide films is found to be effective for dry machining. Through the chlorine ion implantation to tools, titanium base oxides are in-situ formed on the tool surface.This oxide deforms elasto-plastically so that both friction coefficient and wear volume are reduced even in the high-speed cutting.

  17. Dry Machining Tool Design via Chlorine Ion Implantation

    Institute of Scientific and Technical Information of China (English)

    TatsuhikoAizawa; AtsushiMitsuo; ShigeoYamamoto; ShinjiMuraishi; TaroSumitomo

    2004-01-01

    Dry machining has become a key issue to significantly reduce the wastes of used lubricants and cleaning agents and to improve the environmental consciousness for medical and food applications of special tooling. Since the tools and metallic works are in direct contact in dry, severe adhesive wear and oxidation are thought to occur even at the presence of hard protective coatings. Self-lubrication mechanism with use of lubricous oxide films is found to be effective for dry machining. Through the chlorine ion implantation to tools, titanium base oxides are in-situ formed on the tool surface. This oxide deforms elasto-plastically so that both friction coefficient and wear volume are reduced even in the high-speed cutting.

  18. Laboratory directed research and development final report: Intelligent tools for on-machine acceptance of precision machined components

    Energy Technology Data Exchange (ETDEWEB)

    Christensen, N.G.; Harwell, L.D.; Hazelton, A.

    1997-02-01

    On-Machine Acceptance (OMA) is an agile manufacturing concept being developed for machine tools at SNL. The concept behind OMA is the integration of product design, fabrication, and qualification processes by using the machining center as a fabrication and inspection tool. This report documents the final results of a Laboratory Directed Research and Development effort to qualify OMA.

  19. Research on ultrasonic vibration aided femtosecond laser machining process of transparent materials

    Science.gov (United States)

    Dai, Yutang; Liu, Bin; Yin, Guanglin; Li, Tao; Karanja, Joseph M.

    2015-08-01

    A new process of femtosecond laser micromachining with ultrasonic vibration aided is proposed. An ultrasonic aided device has been designed, and the laser micromachining experiments of transparent materials have been carried out. The effects of the ultrasonic vibration with different power on surface quality and the drilling depth have been investigated, and the mechanism of the ultrasonic vibration aided laser machining has been analyzed. After introducing the ultrasonic vibration device, the residue debris on surface of the ablated trench is significantly reduced, and the drilling depth is increased. These results show that, ultrasonic vibration can effectively improve the surface quality of material processing, increase the depth of the drilling hole and promote the processing efficiency of the femtosecond laser.

  20. Design of a novel parallel reconfigurable machine tool

    CSIR Research Space (South Africa)

    Modungwa, D

    2008-06-01

    Full Text Available equipment, with high stiffness. Each worn out mould or die has different defects, which requires different mechanical processing and positioning of the reconditioning tools. Conventional machine tools and serial manipulators have been found incapable... and philosophy of re-configurability. The structure is influenced by 1) specifications for the repair and re- conditioning of moulds and dies, and 2) the manufacturing processes involved. 1. INTRODUCTION Serial manipulators have been used extensively...

  1. Educational Resources for the Machine Tool Industry. Executive Summary.

    Science.gov (United States)

    Texas State Technical Coll. System, Waco.

    This document describes the MASTER (Machine Tool Advanced Skills Educational Resources) program, a geographic partnership of seven of the nation's best 2-year technical and community colleges located in seven states. The project developed and disseminated a national training model for manufacturing processes and new technologies within the…

  2. Critical Technology Assessment of Five Axis Simultaneous Control Machine Tools

    Science.gov (United States)

    2009-07-01

    some of the less traditional end-uses cited in export license applications for these particular machine tools include the manufacture of artificial ... insemination equipment for cattle and the manufacture of moulds for the soles of shoes. C. Military Applications According to DOD’s Military

  3. Optical vibration and deviation measurement of rotating machine parts

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    It is of interest to get appropriate information about the dynamic behaviour of rotating machinery parts in service. This paper presents an approach of optical vibration and deviation measurement of such parts. Essential of this method is an image derotator combined with a high speed camera or a laser doppler vibrometer (LDV).

  4. A Real-Time Tool Positioning Sensor for Machine-Tools

    Science.gov (United States)

    Ruiz, Antonio Ramon Jimenez; Rosas, Jorge Guevara; Granja, Fernando Seco; Honorato, Jose Carlos Prieto; Taboada, Jose Juan Esteve; Serrano, Vicente Mico; Jimenez, Teresa Molina

    2009-01-01

    In machining, natural oscillations, and elastic, gravitational or temperature deformations, are still a problem to guarantee the quality of fabricated parts. In this paper we present an optical measurement system designed to track and localize in 3D a reference retro-reflector close to the machine-tool's drill. The complete system and its components are described in detail. Several tests, some static (including impacts and rotations) and others dynamic (by executing linear and circular trajectories), were performed on two different machine tools. It has been integrated, for the first time, a laser tracking system into the position control loop of a machine-tool. Results indicate that oscillations and deformations close to the tool can be estimated with micrometric resolution and a bandwidth from 0 to more than 100 Hz. Therefore this sensor opens the possibility for on-line compensation of oscillations and deformations. PMID:22408472

  5. A real-time tool positioning sensor for machine-tools.

    Science.gov (United States)

    Ruiz, Antonio Ramon Jimenez; Rosas, Jorge Guevara; Granja, Fernando Seco; Honorato, Jose Carlos Prieto; Taboada, Jose Juan Esteve; Serrano, Vicente Mico; Jimenez, Teresa Molina

    2009-01-01

    In machining, natural oscillations, and elastic, gravitational or temperature deformations, are still a problem to guarantee the quality of fabricated parts. In this paper we present an optical measurement system designed to track and localize in 3D a reference retro-reflector close to the machine-tool's drill. The complete system and its components are described in detail. Several tests, some static (including impacts and rotations) and others dynamic (by executing linear and circular trajectories), were performed on two different machine tools. It has been integrated, for the first time, a laser tracking system into the position control loop of a machine-tool. Results indicate that oscillations and deformations close to the tool can be estimated with micrometric resolution and a bandwidth from 0 to more than 100 Hz. Therefore this sensor opens the possibility for on-line compensation of oscillations and deformations.

  6. The Qualitative Research Method of Dynamics Vibration of a Washing Machine Based on Riccati Equation

    Directory of Open Access Journals (Sweden)

    Sergey P. Petrosov

    2012-09-01

    Full Text Available The accurate method for finding the common solutions of weakly interconnected system of nonhomogeneous differential equations with variable coefficients based on Riccati Equation was developed. This method describes the dynamics of vibration of the suspension drum type of a washing machine in spin mode.

  7. Evaluation of rotor axial vibrations in a turbo pump unit equipped with an automatic unloading machine

    Science.gov (United States)

    Martsynkovskyy, V. A.; Deineka, A.; Kovalenko, V.

    2017-08-01

    The article presents forced axial vibrations of the rotor with an automatic unloading machine in an oxidizer pump. A feature of the design is the use in the autoloading system of slotted throttles with mutually inverse throttling. Their conductivity is determined by a numerical experiment in the ANSYS CFX software package.

  8. Study on the nano machining process with a vibrating AFM tip on the polymer surface

    Energy Technology Data Exchange (ETDEWEB)

    Liu Weitao [State Key Laboratory of Robotics and Systems, Robotics Institute, Harbin Institute of Technology, Harbin 150080 (China); Center for Precision Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001 (China); Yan Yongda, E-mail: yanyongda@yahoo.com.cn [State Key Laboratory of Robotics and Systems, Robotics Institute, Harbin Institute of Technology, Harbin 150080 (China); Center for Precision Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001 (China); Hu Zhenjiang; Zhao Xuesen; Yan Jiucun; Dong Shen [Center for Precision Engineering, Harbin Institute of Technology, Harbin, Heilongjiang 150001 (China)

    2012-01-15

    The polymer has been proved to be nano machined by a vibrating tip in tapping mode of Atomic Force Microscope (AFM). The force between the tip and the surface is an important factor which determines success of the machining process. Controlling this force with high accuracy is the foundation of nanomachining in AFM tapping mode. To achieve a deeper understanding on this process, the tip is modeled as a driving oscillator with damping. Factors affecting the nano machining process are studied. The Hertz elastic contact theory is used to calculate the maximum contact pressure applied by the tip which is employed as a criterion to judge the deformation state of the sample. The simulation results show that: The driven amplitude can be used as a main parameter of controlling the machined depth. Sharper tips and harder cantilevers should be used for successful nanomachining with the vibrating tip. Under the same conditions, a larger tip radius will not only result in the machining error, but also lead to failure of the nanomachining process. The higher driving frequency will lead to a larger tapping force. However it cannot be used as a parameter to control the machined depth because of its narrow variation range. But it is a main error source for the nanomachining process in AFM tapping mode. Moreover, a larger Young's modulus polymer sample will induce a smaller machined depth, a larger maximum contact pressure and a bigger tapping force.

  9. Application of TRIZ approach to machine vibration condition monitoring problems

    Science.gov (United States)

    Cempel, Czesław

    2013-12-01

    Up to now machine condition monitoring has not been seriously approached by TRIZ1TRIZ= Russian acronym for Inventive Problem Solving System, created by G. Altshuller ca 50 years ago. users, and the knowledge of TRIZ methodology has not been applied there intensively. However, there are some introductory papers of present author posted on Diagnostic Congress in Cracow (Cempel, in press [11]), and Diagnostyka Journal as well. But it seems to be further need to make such approach from different sides in order to see, if some new knowledge and technology will emerge. In doing this we need at first to define the ideal final result (IFR) of our innovation problem. As a next we need a set of parameters to describe the problems of system condition monitoring (CM) in terms of TRIZ language and set of inventive principles possible to apply, on the way to IFR. This means we should present the machine CM problem by means of contradiction and contradiction matrix. When specifying the problem parameters and inventive principles, one should use analogy and metaphorical thinking, which by definition is not exact but fuzzy, and leads sometimes to unexpected results and outcomes. The paper undertakes this important problem again and brings some new insight into system and machine CM problems. This may mean for example the minimal dimensionality of TRIZ engineering parameter set for the description of machine CM problems, and the set of most useful inventive principles applied to given engineering parameter and contradictions of TRIZ.

  10. Laser-error-correction control unit for machine tools

    Energy Technology Data Exchange (ETDEWEB)

    Burleson, R.R.

    1978-05-23

    An ultraprecision machining capability is needed for the laser fusion program. For this work, a precision air-bearing spindle has been mounted horizontally on a modified vertical column of a Moore Number 3 measuring machine base located in a development laboratory at the Oak Ridge Y-12 Plant. An open-loop control system previously installed on this machine was inadequate to meet the upcoming requirements since accuracy is limited to 0.5 ..mu..m by the errors in the machine's gears and leadscrew. A new controller was needed that could monitor the actual position of the machine and perform real-time error correction on the programmed tool path. It was necessary that this project: (1) attain an optimum tradeoff between hardware and software; (2) use a modular design for easy maintenance; (3) use a standard NC tape service; (4) drive the x and y axes with a positioning resolution of 5.08 nm and a feedback resolution of 10 nm; (5) drive the x and y axis motors at a velocity of 0.05 cm/sec in the contouring mode and 0.18 cm/sec in the positioning mode; (6) eliminate the possibility of tape-reader errors; and (7) allow editing of the part description data. The work that was done to develop and install the new machine controller is described.

  11. Innovative Control of Noise and Vibration of Industrial Equipments and Machines

    Directory of Open Access Journals (Sweden)

    Owhor, Sampson Chisa,

    2015-05-01

    Full Text Available Noise and Vibration of industrial equipment is the grave factor influencing its production state, working conditions of staff and job safety. In course of technology development the more potent machines are used, it is quite often accompanied by an increase of vibration and noise level. This is experienced by equipment as it is transmitted to building structures, environment and through staffs. The system of equation advocated in this research work has been permitted to evaluate reduction of machine vibrations caused by unbalance movement of its members, thereby transmitting it onto the floor and the environment. A noise problem generally consists of three inter-related elements- the source, the receiver and the transmission path. This transmission path is usually the atmosphere through which the sound is propagated, but can include structural materials of any building containing the receiver. The development of innovative noise control treatments provides opportunities for applying basic physics and engineering procedures.

  12. VIBRATION SENSOR FOR HEALTH MONITORING OF ELECTRICAL MACHINES IN POWER STATION

    Directory of Open Access Journals (Sweden)

    Neha Gupta

    2012-04-01

    Full Text Available Vibration monitoring in high power electric machines, such as generators and transformers, presents some difficulties due to the insulation and EM immunity requirements .However, the negative influence of the electromagnetic interference (EMI can be a real problem when electrical signals are used to detect and transmitphysical parameters in noisy environments such as electric power generator plants with high levels of EMI. Such problems can be solved using optical fiber sensors, which allow in situ measurements and remote control without electrical wires. The present paper describes a novel fiber optic vibration sensor for health monitoring of electrical machines, which utilizes relatively simple technologies and offers moderate costs. The sensor is optimized for detection of mechanical vibrations in the frequency range 20-100 Hz. Design details and experimental results are reported.

  13. Smart adaptronic hydrostatic guiding system for machine tool slides

    Science.gov (United States)

    Munzinger, C.; Weis, M.; Herder, S.

    2009-03-01

    Guiding systems figure amongst the central components in the flux of a machine tool. Their characteristics have a direct impact on machining accuracy. Hydrostatic guiding systems are preferably used when specific requirements are to be met with regards to accuracy, stiffness and damping. However, an active intervention in the guiding system of such conventional systems, i.e. to absorb geometrical guiding rail errors, has so far not been possible. Compared to modular, conventional systems, adaptronic systems offer considerable cost savings potentials thanks to their increased functional degree of integration [1].

  14. Influence of machining parameters on cutting tool life while machining aluminum alloy fly ash composite

    Science.gov (United States)

    Rao, C. R. Prakash; chandra, Poorna; Kiran, R.; Asha, P. B.

    2016-09-01

    Metal matrix composites containing fly ash as reinforcement are primarily preferred because these materials possess lower density and higher strength to weight ratio. The metal matrix composites possess hetrogeneous microstructure which is due to the presence of hard ceramic particles. While turning composites, the catastrophic failure of cutting tools is attributed to the presence of hard particles. Selection of optimal cutting conditions for a given machining process and grade of cutting tools are of utmost importance to enhance the tool life during turning operation. Thus the research work was aimed at the experimental investigation of the cutting tool life while machining aluminum alloy composite containing 0-15% fly-ash. The experiments carried out following ISO3685 standards. The carbide inserts of grade K10 and style CGGN120304 were the turning tools. The cutting speed selected was between 200m/min to 500m/min in step of 100m/min, feed of 0.08 & 0.16 mm/revolution and constant depth of cut of 1.0 mm. The experimental results revealed that the performance of K10 grade carbide insert found better while machining composite containing 5% filler, at all cutting speeds and 0.08mm/revolution feed. The failures of carbide tools are mainly due to notch wear followed by built up edge and edge chipping.

  15. A Real-Time Tool Positioning Sensor for Machine-Tools

    Directory of Open Access Journals (Sweden)

    Vicente Mico Serrano

    2009-09-01

    Full Text Available In machining, natural oscillations, and elastic, gravitational or temperature deformations, are still a problem to guarantee the quality of fabricated parts. In this paper we present an optical measurement system designed to track and localize in 3D a reference retro-reflector close to the machine-tool’s drill. The complete system and its components are described in detail. Several tests, some static (including impacts and rotations and others dynamic (by executing linear and circular trajectories, were performed on two different machine tools. It has been integrated, for the first time, a laser tracking system into the position control loop of a machine-tool. Results indicate that oscillations and deformations close to the tool can be estimated with micrometric resolution and a bandwidth from 0 to more than 100 Hz. Therefore this sensor opens the possibility for on-line compensation of oscillations and deformations.

  16. The effect of geometric structure on stiffness and damping factor of wood applicable to machine tool structure

    Directory of Open Access Journals (Sweden)

    Susilo Adi Widyanto

    2013-06-01

    Full Text Available Stiffness and vibration damping capability are important criteria in design of machine tool structure. In other sides, the weight of machine tool structure must be reduced to increase  the handling capability. This paper presents  an analysis of the effect of geometric structure on stiffness and vibration damping of wood structure.  The stiffness was analysed  using numerical method, so called finite element method (FEM, while the vibration damping capability was experimentally tested. Vibration testing was also performed to wood structures with sand powder filled  into  its rectangular hole to observe the its effect on damping factor. Simulation results show  that the cross ribs structure yielded minimum mass reduction ratio compared to the three square holes as well as the single rectangular hole structures. While the vibration test results explained that the damping factor of Shorea laevis wood was higher than that Hevea braziiensis wood. The use of sand powder as vibrating  mass in closed-box structure effectively increased the damping capability, for single rectangular hole structure the damping factor was increased from 0.048 to 0.079doi: http://dx.doi.org/10.12777/ijse.4.2.2013.57-60[How to cite the article: Widyanto, S. A., Widodo, A., Nugroho, S., & Siahaan, D. (2013. The effect of geometric structure on stiffness and damping factor of wood applicable to machine tool structure. INTERNATIONAL JOURNAL OF SCIENCE AND ENGINEERING, 4(2, 57-60. doi: http://dx.doi.org/10.12777/ijse.4.2.2013.57-60

  17. Virtual Sensor for Calibration of Thermal Models of Machine Tools

    Directory of Open Access Journals (Sweden)

    Alexander Dementjev

    2014-01-01

    strictly depends on the accuracy of these machines, but they are prone to deformation caused by their own heat. The deformation needs to be compensated in order to assure accurate production. So an adequate model of the high-dimensional thermal deformation process must be created and parameters of this model must be evaluated. Unfortunately, such parameters are often unknown and cannot be calculated a priori. Parameter identification during real experiments is not an option for these models because of its high engineering and machine time effort. The installation of additional sensors to measure these parameters directly is uneconomical. Instead, an effective calibration of thermal models can be reached by combining real and virtual measurements on a machine tool during its real operation, without additional sensors installation. In this paper, a new approach for thermal model calibration is presented. The expected results are very promising and can be recommended as an effective solution for this class of problems.

  18. Machine Learning: A Crucial Tool for Sensor Design

    Directory of Open Access Journals (Sweden)

    Weixiang Zhao

    2008-12-01

    Full Text Available Sensors have been widely used for disease diagnosis, environmental quality monitoring, food quality control, industrial process analysis and control, and other related fields. As a key tool for sensor data analysis, machine learning is becoming a core part of novel sensor design. Dividing a complete machine learning process into three steps: data pre-treatment, feature extraction and dimension reduction, and system modeling, this paper provides a review of the methods that are widely used for each step. For each method, the principles and the key issues that affect modeling results are discussed. After reviewing the potential problems in machine learning processes, this paper gives a summary of current algorithms in this field and provides some feasible directions for future studies.

  19. Optimal Machine Tools Selection Using Interval-Valued Data FCM Clustering Algorithm

    Directory of Open Access Journals (Sweden)

    Yupeng Xin

    2014-01-01

    Full Text Available Machine tool selection directly affects production rates, accuracy, and flexibility. In order to quickly and accurately select the appropriate machine tools in machining process planning, this paper proposes an optimal machine tools selection method based on interval-valued data fuzzy C-means (FCM clustering algorithm. We define the machining capability meta (MAE as the smallest unit to describe machining capacity of machine tools and establish MAE library based on the MAE information model. According to the manufacturing process requirements, the MAEs can be queried from MAE library. Subsequently, interval-valued data FCM algorithm is used to select the appropriate machine tools for manufacturing process. Through computing matching degree between manufacturing process machining constraints and MAEs, we get the most appropriate MAEs and the corresponding machine tools. Finally, a case study of an exhaust duct part of the aeroengine is presented to demonstrate the applicability of the proposed method.

  20. ANN Based Tool Condition Monitoring System for CNC Milling Machines

    Directory of Open Access Journals (Sweden)

    Mota-Valtierra G.C.

    2011-10-01

    Full Text Available Most of the companies have as objective to manufacture high-quality products, then by optimizing costs, reducing and controlling the variations in its production processes it is possible. Within manufacturing industries a very important issue is the tool condition monitoring, since the tool state will determine the quality of products. Besides, a good monitoring system will protect the machinery from severe damages. For determining the state of the cutting tools in a milling machine, there is a great variety of models in the industrial market, however these systems are not available to all companies because of their high costs and the requirements of modifying the machining tool in order to attach the system sensors. This paper presents an intelligent classification system which determines the status of cutt ers in a Computer Numerical Control (CNC milling machine. This tool state is mainly detected through the analysis of the cutting forces drawn from the spindle motors currents. This monitoring system does not need sensors so it is no necessary to modify the machine. The correct classification is made by advanced digital signal processing techniques. Just after acquiring a signal, a FIR digital filter is applied to the data to eliminate the undesired noisy components and to extract the embedded force components. A Wavelet Transformation is applied to the filtered signal in order to compress the data amount and to optimize the classifier structure. Then a multilayer perceptron- type neural network is responsible for carrying out the classification of the signal. Achieving a reliability of 95%, the system is capable of detecting breakage and a worn cutter.

  1. MACHINING OF NICKEL BASED ALLOYS USING DIFFERENT CEMENTED CARBIDE TOOLS

    Directory of Open Access Journals (Sweden)

    BASIM A. KHIDHIR

    2010-09-01

    Full Text Available This paper presents the results of experimental work in dry turning of nickel based alloys (Haynes – 276 using Deferent tool geometer of cemented carbide tools. The turning tests were conducted at three different cutting speeds (112, 152, 201and 269 m/min while feed rate and depth of cut were kept constant at 0.2 mm/rev and 1.5 mm, respectively. The tool holders used were SCLCR with insert CCMT-12 and CCLNR – M12-4 with insert CNGN-12. The influence of cutting speed, tool inserts type and workpiece material was investigated on the machined surface roughness. The worn parts of the cutting tools were also examined under scanning electron microscope (SEM. The results showed that cutting speed significantly affected the machined surface finish values in related with the tool insert geometry. Insert type CCMT-12 showed better surface finish for cutting speed to 201 m/min, while insert type CNGN-12 surface roughness increased dramatically with increasing of speed to a limit completely damage of insert geometer beyond 152 m/min.

  2. Series Design of Large-Scale NC Machine Tool

    Institute of Scientific and Technical Information of China (English)

    TANG Zhi

    2007-01-01

    Product system design is a mature concept in western developed countries. It has been applied in war industry during the last century. However, up until now, functional combination is still the main method for product system design in China. Therefore, in terms of a concept of product generation and product interaction we are in a weak position compared with the requirements of global markets. Today, the idea of serial product design has attracted much attention in the design field and the definition of product generation as well as its parameters has already become the standard in serial product designs. Although the design of a large-scale NC machine tool is complicated, it can be further optimized by the precise exercise of object design by placing the concept of platform establishment firmly into serial product design. The essence of a serial product design has been demonstrated by the design process of a large-scale NC machine tool.

  3. INVERSE DYNAMIC FORMULATION OF A NOVEL HYBRID MACHINE TOOL

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In recent years, hybrid devices have increasingly received more research.However, few of researchers studied the dynamic analysis.The inverse dynamic analysis of a novel hybrid machine tool designed in Tsinghua University is presented.The hybrid machine tool under consideration consists of parallel and serial structures, which is based on a new 2-DOF parallel platform and serial orientations.The kinematics and the dynamic equations are studied first for the parallel structure through Newton-Euler approach.And then, the dynamic analysis for serial structures is conducted.Finally, a closed-form inverse dynamic formulation is derived by using some elimination techniques.Some simulation results are also given.

  4. A general thermal model of machine tool spindle

    Directory of Open Access Journals (Sweden)

    Yanfang Dong

    2017-01-01

    Full Text Available As the core component of machine tool, the thermal characteristics of the spindle have a significant influence on machine tool running status. Lack of an accurate model of the spindle system, particularly the model of load–deformation coefficient between the bearing rolling elements and rings, severely limits the thermal error analytic precision of the spindle. In this article, bearing internal loads, especially the function relationships between the principal curvature difference F(ρ and auxiliary parameter nδ, semi-major axis a, and semi-minor axis b, have been determined; furthermore, high-precision heat generation combining the heat sinks in the spindle system is calculated; finally, an accurate thermal model of the spindle was established. Moreover, a conventional spindle with embedded fiber Bragg grating temperature sensors has been developed. By comparing the experiment results with simulation, it indicates that the model has good accuracy, which verifies the reliability of the modeling process.

  5. Configuration Design of Product Service System for CNC Machine Tools

    OpenAIRE

    Zhongqi Sheng; Tao Xu; Junyou Song

    2015-01-01

    Product service system is a combination of product and services to meet the customer requirements. Configuration design is the key process of product service system development. This paper studies the configuration design of product service system for CNC machine tools. The research explores the configuration design process of product service system development, analyzes the retrieval method of product service system schemes, determines the configuration sequence of product modules and servic...

  6. Editing of EIA coded, numerically controlled, machine tool tapes

    Science.gov (United States)

    Weiner, J. M.

    1975-01-01

    Editing of numerically controlled (N/C) machine tool tapes (8-level paper tape) using an interactive graphic display processor is described. A rapid technique required for correcting production errors in N/C tapes was developed using the interactive text editor on the IMLAC PDS-ID graphic display system and two special programs resident on disk. The correction technique and special programs for processing N/C tapes coded to EIA specifications are discussed.

  7. Kinematic Analysis of a Serial - Parallel Machine Tool: the VERNE machine

    CERN Document Server

    Kanaan, Daniel; Chablat, Damien; 10.1016/j.mechmachtheory.2008.03.002

    2008-01-01

    The paper derives the inverse and the forward kinematic equations of a serial - parallel 5-axis machine tool: the VERNE machine. This machine is composed of a three-degree-of-freedom (DOF) parallel module and a two-DOF serial tilting table. The parallel module consists of a moving platform that is connected to a fixed base by three non-identical legs. These legs are connected in a way that the combined effects of the three legs lead to an over-constrained mechanism with complex motion. This motion is defined as a simultaneous combination of rotation and translation. In this paper we propose symbolical methods that able to calculate all kinematic solutions and identify the acceptable one by adding analytical constraint on the disposition of legs of the parallel module.

  8. Research advances in coupling bionic optimization design method for CNC machine tools based on ergonomics

    Directory of Open Access Journals (Sweden)

    Shihao LIU

    2015-06-01

    Full Text Available Currently, most Chinese CNC machine tools' dynamic and static performances have large gap comparing with the similar foreign products, and the CNC machine tools users' human-centered design demand are ignored, which results in that the domestic CNC machine tools' overall competitiveness is relatively low. In order to solve the above problem, the ergonomics and coupling bionics are adopted to study collaborative optimization design method for CNC machine tools based on the domestic and foreign machine tool design method research achievement. The CNC machine tools' "man-machine-environment" interaction mechanism can be built by combining with ergonomic, and then the CNC ergonomic design criteria is obtained. Taking the coupling bionics as theoretical basis, the biological structures "morphology-structure-function-adaptive growth" multiple coupling mechanism can be studied, and the mechanical performance benefits structure can be extracted, then the CNC machine tools structural coupling bionic design technology is obtained by combining with the similarity principle. Combination of CNC machine tools' ergonomic design criteria and coupling bionic design technology, and considering the CNC machine tool performance's interaction and coupling mechanisms, a new multi-objective optimization design method can be obtained, which is verified through CNC machine tools' prototype experiments. The new optimization design method for CNC machine tools can not only help improve the whole machine's dynamic and static performance, but also has a bright prospect because of the "man-oriented" design concept.

  9. Condition monitoring of PARR-1 rotating machines by vibration analysis technique

    Directory of Open Access Journals (Sweden)

    Qadir Javed

    2014-01-01

    Full Text Available Vibration analysis is a key tool for preventive maintenance involving the trending and analysis of machinery performance parameters to detect and identify developing problems before failure and extensive damage can occur. A lab-based experimental setup has been established for obtaining fault-free and fault condition data. After this analysis, primary and secondary motor and pump vibration data of the Pakistan Research Reactor-1 were obtained and analyzed. Vibration signatures were acquired in horizontal, vertical, and axial directions. The 48 vibration signatures have been analyzed to assess the operational status of motors and pumps. The vibration spectrum has been recorded for a 2000 Hz frequency span with a 3200 lines resolution. The data collected should be helpful in future Pakistan Research Reactor-1 condition monitoring.

  10. Control of seismic and operational vibrations of rotating machines using semi-active mounts

    Institute of Scientific and Technical Information of China (English)

    R.Rana; T.T.Soong

    2004-01-01

    A dual isolation problem for rotating machines consists of isolation of housing structures from the machine vibrations and protection of machines during an earthquake to maintain their functionality. Desirable characteristics of machine mounts for the above two purposes can differ significantly due to difference in nature of the excitation and performance criteria in the two situations. In this paper, relevant response quantities are identified that may be used to quantify performancc and simplified models of rotating machines are presented using which these relevant response quantities may be calculated. Using random vibration approach with a stationary excitation, it is shown that significant improvement in seismic performance is achievable by proper mount design. Results of shaking table experiments performed with a realistic setup using a centrifugal pump are presented. It is concluded that a solution to this dual isolation problem lies in a semi-active.mount capable of switching its properties from‘operation-optimum'to‘seismic-optimum'at the omset of a seismic event.

  11. 76 FR 27668 - ASC Machine Tools, Inc., Spokane Valley, WA; Notice of Negative Determination on Reconsideration

    Science.gov (United States)

    2011-05-12

    ... Employment and Training Administration ASC Machine Tools, Inc., Spokane Valley, WA; Notice of Negative... Regarding Application for Reconsideration for the workers and former workers of ASC Machine Tools, Inc... adjustment assistance for workers and former workers of ASC Machine Tools, Inc., Spokane Valley,...

  12. Application of new tool material for electrical discharge machining (EDM)

    Indian Academy of Sciences (India)

    A K Khanra; L C Pathak; M M Godkhindi

    2009-08-01

    In EDM, Cu and graphite are commonly used as tool materials. The poor wear resistance is the drawback of these tools. In the current study, an attempt has been made to develop a ZrB2–Cu composite as an EDM tool material to overcome this problem. Initially, the ZrB2 powder is prepared by self-propagating high-temperature synthesis (SHS) technique and synthesized powder is mixed with different amounts of Cu powder. Dense composite is developed by a pressureless sintering at 1250°C. The composites are tested as tool material at different EDM process parameters during machining of mild steel. The ZrB2–40 wt% Cu composite shows highest metal removal rate (MRR) with significant tool removal rate (TRR) than other composites. The performance of ZrB2–40 wt% Cu composite is compared to conventional Cu tool. The composite shows higher MRR with less TRR than Cu tool but it shows more average surface roughness and diameteral overcut than Cu tool.

  13. Design and verification of a novel hollow vibrating module for laser machining.

    Science.gov (United States)

    Wang, Zhaozhao; Jang, Seungbong; Kim, EunHee; Jeon, Yongho; Lee, Soo-Hun; Lee, Moon G

    2015-04-01

    If a vibration module is added on laser machining system, the quality of surface finish and aspect ratio on metals can be significantly enhanced. In this study, a single mobility model of vibrating laser along the path of laser beam was put forward. In order to realize the desired unidirectional motion, a resonance type vibration module with optical lens was designed and manufactured. This cylindrical module was composed of curved-beam flexure elements. The cylindrical coordinate system was established to describe the relationship of a curved-beam flexure element's motion and deformation. In addition, the stiffness matrix of the curved-beam element was obtained. Finite element method and dynamical modeling were provided to analyze the resonance frequency and the displacement of the motion. The feasibility of the design was demonstrated with the help of experiments on frequency response. Experimental results show good agreement with theoretical analysis and simulation predictions.

  14. Alternative Vibration Protecting Systems for Men-Operators of Transport Machines: Modern Level and Prospects

    Science.gov (United States)

    LEE, C.-M.; GOVERDOVSKIY, V. N.

    2002-01-01

    The up-to-date level and a few of the prospects are considered in transport biomechanical vibration protection systems. An experimental estimation of the maximum capabilities of traditional vibration protecting mechanisms (VPMs) used in driver seats is given. Some of the points of synthesis and research for the adaptive VPMs, called mechanisms of elastic links with small stiffness (ELSS-mechanisms) are presented. They contain a novel object of control: non-linear elastic elements with variable torsion “negative” stiffness (TNS). These TNS-elements help to optimize VPMs according to certain criteria and give them invariant structural and functional properties. Some experimental results are presented, and they correspond well with theoretical predictions. An approach is demonstrated for grade of quality of vibration protection of the men-operators of land unsuspended machines and pilots of helicopters.

  15. GA-Based Autonomous Design of Robust Fast and Precise Positioning Considering Machine Stand Vibration Suppression

    Science.gov (United States)

    Ito, Kazuaki; Nagata, Ryo; Iwasaki, Makoto; Matsui, Nobuyuki

    This paper presents a novel Genetic Algorithm (GA)-based autonomous compensator design and position command shaping considering the stand vibration suppression for the fast-response and high-precision positioning of mechatronic systems. The positioning system is mainly composed of a robust 2-degrees-of-freedom (2DOF) controller based on the coprime factorization description. The feedback compensator based on H∞ design framework in the 2DOF controller ensures the robustness against the variations of resonant vibration mode. The feedforward compensator and position command, on the other hand, can be autonomously designed by the optimization capability of GA, in order to achieve the desired positioning performance and to suppress the machine stand vibration. The effectiveness of the proposed optimal design has been verified by experiments using a table drive system with ball screw.

  16. Condition monitoring of face milling tool using K-star algorithm and histogram features of vibration signal

    Directory of Open Access Journals (Sweden)

    C.K. Madhusudana

    2016-09-01

    Full Text Available This paper deals with the fault diagnosis of the face milling tool based on machine learning approach using histogram features and K-star algorithm technique. Vibration signals of the milling tool under healthy and different fault conditions are acquired during machining of steel alloy 42CrMo4. Histogram features are extracted from the acquired signals. The decision tree is used to select the salient features out of all the extracted features and these selected features are used as an input to the classifier. K-star algorithm is used as a classifier and the output of the model is utilised to study and classify the different conditions of the face milling tool. Based on the experimental results, K-star algorithm is provided a better classification accuracy in the range from 94% to 96% with histogram features and is acceptable for fault diagnosis.

  17. On Electro Discharge Machining of Inconel 718 with Hollow Tool

    Science.gov (United States)

    Rajesha, S.; Sharma, A. K.; Kumar, Pradeep

    2012-06-01

    Inconel 718 is a nickel-based alloy designed for high yield, tensile, and creep-rupture properties. This alloy has been widely used in jet engines and high-speed airframe parts in aeronautic application. In this study, electric discharge machining (EDM) process was used for machining commercially available Inconel 718. A copper electrode with 99.9% purity having tubular cross section was employed to machine holes of 20 mm height and 12 mm diameter on Inconel 718 workpieces. Experiments were planned using response surface methodology (RSM). Effects of five major process parameters—pulse current, duty factor, sensitivity control, gap control, and flushing pressure on the process responses—material removal rate (MRR) and surface roughness (SR) have been discussed. Mathematical models for MRR and SR have been developed using analysis of variance. Influences of process parameters on tool wear and tool geometry have been presented with the help of scanning electron microscope (SEM) micrographs. Analysis shows significant interaction effect of pulse current and duty factor on MRR yielding a wide range from 14.4 to 22.6 mm3/min, while pulse current remains the most contributing factor with approximate changes in the MRR and SR of 48 and 37%, respectively, corresponding to the extreme values considered. Interactions of duty factor and flushing pressure yield a minimum surface roughness of 6.2 μm. The thickness of the sputtered layer and the crack length were found to be functions of pulse current. The hollow tool gets worn out on both the outer and the inner edges owing to spark erosion as well as abrasion due to flow of debris.

  18. Finishing aeronautical planetary herringbone gear wheels in container vibrating smoothing machine

    Directory of Open Access Journals (Sweden)

    Jacek MICHALSKI

    2015-12-01

    Full Text Available The paper presents the technological process of abrasive-chemical machining wheel bearing surface of the cylindrical herringbone gears planetary gear in vibrating container smoothing machine according to Isotropic Finishing ISF® technology of the REM Chemicals Inc. company. Gear wheels are made of stainless Pyrowear 53 and subjected to carburizing, hardening, cold working and low tempering. The change in value of deviation indicators for the kinematic accuracy, smoothness and geometric structure of the machined surfaces of the gear teeth after smoothing compared with the contoured grinding were analyzed. The findings are different a characteristic performance on the surface of the tooth side along the outline, especially with a higher value at the head of the tooths. This creates a need for appropriate modification of the lateral surface of the teeth in the process of contoured grinding. The results of the mechanical strength of the samples gear wheel after the smoothing process and evaluating the hydrogen embrittlement are presented.

  19. Simulation Process Analysis of Rubber Shock Absorber for Machine Tool

    Directory of Open Access Journals (Sweden)

    Chai Rong Xia

    2016-01-01

    Full Text Available The simulation on rubber shock absorber of machine tool was studied. The simple material model of rubber was obtained by through the finite element analysis software ABAQUS. The compression speed and the hardness of rubber material were considered to obtain the deformation law of rubber shock absorber. The location of fatigue were confirmed from the simulation results. The results shown that the fatigue position is distributed in the corner of shock absorber. The degree of deformation is increased with increasing of compress speed, and the hardness of rubber material is proportional to deformation.

  20. Error Model and Accuracy Calibration of 5-Axis Machine Tool

    Directory of Open Access Journals (Sweden)

    Fangyu Pan

    2013-08-01

    Full Text Available To improve the machining precision and reduce the geometric errors for 5-axis machinetool, error model and calibration are presented in this paper. Error model is realized by the theory of multi-body system and characteristic matrixes, which can establish the relationship between the cutting tool and the workpiece in theory. The accuracy calibration was difficult to achieve, but by a laser approach-laser interferometer and laser tracker, the errors can be displayed accurately which is benefit for later compensation.

  1. Reducing maintenance costs in agreement with CNC machine tools reliability

    Science.gov (United States)

    Ungureanu, A. L.; Stan, G.; Butunoi, P. A.

    2016-08-01

    Aligning maintenance strategy with reliability is a challenge due to the need to find an optimal balance between them. Because the various methods described in the relevant literature involve laborious calculations or use of software that can be costly, this paper proposes a method that is easier to implement on CNC machine tools. The new method, called the Consequence of Failure Analysis (CFA) is based on technical and economic optimization, aimed at obtaining a level of required performance with minimum investment and maintenance costs.

  2. Dimensional Synthesis Design of Novel Parallel Machine Tool

    Institute of Scientific and Technical Information of China (English)

    汪劲松; 唐晓强; 段广洪; 尹文生

    2002-01-01

    This paper presents dimensional synthesis design theory for a novel planar 3-DOF (degrees of freedom) parallel machine tool. Closed-form solutions are developed for both the inverse and direct kinematics. The formulation of the dexterity and the definitions of the theoretical workspace and the valid workspace are used to analyze the effects of the design parameters on the dexterity and workspace. The analysis results are used to propose an approach to satisfy the platform motion requirement while realizing orientation capability, dexterity and valid workspace. A design example is given to illustrate the effectiveness of this approach.

  3. A review of designing machine tool for leanness

    Indian Academy of Sciences (India)

    Anil Gupta; T K Kundra

    2012-04-01

    As an ideology, Leanness is not a new concept but still researchers strive for developing new methods to reduce almost all kinds of identified wastages at almost every stage and in every activity — right from design till delivery of final product to the end-customer. Newly developed manufacturing ideologies, paradigms and systems are always critically examined from the point of view of leanness. In other words, leanness is becoming an important evaluation tool to compare the recently developed/pioneered approaches. There has been a gradual evolution of the leanness over the years from the shop floor level of a manufacturing (automobile) organization to almost every operational and management aspect now. The Leanness has undergone and still is undergoing a process of continuous and never-ending evolution due to its inherently built dynamic concept of continuous improvement. Although in the literature a lot of work has been reported to the application of lean tools, principles, theories and methodologies to production systems, but a very few is evident in the area of Lean design process of a product and machine tool. For this reason an attempt is being made here to focus a significant proportion of this paper on evolutionary aspect of leanness from manufacturing to design stage. Also, this paper reviews the concepts and practices being followed till date by the industrialists, researchers and academicians in applying lean tools and techniques in the design of product and machine tools along with the methods to measure the lean improvements in the systems.

  4. THE CONFORMITY OF MACHINE TOOLS WITH RESPECT TO EUROPEAN SAFETY STANDARDS

    CERN Multimedia

    TIS/TE

    2001-01-01

    European regulations require that all motorized machine tools conform to the latest safety standards by the end of the year 2000. CERN must follow these regulations and has already modified most of its machine tools accordingly. However, there is still a small number of machine tools which have not yet been modified as required. These machines should not be used until they are brought up to the required safety standards, failing which the machines should be discarded. One can recognise which machine tools conform with the latest standards by the indication 'CS' on the identification plate of the machine, see foto below. In cases of doubt about the status of a machine tool you should contact K. Altherr/EST or C. Margaroli/TIS for advice.

  5. THE CONFORMITY OF MACHINE TOOLS WITH RESPECT TO EUROPEAN SAFETY STANDARDS

    CERN Multimedia

    TIS/TE

    2000-01-01

    European regulations require that all motorized machine tools conform to the latest safety standards by the end of the year 2000. CERN must follow these regulations and has already modified most of its machine tools accordingly. However, there is still a small number of machine tools which have not yet been modified as required. These machines should not be used until they are brought up to the required safety standards, failing which the machines should be discarded. One can recognise which machine tools conform with the latest standards by the indication 'CS' on the identification plate of the machine, see foto below. In cases of doubt about the status of a machine tool you should contact K. Altherr/EST or C. Margaroli/TIS for advice.

  6. Modelling and simulation of effect of ultrasonic vibrations on machining of Ti6Al4V.

    Science.gov (United States)

    Patil, Sandip; Joshi, Shashikant; Tewari, Asim; Joshi, Suhas S

    2014-02-01

    The titanium alloys cause high machining heat generation and consequent rapid wear of cutting tool edges during machining. The ultrasonic assisted turning (UAT) has been found to be very effective in machining of various materials; especially in the machining of "difficult-to-cut" material like Ti6Al4V. The present work is a comprehensive study involving 2D FE transient simulation of UAT in DEFORM framework and their experimental characterization. The simulation shows that UAT reduces the stress level on cutting tool during machining as compared to that of in continuous turning (CT) barring the penetration stage, wherein both tools are subjected to identical stress levels. There is a 40-45% reduction in cutting forces and about 48% reduction in cutting temperature in UAT over that of in CT. However, the reduction magnitude reduces with an increase in the cutting speed. The experimental analysis of UAT process shows that the surface roughness in UAT is lower than in CT, and the UATed surfaces have matte finish as against the glossy finish on the CTed surfaces. Microstructural observations of the chips and machined surfaces in both processes reveal that the intensity of thermal softening and shear band formation is reduced in UAT over that of in CT.

  7. Enhanced Vibrational Spectroscopies as Tools for Small Molecule Biosensing

    Directory of Open Access Journals (Sweden)

    Souhir Boujday

    2015-08-01

    Full Text Available In this short summary we summarize some of the latest developments in vibrational spectroscopic tools applied for the sensing of (small molecules and biomolecules in a label-free mode of operation. We first introduce various concepts for the enhancement of InfraRed spectroscopic techniques, including the principles of Attenuated Total Reflection InfraRed (ATR-IR, (phase-modulated InfraRed Reflection Absorption Spectroscopy (IRRAS/PM-IRRAS, and Surface Enhanced Infrared Reflection Absorption Spectroscopy (SEIRAS. Particular attention is put on the use of novel nanostructured substrates that allow for the excitation of propagating and localized surface plasmon modes aimed at operating additional enhancement mechanisms. This is then be complemented by the description of the latest development in Surface- and Tip-Enhanced Raman Spectroscopies, again with an emphasis on the detection of small molecules or bioanalytes.

  8. Technical-technological aspects of using machines and tools for new technologies in plant production

    Directory of Open Access Journals (Sweden)

    Ercegović Đuro

    2009-01-01

    Full Text Available Agricultural production is complex process and it depends of various factors which can be controlled. Many of them can be improved by using of various means which are not friendly for environment and health of people. It is necessary to apply only those measures which can maintain and improve physical - mechanical, technological and microbiological properties of soil and also the nutritive potential of soil but will not be harmful for environment. The other part of this story demands decrease of energy necessary in the process of soil preparation. The machinery and tools for new technologies in plant production in Serbia is consisted of: vibrating subsoiler VR-5(7, universal self propelled machine for soil arrangement USM-5, draining plough DP-4 and universal Scraper land leveler, and it is developed to apply changed new technologies of soil preparation. This study gives description of machines, tools and technologies necessary for soil preparation in Serbia; this means preparation of soil surface and depth, special note is given to preservation of environment and improvement of soil potential, but also and how to decrease the energy necessary for the process of soil preparation.

  9. Synthesis of parameters of a machine set, according to amplitudes of vibration, in the case of coaxial misalignment of shafts

    Science.gov (United States)

    Rondomanskas, M. S.; Ragulskis, K. M.; Ionushas, R. A.; Bansevichyus, R. Y.

    1973-01-01

    Dynamic synthesis of the coupling parameters permits the building of coaxially aligned connected machines with very small disturbing forces. Considered is the case of two machines connected by a flexible coupling; one machine is installed on shock absorbers with four degrees of freedom. A movement leveling synthesis considers the coaxial nonalignment parameters for the shaft arrangement and determines the optimum coupling rigidity at which the vibration amplitude is at a minimum.

  10. Machinability of Green Powder Metallurgy Components: Part I. Characterization of the Influence of Tool Wear

    Science.gov (United States)

    Robert-Perron, Etienne; Blais, Carl; Pelletier, Sylvain; Thomas, Yannig

    2007-06-01

    The green machining process is an interesting approach for solving the mediocre machining behavior of high-performance powder metallurgy (PM) steels. This process appears as a promising method for extending tool life and reducing machining costs. Recent improvements in binder/lubricant technologies have led to high green strength systems that enable green machining. So far, tool wear has been considered negligible when characterizing the machinability of green PM specimens. This inaccurate assumption may lead to the selection of suboptimum cutting conditions. The first part of this study involves the optimization of the machining parameters to minimize the effects of tool wear on the machinability in turning of green PM components. The second part of our work compares the sintered mechanical properties of components machined in green state with other machined after sintering.

  11. Tool wear of a single-crystal diamond tool in nano-groove machining of a quartz glass plate

    Science.gov (United States)

    Yoshino, Masahiko; Nakajima, Satoshi; Terano, Motoki

    2015-12-01

    Tool wear characteristics of a diamond tool in ductile mode machining are presented in this paper. Nano-groove machining of a quartz glass plate was conducted to examine the tool wear rate of a single-crystal diamond tool. Effects of lubrication on the tool wear rate were also evaluated. A numerical simulation technique was developed to evaluate the tool temperature and normal stress acting on the wear surface. From the simulation results it was found that the tool temperature does not increase during the machining experiment. It is also demonstrated that tool wear is attributed to the abrasive wear mechanism, but the effect of the adhesion wear mechanism is minor in nano-groove machining. It is found that the tool wear rate is reduced by using water or kerosene as a lubricant.

  12. Simultaneous Scheduling of Jobs, AGVs and Tools Considering Tool Transfer Times in Multi Machine FMS By SOS Algorithm

    Science.gov (United States)

    Sivarami Reddy, N.; Ramamurthy, D. V., Dr.; Prahlada Rao, K., Dr.

    2017-08-01

    This article addresses simultaneous scheduling of machines, AGVs and tools where machines are allowed to share the tools considering transfer times of jobs and tools between machines, to generate best optimal sequences that minimize makespan in a multi-machine Flexible Manufacturing System (FMS). Performance of FMS is expected to improve by effective utilization of its resources, by proper integration and synchronization of their scheduling. Symbiotic Organisms Search (SOS) algorithm is a potent tool which is a better alternative for solving optimization problems like scheduling and proven itself. The proposed SOS algorithm is tested on 22 job sets with makespan as objective for scheduling of machines and tools where machines are allowed to share tools without considering transfer times of jobs and tools and the results are compared with the results of existing methods. The results show that the SOS has outperformed. The same SOS algorithm is used for simultaneous scheduling of machines, AGVs and tools where machines are allowed to share tools considering transfer times of jobs and tools to determine the best optimal sequences that minimize makespan.

  13. Machine Fault Detection Based on Filter Bank Similarity Features Using Acoustic and Vibration Analysis

    Directory of Open Access Journals (Sweden)

    Mauricio Holguín-Londoño

    2016-01-01

    Full Text Available Vibration and acoustic analysis actively support the nondestructive and noninvasive fault diagnostics of rotating machines at early stages. Nonetheless, the acoustic signal is less used because of its vulnerability to external interferences, hindering an efficient and robust analysis for condition monitoring (CM. This paper presents a novel methodology to characterize different failure signatures from rotating machines using either acoustic or vibration signals. Firstly, the signal is decomposed into several narrow-band spectral components applying different filter bank methods such as empirical mode decomposition, wavelet packet transform, and Fourier-based filtering. Secondly, a feature set is built using a proposed similarity measure termed cumulative spectral density index and used to estimate the mutual statistical dependence between each bandwidth-limited component and the raw signal. Finally, a classification scheme is carried out to distinguish the different types of faults. The methodology is tested in two laboratory experiments, including turbine blade degradation and rolling element bearing faults. The robustness of our approach is validated contaminating the signal with several levels of additive white Gaussian noise, obtaining high-performance outcomes that make the usage of vibration, acoustic, and vibroacoustic measurements in different applications comparable. As a result, the proposed fault detection based on filter bank similarity features is a promising methodology to implement in CM of rotating machinery, even using measurements with low signal-to-noise ratio.

  14. 76 FR 5832 - International Business Machines (IBM), Software Group Business Unit, Optim Data Studio Tools QA...

    Science.gov (United States)

    2011-02-02

    ... From the Federal Register Online via the Government Publishing Office DEPARTMENT OF LABOR Employment and Training Administration International Business Machines (IBM), Software Group Business Unit... at International Business Machines (IBM), Software Group Business Unit, Optim Data Studio Tools...

  15. The Fuzzy Cluster Analysis in Identification of Key Temperatures in Machine Tool

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The thermal-induced error is a very important sour ce of machining errors of machine tools. To compensate the thermal-induced machin ing errors, a relationship model between the thermal field and deformations was needed. The relationship can be deduced by virtual of FEM (Finite Element Method ), ANN (Artificial Neural Network) or MRA (Multiple Regression Analysis). MR A is on the basis of a total understanding of the temperature distribution of th e machine tool. Although the more the temperatures measu...

  16. Study on the influence of fluid application parameters on tool vibration and cutting performance during turning of hardened steel

    Directory of Open Access Journals (Sweden)

    P. Sam Paul

    2016-03-01

    Full Text Available Recently the concept of hard turning has gained much attention in the metal cutting industry. In hard turning, multiple operations can be performed in single step, thereby it replaces the traditional process cycle. But it involves very large quantities of cutting fluid. Procurement, storage and disposal of cutting fluid involve expenses and environmental problem. Pure dry turning is a solution to this problem as it does not require any cutting fluid at all. But pure dry turning requires ultra hard cutting tools and extremely rigid machine tools, and also it is difficult to implement in the existing shop floor as the machine tool may not be rigid enough to support hard turning. In this context, turning with minimal fluid application is a viable alternative wherein, extremely small quantities of cutting fluid are introduced at critical contact zones as high velocity pulsing slugs, so that for all practical purposes it resembles pure dry turning and at the same time free from all the problems related to large scale use of cutting fluid as in conventional wet turning. In this study, fluid application parameters that characterize the minimal fluid application scheme were optimized and its effect on cutting performance and tool vibration was studied. From the results, it was observed that minimal fluid application in the optimized mode brought forth low vibration levels and better cutting performance.

  17. Observation of SERS effect in Raman optical activity, a new tool for chiral vibrational spectroscopy

    DEFF Research Database (Denmark)

    Abdali, Salim

    2006-01-01

    A new tool for chiral vibrational spectroscopy is here reported. A Surface Enhanced effect was observed using Raman Optical Activity (ROA). This observation opens new possibilities for ROA as a tool for vibrational spectroscopy. The combination of surface enhanced effect SE and ROA into SEROA...

  18. Identification of Kinematic Errors of Five-axis Machine Tool Trunnion Axis from Finished Test Piece

    Institute of Scientific and Technical Information of China (English)

    ZHANG Ya; FU Jianzhong; CHEN Zichen

    2014-01-01

    Compared with the traditional non-cutting measurement, machining tests can more accurately reflect the kinematic errors of five-axis machine tools in the actual machining process for the users. However, measurement and calculation of the machining tests in the literature are quite difficult and time-consuming. A new method of the machining tests for the trunnion axis of five-axis machine tool is proposed. Firstly, a simple mathematical model of the cradle-type five-axis machine tool was established by optimizing the coordinate system settings based on robot kinematics. Then, the machining tests based on error-sensitive directions were proposed to identify the kinematic errors of the trunnion axis of cradle-type five-axis machine tool. By adopting the error-sensitive vectors in the matrix calculation, the functional relationship equations between the machining errors of the test piece in the error-sensitive directions and the kinematic errors of C-axis and A-axis of five-axis machine tool rotary table was established based on the model of the kinematic errors. According to our previous work, the kinematic errors of C-axis can be treated as the known quantities, and the kinematic errors of A-axis can be obtained from the equations. This method was tested in Mikron UCP600 vertical machining center. The machining errors in the error-sensitive directions can be obtained by CMM inspection from the finished test piece to identify the kinematic errors of five-axis machine tool trunnion axis. Experimental results demonstrated that the proposed method can reduce the complexity, cost, and the time consumed substantially, and has a wider applicability. This paper proposes a new method of the machining tests for the trunnion axis of five-axis machine tool.

  19. Prospects for chaos control of machine tool chatter

    Energy Technology Data Exchange (ETDEWEB)

    Hively, L.M.; Protopopescu, V.A.; Clapp, N.E.; Daw, C.S.

    1998-06-01

    The authors analyze the nonlinear tool-part dynamics during turning of stainless steel in the nonchatter and chatter regimes, toward the ultimate objective of chatter control. Their previous work analyzed tool acceleration in three dimensions at four spindle speeds. In the present work, the authors analyze the machining power and obtain nonlinear measures of this power. They also calculate the cycle-to-cycle energy for the turning process. Return maps for power cycle times do not reveal fixed points or (un)stable manifolds. Energy return maps do display stable and unstable directions (manifolds) to and from an unstable period-1 orbit, which is the dominant periodicity. Both nonchatter and chatter dynamics have the unusual feature of arriving at the unstable period-1 fixed point and departing from that fixed point of the energy return map in a single step. This unusual feature makes chaos maintenance, based on the well-known Ott-Grebogi-Yorke scheme, a very difficult option for chatter suppression. Alternative control schemes, such as synchronization of the tool-part motion to prerecorded nonchatter dynamics or dynamically damping the period-1 motion, are briefly discussed.

  20. Fiber optic vibration sensor for high-power electric machines realized using 3D printing technology

    Science.gov (United States)

    Igrec, Bojan; Bosiljevac, Marko; Sipus, Zvonimir; Babic, Dubravko; Rudan, Smiljko

    2016-03-01

    The objective of this work was to demonstrate a lightweight and inexpensive fiber-optic vibration sensor, built using 3D printing technology, for high-power electric machines and similar applications. The working principle is based on modulating the light intensity using a blade attached to a bendable membrane. The sensor prototype was manufactured using PolyJet Matrix technology with DM 8515 Grey 35 Polymer. The sensor shows linear response, expected bandwidth (< 150 Hz), and from our measurements we estimated the damping ratio for used polymer to be ζ ≍ 0.019. The developed prototype is simple to assemble, adjust, calibrate and repair.

  1. Modeling of tool path for the CNC sheet cutting machines

    Science.gov (United States)

    Petunin, Aleksandr A.

    2015-11-01

    In the paper the problem of tool path optimization for CNC (Computer Numerical Control) cutting machines is considered. The classification of the cutting techniques is offered. We also propose a new classification of toll path problems. The tasks of cost minimization and time minimization for standard cutting technique (Continuous Cutting Problem, CCP) and for one of non-standard cutting techniques (Segment Continuous Cutting Problem, SCCP) are formalized. We show that the optimization tasks can be interpreted as discrete optimization problem (generalized travel salesman problem with additional constraints, GTSP). Formalization of some constraints for these tasks is described. For the solution GTSP we offer to use mathematical model of Prof. Chentsov based on concept of a megalopolis and dynamic programming.

  2. Small machine tools for small workpieces final report of the DFG priority program 1476

    CERN Document Server

    Sanders, Adam

    2017-01-01

    This contributed volume presents the research results of the program “Small machine tools for small work pieces” (SPP 1476), funded by the German Research Society (DFG). The book contains the final report of the priority program, presenting novel approached for size-adapted, reconfigurable micro machine tools. The target audience primarily comprises research experts and practitioners in the field of micro machine tools, but the book may also be beneficial for graduate students.

  3. Development of hardware system using temperature and vibration maintenance models integration concepts for conventional machines monitoring: a case study

    Science.gov (United States)

    Adeyeri, Michael Kanisuru; Mpofu, Khumbulani; Kareem, Buliaminu

    2016-12-01

    This article describes the integration of temperature and vibration models for maintenance monitoring of conventional machinery parts in which their optimal and best functionalities are affected by abnormal changes in temperature and vibration values thereby resulting in machine failures, machines breakdown, poor quality of products, inability to meeting customers' demand, poor inventory control and just to mention a few. The work entails the use of temperature and vibration sensors as monitoring probes programmed in microcontroller using C language. The developed hardware consists of vibration sensor of ADXL345, temperature sensor of AD594/595 of type K thermocouple, microcontroller, graphic liquid crystal display, real time clock, etc. The hardware is divided into two: one is based at the workstation (majorly meant to monitor machines behaviour) and the other at the base station (meant to receive transmission of machines information sent from the workstation), working cooperatively for effective functionalities. The resulting hardware built was calibrated, tested using model verification and validated through principles pivoted on least square and regression analysis approach using data read from the gear boxes of extruding and cutting machines used for polyethylene bag production. The results got therein confirmed related correlation existing between time, vibration and temperature, which are reflections of effective formulation of the developed concept.

  4. Vibration transmitted to operator’s back by machines with back-pack power unit: a case study on blower and spraying machines

    Directory of Open Access Journals (Sweden)

    Roberto Deboli

    2013-09-01

    Full Text Available To correctly evaluate the vibration transmitted to the operators, it is necessary to consider each body’s point interested by the vibratory stimulus produced by machines. All the body’s part in contact to the vibration, when a portable device with internal combustion engine is used, are: hands, back and shoulders. Some information for wholebody vibration are available in the ISO 2631-1997 standard, which otherwise refers to a seated operator. ‘C’ type standards for the vibration analysis exist for some portable machines with an internal combustion engine which is comprehensive in the machine (chainsaw, brush-cutter, blower. If the engine is not inside the machine, but it is on the operator’s back, ‘C’ type standards on vibration measurements are quite incomplete. The IMAMOTER institute of CNR, the DISAFA Department (University of Turin and the Occupational Medicine Department of the University of Catania started some tests to verify the vibration levels transmitted to an operator working with backed engine devices. Two machines have been examined: a blower and a spraying machine. Two operative conditions have been considered during all the tests: idling and full load. Three operators have been involved and each test has been repeated three times. The spraying machine has been tested both with the empty tank and with 10 litres of water, to simulate the load to be caused by the presence of liquid inside the tank. In this work the comfort condition of ISO 2631-1 standard was considered, using the frequency weighting Wc curve with the weighting factor 0.8 for X axis (back-ventral direction and the Wd curve for Y and Z axis (shoulder - shoulder and buttocks - head with weighting factors 0.5 and 0.4 (respectively for Y and Z axis. Data were examined using IBM SPSS Statistics 20 software package. The statistical analysis underlined that the running condition is the main factor to condition the vibration levels transmitted to the operator

  5. Actualities and Development of Heavy-Duty CNC Machine Tool Thermal Error Monitoring Technology

    Science.gov (United States)

    Zhou, Zu-De; Gui, Lin; Tan, Yue-Gang; Liu, Ming-Yao; Liu, Yi; Li, Rui-Ya

    2017-09-01

    Thermal error monitoring technology is the key technological support to solve the thermal error problem of heavy-duty CNC (computer numerical control) machine tools. Currently, there are many review literatures introducing the thermal error research of CNC machine tools, but those mainly focus on the thermal issues in small and medium-sized CNC machine tools and seldom introduce thermal error monitoring technologies. This paper gives an overview of the research on the thermal error of CNC machine tools and emphasizes the study of thermal error of the heavy-duty CNC machine tool in three areas. These areas are the causes of thermal error of heavy-duty CNC machine tool and the issues with the temperature monitoring technology and thermal deformation monitoring technology. A new optical measurement technology called the "fiber Bragg grating (FBG) distributed sensing technology" for heavy-duty CNC machine tools is introduced in detail. This technology forms an intelligent sensing and monitoring system for heavy-duty CNC machine tools. This paper fills in the blank of this kind of review articles to guide the development of this industry field and opens up new areas of research on the heavy-duty CNC machine tool thermal error.

  6. Modulated Tool-Path Chip Breaking For Depleted Uranium Machining Operations

    Energy Technology Data Exchange (ETDEWEB)

    Barkman, W. E.; Babelay Jr., E. F.; Smith, K. S.; Assaid T. S.; McFarland, J. T.; Tursky, D. A.

    2010-04-15

    Turning operations involving depleted uranium frequently generate long, stringy chips that present a hazard to both the machinist and the machine tool. While a variety of chip-breaking techniques are available, they generally depend on a mechanism that increases the bending of the chip or the introduction of a one dimensional vibration that produces an interrupted cutting pattern. Unfortunately, neither of these approaches is particularly effective when making a 'light depth-of-cut' on a contoured workpiece. The historical solution to this problem has been for the machinist to use long-handled tweezers to 'pull the chip' and try to keep it submerged in the chip pan; however, this approach is not practical for all machining operations. This paper discusses a research project involving the Y-12 National Security Complex and the University of North Carolina at Charlotte in which unique, oscillatory part programs are used to continuously create an interrupted cut that generates pre-defined, user-selectable chip lengths.

  7. Kinematic Analysis of a New Parallel Machine Tool: the Orthoglide

    CERN Document Server

    Wenger, Philippe

    2007-01-01

    This paper describes a new parallel kinematic architecture for machining applications: the orthoglide. This machine features three fixed parallel linear joints which are mounted orthogonally and a mobile platform which moves in the Cartesian x-y-z space with fixed orientation. The main interest of the orthoglide is that it takes benefit from the advantages of the popular PPP serial machines (regular Cartesian workspace shape and uniform performances) as well as from the parallel kinematic arrangement of the links (less inertia and better dynamic performances), which makes the orthoglide well suited to high-speed machining applications. Possible extension of the orthoglide to 5-axis machining is also investigated.

  8. Using the Spindle Cooling Temperature as a Tool for Compensating the Thermal Deformation of Machines

    Directory of Open Access Journals (Sweden)

    J. Vyroubal

    2010-01-01

    Full Text Available Thermal error compensation of machine tools is a relatively complex problem nowadays. Machine users have very high expectations, and it is necessary to use all means to improve the cutting accuracy of existing machines. This paper deals with a novel approach, which combines standard temperature measurement of a machine tool and new temperature measurement of the spindle cooling liquid. A multinomial regression equation is then used to calculate the compensation correction of the position of the tool. This calculation does not critically overload the control system of the machines, so no external computing hardware is required. The cooling liquid approach improves the accuracy of the machine tool over an operational time of several hours. 

  9. Application of Krylov Reduction Technique for a Machine Tool Multibody Modelling

    Directory of Open Access Journals (Sweden)

    M. Sulitka

    2014-02-01

    Full Text Available Quick calculation of machine tool dynamic response represents one of the major requirements for machine tool virtual modelling and virtual machining, aiming at simulating the machining process performance, quality, and precision of a workpiece. Enhanced time effectiveness in machine tool dynamic simulations may be achieved by employing model order reduction (MOR techniques of the full finite element (FE models. The paper provides a case study aimed at comparison of Krylov subspace base and mode truncation technique. Application of both of the reduction techniques for creating a machine tool multibody model is evaluated. The Krylov subspace reduction technique shows high quality in terms of both dynamic properties of the reduced multibody model and very low time demands at the same time.

  10. 数控机床产业强势增长%Robust growth of NC machine tool industry

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    @@ The machine tool industry is an industry which provides production equipment for the equipment manufacturing industry, and the machine tool is the parent machine for equipment manufacturing, playing a key part in the industry.The equipment manufacturing industry, for example, the automobile industry, uses more than 60% of its fixed asset investment in the purchase of machine tools.The numerical control (NC)machine tool, as a mainstream product of the machine tool sector, has become a key piece of equipment for achieving modernisation of equipment manufacturing.It is the realistic requirement to speed up development of NC machine production for the development of China's equipment manufacturing industry.

  11. Advancing Research in Second Language Writing through Computational Tools and Machine Learning Techniques: A Research Agenda

    Science.gov (United States)

    Crossley, Scott A.

    2013-01-01

    This paper provides an agenda for replication studies focusing on second language (L2) writing and the use of natural language processing (NLP) tools and machine learning algorithms. Specifically, it introduces a range of the available NLP tools and machine learning algorithms and demonstrates how these could be used to replicate seminal studies…

  12. Machine and Woodworking Tool Safety. Module SH-24. Safety and Health.

    Science.gov (United States)

    Center for Occupational Research and Development, Inc., Waco, TX.

    This student module on machine and woodworking tool safety is one of 50 modules concerned with job safety and health. This module discusses specific practices and precautions concerned with the efficient operation and use of most machine and woodworking tools in use today. Following the introduction, 13 objectives (each keyed to a page in the…

  13. 75 FR 65516 - ASC Machine Tools, Inc., Spokane Valley, WA; Notice of Affirmative Determination Regarding...

    Science.gov (United States)

    2010-10-25

    ... Employment and Training Administration ASC Machine Tools, Inc., Spokane Valley, WA; Notice of Affirmative... apply for Trade Adjustment Assistance (TAA) applicable to workers and former workers of ASC Machine Tools, Inc., Spokane Valley, Washington (the subject firm). The Notice of negative determination...

  14. Advancing Research in Second Language Writing through Computational Tools and Machine Learning Techniques: A Research Agenda

    Science.gov (United States)

    Crossley, Scott A.

    2013-01-01

    This paper provides an agenda for replication studies focusing on second language (L2) writing and the use of natural language processing (NLP) tools and machine learning algorithms. Specifically, it introduces a range of the available NLP tools and machine learning algorithms and demonstrates how these could be used to replicate seminal studies…

  15. Application of Maintenance Simulate System of NC Machine Tools in Teaching

    Directory of Open Access Journals (Sweden)

    He Xin

    2017-01-01

    Full Text Available The project design is the foundation of training, which can insure the usefulness of human resource development system. The Training Project Maintenance Simulate System of NC Machine Tools is presented based on analyzed contradiction between supply and demand. This paper introduces several scheme of Maintenance Simulate System of NC Machine Tools.

  16. Static Stiffness Modeling of a Novel PKM-Machine Tool Structure

    Directory of Open Access Journals (Sweden)

    O. K. Akmaev

    2014-07-01

    Full Text Available This article presents a new configuration of a 3-dof machine tool with parallel kinematics. Elastic deformations of the machine tool have been modeled with finite elements, stiffness coefficients at characteristic points of the working area for different cutting forces have been calculated.

  17. Vibration Monitoring of Gas Turbine Engines: Machine-Learning Approaches and Their Challenges

    Directory of Open Access Journals (Sweden)

    Ioannis Matthaiou

    2017-09-01

    Full Text Available In this study, condition monitoring strategies are examined for gas turbine engines using vibration data. The focus is on data-driven approaches, for this reason a novelty detection framework is considered for the development of reliable data-driven models that can describe the underlying relationships of the processes taking place during an engine’s operation. From a data analysis perspective, the high dimensionality of features extracted and the data complexity are two problems that need to be dealt with throughout analyses of this type. The latter refers to the fact that the healthy engine state data can be non-stationary. To address this, the implementation of the wavelet transform is examined to get a set of features from vibration signals that describe the non-stationary parts. The problem of high dimensionality of the features is addressed by “compressing” them using the kernel principal component analysis so that more meaningful, lower-dimensional features can be used to train the pattern recognition algorithms. For feature discrimination, a novelty detection scheme that is based on the one-class support vector machine (OCSVM algorithm is chosen for investigation. The main advantage, when compared to other pattern recognition algorithms, is that the learning problem is being cast as a quadratic program. The developed condition monitoring strategy can be applied for detecting excessive vibration levels that can lead to engine component failure. Here, we demonstrate its performance on vibration data from an experimental gas turbine engine operating on different conditions. Engine vibration data that are designated as belonging to the engine’s “normal” condition correspond to fuels and air-to-fuel ratio combinations, in which the engine experienced low levels of vibration. Results demonstrate that such novelty detection schemes can achieve a satisfactory validation accuracy through appropriate selection of two parameters of the

  18. Effects of machining parameters on tool life and its optimization in turning mild steel with brazed carbide cutting tool

    Science.gov (United States)

    Dasgupta, S.; Mukherjee, S.

    2016-09-01

    One of the most significant factors in metal cutting is tool life. In this research work, the effects of machining parameters on tool under wet machining environment were studied. Tool life characteristics of brazed carbide cutting tool machined against mild steel and optimization of machining parameters based on Taguchi design of experiments were examined. The experiments were conducted using three factors, spindle speed, feed rate and depth of cut each having three levels. Nine experiments were performed on a high speed semi-automatic precision central lathe. ANOVA was used to determine the level of importance of the machining parameters on tool life. The optimum machining parameter combination was obtained by the analysis of S/N ratio. A mathematical model based on multiple regression analysis was developed to predict the tool life. Taguchi's orthogonal array analysis revealed the optimal combination of parameters at lower levels of spindle speed, feed rate and depth of cut which are 550 rpm, 0.2 mm/rev and 0.5mm respectively. The Main Effects plot reiterated the same. The variation of tool life with different process parameters has been plotted. Feed rate has the most significant effect on tool life followed by spindle speed and depth of cut.

  19. The Electrical and Mechanical Alignment and Accuracy Detection of Numerial Control Machine Tool

    Institute of Scientific and Technical Information of China (English)

    XU Liang-xiong; ZHOU Xiang

    2012-01-01

    In the work of numerical control reformation of general machine tool, the installation and debugging of machine tool is a crucial part. For the C6132 machine tool, and make the use of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been used to finish a series of tailing in the work of numerical control reformation of general machine tool. In this paper, the detailed process of electrical and mechanical alignment, parameter adjusting, numerical control lathe accuracy debugging and performance examination has been demonstrated, meanwhile, the specific operational approach of these work programs has been discussed. Therefore, the present results provides essential reference and approach for the numerical control reformation of general machine tool.

  20. 3-PRS serial-parallel machine tool error calibration and parameter identification

    Institute of Scientific and Technical Information of China (English)

    ZHAO Jun-wei; DAI Jun; HUANG Jun-jie

    2009-01-01

    3-PRS serial-parallel machine tool consists of a 3-degree-of-freedom (DOF) implementation platform and a 2-DOF X-Y platform. The error modeling and parameter identification methods were deduced based on 3-PRS serial-parallel machine tool. 3-PRS serial-parallel machine tool was researched, and the mechanism of error analysis, modeling, identification of error parameters and measurement equipment for the use of agency error of measurement were conducted. In order to achieve the geometric parameters calibration and error compensation of the serial-parallel machine tool, the nominal structural parameters of the controller was adjusted by identifying the structure of the machine tool. With the establishment of a vector space size chain, we can do the error analysis, error modeling, error measurement and error compensation can be done.

  1. Development of meso-scale milling machine tool and its performance analysis

    Institute of Scientific and Technical Information of China (English)

    Hongtao LI; Xinmin LAI; Chengfeng LI; Zhongqin LIN; Jiancheng MIAO; Jun NI

    2008-01-01

    To overcome the shortcomings of current technologies for meso-scale manufacturing such as MEMS and ultra precision machining, this paper focuses on the investigations on the meso milling process with a miniaturized machine tool. First, the related technologies for the process mechanism studies are investigated based on the analysis of the characteristics of the meso milling process. An overview of the key issues is presented and research approaches are also proposed. Then, a meso-scale milling machine tool system is developed. The subsystems and their specifications are described in detail. Finally, some tests are conducted to evaluate the performance of the system. These tests consist of precision measurement of the positioning subsystem, the test for machining precision evaluation, and the experiments for machining mechanical parts with com-plex features. Through test analysis, the meso milling process with a miniaturized machine tool is proved to be feasible and applicable for meso manufacturing.

  2. VIBRATION SENSORS AND MICROELECTROMECHANICAL SYSTEM FOR MOBILE DEVICES SUCH AS ANALOGS, FOR EVALUATION OF VIBRATION OF ROTARY MACHINES

    Directory of Open Access Journals (Sweden)

    2016-01-01

    Full Text Available The paper carried out a comparison of vibration sensors used to measure the vibration condition units with gas turbine engines, with motion sensors, microelectromechanical systems used in modern mobile devices (for example, devices on the platform "Android". It provides opinions on the possibility of assessment of vibration, using sensors of mobile devices.

  3. Correlation between vibration amplitude and tool wear in turning: Numerical and experimental analysis

    National Research Council Canada - National Science Library

    Prasad, Balla Srinivasa; Babu, M. Prakash

    In this paper, a correlation between vibration amplitude and tool wear when in dry turning of AISI 4140 steel using uncoated carbide insert DNMA 432 is analyzed via experiments and finite element simulations...

  4. The development of a two-component force dynamometer and tool control system for dynamic machine tool research

    Science.gov (United States)

    Sutherland, I. A.

    1973-01-01

    The development is presented of a tooling system that makes a controlled sinusoidal oscillation simulating a dynamic chip removal condition. It also measures the machining forces in two mutually perpendicular directions without any cross sensitivity.

  5. Fourier transform based dynamic error modeling method for ultra-precision machine tool

    Science.gov (United States)

    Chen, Guoda; Liang, Yingchun; Ehmann, Kornel F.; Sun, Yazhou; Bai, Qingshun

    2014-08-01

    In some industrial fields, the workpiece surface need to meet not only the demand of surface roughness, but the strict requirement of multi-scale frequency domain errors. Ultra-precision machine tool is the most important carrier for the ultra-precision machining of the parts, whose errors is the key factor to influence the multi-scale frequency domain errors of the machined surface. The volumetric error modeling is the important bridge to link the relationship between the machine error and machined surface error. However, the available error modeling method from the previous research is hard to use to analyze the relationship between the dynamic errors of the machine motion components and multi-scale frequency domain errors of the machined surface, which plays the important reference role in the design and accuracy improvement of the ultra-precision machine tool. In this paper, a fourier transform based dynamic error modeling method is presented, which is also on the theoretical basis of rigid body kinematics and homogeneous transformation matrix. A case study is carried out, which shows the proposed method can successfully realize the identical and regular numerical description of the machine dynamic errors and the volumetric errors. The proposed method has strong potential for the prediction of the frequency domain errors on the machined surface, extracting of the information of multi-scale frequency domain errors, and analysis of the relationship between the machine motion components and frequency domain errors of the machined surface.

  6. Haptics-Augmented Simple-Machine Educational Tools.

    Science.gov (United States)

    Williams, Robert L., II; Chen, Meng-Yun; Seaton, Jeffrey M.

    2003-01-01

    Describes a unique project using commercial haptic interfaces to augment the teaching of simple machines in elementary school. Suggests that the use of haptics in virtual simple-machine simulations has the potential for deeper, more engaging learning. (Contains 13 references.) (Author/YDS)

  7. Performance investigation of capillary tubes for machine tool coolers retrofitted with HFC-407C refrigerant

    Science.gov (United States)

    Wang, Fujen; Chang, Tongbou; Chiang, Weiming; Lee, Haochung

    2012-09-01

    The machine tool coolers are the best managers of coolant temperature in avoiding the deviation of spindle centerline for machine tools. However, the machine coolers are facing the compressed schedule to phase out the HCFC (hydro-chloro-floro-carbon) refrigerant and little attention has been paid to comparative study on sizing capillary tube for retrofitted HFC (hydro-floro-carbon) refrigerant. In this paper, the adiabatic flow in capillary tube is analyzed and modeled for retrofitting of HFC-407C refrigerant in a machine tool cooler system. A computer code including determining the length of sub-cooled flow region and the two phase region of capillary tube is developed. Comparative study of HCFC-22 and HFC-407C in a capillary tube is derived and conducted to simplify the traditional trial-and-error method of predicting the length of capillary tubes. Besides, experimental investigation is carried out by field tests to verify the simulation model and cooling performance of the machine tool cooler system. The results from the experiments reveal that the numerical model provides an effective approach to determine the performance data of capillary tube specific for retrofitting a HFC-407C machine tool cooler. The developed machine tool cooler system is not only directly compatible with new HFC-407C refrigerant, but can also perform a cost-effective temperature control specific for industrial machines.

  8. Application of Artificial Intelligence Methods of Tool Path Optimization in CNC Machines: A Review

    Directory of Open Access Journals (Sweden)

    Khashayar Danesh Narooei

    2014-08-01

    Full Text Available Today, in most of metal machining process, Computer Numerical Control (CNC machine tools have been very popular due to their efficiencies and repeatability to achieve high accuracy positioning. One of the factors that govern the productivity is the tool path travel during cutting a work piece. It has been proved that determination of optimal cutting parameters can enhance the machining results to reach high efficiency and minimum the machining cost. In various publication and articles, scientist and researchers adapted several Artificial Intelligence (AI methods or hybrid method for tool path optimization such as Genetic Algorithms (GA, Artificial Neural Network (ANN, Artificial Immune Systems (AIS, Ant Colony Optimization (ACO and Particle Swarm Optimization (PSO. This study presents a review of researches in tool path optimization with different types of AI methods that show the capability of using different types of optimization methods in CNC machining process.

  9. CPS Modeling of CNC Machine Tool Work Processes Using an Instruction-Domain Based Approach

    Directory of Open Access Journals (Sweden)

    Jihong Chen

    2015-06-01

    Full Text Available Building cyber-physical system (CPS models of machine tools is a key technology for intelligent manufacturing. The massive electronic data from a computer numerical control (CNC system during the work processes of a CNC machine tool is the main source of the big data on which a CPS model is established. In this work-process model, a method based on instruction domain is applied to analyze the electronic big data, and a quantitative description of the numerical control (NC processes is built according to the G code of the processes. Utilizing the instruction domain, a work-process CPS model is established on the basis of the accurate, real-time mapping of the manufacturing tasks, resources, and status of the CNC machine tool. Using such models, case studies are conducted on intelligent-machining applications, such as the optimization of NC processing parameters and the health assurance of CNC machine tools.

  10. NC flame pipe cutting machine tool based on open architecture CNC system

    Institute of Scientific and Technical Information of China (English)

    Xiaogen NIE; Yanbing LIU

    2009-01-01

    Based on the analysis of the principle and flame movement of a pipe cutting machine tool, a retrofit NC flame pipe cutting machine tool (NFPCM) that can meet the demands of cutting various pipes is proposed. The paper deals with the design and implementation of an open architecture CNC system for the NFPCM, many of whose aspects are similar to milling machines; however, different from their machining processes and control strategies. The paper emphasizes on the NC system structure and the method for directly creating the NC file according to the cutting type and parameters. Further, the paper develops the program and sets up the open and module NC system.

  11. On-line tool breakage monitoring of vibration tapping using spindle motor current

    Science.gov (United States)

    Li, Guangjun; Lu, Huimin; Liu, Gang

    2008-10-01

    Input current of driving motor has been employed successfully as monitoring the cutting state in manufacturing processes for more than a decade. In vibration tapping, however, the method of on-line monitoring motor electric current has not been reported. In this paper, a tap failure prediction method is proposed to monitor the vibration tapping process using the electrical current signal of the spindle motor. The process of vibration tapping is firstly described. Then the relationship between the torque of vibration tapping and the electric current of motor is investigated by theoretic deducing and experimental measurement. According to those results, a monitoring method of tool's breakage is proposed through monitoring the ratio of the current amplitudes during adjacent vibration tapping periods. Finally, a low frequency vibration tapping system with motor current monitoring is built up using a servo motor B-106B and its driver CR06. The proposed method has been demonstrated with experiment data of vibration tapping in titanic alloys. The result of experiments shows that the method, which can avoid the tool breakage and giving a few error alarms when the threshold of amplitude ratio is 1.2 and there is at least 2 times overrun among 50 adjacent periods, is feasible for tool breakage monitoring in the process of vibration tapping small thread holes.

  12. Instantaneous Purified Orbit: A New Tool for Analysis of Nonstationary Vibration of Rotor System

    Directory of Open Access Journals (Sweden)

    Shi Dongfeng

    2001-01-01

    Full Text Available In some circumstances, vibration signals of large rotating machinery possess time-varying characteristics to some extent. Traditional diagnosis methods, such as FFT spectrum and orbit diagram, are confronted with a huge challenge to deal with this problem. This work aims at studying the four intrinsic drawbacks of conventional vibration signal processing method and instantaneous purified orbit (IPO on the basis of improved Fourier spectrum (IFS to analyze nonstationary vibration. On account of integration, the benefits of short period Fourier transform (SPFT and regular holospectrum, this method can intuitively reflect vibration characteristics of’a rotor system by means of parameter analysis for corresponding frequency ellipses. Practical examples, such as transient vibration in run-up stages and bistable condition of rotor show that IPO is a powerful tool for diagnosis and analysis of the vibration behavior of rotor systems.

  13. The Development of LZG Spiral Vibration Drying Machine%LZG螺旋振动干燥机的研制

    Institute of Scientific and Technical Information of China (English)

    刘雄心; 李梦瑶; 谭铁仁; 高智; 刘明远

    2012-01-01

    依据我国国情北方降水少和北方玉米干燥的特点,研制了螺旋振动干燥机;介绍了螺旋振动干燥机及螺旋振动干燥成套设备的工作原理与特性;对干燥室干燥介质的消耗量进行了计算.%According to China's national conditions and the characteristics of the drying corn precipitation , the spiral vibration drying machine is developed; the working principles and characteristics of spiral vibration drying machine and complete equipment of spiral vibration drying are introduced; the consumption of media and its heat to dry in the dry room was calculated.

  14. An intelligent condition monitoring system for on-line classification of machine tool wear

    Energy Technology Data Exchange (ETDEWEB)

    Fu Pan; Hope, A.D.; Javed, M. [Systems Engineering Faculty, Southampton Institute (United Kingdom)

    1997-12-31

    The development of intelligent tool condition monitoring systems is a necessary requirement for successful automation of manufacturing processes. This presentation introduces a tool wear monitoring system for milling operations. The system utilizes power, force, acoustic emission and vibration sensors to monitor tool condition comprehensively. Features relevant to tool wear are drawn from time and frequency domain signals and a fuzzy pattern recognition technique is applied to combine the multisensor information and provide reliable classification results of tool wear states. (orig.) 10 refs.

  15. Smart Cutting Tools and Smart Machining: Development Approaches, and Their Implementation and Application Perspectives

    Science.gov (United States)

    Cheng, Kai; Niu, Zhi-Chao; Wang, Robin C.; Rakowski, Richard; Bateman, Richard

    2017-09-01

    Smart machining has tremendous potential and is becoming one of new generation high value precision manufacturing technologies in line with the advance of Industry 4.0 concepts. This paper presents some innovative design concepts and, in particular, the development of four types of smart cutting tools, including a force-based smart cutting tool, a temperature-based internally-cooled cutting tool, a fast tool servo (FTS) and smart collets for ultraprecision and micro manufacturing purposes. Implementation and application perspectives of these smart cutting tools are explored and discussed particularly for smart machining against a number of industrial application requirements. They are contamination-free machining, machining of tool-wear-prone Si-based infra-red devices and medical applications, high speed micro milling and micro drilling, etc. Furthermore, implementation techniques are presented focusing on: (a) plug-and-produce design principle and the associated smart control algorithms, (b) piezoelectric film and surface acoustic wave transducers to measure cutting forces in process, (c) critical cutting temperature control in real-time machining, (d) in-process calibration through machining trials, (e) FE-based design and analysis of smart cutting tools, and (f) application exemplars on adaptive smart machining.

  16. Motion and Virtual Cutting Simulation System for a Five-Axis Virtual Machine Tool

    Directory of Open Access Journals (Sweden)

    Rong-Shean Lee

    2011-09-01

    Full Text Available Since five-axis machine tools are very costly and their use requires a high level of knowledge and expertise, a virtual machine tool must be used to simulate five-axis machine tool operation. Configuration code or a mechanism topology matrix must be used to describe a machine tool, and can be used as the framework for design of a virtual machine tool system. The first step is to isolate the basic motions of each element of a virtual machine tool and then establish their coordinate systems. The establishment of a node tree allows coordinate transformation matrices for virtual motion components to be derived, which are then used to simulate movements. The simulation of virtual cutting must take into consideration both accuracy and efficiency. While either a GPU or CPU can be used to perform calculations, there are currently restrictions on GPU memory use which results in relatively lower accuracy. In contrast, a CPU can perform calculations using an adaptive octree with voxels and multithreading to yield sufficient accuracy and efficiency. A five-axis virtual machine tool motion and virtual cutting simulation system was written in C/C++ with OpenGL and OpenMP, and can perform real-time cutting simulations.

  17. MLBCD: a machine learning tool for big clinical data.

    Science.gov (United States)

    Luo, Gang

    2015-01-01

    Predictive modeling is fundamental for extracting value from large clinical data sets, or "big clinical data," advancing clinical research, and improving healthcare. Machine learning is a powerful approach to predictive modeling. Two factors make machine learning challenging for healthcare researchers. First, before training a machine learning model, the values of one or more model parameters called hyper-parameters must typically be specified. Due to their inexperience with machine learning, it is hard for healthcare researchers to choose an appropriate algorithm and hyper-parameter values. Second, many clinical data are stored in a special format. These data must be iteratively transformed into the relational table format before conducting predictive modeling. This transformation is time-consuming and requires computing expertise. This paper presents our vision for and design of MLBCD (Machine Learning for Big Clinical Data), a new software system aiming to address these challenges and facilitate building machine learning predictive models using big clinical data. The paper describes MLBCD's design in detail. By making machine learning accessible to healthcare researchers, MLBCD will open the use of big clinical data and increase the ability to foster biomedical discovery and improve care.

  18. Vibration reduction of pneumatic percussive rivet tools: mechanical and ergonomic re-design approaches.

    Science.gov (United States)

    Cherng, John G; Eksioglu, Mahmut; Kizilaslan, Kemal

    2009-03-01

    This paper presents a systematic design approach, which is the result of years of research effort, to ergonomic re-design of rivet tools, i.e. rivet hammers and bucking bars. The investigation was carried out using both ergonomic approach and mechanical analysis of the rivet tools dynamic behavior. The optimal mechanical design parameters of the re-designed rivet tools were determined by Taguchi method. Two ergonomically re-designed rivet tools with vibration damping/isolation mechanisms were tested against two conventional rivet tools in both laboratory and field tests. Vibration characteristics of both types of tools were measured by laboratory tests using a custom-made test fixture. The subjective field evaluations of the tools were performed by six experienced riveters at an aircraft repair shop. Results indicate that the isolation spring and polymer damper are very effective in reducing the overall level of vibration under both unweighted and weighted acceleration conditions. The mass of the dolly head and the housing played a significant role in the vibration absorption of the bucking bars. Another important result was that the duct iron has better vibration reducing capability compared to steel and aluminum for bucking bars. Mathematical simulation results were also consistent with the experimental results. Overall conclusion obtained from the study was that by applying the design principles of ergonomics and by adding vibration damping/isolation mechanisms to the rivet tools, the vibration level can significantly be reduced and the tools become safer and user friendly. The details of the experience learned, design modifications, test methods, mathematical models and the results are included in the paper.

  19. Inverse kinematics analysis and numerical control experiment for PRS-XY style hybrid machining tool

    Institute of Scientific and Technical Information of China (English)

    JIA Dongyong; ZHANG Jianmin; NIU Zhigang; SUN Hongchang

    2007-01-01

    This paper analyzed the inverse kinematics for the new Parallel rotate slider-X Y axes(PRS-XY)style hybrid machining tool and educed the five axes linkage inverse kinematics transform formula on the basis of the coordinates of the X,Y,Z,A and B virtual axes.The program for the PRS-XY style hybrid machining tool in accordance with the program manner for the common numerical control(NC)machine tool was made.The results of the experiments prove that the inverse kinematics transform formula is correct.

  20. Automated Parallel Computing Tools for Multicore Machines and Clusters Project

    Data.gov (United States)

    National Aeronautics and Space Administration — We propose to improve productivity of high performance computing for applications on multicore computers and clusters. These machines built from one or more chips...

  1. Adaptive control of mechatronic machine-tool equipment

    Directory of Open Access Journals (Sweden)

    R.G. Kudoyarov

    2015-09-01

    Full Text Available In this paper the method for designing a functional structure of mechatronic modules based on the developed classification of functional subsystems and the proposed turning machine modular structure is presented.

  2. Influence On Physical Work While Working With Segmental Vibration Inducing Hand Operated Power Tools

    Directory of Open Access Journals (Sweden)

    Sudhir Vinayakrao. Deshmukh

    2012-10-01

    Full Text Available Study evaluates and assesses the work done by vibrating equipments. It includes the assessment of influence of various independent variables associated with hand tools, operators, work & environmental factors on various dependent variables. Three tools selected for study include Rock drill (Dry type (Tool-1, Concrete breaker (Tool-2, Hand grinder (Tool-3. The impact of vibration exposure on health of operators is assessed by the help of survey. It is found that the human energy expenditure is more in the subjects having low grip strength whereas it is less in the subjects of more grip strength. The subjects having more grip strength show less change in touch sensation. The human energy expenditure of subjects of hand grinder is significantly less than the subjects of rock drill and concrete breaker. The presence of hand arm vibration Syndrome (HAVS in the subjects under heavy work, like rock drill and concrete breaker found very high.

  3. Effects of Machine Tool Configuration on Its Dynamics Based on Orthogonal Experiment Method

    Institute of Scientific and Technical Information of China (English)

    GAO Xiangsheng; ZHANG Yidu; ZHANG Hongwei; WU Qiong

    2012-01-01

    In order to analyze the influence of configuration parameters on dynamic characteristics of machine tools in the working space,the configuration parameters have been suggested based on the orthogonal experiment method.Dynamic analysis of a milling machine,which is newly designed for producing turbine blades,has been conducted by utilizing the modal synthesis method.The finite element model is verified and updated by experimental modal analysis (EMA) of the machine tool.The result gained by modal synthesis method is compared with whole-model finite element method (FEM) result as well.According to the orthogonal experiment method,four configuration parameters of machine tool are considered as four factors for dynamic characteristics.The influence of configuration parameters on the first three natural frequencies is obtained by range analysis.It is pointed out that configuration parameter is the most important factor affecting the fundamental frequency of machine tools,and configuration parameter has less effect on lower-order modes of the system than others.The combination of configuration parameters which makes the fundamental frequency reach the maximum value is provided.Through demonstration,the conclusion can be drawn that the influence of configuration parameters on the natural frequencies of machine tools can be analyzed explicitly by the orthogonal experiment method,which offers a new method for estimating the dynamic characteristics of machine tools.

  4. IDENTIFICATION AND MONITORING OF NOISE SOURCES OF CNC MACHINE TOOLS BY ACOUSTIC HOLOGRAPHY METHODS

    Directory of Open Access Journals (Sweden)

    Jerzy Józwik

    2016-06-01

    Full Text Available The paper presents the analysis of sound field emitted by selected CNC machine tools. The identification of noise sources and level was measured by acoustic holography for the 3-axis DMC 635eco machine tool and the 5-axis vertical machining centre DMU 65 monoBlock. The acoustic holography method allows precise identification and measurement of noise sources at different bandwidths of frequency. Detection of noise sources in tested objects allows diagnosis of their technical condition, as well as choice of effective means of noise reduction, which is highly significant from the perspective of minimising noise at the CNC machine operator workstation. Test results were presented as acoustic maps in various frequency ranges. Noise sources of the machine tool itself were identified, as well as the range of noise influence and the most frequent places of reflections and their span. The results of measurements were presented in figures and diagrams.

  5. Theoretical analysis of the conditions for increasing the accuracy of the axial hole machining multiple tip tools

    Directory of Open Access Journals (Sweden)

    Т. М. Брижан

    2015-03-01

    Full Text Available This paper deals with the development of a mathematical model for determining the value of the elastic displacement that occurs when reaming and deployment of holes. The lack of theoretical studies of the analytical representation of the cutting force limits the study of conditions to improve the accuracy of hole machining. A promising direction should be considered a theoretical approach, which allows to determine the magnitude of the elastic displacement occurring in the technological system when drilling and thus to estimate the error handling holes. A further development of this approach is a theoretical analysis of the magnitude of the elastic displacement that occurs when processing multiple tip tools axial holes (core drills and reamers. In this paper, based on the analytic representation of cutting forces in machining holes axial multiple tip tools have received a new theoretical solution of the nature of changes in the magnitude of the elastic displacement occurring in the technological system and determining error processing holes. Calculations revealed, that in the case of misalignment of the hole axis tool with four or more blades magnitude of the elastic displacement remains constant, regardless of the position of the blades. However, the torque varies cyclically, giving rise to a torsional oscillation process system. Proved, that with increasing amounts of the variable part of the tool blades torque decreases. It follows from this promising application of axial multiple tip tools (reamers, reamers with inclined blades, so as to avoid the time variation of torque and thus eliminate torsional vibrations in the technological system, that is essential for improving the accuracy of hole machining and surface finish class

  6. Remediation, General Education, and Technical Mathematics. Educational Resources for the Machine Tool Industry.

    Science.gov (United States)

    Texas State Technical Coll. System, Waco.

    This document contains descriptions of adult education courses in remediation, general education, and technical mathematics. They are part of a program developed by the Machine Tool Advanced Skills Technology Educational Resources (MASTER) program to help workers become competent in the skills needed to be productive workers in the machine tools…

  7. Wavelet Correlation Feature Scale Entropy and Fuzzy Support Vector Machine Approach for Aeroengine Whole-Body Vibration Fault Diagnosis

    Directory of Open Access Journals (Sweden)

    Cheng-Wei Fei

    2013-01-01

    Full Text Available In order to correctly analyze aeroengine whole-body vibration signals, Wavelet Correlation Feature Scale Entropy (WCFSE and Fuzzy Support Vector Machine (FSVM (WCFSE-FSVM method was proposed by fusing the advantages of the WCFSE method and the FSVM method. The wavelet coefficients were known to be located in high Signal-to-Noise Ratio (S/N or SNR scales and were obtained by the Wavelet Transform Correlation Filter Method (WTCFM. This method was applied to address the whole-body vibration signals. The WCFSE method was derived from the integration of the information entropy theory and WTCFM, and was applied to extract the WCFSE values of the vibration signals. Among the WCFSE values, the WFSE1 and WCFSE2 values on the scale 1 and 2 from the high band of vibration signal were believed to acceptably reflect the vibration feature and were selected to construct the eigenvectors of vibration signals as fault samples to establish the WCFSE-FSVM model. This model was applied to aeroengine whole-body vibration fault diagnosis. Through the diagnoses of four vibration fault modes and the comparison of the analysis results by four methods (SVM, FSVM, WESE-SVM, WCFSE-FSVM, it is shown that the WCFSE-FSVM method is characterized by higher learning ability, higher generalization ability and higher anti-noise ability than other methods in aeroengine whole-vibration fault analysis. Meanwhile, this present study provides a useful insight for the vibration fault diagnosis of complex machinery besides an aeroengine.

  8. Experimental study on bearing preload optimum of machine tool spindle

    Science.gov (United States)

    Xu, Tao; Xu, Guanghua; Zhang, Qin; Hua, Cheng; Zhang, Hu; Jiang, Kuosheng

    2012-05-01

    An experimental study is conducted to investigate the possibility and the effect of temperature rise and vibration level of bearing by adjusting axial preloads and radial loads in spindle bearing test rig. The shaft of the test rig is driven by a motorized high speed spindle at the range of 0~20000 rpm. The axial preloads and radial loads on bearings are controlled by using hydraulic pressure which can be adjusted automatically. Temperature rise and radial vibration of test bearings are measured by thermocouples and Polytec portable laser vibrometer PDV100. Experiment shows that the temperature rise of bearings is nonlinear varying with the increase of radial loads, but temperature rise almost increases linearly with the increase of axial preload and rotating speed. In this paper, an alternate axial preload is used for bearings. When the rotating speed passes through the critical speed of the shaft, axial preload of bearings will have a remarkable effect. The low preload could reduce bearing vibration and temperature rise for bearings as well. At the others speed, the high preload could improve the vibration performance of high speed spindle and the bearing temperature was lower than that of the constant pressure preload spindle.

  9. Error Modeling and Sensitivity Analysis of a Five-Axis Machine Tool

    Directory of Open Access Journals (Sweden)

    Wenjie Tian

    2014-01-01

    Full Text Available Geometric error modeling and its sensitivity analysis are carried out in this paper, which is helpful for precision design of machine tools. Screw theory and rigid body kinematics are used to establish the error model of an RRTTT-type five-axis machine tool, which enables the source errors affecting the compensable and uncompensable pose accuracy of the machine tool to be explicitly separated, thereby providing designers and/or field engineers with an informative guideline for the accuracy improvement by suitable measures, that is, component tolerancing in design, manufacturing, and assembly processes, and error compensation. The sensitivity analysis method is proposed, and the sensitivities of compensable and uncompensable pose accuracies are analyzed. The analysis results will be used for the precision design of the machine tool.

  10. DYNAMICS ANALYSIS OF SPECIAL STRUCTURE OF MILLING-HEAD MACHINE TOOL

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    The milling-bead machine tool is a sophisticated and high-quality machine tool of which the spindle system is made up of special multi-element structure. Two special mechanical configurations make the cutting performance of the machine tool decline. One is the milling head spindle supported on two sets of complex bearings. The mechanical dynamic rigidity of milling head structure is researched on designed digital prototype with finite element analysis(FEA) and modal synthesis analysis (MSA) for identifying the weak structures. The other is the ram structure hanging on milling head. The structure is researched to get dynamic performance on cutting at different ram extending positions. The analysis results on spindle and ram are used to improve the mechanical configurations and structure in design. The machine tool is built up with modified structure and gets better dynamic rigidity than it was before.

  11. Engineering Tools for Variable Stiffness Vibration Suppression and Isolation

    Science.gov (United States)

    2004-12-01

    2-12 MRFs magnetorheological �uids . . . . . . . . . . . . . . . . . . . . . 2-18 ERFs electrorheological �uids...Active control is a method of loading a vibrational path using force actuators that require external energy and information as inputs [8], [9...17], 2-3 [4]. Hence, semi-active control di¤ers from hybrid control in that hybrid control employs additional actuators to implement the active control

  12. THEORETICAL CLARIFICATIONS REGARDING THE CONCEPT OF WORKING CAPACITY OF WOOD-WORKING MACHINE-TOOLS

    Directory of Open Access Journals (Sweden)

    Gavril BUDĂU

    2014-09-01

    Full Text Available Due to persisting confusions between the concepts “labor productivity” and “working capacity” of a machine-tool, equipment or production line, the authors considered it necessary to define and explain these terms. Starting by defining the notions “working cycle” and “functioning cycle”, the paper details: the theoretical, technological and real working capacity and also the term “working time norm” for wood-working machine-tools.

  13. Towards a Tool for Computer Supported Configuring of Machine Systems

    DEFF Research Database (Denmark)

    Hansen, Claus Thorp

    1996-01-01

    An engineering designer designing a product determines not only the product's component structure, but also a set of different structures which carry product behaviour and performance and make the product suited for its life phases. Whereas the nature of the elements of a machine system is fairly...

  14. Winding machine and tools for the ISR Superconducting Quadrupole Prototype

    CERN Multimedia

    1975-01-01

    The picture shows the rotating and rocking winding machine with its "light" clamping system to keep the conductor turns in place during winding.At the back left one sees the conductor spool with its electromagnetic brake and the "heavy" clamping system used during curing. See also 7510217X, 7702690X.

  15. Atwood's Machine as a Tool to Introduce Variable Mass Systems

    Science.gov (United States)

    de Sousa, Celia A.

    2012-01-01

    This article discusses an instructional strategy which explores eventual similarities and/or analogies between familiar problems and more sophisticated systems. In this context, the Atwood's machine problem is used to introduce students to more complex problems involving ropes and chains. The methodology proposed helps students to develop the…

  16. A Comparative Study of Teacher Education Institutions and Machine Tool Manufacturers to Determine Course Content for a Machine Tool Maintenance Course in the Woodworking Area.

    Science.gov (United States)

    Polette, Douglas Lee

    To determine what type of maintenance training the prospective industrial arts teacher should receive in the woodworking area and how this information should be taught, a research instrument was constructed using information obtained from a review of relevant literature. Specific data on machine tool maintenance was gathered by the use of two…

  17. High accurate interpolation of NURBS tool path for CNC machine tools

    Science.gov (United States)

    Liu, Qiang; Liu, Huan; Yuan, Songmei

    2016-09-01

    Feedrate fluctuation caused by approximation errors of interpolation methods has great effects on machining quality in NURBS interpolation, but few methods can efficiently eliminate or reduce it to a satisfying level without sacrificing the computing efficiency at present. In order to solve this problem, a high accurate interpolation method for NURBS tool path is proposed. The proposed method can efficiently reduce the feedrate fluctuation by forming a quartic equation with respect to the curve parameter increment, which can be efficiently solved by analytic methods in real-time. Theoretically, the proposed method can totally eliminate the feedrate fluctuation for any 2nd degree NURBS curves and can interpolate 3rd degree NURBS curves with minimal feedrate fluctuation. Moreover, a smooth feedrate planning algorithm is also proposed to generate smooth tool motion with considering multiple constraints and scheduling errors by an efficient planning strategy. Experiments are conducted to verify the feasibility and applicability of the proposed method. This research presents a novel NURBS interpolation method with not only high accuracy but also satisfying computing efficiency.

  18. MODELING AND COMPENSATION TECHNIQUE FOR THE GEOMETRIC ERRORS OF FIVE-AXIS CNC MACHINE TOOLS

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    One of the important trends in precision machining is the development of real-time error compensation technique.The error compensation for multi-axis CNC machine tools is very difficult and attractive.The modeling for the geometric error of five-axis CNC machine tools based on multi-body systems is proposed.And the key technique of the compensation-identifying geometric error parameters-is developed.The simulation of cutting workpiece to verify the modeling based on the multi-body systems is also considered.

  19. The characteristics of machined surface controlled by multi tip arrayed tool and high speed spindle.

    Science.gov (United States)

    Kim, Yong Woo; Choi, Soo Chang; Park, Jeong Woo; Lee, Deug Woo

    2010-07-01

    In this study, we propose one of the ultra-precision machining methods that can be adapted brittle material as well as soft material by using multi arrayed diamond tips and high speed spindle. Conventional machining method is too hard to control surface roughness and surface texture against brittle material because particles of grinding tools are irregular size and material can be fragile. Therefore we were able to design tool paths and machine controlled pattern on surface by multi arrayed diamond tips which has uniform size made in MEMS fabrication and high speed spindle of which maximum speed is about 300,000 rpm. We defined several parameters that can have effect on machining surface. Those are multi array of diamond tips (n * n), speed of the air spindle, and feeding rate. Surface roughness and surface texture can be controlled by those parameters for micro machining.

  20. Development of a perpendicular vibration-induced electrical discharge machining process for fabrication of partially wavy inner structures

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Ju Chul; Park, Sang Hu; Min, June Kee; Ha, Man Yeong; Shin, Bo Sung [Pusan National University, Busan (Korea, Republic of); Cho, Jong Rae [Korea Maritime University, Busan (Korea, Republic of)

    2016-05-15

    Heat transfer enhancement is an important issue in energy systems. To improve the efficiency of a cooling channel used inside injection molds, turbine blades, and high-temperature devices, channels with various shapes, such as wavy, elliptical, and twisted, have been studied. A cooling channel with a partially wavy inner structure has shown outstanding cooling performance despite a small increase in friction factor. However, generating a partially wavy inner structure inside a channel through conventional machining processes is not easy. To address this problem, we developed a new process called Perpendicular vibration-induced electrical discharge machining (PV-EDM). A specific electrode and one- and random-directional vibrating devices controlled by a pneumatic load were designed for the PV-EDM process. Experimental results showed that local shaping on the inner wall of a channel is possible, which confirmed the possibility of application of this process to actual industrial problems.

  1. Control of oscillations in vibration machines: Start up and passage through resonance

    Science.gov (United States)

    Fradkov, A.; Gorlatov, D.; Tomchina, O.; Tomchin, D.

    2016-11-01

    Control of oscillations in mechanical systems in the start-up and passage through resonance modes is studied. In both cases, the control algorithm is based on the speed-gradient method with energy-based goal functions. It is shown that for Hamiltonian 1-degree of freedom (DOF) systems, it is generically possible to move the system from any initial state to any final state by means of a controlling force of arbitrarily small intensity. Controlled passage through resonance is studied for a 5-DOF vibration machine taking friction into account. It is shown by simulation that applying feedback control makes passage through lower resonance feasible with smaller control intensity compared with passage through resonance under constant control torque. The specific feature of this paper is consideration of the case when constant control torques do not allow the rotors even to start rotation. Applying feedback control allows rotors to overcome gravity and to start rotation. Another key novelty of this paper is comparison of the results obtained from the simulation with the experimental results obtained from the two-rotor laboratory mechatronic stand. It appears that most results are qualitatively the same, which confirms the adequacy of the model.

  2. Development of Prediction System for Environmental Burden for Machine Tool Operation

    Science.gov (United States)

    Narita, Hirohisa; Kawamura, Hiroshi; Norihisa, Takashi; Chen, Lian-Yi; Fujimoto, Hideo; Hasebe, Takao

    Recently, some activities for environmental protection have been attempted to reduce environmental burdens in many fields. The manufacturing field also requires such reduction. Hence, a prediction system for environmental burden for machining operation is proposed based on the Life Cycle Assessment (LCA) policy for the future manufacturing system in this research. This system enables the calculation of environmental burden (equivalent CO2 emission) due to the electric consumption of machine tool components, cutting tool status, coolant quantity, lubricant oil quantity and metal chip quantity, and provides accurate information of environmental burden of the machining process by considering some activities related to machine tool operation. In this paper, the development of the prediction system is described. As a case study, two Numerical Control (NC) programs that manufacture a simple shape are evaluated to show the feasibility of the proposed system.

  3. Machine-tool control system for turning nonaxisymmetric surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Douglass, S.S.; Green, W.L.

    1979-09-01

    A development program has been initiated to allow on-axis turning of nonaxisymmetric surfaces. A short-travel high-speed slide is mounted on a precision, numerically controlled, two-axis turning machine. The motion of the auxiliary slide is synchronized with the spindle and the two remaining slides. The report defines the workpiece geometry and requirements, calculations for the slide motion, techniques for real-time command generation, and planned equipment set.

  4. Machine Learning Tools for Geomorphic Mapping of Planetary Surfaces

    OpenAIRE

    Stepinski, Tomasz F.; Vilalta, Ricardo

    2010-01-01

    Geomorphic auto-mapping of planetary surfaces is a challenging problem. Here we have described how machine learning techniques, such as clustering or classification, can be utilized to automate the process of geomorphic mapping for exploratory and exploitation purposes. Relatively coarse resolution of planetary topographic data limits the number of features that can be used in the learning process and makes planetary auto-mapping more challenging than terrestrial auto-mapping. With this cavea...

  5. Modular reconfigurable machine tools: design, control and evaluation

    CSIR Research Space (South Africa)

    Padayachee, J

    2009-11-01

    Full Text Available -process capacity scaling. Scalable production capacity and adjustable system functionality are the key objectives of reconfigurable manufacturing. Index terms: Reconfigurable Manufacturing Systems, Modular Reconfigurable Machines, Open Architecture Control...] identify the fixed mechanical architectures and proprietary control systems found in CNC and DMT equipment as the specific drawback in effectively implementing these classes of equipment in RMS. Koren et al.[3] proposed the development of reconfigurable...

  6. Online machining error estimation method of numerical control gear grinding machine tool based on data analysis of internal sensors

    Science.gov (United States)

    Zhao, Fei; Zhang, Chi; Yang, Guilin; Chen, Chinyin

    2016-12-01

    This paper presents an online estimation method of cutting error by analyzing of internal sensor readings. The internal sensors of numerical control (NC) machine tool are selected to avoid installation problem. The estimation mathematic model of cutting error was proposed to compute the relative position of cutting point and tool center point (TCP) from internal sensor readings based on cutting theory of gear. In order to verify the effectiveness of the proposed model, it was simulated and experimented in gear generating grinding process. The cutting error of gear was estimated and the factors which induce cutting error were analyzed. The simulation and experiments verify that the proposed approach is an efficient way to estimate the cutting error of work-piece during machining process.

  7. On-line Tool Wear Classification in Unmanned-machining Environments

    Institute of Scientific and Technical Information of China (English)

    A; D; Hope; G; A; King

    2002-01-01

    One of the most important features of the modern ma ch ining system in an "unmanned" factory is to change tools that have been subjec ted to wear and damage. An integrated tool condition monitoring system composed of multi-sensors, signal processing devices and intelligent decision making pla ns is a necessary requirement for automatic manufacturing processes. An intellig ent tool wear monitoring system will be introduced in this paper. The system is equipped with power consumption, vibration, AE and cutt...

  8. Multi-component machine monitoring and fault diagnosis using blind source separation and advanced vibration analysis

    Science.gov (United States)

    Mahvash Mohammadi, Ali

    synthetic and real data. If a standard evaluation metric is available, more rigorous evaluation of blind source separation techniques can be achieved. The foremost existing solution to blind source separation is Independent Component Analysis (ICA). In ICA it is assumed that the source signals are statistically independent from one another and can therefore be recovered by formulating the independence. There are, however, two dominant ambiguities and indeterminacies associated with ICA results. One ambiguity is that the original index or permutation of the recovered source signals is unknown. The other ambiguity is that the actual scale of the source signals cannot be determined. ICA can be applied in both time and frequency domains. In this dissertation, a new technique is proposed based mainly on the mechanical attributes of the system rather than unrealistic mathematical or statistical assumptions. This technique is developed based on the presumption that the mixing mechanism for neighboring frequency bins varies only slightly from one bin to another. Therefore, by numerically tying and relating the mixing matrices of contiguous frequency bins, local permutation and scale indeterminacy problems are resolved. This method is studied experimentally using laboratory data and the results are also compared with the evaluation metric presented in the previous study. Accordance between the results confirmed the efficacy of the proposed method. In the second approach, the effectiveness of cyclic spectral analysis is assessed for detecting bearing faults in complex machinery. Bearing faults are known to produce vibration with recurring impulsiveness in the energy which is referred to as cyclostationarity. Cyclic spectral analysis is a powerful tool to measure the cyclostationarity of a signal in different frequency ranges. For this tool to be effective in applications related to complex machinery, two requirements are identified. One requirement is that the tool must be capable of

  9. Comparison Between Cemented Carbide and PCD Tools on Machinability of a High Silicon Aluminum Alloy

    Science.gov (United States)

    Soares, R. B.; de Jesus, A. M. P.; Neto, R. J. L.; Chirita, B.; Rosa, P. A. R.; Reis, A.

    2017-08-01

    The high content of silicon of aluminum casting alloys challenges the tool life of conventional cemented carbide inserts, and polycrystalline diamond (PCD) tools appear as an interesting material to machine these alloys because they improve substantially the durability of cutting tools and consequently the productivity of machining. However, the surface roughness, cutting forces and chip morphology are equally important factors in machining evaluation. Therefore, an experimental study is performed aiming at comparing the performance of cemented carbide and PCD tools taking into account cutting forces, surface roughness and chip morphology, under dry longitudinal turning, performed for the AlSi9Cu3 alloy produced by permanent mold casting process. Different chip breaker geometries were also considered, and their influence on the referred parameters was also investigated. Analysis of variance was employed to study the different contributions of inserts, cutting speed, feed rate, depth of cut and their interactions in machinability performance. The results show low cutting forces and better results for surface roughness for uncoated cemented carbide tools, with simpler chip breakers and flat rake face PCD tool, but an efficient chip control was obtained for inserts with small grooves with high cutting forces and power consumption. Nevertheless, the feed rate and depth of cut have the highest influence on the machinability performance of the alloy under investigation.

  10. A chord error conforming tool path B-spline fitting method for NC machining based on energy minimization and LSPIA

    Directory of Open Access Journals (Sweden)

    Shanshan He

    2015-10-01

    Full Text Available Piecewise linear (G01-based tool paths generated by CAM systems lack G1 and G2 continuity. The discontinuity causes vibration and unnecessary hesitation during machining. To ensure efficient high-speed machining, a method to improve the continuity of the tool paths is required, such as B-spline fitting that approximates G01 paths with B-spline curves. Conventional B-spline fitting approaches cannot be directly used for tool path B-spline fitting, because they have shortages such as numerical instability, lack of chord error constraint, and lack of assurance of a usable result. Progressive and Iterative Approximation for Least Squares (LSPIA is an efficient method for data fitting that solves the numerical instability problem. However, it does not consider chord errors and needs more work to ensure ironclad results for commercial applications. In this paper, we use LSPIA method incorporating Energy term (ELSPIA to avoid the numerical instability, and lower chord errors by using stretching energy term. We implement several algorithm improvements, including (1 an improved technique for initial control point determination over Dominant Point Method, (2 an algorithm that updates foot point parameters as needed, (3 analysis of the degrees of freedom of control points to insert new control points only when needed, (4 chord error refinement using a similar ELSPIA method with the above enhancements. The proposed approach can generate a shape-preserving B-spline curve. Experiments with data analysis and machining tests are presented for verification of quality and efficiency. Comparisons with other known solutions are included to evaluate the worthiness of the proposed solution.

  11. CUTTING TEMPERATURE OF CBN TOOLS WHEN MACHINING STEEL OF MEDIUM HARDNESS

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The cutting temperature of CBN tools when machining hardened steel was investigated at different cutting regime and cutting tool geometry. An unusual phenomenon that the depth of cut influenced the temperature more significantly than the feed rate was analysed via partial differentiation. A chamfered cutting edge generally raised the cutting temperature and the significance of the temperature increase was associated with the cutting speed.

  12. Web-Based Machine Translation as a Tool for Promoting Electronic Literacy and Language Awareness

    Science.gov (United States)

    Williams, Lawrence

    2006-01-01

    This article addresses a pervasive problem of concern to teachers of many foreign languages: the use of Web-Based Machine Translation (WBMT) by students who do not understand the complexities of this relatively new tool. Although networked technologies have greatly increased access to many language and communication tools, WBMT is still…

  13. Possibilities of Application of High Pressure Jet Assisted Machining in Hard Turning with Carbide Tools

    Directory of Open Access Journals (Sweden)

    G. Globočki Lakić

    2017-06-01

    Full Text Available High Pressure Jet Assisted Machining (HPJAM in turning is a hybrid machining method in which a high pressure jet of cooling and lubrication fluid, under high pressure (50 MPa, leads to the zone between the cutting tool edge and workpiece. An experimental study was performed to investigate the capabilities of conventional and high pressure cooling (HPC in the turning of hard-to-machine materials: hard-chromed and surface hardened steel Ck45 (58 HRc and hardened bearing steel 100Cr6 (62 HRc. Machining experiments were performed using coated carbide tools and highly cutting speed. Experimental measurements were performed for different input process parameters. The cooling capabilities are compared by monitoring of tool wear, tool life, cooling efficiency, and surface roughness. Connection between the tool wear and surface roughness is established. Experimental research show that the hard turning with carbide cutting tools and HP supply CLF provides numerous advantages from the techno-economic aspect: greater productivity, reduce of temperature in the cutting zone, improved control chip formation, extended tool life, low intensity of tool wear, surface roughness in acceptable limits, significant reduce of production costs related to the CLF.

  14. Integrating Oil Debris and Vibration Measurements for Intelligent Machine Health Monitoring. Degree awarded by Toledo Univ., May 2002

    Science.gov (United States)

    Dempsey, Paula J.

    2003-01-01

    A diagnostic tool for detecting damage to gears was developed. Two different measurement technologies, oil debris analysis and vibration were integrated into a health monitoring system for detecting surface fatigue pitting damage on gears. This integrated system showed improved detection and decision-making capabilities as compared to using individual measurement technologies. This diagnostic tool was developed and evaluated experimentally by collecting vibration and oil debris data from fatigue tests performed in the NASA Glenn Spur Gear Fatigue Rig. An oil debris sensor and the two vibration algorithms were adapted as the diagnostic tools. An inductance type oil debris sensor was selected for the oil analysis measurement technology. Gear damage data for this type of sensor was limited to data collected in the NASA Glenn test rigs. For this reason, this analysis included development of a parameter for detecting gear pitting damage using this type of sensor. The vibration data was used to calculate two previously available gear vibration diagnostic algorithms. The two vibration algorithms were selected based on their maturity and published success in detecting damage to gears. Oil debris and vibration features were then developed using fuzzy logic analysis techniques, then input into a multi sensor data fusion process. Results show combining the vibration and oil debris measurement technologies improves the detection of pitting damage on spur gears. As a result of this research, this new diagnostic tool has significantly improved detection of gear damage in the NASA Glenn Spur Gear Fatigue Rigs. This research also resulted in several other findings that will improve the development of future health monitoring systems. Oil debris analysis was found to be more reliable than vibration analysis for detecting pitting fatigue failure of gears and is capable of indicating damage progression. Also, some vibration algorithms are as sensitive to operational effects as they

  15. Data mining practical machine learning tools and techniques

    CERN Document Server

    Witten, Ian H

    2005-01-01

    As with any burgeoning technology that enjoys commercial attention, the use of data mining is surrounded by a great deal of hype. Exaggerated reports tell of secrets that can be uncovered by setting algorithms loose on oceans of data. But there is no magic in machine learning, no hidden power, no alchemy. Instead there is an identifiable body of practical techniques that can extract useful information from raw data. This book describes these techniques and shows how they work. The book is a major revision of the first edition that appeared in 1999. While the basic core remains the same

  16. Characterizing EMG data using machine-learning tools.

    Science.gov (United States)

    Yousefi, Jamileh; Hamilton-Wright, Andrew

    2014-08-01

    Effective electromyographic (EMG) signal characterization is critical in the diagnosis of neuromuscular disorders. Machine-learning based pattern classification algorithms are commonly used to produce such characterizations. Several classifiers have been investigated to develop accurate and computationally efficient strategies for EMG signal characterization. This paper provides a critical review of some of the classification methodologies used in EMG characterization, and presents the state-of-the-art accomplishments in this field, emphasizing neuromuscular pathology. The techniques studied are grouped by their methodology, and a summary of the salient findings associated with each method is presented.

  17. Correlation between vibration amplitude and tool wear in turning: Numerical and experimental analysis

    Directory of Open Access Journals (Sweden)

    Balla Srinivasa Prasad

    2017-02-01

    Full Text Available In this paper, a correlation between vibration amplitude and tool wear when in dry turning of AISI 4140 steel using uncoated carbide insert DNMA 432 is analyzed via experiments and finite element simulations. 3D Finite element simulations results are utilized to predict the evolution of cutting forces, vibration displacement amplitudes and tool wear in vibration induced turning. In the present paper, the primary concern is to find the relative vibration and tool wear with the variation of process parameters. These changes lead to accelerated tool wear and even breakage. The cutting forces in the feed direction are also predicted and compared with the experimental trends. A laser Doppler vibrometer is used to detect vibration amplitudes and the usage of Kistler 9272 dynamometer for recording the cutting forces during the cutting process is well demonstrated. A sincere effort is put to investigate the influence of spindle speed, feed rate, depth of cut on vibration amplitude and tool flank wear at different levels of workpiece hardness. Empirical models have been developed using second order polynomial equations for correlating the interaction and higher order influences of various process parameters. Analysis of variance (ANOVA is carried out to identify the significant factors that are affecting the vibration amplitude and tool flank wear. Response surface methodology (RSM is implemented to investigate the progression of flank wear and displacement amplitude based on experimental data. While measuring the displacement amplitude, R-square values for experimental and numerical methods are 98.6 and 97.8. Based on the R-square values of ANOVA it is found that the numerical values show good agreement with the experimental values and are helpful in estimating displacement amplitude. In the case of predicting the tool wear, R-square values were found to be 97.69 and 96.08, respectively for numerical and experimental measures while determining the tool

  18. Universal geometric error modeling of the CNC machine tools based on the screw theory

    Science.gov (United States)

    Tian, Wenjie; He, Baiyan; Huang, Tian

    2011-05-01

    The methods to improve the precision of the CNC (Computerized Numerical Control) machine tools can be classified into two categories: error prevention and error compensation. Error prevention is to improve the precision via high accuracy in manufacturing and assembly. Error compensation is to analyze the source errors that affect on the machining error, to establish the error model and to reach the ideal position and orientation by modifying the trajectory in real time. Error modeling is the key to compensation, so the error modeling method is of great significance. Many researchers have focused on this topic, and proposed many methods, but we can hardly describe the 6-dimensional configuration error of the machine tools. In this paper, the universal geometric error model of CNC machine tools is obtained utilizing screw theory. The 6-dimensional error vector is expressed with a twist, and the error vector transforms between different frames with the adjoint transformation matrix. This model can describe the overall position and orientation errors of the tool relative to the workpiece entirely. It provides the mathematic model for compensation, and also provides a guideline in the manufacture, assembly and precision synthesis of the machine tools.

  19. Bayesian networks modeling for thermal error of numerical control machine tools

    Institute of Scientific and Technical Information of China (English)

    Xin-hua YAO; Jian-zhong FU; Zi-chen CHEN

    2008-01-01

    The interaction between the heat source location,its intensity,thermal expansion coefficient,the machine system configuration and the running environment creates complex thermal behavior of a machine tool,and also makes thermal error prediction difficult.To address this issue,a novel prediction method for machine tool thermal error based on Bayesian networks (BNs) was presented.The method described causal relationships of factors inducing thermal deformation by graph theory and estimated the thermal error by Bayesian statistical techniques.Due to the effective combination of domain knowledge and sampled data,the BN method could adapt to the change of running state of machine,and obtain satisfactory prediction accuracy.Ex-periments on spindle thermal deformation were conducted to evaluate the modeling performance.Experimental results indicate that the BN method performs far better than the least squares(LS)analysis in terms of modeling estimation accuracy.

  20. Machining Duplex Stainless Steel: Comparative Study Regarding End Mill Coated Tools

    Directory of Open Access Journals (Sweden)

    Ronny M. Gouveia

    2016-10-01

    Full Text Available The difficulties in the machining of duplex stainless steel are well known. However, research on this matter is rather limited. Suppliers offer quite different cutting tools for the same raw material, with end mills of two, three or even four knives and a huge number of distinct coatings, some of them under commercial brands, making it difficult to assess the advantages they offer. Furthermore, there is a remarkable difference among the several types of duplex stainless steel available nowadays on the market. The present work intends to assess the machining performance of different tools, analyzing the behavior and wear mechanisms with two different cutting lengths, keeping constant the machining trajectory. Some other parameters were also kept constant, such as cutting speed, depth of cut and cutting width, as well as feed per tooth. The machining process was carried out under lubricated conditions, using an emulsion of 5% oil in water. Tools provided with a different number of teeth and surface coatings were tested, analyzing the wear behavior of each cutting length using scanning electron microscopy, trying to identify wear performance and how each coating contributes to increased tool life. The surfaces produced were also analyzed by means of profilometry measurements, correlating tool wear and part surface roughness. This comparative study allows determining the advantages of different tools relative to others, based on coatings and tool geometry.

  1. SIMULATION SYSTEM FOR FIVE-AXIS NC MACHINING USING GENERAL CUTTING TOOL

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A simulation system for five-axis NC machining using general cutting tools is presented. This system differs from other simulation system in that it not only focuses on the geometric simulation but also focuses on the collision detection which is usually not included in NC machining simulation. Besides all of these, estimating cutting forces is also discussed. In order to obtain high efficiency, all algorithms use swept volume modeling technique, so the simulation system is compact and can be performed efficiently.

  2. Experimental Investigation on the Material Removal of the Ultrasonic Vibration Assisted Abrasive Water Jet Machining Ceramics

    Directory of Open Access Journals (Sweden)

    Tao Wang

    2017-01-01

    Full Text Available The ultrasonic vibration activated in the abrasive water jet nozzle is used to enhance the capability of the abrasive water jet machinery. The experiment devices of the ultrasonic vibration assisted abrasive water jet are established; they are composed of the ultrasonic vibration producing device, the abrasive supplying device, the abrasive water jet nozzle, the water jet intensifier pump, and so on. And the effect of process parameters such as the vibration amplitude, the system working pressure, the stand-off, and the abrasive diameter on the ceramics material removal is studied. The experimental result indicates that the depth and the volume removal are increased when the ultrasonic vibration is added on abrasive water jet. With the increase of vibration amplitude, the depth and the volume of material removal are also increased. The other parameters of the ultrasonic vibration assisted abrasive water jet also have an important role in the improvement of ceramic material erosion efficiency.

  3. Multi-Parameter Analysis of Surface Finish in Electro-Discharge Machining of Tool Steels

    Directory of Open Access Journals (Sweden)

    Cornelia Victoria Anghel

    2006-10-01

    Full Text Available The paper presents a multi- parameter analysis of surface finish imparted to tool-steel plates by electro-discharge machining (EDM is presented. The interrelationship between surface texture parameters and process parameters is emphasized. An increased number of parameters is studied including amplitude, spacing, hybrid and fractal parameters,, as well. The correlation of these parameters with the machining conditions is investigated. Observed characteristics become more pronounced, when intensifying machining conditions. Close correlation exists between certain surface finish parameters and EDM input variables and single and multiple statistical regression models are developed.

  4. The use of machine learning and nonlinear statistical tools for ADME prediction.

    Science.gov (United States)

    Sakiyama, Yojiro

    2009-02-01

    Absorption, distribution, metabolism and excretion (ADME)-related failure of drug candidates is a major issue for the pharmaceutical industry today. Prediction of ADME by in silico tools has now become an inevitable paradigm to reduce cost and enhance efficiency in pharmaceutical research. Recently, machine learning as well as nonlinear statistical tools has been widely applied to predict routine ADME end points. To achieve accurate and reliable predictions, it would be a prerequisite to understand the concepts, mechanisms and limitations of these tools. Here, we have devised a small synthetic nonlinear data set to help understand the mechanism of machine learning by 2D-visualisation. We applied six new machine learning methods to four different data sets. The methods include Naive Bayes classifier, classification and regression tree, random forest, Gaussian process, support vector machine and k nearest neighbour. The results demonstrated that ensemble learning and kernel machine displayed greater accuracy of prediction than classical methods irrespective of the data set size. The importance of interaction with the engineering field is also addressed. The results described here provide insights into the mechanism of machine learning, which will enable appropriate usage in the future.

  5. Optimization of Operation Sequence in CNC Machine Tools Using Genetic Algorithm

    Science.gov (United States)

    Abu Qudeiri, Jaber; Yamamoto, Hidehiko; Ramli, Rizauddin

    The productivity of machine tools is significantly improved by using microcomputer based CAD/CAM systems for NC program generation. Currently, many commercial CAD/CAM packages that provide automatic NC programming have been developed and applied to various cutting processes. Many cutting processes machined by CNC machine tools. In this paper, we attempt to find an efficient solution approach to determine the best sequence of operations for a set of operations that located in asymmetrical locations and different levels. In order to find the best sequence of operations that achieves the shortest cutting tool travel path (CTTP), genetic algorithm is introduced. After the sequence is optimized, the G-codes that use to code for the travel time is created. CTTP can be formulated as a special case of the traveling salesman problem (TSP). The incorporation of genetic algorithm and TSP can be included in the commercial CAD/CAM packages to optimize the CTTP during automatic generation of NC programs.

  6. Research on assembly reliability control technology for computer numerical control machine tools

    Directory of Open Access Journals (Sweden)

    Yan Ran

    2017-01-01

    Full Text Available Nowadays, although more and more companies focus on improving the quality of computer numerical control machine tools, its reliability control still remains as an unsolved problem. Since assembly reliability control is very important in product reliability assurance in China, a new key assembly processes extraction method based on the integration of quality function deployment; failure mode, effects, and criticality analysis; and fuzzy theory for computer numerical control machine tools is proposed. Firstly, assembly faults and assembly reliability control flow of computer numerical control machine tools are studied. Secondly, quality function deployment; failure mode, effects, and criticality analysis; and fuzzy theory are integrated to build a scientific extraction model, by which the key assembly processes meeting both customer functional demands and failure data distribution can be extracted, also an example is given to illustrate the correctness and effectiveness of the method. Finally, the assembly reliability monitoring system is established based on key assembly processes to realize and simplify this method.

  7. A Two-stage Tuning Method of Servo Parameters for Feed Drives in Machine Tools

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Based on the evaluation of dynamic performance for feed drives in machine tools, this paper presents a two-stage tuning method of servo parameters. In the first stage, the evaluation of dynamic performance, parameter tuning and optimization on a mechatronic integrated system simulation platform of feed drives are performed. As a result, a servo parameter combination is acquired. In the second stage, the servo parameter combination from the first stage is set and tuned further in a real machine tool whose dynamic performance is measured and evaluated using the cross grid encoder developed by Heidenhain GmbH. A case study shows that this method simplifies the test process effectively and results in a good dynamic performance in a real machine tool.

  8. A Method to Optimize Geometric Errors of Machine Tool based on SNR Quality Loss Function and Correlation Analysis

    Directory of Open Access Journals (Sweden)

    Cai Ligang

    2017-01-01

    Full Text Available Instead improving the accuracy of machine tool by increasing the precision of key components level blindly in the production process, the method of combination of SNR quality loss function and machine tool geometric error correlation analysis to optimize five-axis machine tool geometric errors will be adopted. Firstly, the homogeneous transformation matrix method will be used to build five-axis machine tool geometric error modeling. Secondly, the SNR quality loss function will be used for cost modeling. And then, machine tool accuracy optimal objective function will be established based on the correlation analysis. Finally, ISIGHT combined with MATLAB will be applied to optimize each error. The results show that this method is reasonable and appropriate to relax the range of tolerance values, so as to reduce the manufacturing cost of machine tools.

  9. 基于免疫反馈算法的缝纫设备振动控制研究%Research on Sewing Machine Vibration Control Based on Immune Feedback Algorithm

    Institute of Scientific and Technical Information of China (English)

    林君焕; 陈月芬; 张国庆

    2012-01-01

    The vibration is harmful to sewing performance. In order to decrease the harm, a sewing machine vibration active control system is developed, in which the giant magnetostrictive actuator is adopted, satisfying the design requirements on control precise and frequency response. The giant magnetostrictive actuator and sewing machine is modeled, on the base of the research on giant magnetostrictive actuator' s principle and sewing machine vibration character. An immune feedback controller based on artificial immune is designed, and the simulation on MATLAB with the tool of Simulink and test on the industrial sewing machine is demonstrated, the results prove that the system can effectively suppress the vibration of sewing machine from motor in sewing.%为降低缝纫设备缝纫时产生的振动对缝纫性能的影响,开发了一种缝纫设备振动主动控制系统.该系统中的执行机构采用超磁致执行器,能满足振动控制精度和频响的要求.在完成系统的总体设计后,研究了超磁致伸缩执行器工作原理以及缝纫设备机身的振动特性,并分别对他们进行建模.设计了一种基于人工免疫原理的免疫反馈控制器,采用MATLAB环境中的Simulink工具对控制系统进行建模仿真,并在工业缝纫机上进行了现场实验测试,结果证明该系统能很好地抑制缝纫时引起的机身振动.

  10. INL Review of Fueling Machine Inspection Tool Development Proposal

    Energy Technology Data Exchange (ETDEWEB)

    Griffith, George [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    A review of a technical proposal for James Fischer Nuclear. The document describes an inspection tool to examine the graphite moderator in an AGR reactor. The system is an optical system to look at the graphite blocks for cracks. INL reviews the document for technical value.

  11. Process planning optimization on turning machine tool using a hybrid genetic algorithm with local search approach

    Directory of Open Access Journals (Sweden)

    Yuliang Su

    2015-04-01

    Full Text Available A turning machine tool is a kind of new type of machine tool that is equipped with more than one spindle and turret. The distinctive simultaneous and parallel processing abilities of turning machine tool increase the complexity of process planning. The operations would not only be sequenced and satisfy precedence constraints, but also should be scheduled with multiple objectives such as minimizing machining cost, maximizing utilization of turning machine tool, and so on. To solve this problem, a hybrid genetic algorithm was proposed to generate optimal process plans based on a mixed 0-1 integer programming model. An operation precedence graph is used to represent precedence constraints and help generate a feasible initial population of hybrid genetic algorithm. Encoding strategy based on data structure was developed to represent process plans digitally in order to form the solution space. In addition, a local search approach for optimizing the assignments of available turrets would be added to incorporate scheduling with process planning. A real-world case is used to prove that the proposed approach could avoid infeasible solutions and effectively generate a global optimal process plan.

  12. Hardening Effect on Machined Surface for Precise Hard Cutting Process with Consideration of Tool Wear

    Institute of Scientific and Technical Information of China (English)

    YANG Yongheng

    2014-01-01

    During hard cutting process there is severe thermodynamic coupling effect between cutting tool and workpiece, which causes quenching effect on finished surfaces under certain conditions. However, material phase transformation mechanism of heat treatment in cutting process is different from the one in traditional process, which leads to changes of the formation mechanism of damaged layer on machined workpiece surface. This paper researches on the generation mechanism of damaged layer on machined surface in the process of PCBN tool hard cutting hardened steel Cr12MoV. Rules of temperature change on machined surface and subsurface are got by means of finite element simulation. In phase transformation temperature experiments rapid transformation instrument is employed, and the effect of quenching under cutting conditions on generation of damaged layer is revealed. Based on that, the phase transformation points of temperature under cutting conditions are determined. By experiment, the effects of cutting speed and tool wear on white layer thickness in damaged layer are revealed. The temperature distribution law of third deformation zone is got by establishing the numerical prediction model, and thickness of white layer in damaged layer is predicted, taking the tool wear effect into consideration. The experimental results show that the model prediction is accurate, and the establishment of prediction model provides a reference for wise selection of parameters in precise hard cutting process. For the machining process with high demanding on surface integrity, the generation of damaged layer on machined surface can be controlled precisely by using the prediction model.

  13. Of Genes and Machines: application of a combination of machine learning tools to astronomy datasets

    CERN Document Server

    Heinis, S; Gezari, S; Burgett, W S; Chambers, K C; Draper, P W; Flewelling, H; Kaiser, N; Magnier, E A; Metcalfe, N; Waters, C

    2016-01-01

    We apply a combination of a Genetic Algorithms (GA) and Support Vector Machines (SVM) machine learning algorithm to solve two important problems faced by the astronomical community: star/galaxy separation, and photometric redshift estimation of galaxies in survey catalogs. We use the GA to select the relevant features in the first step, followed by optimization of SVM parameters in the second step to obtain an optimal set of parameters to classify or regress, in process of which we avoid over-fitting. We apply our method to star/galaxy separation in Pan-STARRS1 data. We show that our method correctly classifies 98% of objects down to i_P1= 24.5, with a completeness (or true positive rate) of 99% for galaxies, and 88% for stars. By combining colors with morphology, our star/classification method yields better results than the new SExtractor classifier spread_model in particular at the faint end (i_P1>22). We also use our method to derive photometric redshifts for galaxies in the COSMOS bright multi-wavelength ...

  14. A novel triple-actuating mechanism of an active air mount for vibration control of precision manufacturing machines: experimental work

    Science.gov (United States)

    Kim, Hyung-Tae; Kim, Cheol-Ho; Choi, Seung-Bok; Moon, Seok-Jun; Song, Won-Gil

    2014-07-01

    With the goal of vibration control and isolation in a clean room, we propose a new type of air mount which consists of pneumatic, electromagnetic (EM), and magnetorheological (MR) actuators. The air mount is installed below a semiconductor manufacturing machine to reduce the adverse effects caused by unwanted vibration. The proposed mechanism integrates the forces in a parallel connection of the three actuators. The MR part is designed to operate in an air spring in which the EM part is installed. The control logic is developed with a classical method and a switching mode to avoid operational mismatch among the forces developed. Based on extended microprocessors, a portable, embedded controller is installed to execute both nonlinear logic and digital communication with the peripherals. The pneumatic forces constantly support the heavy weight of an upper structure and maintain the level of the air mount. The MR damper handles the transient response, while the EM controller reduces the resonance response, which is switched mutually with a threshold. Vibration is detected by laser displacement sensors which have submicron resolution. The impact test results of three tons load weight demonstrate practical feasibility by showing that the proposed triple-actuating mechanism can reduce the transient response as well as the resonance in the air mount, resulting in accurate motion of the semiconductor manufacturing machine.

  15. Analysis on China's machine tool import in 2001%2001年中国机床进口分析

    Institute of Scientific and Technical Information of China (English)

    DING Xuesheng

    2002-01-01

    @@ In 2001, China's import of machine tool and tool products has continuously kept in a great increasing. The imported total value is as much as US 3359 million,22.7% increased than that in same period in 2000. Among them, the import of metalworking machines is 2406 million, increased by 27.27% (for detail see "Statistics of China's Machine Tool Foreign Trade in 2000 and 2001",WMEM, No. 2 2002 and 2001).

  16. A Scheduling System Based on Rules of the Machine Tools in FMS

    Institute of Scientific and Technical Information of China (English)

    LI De-xin; ZHAO Hua-qun; JIA Jie; LU Yan-jun

    2003-01-01

    In this paper, a model of the scheduling of machine tools in the flexible manufacturing line is presented by intensive analysis and research of the mathematical method of traditional scheduling. The various factors correlative with machine tools in the flexible manufacturing line are fully considered in this system. Aiming at this model, an intelligent decision system based on rules and simulation technolo-gy integration is constructed by using the OOP ( Object-Orented Programming) method, and the simula-tion experiment analysis is carried out. It is shown from the results that the model is better in practice.

  17. FLOW STRESS MODEL FOR HARD MACHINING OF AISI H13 WORK TOOL STEEL

    Institute of Scientific and Technical Information of China (English)

    H. Yan; J. Hua; R. Shivpuri

    2005-01-01

    An approach is presented to characterize the stress response of workpiece in hard machining,accounted for the effect of the initial workpiece hardness, temperature, strain and strain rate on flow stress. AISI H13 work tool steel was chosen to verify this methodology. The proposed flow stress model demonstrates a good agreement with data collected from published experiments.Therefore, the proposed model can be used to predict the corresponding flow stress-strain response of AISI H13 work tool steel with variation of the initial workpiece hardness in hard machining.

  18. Kinematic simulation of a parallel NC machine tool in the manufacturing process

    Institute of Scientific and Technical Information of China (English)

    ZHANG Jian-min; FAN Yu; JIA Dong-yun; ZOU Qiu-ling; WU Ying

    2006-01-01

    Aimed at enhancing the research status of parallel machine tools,this paper introduces the structure of a 6-SPS parallel machine tool and explains the application significance of the kinematic simulation of the manufacturing process.The simulation software was developed in Microsoft Visual C++6.0 using OpenGL API functions.The data flows are presented.Finally, a simulation application of odd leaf hyperboloid is performed before the manufacturing process; the kinematic simulation demonstrates the rationale of trace planning and the feasibility of manufacturing instruction.

  19. An Investigation into Error Source Identification of Machine Tools Based on Time-Frequency Feature Extraction

    Directory of Open Access Journals (Sweden)

    Dongju Chen

    2016-01-01

    Full Text Available This paper presents a new identification method to identify the main errors of the machine tool in time-frequency domain. The low- and high-frequency signals of the workpiece surface are decomposed based on the Daubechies wavelet transform. With power spectral density analysis, the main features of the high-frequency signal corresponding to the imbalance of the spindle system are extracted from the surface topography of the workpiece in the frequency domain. With the cross-correlation analysis method, the relationship between the guideway error of the machine tool and the low-frequency signal of the surface topography is calculated in the time domain.

  20. Program Suite for Conceptual Designing of Parallel Mechanism-Based Robots and Machine Tools

    Directory of Open Access Journals (Sweden)

    Slobodan Tabaković

    2013-06-01

    This paper describes the categorization of criteria for the conceptual design of parallel mechanism‐based robots or machine tools, resulting from workspace analysis as well as the procedure of their defining. Furthermore, it also presents the designing methodology that was implemented into the program for the creation of a robot or machine tool space model and the optimization of the resulting solution. For verification of the criteria and the programme suite, three common (conceptually different mechanisms with a similar mechanical structure and kinematic characteristics were used.

  1. An Universal Modeling Method for Enhancing the Volumetric Accuracy of CNC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Volumetric error modeling method is an important te ch nique for enhancement the accuracy of CNC machine tools by error compensation. I n the research field, the main question is how to find an universal kinematics m odeling method for different kinds of NC machine tools. Multi-body system theor y is always used to solve the dynamics problem of complex physical system. But t ill now, the error factors that always exist in practice system is still not con sidered. In this paper, the accuracy kinematics of MB...

  2. Research on virtual dynamic optimization design for NC machine tools

    Institute of Scientific and Technical Information of China (English)

    HU Ru-fu; GUI Zhong-hua; CHEN Xiao-ping; SUN Qing-hong

    2006-01-01

    Virtual dynamic optimization design can avoid the repeated process from design to trial-manufacture and test. The designer can analyze and optimize the product structures in virtual visualization environment. The design cycle is shortened and the cost is reduced. The paper analyzed the peculiarity of virtual optimization design, and put forwards the thought and flow to implement virtual optimization design. The example to optimize the internal grinder was studied via establishing precise finite element model, modifying the layout of Stiffened Plates and designing parameters of the worktable, and using the technology of modal frequency revision and the technology of multiple tuned damper.The result of optimization design compared the new grinder with the original grinder shows that the entire machine's first orders natural frequency is enhanced by 17%, and the response displacement of the grinding-head has dropped by 28% under the first order natural frequency and by 41% under second order natural frequency. Finally, the dynamic performance of the internal grinder was optimized.

  3. Investigation of Dynamic Force/Vibration Transmission Characteristics of Four-Square Type Gear Durability Test Machines

    Science.gov (United States)

    Kahraman, Ahmet

    2002-01-01

    In this study, design requirements for a dynamically viable, four-square type gear test machine are investigated. Variations of four-square type gear test machines have been in use for durability and dynamics testing of both parallel- and cross-axis gear set. The basic layout of these machines is illustrated. The test rig is formed by two gear pairs, of the same reduction ratio, a test gear pair and a reaction gear pair, connected to each other through shafts of certain torsional flexibility to form an efficient, closed-loop system. A desired level of constant torque is input to the circuit through mechanical (a split coupling with a torque arm) or hydraulic (a hydraulic actuator) means. The system is then driven at any desired speed by a small DC motor. The main task in hand is the isolation of the test gear pair from the reaction gear pair under dynamic conditions. Any disturbances originated at the reaction gear mesh might potentially travel to the test gearbox, altering the dynamic loading conditions of the test gear mesh, and hence, influencing the outcome of the durability or dynamics test. Therefore, a proper design of connecting structures becomes a major priority. Also, equally important is the issue of how close the operating speed of the machine is to the resonant frequencies of the gear meshes. This study focuses on a detailed analysis of the current NASA Glenn Research Center gear pitting test machine for evaluation of its resonance and vibration isolation characteristics. A number of these machines as the one illustrated has been used over last 30 years to establish an extensive database regarding the influence of the gear materials, processes surface treatments and lubricants on gear durability. This study is intended to guide an optimum design of next generation test machines for the most desirable dynamic characteristics.

  4. An Integrated Approach of Fuzzy Linguistic Preference Based AHP and Fuzzy COPRAS for Machine Tool Evaluation.

    Science.gov (United States)

    Nguyen, Huu-Tho; Md Dawal, Siti Zawiah; Nukman, Yusoff; Aoyama, Hideki; Case, Keith

    2015-01-01

    Globalization of business and competitiveness in manufacturing has forced companies to improve their manufacturing facilities to respond to market requirements. Machine tool evaluation involves an essential decision using imprecise and vague information, and plays a major role to improve the productivity and flexibility in manufacturing. The aim of this study is to present an integrated approach for decision-making in machine tool selection. This paper is focused on the integration of a consistent fuzzy AHP (Analytic Hierarchy Process) and a fuzzy COmplex PRoportional ASsessment (COPRAS) for multi-attribute decision-making in selecting the most suitable machine tool. In this method, the fuzzy linguistic reference relation is integrated into AHP to handle the imprecise and vague information, and to simplify the data collection for the pair-wise comparison matrix of the AHP which determines the weights of attributes. The output of the fuzzy AHP is imported into the fuzzy COPRAS method for ranking alternatives through the closeness coefficient. Presentation of the proposed model application is provided by a numerical example based on the collection of data by questionnaire and from the literature. The results highlight the integration of the improved fuzzy AHP and the fuzzy COPRAS as a precise tool and provide effective multi-attribute decision-making for evaluating the machine tool in the uncertain environment.

  5. An Integrated Approach of Fuzzy Linguistic Preference Based AHP and Fuzzy COPRAS for Machine Tool Evaluation.

    Directory of Open Access Journals (Sweden)

    Huu-Tho Nguyen

    Full Text Available Globalization of business and competitiveness in manufacturing has forced companies to improve their manufacturing facilities to respond to market requirements. Machine tool evaluation involves an essential decision using imprecise and vague information, and plays a major role to improve the productivity and flexibility in manufacturing. The aim of this study is to present an integrated approach for decision-making in machine tool selection. This paper is focused on the integration of a consistent fuzzy AHP (Analytic Hierarchy Process and a fuzzy COmplex PRoportional ASsessment (COPRAS for multi-attribute decision-making in selecting the most suitable machine tool. In this method, the fuzzy linguistic reference relation is integrated into AHP to handle the imprecise and vague information, and to simplify the data collection for the pair-wise comparison matrix of the AHP which determines the weights of attributes. The output of the fuzzy AHP is imported into the fuzzy COPRAS method for ranking alternatives through the closeness coefficient. Presentation of the proposed model application is provided by a numerical example based on the collection of data by questionnaire and from the literature. The results highlight the integration of the improved fuzzy AHP and the fuzzy COPRAS as a precise tool and provide effective multi-attribute decision-making for evaluating the machine tool in the uncertain environment.

  6. Research on Dynamic Modeling and Application of Kinetic Contact Interface in Machine Tool

    Directory of Open Access Journals (Sweden)

    Dan Xu

    2016-01-01

    Full Text Available A method is presented which is a kind of combining theoretic analysis and experiment to obtain the equivalent dynamic parameters of linear guideway through four steps in detail. From statics analysis, vibration model analysis, dynamic experiment, and parameter identification, the dynamic modeling of linear guideway is synthetically studied. Based on contact mechanics and elastic mechanics, the mathematic vibration model and the expressions of basic mode frequency are deduced. Then, equivalent stiffness and damping of guideway are obtained in virtue of single-freedom-degree mode fitting method. Moreover, the investigation above is applied in a certain gantry-type machining center; and through comparing with simulation model and experiment results, both availability and correctness are validated.

  7. Spindle Thermal Error Optimization Modeling of a Five-axis Machine Tool

    Institute of Scientific and Technical Information of China (English)

    Qianjian GUO; Shuo FAN; Rufeng XU; Xiang CHENG; Guoyong ZHAO; Jianguo YANG

    2017-01-01

    Aiming at the problem of low machining accuracy and uncontrollable thermal errors of NC machine tools,spindle thermal error measurement,modeling and compensation of a two turntable five-axis machine tool are researched.Measurement experiment of heat sources and thermal errors are carried out,and GRA(grey relational analysis) method is introduced into the selection of temperature variables used for thermal error modeling.In order to analyze the influence of different heat sources on spindle thermal errors,an ANN (artificial neural network) model is presented,and ABC(artificial bee colony) algorithm is introduced to train the link weights of ANN,a new ABCNN(Artificial bee colony-based neural network) modeling method is proposed and used in the prediction of spindle thermal errors.In order to test the prediction performance of ABC-NN model,an experiment system is developed,the prediction results of LSR (least squares regression),ANN and ABC-NN are compared with the measurement results of spindle thermal errors.Experiment results show that the prediction accuracy of ABC-NN model is higher than LSR and ANN,and the residual error is smaller than 3 μm,the new modeling method is feasible.The proposed research provides instruction to compensate thermal errors and improve machining accuracy of NC machine tools.

  8. Spindle Thermal Error Optimization Modeling of a Five-axis Machine Tool

    Science.gov (United States)

    Guo, Qianjian; Fan, Shuo; Xu, Rufeng; Cheng, Xiang; Zhao, Guoyong; Yang, Jianguo

    2017-03-01

    Aiming at the problem of low machining accuracy and uncontrollable thermal errors of NC machine tools, spindle thermal error measurement, modeling and compensation of a two turntable five-axis machine tool are researched. Measurement experiment of heat sources and thermal errors are carried out, and GRA(grey relational analysis) method is introduced into the selection of temperature variables used for thermal error modeling. In order to analyze the influence of different heat sources on spindle thermal errors, an ANN (artificial neural network) model is presented, and ABC(artificial bee colony) algorithm is introduced to train the link weights of ANN, a new ABC-NN(Artificial bee colony-based neural network) modeling method is proposed and used in the prediction of spindle thermal errors. In order to test the prediction performance of ABC-NN model, an experiment system is developed, the prediction results of LSR (least squares regression), ANN and ABC-NN are compared with the measurement results of spindle thermal errors. Experiment results show that the prediction accuracy of ABC-NN model is higher than LSR and ANN, and the residual error is smaller than 3 μm, the new modeling method is feasible. The proposed research provides instruction to compensate thermal errors and improve machining accuracy of NC machine tools.

  9. End mill tools integration in CNC machining for rapid manufacturing processes: simulation studies

    Directory of Open Access Journals (Sweden)

    Muhammed Nafis Osman Zahid

    2015-01-01

    Full Text Available Computer numerical controlled (CNC machining has been recognized as a manufacturing process that is capable of producing metal parts with high precision and reliable quality, whereas many additive manufacturing methods are less capable in these respects. The introduction of a new layer-removal methodology that utilizes an indexing device to clamp the workpiece can be used to extend CNC applications into the realm of rapid manufacturing (CNC-RM processes. This study aims to improve the implementation of CNC machining for RM by formulating a distinct approach to integrate end mill tools during finishing processes. A main objective is to enhance process efficiency by minimizing the staircasing effect of layer removal so as to improve the quality of machined parts. In order to achieve this, different types of end mill tools are introduced to cater for specific part surfaces during finishing operations. Virtual machining simulations are executed to verify the method and the implications. The findings indicate the advantages of the approach in terms of cutting time and excess volume left on the parts. It is shown that using different tools for finishing operations will improve the capabilities of CNC machining for rapid manufacturing applications.

  10. Thermal Error Modeling of a Machine Tool Using Data Mining Scheme

    Science.gov (United States)

    Wang, Kun-Chieh; Tseng, Pai-Chang

    In this paper the knowledge discovery technique is used to build an effective and transparent mathematic thermal error model for machine tools. Our proposed thermal error modeling methodology (called KRL) integrates the schemes of K-means theory (KM), rough-set theory (RS), and linear regression model (LR). First, to explore the machine tool's thermal behavior, an integrated system is designed to simultaneously measure the temperature ascents at selected characteristic points and the thermal deformations at spindle nose under suitable real machining conditions. Second, the obtained data are classified by the KM method, further reduced by the RS scheme, and a linear thermal error model is established by the LR technique. To evaluate the performance of our proposed model, an adaptive neural fuzzy inference system (ANFIS) thermal error model is introduced for comparison. Finally, a verification experiment is carried out and results reveal that the proposed KRL model is effective in predicting thermal behavior in machine tools. Our proposed KRL model is transparent, easily understood by users, and can be easily programmed or modified for different machining conditions.

  11. Efficient thermal error prediction in a machine tool using finite element analysis

    Science.gov (United States)

    Mian, Naeem S.; Fletcher, Simon; Longstaff, Andrew P.; Myers, Alan

    2011-08-01

    Thermally induced errors have a major significance on the positional accuracy of a machine tool. Heat generated during the machining process produces thermal gradients that flow through the machine structure causing linear and nonlinear thermal expansions and distortions of associated complex discrete structures, producing deformations that adversely affect structural stability. The heat passes through structural linkages and mechanical joints where interfacial parameters such as the roughness and form of the contacting surfaces affect the thermal resistance and thus the heat transfer coefficients. This paper presents a novel offline technique using finite element analysis (FEA) to simulate the effects of the major internal heat sources such as bearings, motors and belt drives of a small vertical milling machine (VMC) and the effects of ambient temperature pockets that build up during the machine operation. Simplified models of the machine have been created offline using FEA software and evaluated experimental results applied for offline thermal behaviour simulation of the full machine structure. The FEA simulated results are in close agreement with the experimental results ranging from 65% to 90% for a variety of testing regimes and revealed a maximum error range of 70 µm reduced to less than 10 µm.

  12. A numerical study of ultraprecision machining of monocrystalline silicon with laser nano-structured diamond tools by atomistic simulation

    Science.gov (United States)

    Dai, Houfu; Chen, Genyu; Zhou, Cong; Fang, Qihong; Fei, Xinjiang

    2017-01-01

    Three-dimension molecular dynamics (MD) simulations is employed to investigate the ultraprecision machining of single crystal silicon with structured nanoscale diamond tool fabricated by laser. The advantages and disadvantages of diamond machining using structured tools are discussed in comparison with those of using non-structured tools. The von Mises stress distribution, hydrostatic stress distribution, atomic displacement, stress, the radial distribution function, cutting forces, frictional coefficient, subsurface temperature and potential energy during the nanometric machining process are studied. A theoretical analysis model is also established to investigate the subsurface damage mechanism by analyzing the distribution of residual stress during the nanoscale machining process. The results show that a structured nanoscale tool in machining brittle material silicon causes a smaller hydrostatic stress, a less compressive normal stress σxx and σyy , a lower temperature and a smaller cutting force. However, the structured nanoscale tool machining results in smaller chip volume and more beta-silicon phase. Besides, the friction coefficient for tool with V-shape groove is smaller than those for non-structured tools and other structured nanoscale tools. This means that the tool with V-shape groove can reduce the resistance to cutting during the nanoscale machining process. In addition, the results also point out that the potential energy of subsurface atoms and the number of other atoms for pyramid-structured tool are much smaller than those of using non-structured tools and other structured nanoscale tools.

  13. THEORETICAL PREDICTION OF TOOL-CHIP CONTACT LENGTH IN ORTHOGONAL METAL MACHINING BY COMPUTER SIMULATION

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A method for determination of tool-chip contact length is theoretically presented in orthogonal metal machining. By using computer simulation and based on the analyses of the elastro-plastic deformation with lagrangian finite element method in the deformation zone,the accumulated representative length of the low layer, the tool-chip contact length of the chip contacting the tool rake are calculated, experimental studies are also carried out with 0.2% carbon steel. It is shown that the tool-chip contact lengths obtained from computer simulation have a good agreement with those of measured values.

  14. Generated spiral bevel gears: Optimal machine-tool settings and tooth contact analysis

    Science.gov (United States)

    Litvin, F. L.; Tsung, W. J.; Coy, J. J.; Heine, C.

    1985-01-01

    Geometry and kinematic errors were studied for Gleason generated spiral bevel gears. A new method was devised for choosing optimal machine settings. These settings provide zero kinematic errors and an improved bearing contact. The kinematic errors are a major source of noise and vibration in spiral bevel gears. The improved bearing contact gives improved conditions for lubrication. A computer program for tooth contact analysis was developed, and thereby the new generation process was confirmed. The new process is governed by the requirement that during the generation process there is directional constancy of the common normal of the contacting surfaces for generator and generated surfaces of pinion and gear.

  15. Generated spiral bevel gears - Optimal machine-tool settings and tooth contact analysis

    Science.gov (United States)

    Litvin, F. L.; Tsung, W.-J.; Coy, J. J.; Heine, C.

    1985-01-01

    Geometry and kinematic errors were studied for Gleason generated spiral bevel gears. A new method was devised for choosing optimal machine settings. These settings provide zero kinematic errors and an improved bearing contact. The kinematic errors are a major source of noise and vibration in spiral bevel gears. The improved bearing contact gives improved conditions for lubrication. A computer program for tooth contact analysis was developed, and thereby the new generation process was confirmed. The new process is governed by the requirement that during the generation process there is directional constancy of the common normal of the contacting surfaces for generator and generated surfaces of pinion and gear.

  16. Five-Axis Machine Tool Condition Monitoring Using dSPACE Real-Time System

    Science.gov (United States)

    Sztendel, S.; Pislaru, C.; Longstaff, A. P.; Fletcher, S.; Myers, A.

    2012-05-01

    This paper presents the design, development and SIMULINK implementation of the lumped parameter model of C-axis drive from GEISS five-axis CNC machine tool. The simulated results compare well with the experimental data measured from the actual machine. Also the paper describes the steps for data acquisition using ControlDesk and hardware-in-the-loop implementation of the drive models in dSPACE real-time system. The main components of the HIL system are: the drive model simulation and input - output (I/O) modules for receiving the real controller outputs. The paper explains how the experimental data obtained from the data acquisition process using dSPACE real-time system can be used for the development of machine tool diagnosis and prognosis systems that facilitate the improvement of maintenance activities.

  17. Recent progresses in the exploration of machine learning methods as in-silico ADME prediction tools.

    Science.gov (United States)

    Tao, L; Zhang, P; Qin, C; Chen, S Y; Zhang, C; Chen, Z; Zhu, F; Yang, S Y; Wei, Y Q; Chen, Y Z

    2015-06-23

    In-silico methods have been explored as potential tools for assessing ADME and ADME regulatory properties particularly in early drug discovery stages. Machine learning methods, with their ability in classifying diverse structures and complex mechanisms, are well suited for predicting ADME and ADME regulatory properties. Recent efforts have been directed at the broadening of application scopes and the improvement of predictive performance with particular focuses on the coverage of ADME properties, and exploration of more diversified training data, appropriate molecular features, and consensus modeling. Moreover, several online machine learning ADME prediction servers have emerged. Here we review these progresses and discuss the performances, application prospects and challenges of exploring machine learning methods as useful tools in predicting ADME and ADME regulatory properties.

  18. A new damage diagnosis approach for NC machine tools based on hybrid Stationary subspace analysis

    Science.gov (United States)

    Gao, Chen; Zhou, Yuqing; Ren, Yan

    2017-05-01

    This paper focused on the damage diagnosis for NC machine tools and put forward a damage diagnosis method based on hybrid Stationary subspace analysis (SSA), for improving the accuracy and visibility of damage identification. First, the observed single sensor signal was reconstructed to multi-dimensional signals by the phase space reconstruction technique, as the inputs of SSA. SSA method was introduced to separate the reconstructed data into stationary components and non-stationary components without the need for independency and prior information of the origin signals. Subsequently, the selected non-stationary components were analysed for training LS-SVM (Least Squares Support Vector Machine) classifier model, in which several statistic parameters in the time and frequency domains were exacted as the sample of LS-SVM. An empirical analysis in NC milling machine tools is developed, and the result shows high accuracy of the proposed approach.

  19. Research on Remote Video Monitoring System Used for Numerical Control Machine Tools Based on Embedded Technology

    Institute of Scientific and Technical Information of China (English)

    LIU Quan; QU Xuehong; ZHOU Henglin; LONG Yihong

    2006-01-01

    This paper designed an embedded video monitoring system using DSP(Digital Signal Processing) and ARM(Advanced RISC Machine). This system is an important part of self-service operation of numerical control machine tools. At first the analog input signals from the CCD(Charge Coupled Device) camera are transformed into digital signals, and then output to the DSP system, where the video sequence is encoded according to the new generation image compressing standard called H.264. The code will be transmitted to the ARM system through xBus, and then be packed in the ARM system and transmitted to the client port through the gateway. Web technology, embedded technology and image compressing as well as coding technology are integrated in the system, which can be widely used in self-service operation of numerical control machine tools and intelligent robot control areas.

  20. A Tool for Assessing the Text Legibility of Digital Human Machine Interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Roger Lew; Ronald L. Boring; Thomas A. Ulrich

    2015-08-01

    A tool intended to aid qualified professionals in the assessment of the legibility of text presented on a digital display is described. The assessment of legibility is primarily for the purposes of designing and analyzing human machine interfaces in accordance with NUREG-0700 and MIL-STD 1472G. The tool addresses shortcomings of existing guidelines by providing more accurate metrics of text legibility with greater sensitivity to design alternatives.

  1. Effect of milling strategy and tool geometry on machining cost when cutting titanium alloys

    Directory of Open Access Journals (Sweden)

    Conradie, Pieter

    2015-11-01

    Full Text Available The growing demands on aerospace manufacturers to cut more difficult-to-machine materials at increasing material removal rates require that manufacturers enhance their machining capability. This requires a better understanding of the effects of milling strategies and tool geometries on cutting performance. Ti6Al4V is the most widely-used titanium alloy in the aerospace industry, due to its unique combination of properties. These properties also make the alloy very challenging to machine. Complex aerospace geometries necessitate large material removal, and are therefore generally associated with high manufacturing costs. To investigate the effect of milling strategy and tool geometry on cutting performance, the new constant engagement milling strategy was firstly compared with a conventional approach. Thereafter, a component was milled with different cutting tool geometries. Cost savings of more than 40% were realised by using a constant engagement angle milling strategy. A reduction of 38% in machining time was achieved by using tools with a land on the rake side of the cutting edge. These incremental improvements made it possible to enhance the overall performance of the cutting process.

  2. Machine Tool Layout: Outlining a Basic Shape on Flat Steel. Fordson Bilingual Demonstration Project.

    Science.gov (United States)

    Ochsner, Alan

    This vocational instructional module on outlining a basic shape on flat steel is one of eight such modules designed to assist recently arrived Arab students, limited in English proficiency (LEP), in critical instructional areas in a comprehensive high school. Goal stated for this module is for the student enrolled in a machine tool course to…

  3. Influence of Workpiece Material on Tool Wear Performance and Tribofilm Formation in Machining Hardened Steel

    Directory of Open Access Journals (Sweden)

    Junfeng Yuan

    2016-04-01

    Full Text Available In addition to the bulk properties of a workpiece material, characteristics of the tribofilms formed as a result of workpiece material mass transfer to the friction surface play a significant role in friction control. This is especially true in cutting of hardened materials, where it is very difficult to use liquid based lubricants. To better understand wear performance and the formation of beneficial tribofilms, this study presents an assessment of uncoated mixed alumina ceramic tools (Al2O3+TiC in the turning of two grades of steel, AISI T1 and AISI D2. Both workpiece materials were hardened to 59 HRC then machined under identical cutting conditions. Comprehensive characterization of the resulting wear patterns and the tribofilms formed at the tool/workpiece interface were made using X-ray Photoelectron Spectroscopy and Scanning Electron Microscopy. Metallographic studies on the workpiece material were performed before the machining process and the surface integrity of the machined part was investigated after machining. Tool life was 23% higher when turning D2 than T1. This improvement in cutting tool life and wear behaviour was attributed to a difference in: (1 tribofilm generation on the friction surface and (2 the amount and distribution of carbide phases in the workpiece materials. The results show that wear performance depends both on properties of the workpiece material and characteristics of the tribofilms formed on the friction surface.

  4. On the Physics of Machining Titanium Alloys: Interactions between Cutting Parameters, Microstructure and Tool Wear

    Directory of Open Access Journals (Sweden)

    Mohammed Nouari

    2014-07-01

    Full Text Available The current work deals with the analysis of mechanisms involved during the machining process of titanium alloys. Two different materials were chosen for the study: Ti-6Al-4V and Ti-55531. The objective was to understand the effect of all cutting parameters on the tool wear behavior and stability of the cutting process. The investigations were focused on the mechanisms of the chip formation process and their interaction with tool wear. At the microstructure scale, the analysis confirms the intense deformation of the machined surface and shows a texture modification. As the cutting speed increases, cutting forces and temperature show different progressions depending on the considered microstructure (Ti-6Al-4V or Ti-55531 alloy. Results show for both materials that the wear process is facilitated by the high cutting temperature and the generation of high stresses. The analysis at the chip-tool interface of friction and contact nature (sliding or sticking contact shows that machining Ti55531 often exhibits an abrasion wear process on the tool surface, while the adhesion and diffusion modes followed by the coating delamination process are the main wear modes when machining the usual Ti-6Al-4V alloy.

  5. Mathematics for the Workplace. Applications from Machine Tool Technology (Michelin Tire Corporation). A Teacher's Guide.

    Science.gov (United States)

    Wallace, Johnny M.; Stewart, Grover

    This module presents a real-world context in which mathematics skills (geometry and trigonometry) are used as part of a daily routine. The context is the machine tool technology field, and the module aims to help students develop the ability to analyze diagrams in order to make mathematical computations. The modules, which features applications…

  6. Technology and Jobs: Computer-Aided Design. Numerical-Control Machine-Tool Operators. Office Automation.

    Science.gov (United States)

    Stanton, Michael; And Others

    1985-01-01

    Three reports on the effects of high technology on the nature of work include (1) Stanton on applications and implications of computer-aided design for engineers, drafters, and architects; (2) Nardone on the outlook and training of numerical-control machine tool operators; and (3) Austin and Drake on the future of clerical occupations in automated…

  7. MACHINE TOOL OPERATOR--GENERAL, ENTRY, SUGGESTED GUIDE FOR A TRAINING COURSE.

    Science.gov (United States)

    RONEY, MAURICE W.; AND OTHERS

    THE PURPOSE OF THIS CURRICULUM GUIDE IS TO ASSIST THE ADMINISTRATOR AND INSTRUCTOR IN PLANNING AND DEVELOPING MANPOWER DEVELOPMENT AND TRAINING PROGRAMS TO PREPARE MACHINE TOOL OPERATORS FOR ENTRY-LEVEL POSITIONS. THE COURSE OUTLINE PROVIDES UNITS IN -- (1) ORIENTATION, (2) BENCH WORK, (3) SHOP MATHEMATICS, (4) BLUEPRINT READING AND SKETCHING, (5)…

  8. Determination of real machine-tool settings and minimization of real surface deviation by computerized inspection

    Science.gov (United States)

    Litvin, Faydor L.; Kuan, Chihping; Zhang, YI

    1991-01-01

    A numerical method is developed for the minimization of deviations of real tooth surfaces from the theoretical ones. The deviations are caused by errors of manufacturing, errors of installment of machine-tool settings and distortion of surfaces by heat-treatment. The deviations are determined by coordinate measurements of gear tooth surfaces. The minimization of deviations is based on the proper correction of initially applied machine-tool settings. The contents of accomplished research project cover the following topics: (1) Descriptions of the principle of coordinate measurements of gear tooth surfaces; (2) Deviation of theoretical tooth surfaces (with examples of surfaces of hypoid gears and references for spiral bevel gears); (3) Determination of the reference point and the grid; (4) Determination of the deviations of real tooth surfaces at the points of the grid; and (5) Determination of required corrections of machine-tool settings for minimization of deviations. The procedure for minimization of deviations is based on numerical solution of an overdetermined system of n linear equations in m unknowns (m much less than n ), where n is the number of points of measurements and m is the number of parameters of applied machine-tool settings to be corrected. The developed approach is illustrated with numerical examples.

  9. Adaption of commercial off the shelf modules for reconfigurable machine tool design

    CSIR Research Space (South Africa)

    Mpofu, K

    2008-01-01

    Full Text Available of design of machine tools to achieve flexibility through reconfigurability is discussed. Highlights of the implication of this method and it’s repercussions to basic modules, alternate modules and additional modules are analysed. The role of the computer...

  10. Research on Key Technologies of Unit-Based CNC Machine Tool Assembly Design

    Directory of Open Access Journals (Sweden)

    Zhongqi Sheng

    2014-01-01

    Full Text Available Assembly is the part that produces the maximum workload and consumed time during product design and manufacturing process. CNC machine tool is the key basic equipment in manufacturing industry and research on assembly design technologies of CNC machine tool has theoretical significance and practical value. This study established a simplified ASRG for CNC machine tool. The connection between parts, semantic information of transmission, and geometric constraint information were quantified to assembly connection strength to depict the assembling difficulty level. The transmissibility based on trust relationship was applied on the assembly connection strength. Assembly unit partition based on assembly connection strength was conducted, and interferential assembly units were identified and revised. The assembly sequence planning and optimization of parts in each assembly unit and between assembly units was conducted using genetic algorithm. With certain type of high speed CNC turning center, as an example, this paper explored into the assembly modeling, assembly unit partition, and assembly sequence planning and optimization and realized the optimized assembly sequence of headstock of CNC machine tool.

  11. Manufacturing process applications team (MATEAM). [technology transfer in the areas of machine tools and robots

    Science.gov (United States)

    1979-01-01

    The transfer of NASA technology to the industrial sector is reported. Presentations to the machine tool and robot industries and direct technology transfers of the Adams Manipulator arm, a-c motor control, and the bolt tension monitor are discussed. A listing of proposed RTOP programs with strong potential is included. A detailed description of the rotor technology available to industry is given.

  12. Tool-path planning for free-form surface high-speed high-resolution machining using torus cutter

    Institute of Scientific and Technical Information of China (English)

    WANG Yu-han; LI Ru-qiong; WU Zu-yu; CHEN Zhao-neng

    2006-01-01

    In CNC machining, two essential components decide the accuracy and machining time for a sculptured surface: one is the step-size interval, the other is the tool-path interval. Due to the limitation of the conventional method for calculating the tool-path interval, it cannot satisfy the machining requirement for highspeed and high-resolution machining. Accordingly, for high-speed and high-resolution machining, the current study proposes a new tool-path interval algorithm, plus a variable step-size algorithm for NURBS. Furthermore,a new type cutter, which can improve the cutting efficiency, is investigated in the paper. The transversal equation of the torus cutter onto the flat plan is given in this paper. The tool-path interval is calculated with the transversal equation and the proposed algorithm. The illustrated example shows that the redundant tool paths can be reduced because an accurate tool-path interval could be calculated.

  13. A novel vending machine for supplying root canal tools during surgery.

    Science.gov (United States)

    Nelson, Carl A; Hossain, S G M; Al-Okaily, Ala'a; Ong, Jason

    2012-02-01

    A root canal surgery involves the successive use of several tools one after another. Typically dozens of tools are laid out for possible use, and the process of tool selection is done manually. This is a rather inefficient process and uses up a large area on the mobile cart or cabinet of the dental chair due to the large number of tools. In this article, a novel 'tool vending machine' is introduced which will be capable of solving those problems and at the same time move a step closer to robot-assisted dental surgery. The tool vending machine was designed considering the needs of the dentists and also from the perspective of the entire product life cycle. For these reasons the design process was implemented using a rigorous analysis of effective manufacturing processes and product quality. To show the feasibility of using such a machine in improving work efficiency during operations, a study of the associated motion patterns and the required time increments were demonstrated.

  14. Analysis of the Rotary Ultrasonic Machining Mechanism

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Ultrasonic machining (USM) is considered as an effective method for machining hard and brittle materials such as glass, engineering ceramics, semiconductors, diamonds, metal composites and so on. However, the low material removal rate due to using abrasive slurry limits further application of USM. Rotary ultrasonic machining (rotary USM) superimposes rotational movement on the tool head that vibrates at ultrasonic frequency (20 kHz) simultaneously. The tool is made of mild steel coated or bonded with diamon...

  15. Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

    OpenAIRE

    2014-01-01

    Poly-crystalline cubic boron nitride (PCBN) is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM) is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materia...

  16. Precise gouging-free tool orientations for 5-axis CNC machining

    KAUST Repository

    Kim, Yong-Joon

    2014-08-19

    We present a precise approach to the generation of optimized collision-free and gouging-free tool paths for 5-axis CNC machining of freeform NURBS surfaces using flat-end and rounded-end (bull nose) tools having cylindrical shank. To achieve high approximation quality, we employ analysis of hyper-osculating circles (HOCs) (Wang et al., 1993a,b), that have third order contact with the target surface, and lead to a locally collision-free configuration between the tool and the target surface. At locations where an HOC is not possible, we aim at a double tangential contact among the tool and the target surface, and use it as a bridge between the feasible HOC tool paths. We formulate all such possible two-contact configurations as systems of algebraic constraints and solve them. For all feasible HOCs and two-contact configurations, we perform a global optimization to find the tool path that maximizes the approximation quality of the machining, while being gouge-free and possibly satisfying constraints on the tool tilt and the tool acceleration. We demonstrate the effectiveness of our approach via several experimental results.

  17. ZERO TRANSMISSION AND ITS APPLICATION IN HIGH SPEED CNC MACHINE TOOLS

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    In order to realize high speed machining,the special requirements for the transmission and sturctrue of CNC machine tool have to be satisfied.A high speed spindle unit driven by a builtin motor is developed.An oilwater heat exchange system is used for cooling the spindle motor.The spindle is supported by Si4N3 ceramic ball angular contact bearings.An oilair lubricator is used to lubricate and cool the spindle bearings.Some special structures are taken for balancing the spindle.

  18. Comparative aspects about the studying methods of cast irons machinability, based on the tool wear

    Science.gov (United States)

    Carausu, C.; Pruteanu, O.

    2016-08-01

    The paper presents some considerations of the authors, regarding the studying methods of the cast irons machinability, based on the tools wear on drilling operations. Are described the conditions in which the experimental researches were conducted, intended to offer an overview on drilling machinability of some cast irons categories. It is presented a comparison between long-term methods and short-term methods, for determining the optimal speed chipping of a grey cast iron with lamellar graphite, with average values of tensile strength. Are described: the research methodology, obtained results and conclusions drawn after the results analysis.

  19. Monitoring systems for the analysis of vibrations and balance of rotary machines; Sistemas de monitorizacion para el analisis de vibraciones y balanceo de maquinas rotatorias

    Energy Technology Data Exchange (ETDEWEB)

    Serrano R, Luis E; Ramirez Solis, J. Antonio; Munoz Q, Rodolfo [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico)

    2004-07-01

    Often, the rotary equipment faults appear as an abnormal vibration or a change in the characteristic vibration pattern of each machine. From here the importance of counting on tools that allow to acquire and to analyze the vibration signals of the equipment while it is in operation. The Gerencia de Turbomaquinaria has worked in this field since the end of the Seventies, developing diagnosis systems based on personal computers that allow the monitoring of the dynamic behavior of the rotary equipment. The main system of this type that the Instituto de Investigaciones Electricas (IIE), nowadays offers, is the Computerized System for Dynamic Analysis, also known by its abbreviation in Spanish as: SICAD II. This was designed under the requirements of the Comision Federal de Electricidad (CFE) to collect, measure and analyze vibration data of rotary equipment. It is also used in the balance, fault diagnosis and the solution of problems in rotary equipment. The system SICAD II is portable and versatile system with which vibrations are acquired, measured and analyzed by means of the presentation of the data in graphical formats of different type and application. [Spanish] A menudo, las fallas en los equipos rotatorios se manifiestan como una vibracion anormal o como un cambio en el patron de vibraciones caracteristico de cada maquina. De ahi la importancia de contar con herramientas que permitan adquirir y analizar las senales de vibracion de los equipos mientras estan en operacion. La Gerencia de Turbomaquinaria ha trabajado en este campo desde finales de la decada de los setenta, desarrollando sistemas de diagnostico basados en computadoras personales que permiten monitorear el comportamiento dinamico de los equipos rotatorios. El principal sistema de este tipo que ofrece, actualmente, el Instituto de Investigaciones Electricas (IIE) es el Sistema Computarizado para Analisis Dinamico, conocido tambien por su abreviacion como: Sicad II. Este fue disenado bajo los

  20. MECHANISMS OF CUTTING BLADE WEAR AND THEIR INFLUENCE ON CUTTING ABILITY OF THE TOOL DURING MACHINING OF SPECIAL ALLOYS

    Directory of Open Access Journals (Sweden)

    Tomáš Zlámal

    2016-09-01

    Full Text Available With increased requirements for quality and shelf life of machined parts there is also a higher share of the use of material with specific properties that are identified by the term “superalloys”. These materials differ from common steels by mechanical and physical properties that cause their worse machinability. During machining of “superalloys” worse machinability has negative influence primarily on the amount of cutting edge wear, which shortens durability of the cutting tool. The goal of experimental activity shown in this contribution is to determine individual mechanisms of the cutting edge wear and their effects on the cutting ability during high speed machining of nickel superalloy. A specific exchangeable cutting insert made from cubic boric nitride was used for machining of the 625 material according to ASM 5666F. The criteria to evaluate cutting ability and durability of the cutting tool became selected parameters of surface integrity and quality of the machined surface.

  1. Réduction active des vibrations et des bruits d'une machine électrique par la stratégie de commande.

    OpenAIRE

    Geoffriault, Maud

    2015-01-01

    This work takes place in the context of the development of powertrains for electric vehicles. Those developments have raised new issues such as noise and vibrations of electrical machines, which are important issues in automotive applications. The aim of this thesis is to develop control laws dedicated to the reduction of currents harmonics that are responsible for vibration harmonics.In that purpose, different parts of the system have been modelled. Parameters of the electrical model of the ...

  2. Calculation and analysis for stiffness of the thrust aerostatic bearing of ultra-precision machine tools

    Science.gov (United States)

    Lu, Lihua; Zhao, Ziqiang; Liang, Yingchun; Zhang, Longjiang

    2010-10-01

    The single point diamond turning (SPDT) lathe of vertical flying cutting milling style is one important ultra-precision machining method for Large-aperture optics. To realize ultra-precision machining with SPDT technology, the turning spindle of the machine tools should be with higher stiffness and stability. In this paper, based on finite element method (FEM), an iterative procedure is proposed and implemented to solve the fluid dynamic model and structure model for simulation the couple of air pressure and structure flexibility. Simulation results show that pressure in the air gap makes the plate deform and this deformation produced by the pressure adversely modifies the pressure distribution. Experimental results indicate that the method can predict the aerostatic spindle stiffness accurately, the prediction error is about 2.04%. These results show a relevant influence of the structural flexibility of the bearing on its static performance.

  3. Adaptive tool servo diamond turning for enhancing machining efficiency and surface quality of freeform optics.

    Science.gov (United States)

    Zhu, Zhiwei; To, Suet

    2015-08-10

    Fast tool servo/ slow tool servo (FTS/STS) diamond turning is a very promising technique for the generation of freeform optics. However, the currently adopted constant scheme for azimuth sampling and side-feeding motion possesses no adaptation to surface shape variation, leading to the non-uniform surface quality and low machining efficiency. To overcome this defect, this paper reports on a novel adaptive tool servo (ATS) diamond turning technique which is essentially based on the novel two-degree-of-freedom (2-DOF) FTS/STS. In the ATS, the sampling interval and the side-feeding motion are actively controlled at any cutting point to adapt the machining process to shape variation of the desired surface, making both the sampling induced interpolation error and the side-feeding induced residual tool mark be within the desired tolerances. Characteristic of the required cutting motion suggests that besides the conventional z-axis servo motion, another servo motion along the x-axis synthesizing by the c-axis is mandatory for implementing the ATS. Comparative studies of surface generation of typical micro-structured surfaces in FTS/STS and ATS are thoroughly conducted both theoretically and experimentally. The result demonstrates that the ATS outperforms the FTS/STS with improved surface quality while simultaneously enhanced machining efficiency.

  4. Minimizing the total tardiness for the tool change scheduling problem on parallel machines

    Directory of Open Access Journals (Sweden)

    Antonio Costa

    2016-04-01

    Full Text Available This paper deals with the total tardiness minimization problem in a parallel machines manufacturing environment where tool change operations have to be scheduled along with jobs. The mentioned issue belongs to the family of scheduling problems under deterministic machine availability restrictions. A new model that considers the effects of the tool wear on the quality characteristics of the worked product is proposed. Since no mathematical programming-based approach has been developed by literature so far, two distinct mixed integer linear programming models, able to schedule jobs as well as tool change activities along the provided production horizon, have been devised. The former is an adaptation of a well-known model presented by the relevant literature for the single machine scheduling problem with tool changes. The latter has been specifically developed for the issue at hand. After a theoretical analysis aimed at revealing the differences between the proposed mathematical models in terms of computational complexity, an extensive experimental campaign has been fulfilled to assess performances of the proposed methods under the CPU time viewpoint. Obtained results have been statistically analyzed through a properly arranged ANOVA analysis.

  5. Development of atmospheric pressure plasma processing machine tool for large aperture optics

    Science.gov (United States)

    Su, Xing; Wu, Yangong; Zhang, Peng; Xin, Qiang; Wang, Bo

    2016-10-01

    In recent years, major projects, such as National Ignition Facility and Laser Mégajoule, have generated great demands for large aperture optics with high surface accuracy and low Subsurface Damage (SSD) at the mean time. In order to remove SSD and improve surface quality, optics is fabricated by sub-aperture polishing. However, the efficiency of the sub-aperture polishing has been a bottleneck step for the optics manufacturing. Atmospheric Pressure Plasma Processing (APPP) as an alternate method offers high potential for speeding up the polishing process. This technique is based on chemical etching, hence there is no physical contact and no damage is induced. In this paper, a fast polishing machine tool is presented which is designed for fast polishing of the large aperture optics using APPP. This machine tool employs 3PRS-XY hybrid structure as its framework. There is a platform in the 3PRS parallel module to support the plasma generating system. And the large work piece is placed on the XY stage. In order to realize the complex motion trajectory for polishing the freeform optics, five axis of the tool operate simultaneously. To overcome the complexity of inverse kinematics calculation, a dedicated motion control system is also designed for speeding up the motion response. For high removal rate, the individual influence of several key processing parameters is investigated. And under specific production condition, this machine tool offers a high material over 30mm3/min for fused silica substrates. This results shows that APPP machine tool has a strong potential for fast polishing large optics without introducing SSD.

  6. Repurposing mainstream CNC machine tools for laser-based additive manufacturing

    Science.gov (United States)

    Jones, Jason B.

    2016-04-01

    The advent of laser technology has been a key enabler for industrial 3D printing, known as Additive Manufacturing (AM). Despite its commercial success and unique technical capabilities, laser-based AM systems are not yet able to produce parts with the same accuracy and surface finish as CNC machining. To enable the geometry and material freedoms afforded by AM, yet achieve the precision and productivity of CNC machining, hybrid combinations of these two processes have started to gain traction. To achieve the benefits of combined processing, laser technology has been integrated into mainstream CNC machines - effectively repurposing them as hybrid manufacturing platforms. This paper reviews how this engineering challenge has prompted beam delivery innovations to allow automated changeover between laser processing and machining, using standard CNC tool changers. Handling laser-processing heads using the tool changer also enables automated change over between different types of laser processing heads, further expanding the breadth of laser processing flexibility in a hybrid CNC. This paper highlights the development, challenges and future impact of hybrid CNCs on laser processing.

  7. An Analysis Methodology for Stochastic Characteristic of Volumetric Error in Multiaxis CNC Machine Tool

    Directory of Open Access Journals (Sweden)

    Qiang Cheng

    2013-01-01

    Full Text Available Traditional approaches about error modeling and analysis of machine tool few consider the probability characteristics of the geometric error and volumetric error systematically. However, the individual geometric error measured at different points is variational and stochastic, and therefore the resultant volumetric error is aslo stochastic and uncertain. In order to address the stochastic characteristic of the volumetric error for multiaxis machine tool, a new probability analysis mathematical model of volumetric error is proposed in this paper. According to multibody system theory, a mean value analysis model for volumetric error is established with consideration of geometric errors. The probability characteristics of geometric errors are obtained by statistical analysis to the measured sample data. Based on probability statistics and stochastic process theory, the variance analysis model of volumetric error is established in matrix, which can avoid the complex mathematics operations during the direct differential. A four-axis horizontal machining center is selected as an illustration example. The analysis results can reveal the stochastic characteristic of volumetric error and are also helpful to make full use of the best workspace to reduce the random uncertainty of the volumetric error and improve the machining accuracy.

  8. Dust Emission Induced By Friction Modifications At Tool Chip Interface In Dry Machining In MMCp

    Science.gov (United States)

    Kremer, Arnaud; El Mansori, Mohamed

    2011-01-01

    This paper investigates the relationship between dust emission and tribological conditions at the tool-chip interface when machining Metal Matrix composite reinforced with particles (MMCp) in dry mode. Machining generates aerosols that can easily be inhaled by workers. Aerosols may be composed of oil mist, tool material or alloying elements of workpiece material. Bar turning tests were conducted on a 2009 aluminum alloy reinforced with different level of Silicon Carbide particles (15, 25 and 35% of SiCp). Variety of PCD tools and nanostructured diamond coatings were used to analyze their performances on air pollution. A spectrometer was used to detect airborne aerosol particles in the size range between 0.3μm to 20 μm and to sort them in 15 size channels in real time. It was used to compare the effects of test parameters on dust emission. Observations of tool face and chip morphology reveal the importance of friction phenomena. It was demonstrated that level of friction modifies chip curvature and dust emission. The increase of level of reinforcement increase the chip segmentation and decrease the contact length and friction area. A "running in" phenomenon with important dust emission appeared with PCD tool due to the tool rake face flatness. In addition dust generation is more sensitive to edge integrity than power consumption.

  9. ASSESSMENT OF INFLUENCE OF CUTTING TOOL BREAKAGE ON DRIVE LIFE TIME OF CUTTING UNIT OF HEADING MACHINE

    Directory of Open Access Journals (Sweden)

    О.Е. SHABAEV

    2014-01-01

    Full Text Available In this work a necessity to develop means of technical diagnostics of cutter's performance without stopping heading machine was grounded. There was theoretically demonstrated the possibility of essential decrease in life time of transmission elements of cutting unit during prolonged work of heading machine with broken cutting tool. It was defined that influence of cutting tool breakage on life time of transmission elements depends on cutting tool position on cutting head according to the assembly drawing.

  10. Imperfect preventive maintenance for numerical control machine tools with log-linear virtual age process

    Institute of Scientific and Technical Information of China (English)

    郭俊锋; 芮执元; 冯瑞成; 魏兴春

    2014-01-01

    Based on the log-linear virtual age process, an imperfect preventive maintenance policy for numerical control (NC) machine tools with random maintenance quality is proposed. The proposed model is a combination of the Kijima type virtual age model and the failure intensity adjustment model. Maintenance intervals of the proposed hybrid model are derived when the failure intensity increase factor and the restoration factor are both random variables with uniform distribution. The optimal maintenance policy in infinite time horizon is presented. A numerical example is given when the failures of NC machine tools are described by the log-linear process. Finally, a discussion is presented to show how the optimal results depend on the different cost parameters.

  11. Analysis of the Thermal Characteristics of Machine Tool Feed System Based on Finite Element Method

    Science.gov (United States)

    Mao, Xiaobo; Mao, Kuanmin; Du, Yikang; Wang, Fengyun; Yan, Bo

    2017-09-01

    The loading of mobile heat source and boundary conditions setting are difficult problems in the analysis of thermal characteristics of machine tools. Taking the machine tool feed system as an example, a novel method for loading of mobile heat source was proposed by establishing a function which was constructed by the heat source and time. The convective heat transfer coefficient is the key parameter of boundary conditions, and it varies with the temperature. In this paper, a model of “variable convection heat transfer coefficient” was proposed, and the setting of boundary conditions of thermal analysis was closer to the real situation. Finally, comparing results of above method and experimental data, the accuracy and validity of this method was proved, meanwhile, the simulation calculation and simulation time was reducing greatly.

  12. Balancing Vibrations at Harmonic Frequencies by Injecting Harmonic Balancing Signals into the Armature of a Linear Motor/Alternator Coupled to a Stirling Machine

    Science.gov (United States)

    Holliday, Ezekiel S. (Inventor)

    2014-01-01

    Vibrations at harmonic frequencies are reduced by injecting harmonic balancing signals into the armature of a linear motor/alternator coupled to a Stirling machine. The vibrations are sensed to provide a signal representing the mechanical vibrations. A harmonic balancing signal is generated for selected harmonics of the operating frequency by processing the sensed vibration signal with adaptive filter algorithms of adaptive filters for each harmonic. Reference inputs for each harmonic are applied to the adaptive filter algorithms at the frequency of the selected harmonic. The harmonic balancing signals for all of the harmonics are summed with a principal control signal. The harmonic balancing signals modify the principal electrical drive voltage and drive the motor/alternator with a drive voltage component in opposition to the vibration at each harmonic.

  13. Influence of forest machine function on operator exposure to whole-body vibration in a cut-to-length timber harvester.

    Science.gov (United States)

    Sherwin, L M; Owende, P M O; Kanali, C L; Lyons, J; Ward, S M

    2004-09-15

    The influence of machine function (tree felling and processing, and machine movement over the terrain) on operator exposure to whole-body vibration in a cut-to-length (CTL) timber harvester was evaluated. Vibrations were measured on the seat and the cabin chassis in three orthogonal (x, y, z) axes for the tree felling and processing, and during motion on a test track. It was found that the level of vibration transmitted to the operator during felling and processing was mainly affected by the tree size (diameter). For tree diameter at breast height (dbh) range of 0.25-0.35 m that was investigated, the vertical (z-axis) vibration component during processing increased by up to 300%, and increased by 50% during felling. However, the associated vibration levels were not sufficient to pose any serious health risks to the operator for an exposure limit of 8 h. Vibration at the operator seat and cabin chassis was predominant in the lateral (y-axis) and vertical (z-axis) respectively, during vehicle motion over the standard test track. Vibration peaks of approximately 0.20 and 0.17 ms(-2) occurred at 5 and 3.2 Hz respectively.

  14. Methods of In-Process On-Machine Auto-Inspection of Dimensional Error and Auto-Compensation of Tool Wear for Precision Turning

    Directory of Open Access Journals (Sweden)

    Shih-Ming Wang

    2016-04-01

    Full Text Available The purpose of this study is mainly to develop an information and communication technology (ICT-based intelligent dimension inspection and tool wear compensation method for precision tuning. With the use of vibration signal processing/characteristics analysis technology combined with ICT, statistical analysis, and diagnosis algorithms, the method can be used to proceed with an on-line dimension inspection and on-machine tool wear auto-compensation for the turning process. Meanwhile, the method can also monitor critical tool life to identify the appropriate time for cutter replacement to reduce machining costs and improve the production efficiency of the turning process. Compared to the traditional ways, the method offers the advantages of requiring less manpower, and having better production efficiency, high tool life, fewer scrap parts, and low costs for inspection instruments. Algorithms and diagnosis threshold values for the detection, cutter wear compensation, and cutter life monitoring were developed. In addition, a bilateral communication module utilizing FANUC Open CNC (computer numerical control Application Programming Interface (API Spec was developed for the on-line extraction of instant NC (numerical control codes for monitoring and transmit commands to CNC controllers for cutter wear compensation. With use of local area networks (LAN to deliver the detection and correction information, the proposed method was able to remotely control the on-machine monitoring process and upload the machining and inspection data to a remote central platform for further production optimization. The verification experiments were conducted on a turning production line. The results showed that the system provided 93% correction for size inspection and 100% correction for cutter wear compensation.

  15. Age, diversification and survival in the German machine tool industry, 1953-2002

    OpenAIRE

    Coad, Alex; Guenther, Christina

    2011-01-01

    We focus on the relationship of age and diversification patterns of German machine tool manufacturers in the post war era. Based on trade journals we track the entire firm populations' product portfolio development throughout each firm's lifetime. We distinguish between 'minor diversification' and 'major diversification', where these two concepts refer to adding a new product variation within a familiar submarket, or expanding the product portfolio into new submarkets. Our analysis reveals fo...

  16. STUDY ON NEW METHOD OF IDENTIFYING GEOMETRIC ERROR PARAMETERS FOR NC MACHINE TOOLS

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The methods of identifying geometric error parameters for NC machine tools are introduced. According to analyzing and comparing the different methods, a new method-displacement method with 9 lines is developed based on the theories of the movement errors of multibody system (MBS). A lot of experiments are also made to obtain 21 terms geometric error parameters by using the error identification software based on the new method.

  17. Position-independent geometric error identification and global sensitivity analysis for the rotary axes of five-axis machine tools

    Science.gov (United States)

    Guo, Shijie; Jiang, Gedong; Zhang, Dongsheng; Mei, Xuesong

    2017-04-01

    Position-independent geometric errors (PIGEs) are the fundamental errors of a five-axis machine tool. In this paper, to identify ten PIGEs peculiar to the rotary axes of five-axis machine tools with a tilting head, the mathematic model of the ten PIGEs is deduced and four measuring patterns are proposed. The measuring patterns and identifying method are validated on a five-axis machine tool with a tilting head, and the ten PIGEs of the machine tool are obtained. The sensitivities of the four adjustable PIGEs of the machine tool in different measuring patterns are analyzed by the Morris global sensitivity analysis method and the modifying method, and the procedure of the four adjustable PIGEs of the machine tool is given accordingly. Experimental results show that after and before modifying the four adjustable PIGEs, the average compensate rate reached 52.7%. It is proved that the proposed measuring, identifying, analyzing and modifying method are effective for error measurement and precision improvement of the five-axis machine tool.

  18. Near-Source Error Sensor Strategies for Active Vibration Isolation of Machines

    NARCIS (Netherlands)

    Beijers, C.A.J.; Basten, T.G.H.; de Boer, Andries; van den Brink, D.R.; Verheij, J.W.; Sas, P; de Munck, M.

    2004-01-01

    Due to lightweight construction of vehicles and ships, the reduction of structure borne interior noise problems with passive isolation of engine vibrations might be not sufficient. To improve the isolation, a combination of passive and active isolation techniques can be used (so-called hybrid isolat

  19. In-vitro tensile testing machine for vibration study of fresh rabbit Achilles tendon

    Science.gov (United States)

    Revel, Gian M.; Scalise, Alessandro; Scalise, Lorenzo; Pianosi, Antonella

    2001-10-01

    A lot of people, overall athletic one suffer from tendinitis or complete rupture of the Achilles tendon. This structure becomes inflamed and damaged mainly from a variety of mechanical forces and sometimes due to metabolic problems, such as diabetes or arthritis. Over the past three decades extensive studies have been performed on the structural and mechanical properties of Achilles tendon trying to explain the constitutive equations to describe and foresee tendon behavior. Among the various mechanical parameters, the vibrational behavior is also of interest. Several investigations are performed in order to study how the Achilles tendon vibrations influence the response of the muscle proprioception and human posture. The present article describes how in vitro tensile experiments can be performed, taking into account the need to simulate physiological condition of Achilles tendon and thus approaching some opened problems in the design of the experimental set-up. A new system for evaluating tendon vibrations by non contact techniques is proposed. Preliminary simple elongation tests are made extracting the main mechanical parameters: stress and strain at different fixed stretches, in order to characterize the tissue. Finally, a vibration study is made at each pretensioned tendon level evaluating the oscillating curves caused by a small hammer.

  20. Near-source error sensor strategies for active vibration isolation of machines

    NARCIS (Netherlands)

    Beijers, C.A.J.; Basten, T.G.H.; Brink, van den D.R.; Verheij, J.W.; Boer, de A.

    2004-01-01

    Due to lightweight construction of vehicles and ships, the reduction of structure borne interior noise problems with passive isolation of engine vibrations might be not sufficient. To improve the isolation, a combination of passive and active isolation techniques can be used (so-called hybrid isolat

  1. An integrated multidisciplinary design optimization method for computer numerical control machine tool development

    Directory of Open Access Journals (Sweden)

    Zaifang Zhang

    2015-02-01

    Full Text Available Computer numerical control machine tool is a typical complex product related with multidisciplinary fields, complex structure, and high-performance requirements. It is difficult to identify the overall optimal solution of the machine tool structure for their multiple objectives. A new integrated multidisciplinary design optimization method is then proposed by using a Latin hypercube sampling, a Kriging approximate model, and a multi-objective genetic algorithm. Design space and parametric model are built by choosing appropriate design variables and their value ranges. Samples in design space are generated by optimal Latin hypercube method, and design variable contributions for design performance are discussed for aiding the designer’s judgments. The Kriging model is built by using polynomial approximation according to the response outputs of these samples. The multidisciplinary design model is established based on three optimization objectives, that is, setting mass, optimum deformation, and first-order natural frequency, and two constraints, that is, second-order natural frequency and third-order natural frequency. The optimal solution is identified by using a multi-objective genetic algorithm. The proposed method is applied in a multidisciplinary optimization case study for a typical computer numerical control machine tool. In the optimal solution, the mass decreases by 3.35% and the first-order natural frequency increases by 4.34% in contrast to the original solution.

  2. Bayesian Reliability Modeling and Assessment Solution for NC Machine Tools under Small-sample Data

    Institute of Scientific and Technical Information of China (English)

    YANG Zhaojun; KAN Yingnan; CHEN Fei; XU Binbin; CHEN Chuanhai; YANG Chuangui

    2015-01-01

    Although Markov chain Monte Carlo(MCMC) algorithms are accurate, many factors may cause instability when they are utilized in reliability analysis; such instability makes these algorithms unsuitable for widespread engineering applications. Thus, a reliability modeling and assessment solution aimed at small-sample data of numerical control(NC) machine tools is proposed on the basis of Bayes theories. An expert-judgment process of fusing multi-source prior information is developed to obtain the Weibull parameters’ prior distributions and reduce the subjective bias of usual expert-judgment methods. The grid approximation method is applied to two-parameter Weibull distribution to derive the formulas for the parameters’ posterior distributions and solve the calculation difficulty of high-dimensional integration. The method is then applied to the real data of a type of NC machine tool to implement a reliability assessment and obtain the mean time between failures(MTBF). The relative error of the proposed method is 5.8020×10-4 compared with the MTBF obtained by the MCMC algorithm. This result indicates that the proposed method is as accurate as MCMC. The newly developed solution for reliability modeling and assessment of NC machine tools under small-sample data is easy, practical, and highly suitable for widespread application in the engineering field; in addition, the solution does not reduce accuracy.

  3. High productivity machining of holes in Inconel 718 with SiAlON tools

    Science.gov (United States)

    Agirreurreta, Aitor Arruti; Pelegay, Jose Angel; Arrazola, Pedro Jose; Ørskov, Klaus Bonde

    2016-10-01

    Inconel 718 is often employed in aerospace engines and power generation turbines. Numerous researches have proven the enhanced productivity when turning with ceramic tools compared to carbide ones, however there is considerably less information with regard to milling. Moreover, no knowledge has been published about machining holes with this type of tools. Additional research on different machining techniques, like for instance circular ramping, is critical to expand the productivity improvements that ceramics can offer. In this a 3D model of the machining and a number of experiments with SiAlON round inserts have been carried out in order to evaluate the effect of the cutting speed and pitch on the tool wear and chip generation. The results of this analysis show that three different types of chips are generated and also that there are three potential wear zones. Top slice wear is identified as the most critical wear type followed by the notch wear as a secondary wear mechanism. Flank wear and adhesion are also found in most of the tests.

  4. Influence of export control policy on the competitiveness of machine tool producing organizations

    Science.gov (United States)

    Ahrstrom, Jeffrey D.

    The possible influence of export control policies on producers of export controlled machine tools is examined in this quantitative study. International market competitiveness theories hold that market controlling policies such as export control regulations may influence an organization's ability to compete (Burris, 2010). Differences in domestic application of export control policy on machine tool exports may impose throttling effects on the competitiveness of participating firms (Freedenberg, 2010). Commodity shipments from Japan, Germany, and the United States to the Russian market will be examined using descriptive statistics; gravity modeling of these specific markets provides a foundation for comparison to actual shipment data; and industry participant responses to a user developed survey will provide additional data for analysis using a Kruskal-Wallis one-way analysis of variance. There is scarce academic research data on the topic of export control effects within the machine tool industry. Research results may be of interest to industry leadership in market participation decisions, advocacy arguments, and strategic planning. Industry advocates and export policy decision makers could find data of interest in supporting positions for or against modifications of export control policies.

  5. The Influence of Tool Geometry towards Cutting Performance in Machining Aluminium 7075

    Directory of Open Access Journals (Sweden)

    Muhammad Syafik Jumali

    2017-01-01

    Full Text Available Aerospace industries often use Computer Numerical Control (CNC machining in manufacturing aerospace parts. Aluminium 7075 is the most common material used as aircraft components. This research aims to produce end mill with optimum geometry in terms of the helix angle, primary radial relief angle and secondary relief angle. End mills with different geometry parameters are tested on Aluminium 7075 and data on surface roughness and tool wear were collected. The results were then analysed to determine which parameters brought the optimum result with regards to surface roughness and tool wear.

  6. A Machine Learning Tool for Weighted Regressions in Time, Discharge, and Season

    Directory of Open Access Journals (Sweden)

    Alexander Maestre

    2014-01-01

    Full Text Available A new machine learning tool has been developed to classify water stations with similar water quality trends. The tool is based on the statistical method, Weighted Regressions in Time, Discharge, and Season (WRTDS, developed by the United States Geological Survey (USGS to estimate daily concentrations of water constituents in rivers and streams based on continuous daily discharge data and discrete water quality samples collected at the same or nearby locations. WRTDS is based on parametric survival regressions using a jack-knife cross validation procedure that generates unbiased estimates of the prediction errors. One of the disadvantages of WRTDS is that it needs a large number of samples (n > 200 collected during at least two decades. In this article, the tool is used to evaluate the use of Boosted Regression Trees (BRT as an alternative to the parametric survival regressions for water quality stations with a small number of samples. We describe the development of the machine learning tool as well as an evaluation comparison of the two methods, WRTDS and BRT. The purpose of the tool is to evaluate the reduction in variability of the estimates by clustering data from nearby stations with similar concentration and discharge characteristics. The results indicate that, using clustering, the predicted concentrations using BRT are in general higher than the observed concentrations. In addition, it appears that BRT generates higher sum of square residuals than the parametric survival regressions.

  7. Mathematical support for automated geometry analysis of lathe machining of oblique peakless round–nose tools

    Science.gov (United States)

    Filippov, A. V.; Tarasov, S. Yu; Podgornyh, O. A.; Shamarin, N. N.; Filippova, E. O.

    2017-01-01

    Automatization of engineering processes requires developing relevant mathematical support and a computer software. Analysis of metal cutting kinematics and tool geometry is a necessary key task at the preproduction stage. This paper is focused on developing a procedure for determining the geometry of oblique peakless round-nose tool lathe machining with the use of vector/matrix transformations. Such an approach allows integration into modern mathematical software packages in distinction to the traditional analytic description. Such an advantage is very promising for developing automated control of the preproduction process. A kinematic criterion for the applicable tool geometry has been developed from the results of this study. The effect of tool blade inclination and curvature on the geometry-dependent process parameters was evaluated.

  8. Optimization of machining and vibration parameters for residual stresses minimization in ultrasonic assisted turning of 4340 hardened steel.

    Science.gov (United States)

    Sharma, Varun; Pandey, Pulak M

    2016-08-01

    The residual stresses generated in the machined work piece have detrimental effect on fatigue life, corrosion resistance and tribological properties. However, the effect of cutting and vibration parameters on residual stresses in Ultrasonic Assisted Turning (UAT) has not been dealt with. The present paper highlights the effect of feed rate, depth of cut, cutting velocity and percentage intensity of ultrasonic power on residual stress generation. XRD analysis has been carried out to measure the residual stress while turning 4340 hardened steel using UAT. The experiments were performed based on response surface methodology to develop statistical model for residual stress. The outcome of ANOVA revealed that percentage intensity and feed rate significantly affect the residual stress generation. The significant interactions between process parameters have also been presented tin order to understand the thermo-mechanical mechanism responsible for residual stress generation.

  9. Modeling the Relationship between Vibration Features and Condition Parameters Using Relevance Vector Machines for Health Monitoring of Rolling Element Bearings under Varying Operation Conditions

    Directory of Open Access Journals (Sweden)

    Lei Hu

    2015-01-01

    Full Text Available Rotational speed and load usually change when rotating machinery works. Both this kind of changing operational conditions and machine fault could make the mechanical vibration characteristics change. Therefore, effective health monitoring method for rotating machinery must be able to adjust during the change of operational conditions. This paper presents an adaptive threshold model for the health monitoring of bearings under changing operational conditions. Relevance vector machines (RVMs are used for regression of the relationships between the adaptive parameters of the threshold model and the statistical characteristics of vibration features. The adaptive threshold model is constructed based on these relationships. The health status of bearings can be indicated via detecting whether vibration features exceed the adaptive threshold. This method is validated on bearings running at changing speeds. The monitoring results show that this method is effective as long as the rotational speed is higher than a relative small value.

  10. Vibration suppression of thin-walled workpiece machining considering external damping properties based on magnetorheological fluids flexible fixture

    Institute of Scientific and Technical Information of China (English)

    Ma Junjin; Zhang Dinghua; Wu Baohai; Luo Ming; Chen Bing

    2016-01-01

    Milling of the thin-walled workpiece in the aerospace industry is a critical process due to the high flexibility of the workpiece. In this paper, a flexible fixture based on the magnetorheological (MR) fluids is designed to investigate the regenerative chatter suppression during the machining. Based on the analysis of typical structural components in the aerospace industry, a general complex thin-walled workpiece with fixture and damping constraint can be equivalent as a rectangular can-tilever beam. On the basis of the equivalent models, natural frequency and mode shape function of the thin-walled workpiece is obtained according to the Euler–Bernoulli beam assumptions. Then, the displacement response function of the bending vibration of the beam is represented by the pro-duct of all the mode shape function and the generalized coordinate. Furthermore, a dynamic equa-tion of the workpiece-fixture system considering the external damping factor is proposed using the Lagrangian method in terms of all the mode shape function and the generalized coordinate, and the response of system under the dynamic cutting force is calculated to evaluate the stability of the milling process under damping control. Finally, the feasibility and effectiveness of the proposed approach are validated by the impact hammer experiments and several machining tests.

  11. A tool for urban soundscape evaluation applying Support Vector Machines for developing a soundscape classification model.

    Science.gov (United States)

    Torija, Antonio J; Ruiz, Diego P; Ramos-Ridao, Angel F

    2014-06-01

    To ensure appropriate soundscape management in urban environments, the urban-planning authorities need a range of tools that enable such a task to be performed. An essential step during the management of urban areas from a sound standpoint should be the evaluation of the soundscape in such an area. In this sense, it has been widely acknowledged that a subjective and acoustical categorization of a soundscape is the first step to evaluate it, providing a basis for designing or adapting it to match people's expectations as well. In this sense, this work proposes a model for automatic classification of urban soundscapes. This model is intended for the automatic classification of urban soundscapes based on underlying acoustical and perceptual criteria. Thus, this classification model is proposed to be used as a tool for a comprehensive urban soundscape evaluation. Because of the great complexity associated with the problem, two machine learning techniques, Support Vector Machines (SVM) and Support Vector Machines trained with Sequential Minimal Optimization (SMO), are implemented in developing model classification. The results indicate that the SMO model outperforms the SVM model in the specific task of soundscape classification. With the implementation of the SMO algorithm, the classification model achieves an outstanding performance (91.3% of instances correctly classified).

  12. The Use of Response Surface Methodology to Optimize Parameter Adjustments in CNC Machine Tools

    Directory of Open Access Journals (Sweden)

    Shao-Hsien Chen

    2014-01-01

    Full Text Available This paper mainly covers a research intended to improve the circular accuracy of CNC machine tools and the adjustment and analysis of the main controller parameters applied to improve accuracy. In this study, controller analysis software was used to detect the adjustment status of the servo parameters of the feed axis. According to the FANUC parameter manual, the parameter address, frequency, response measurements, and the one-fourth corner acceleration and deceleration measurements of the machine tools were adjusted. The experimental design (DOE was adopted in this study for taking circular measurements and engaging in the planning and selection of important parameter data. The Minitab R15 software was adopted to predict the experimental data analysis, while the seminormal probability map, Plato, and analysis of variance (ANOVA were adopted to determine the impacts of the significant parameter factors and the interactions among them. Additionally, based on the response surface map and contour plot, the optimal values were obtained. In addition, comparison and verification were conducted through the Taguchi method, regression analysis to improved machining accuracy and efficiency. The unadjusted error was 7.8 μm; through the regression analysis method, the error was 5.8 μm and through the Taguchi analysis method, the error was 6.4 μm.

  13. Vibration reliability analysis for aeroengine compressor blade based on support vector machine response surface method

    Institute of Scientific and Technical Information of China (English)

    GAO Hai-feng; BAI Guang-chen

    2015-01-01

    To ameliorate reliability analysis efficiency for aeroengine components, such as compressor blade, support vector machine response surface method (SRSM) is proposed. SRSM integrates the advantages of support vector machine (SVM) and traditional response surface method (RSM), and utilizes experimental samples to construct a suitable response surface function (RSF) to replace the complicated and abstract finite element model. Moreover, the randomness of material parameters, structural dimension and operating condition are considered during extracting data so that the response surface function is more agreeable to the practical model. The results indicate that based on the same experimental data, SRSM has come closer than RSM reliability to approximating Monte Carlo method (MCM); while SRSM (17.296 s) needs far less running time than MCM (10958 s) and RSM (9840 s). Therefore, under the same simulation conditions, SRSM has the largest analysis efficiency, and can be considered a feasible and valid method to analyze structural reliability.

  14. Structure-based sampling and self-correcting machine learning for accurate calculations of potential energy surfaces and vibrational levels

    Science.gov (United States)

    Dral, Pavlo O.; Owens, Alec; Yurchenko, Sergei N.; Thiel, Walter

    2017-06-01

    We present an efficient approach for generating highly accurate molecular potential energy surfaces (PESs) using self-correcting, kernel ridge regression (KRR) based machine learning (ML). We introduce structure-based sampling to automatically assign nuclear configurations from a pre-defined grid to the training and prediction sets, respectively. Accurate high-level ab initio energies are required only for the points in the training set, while the energies for the remaining points are provided by the ML model with negligible computational cost. The proposed sampling procedure is shown to be superior to random sampling and also eliminates the need for training several ML models. Self-correcting machine learning has been implemented such that each additional layer corrects errors from the previous layer. The performance of our approach is demonstrated in a case study on a published high-level ab initio PES of methyl chloride with 44 819 points. The ML model is trained on sets of different sizes and then used to predict the energies for tens of thousands of nuclear configurations within seconds. The resulting datasets are utilized in variational calculations of the vibrational energy levels of CH3Cl. By using both structure-based sampling and self-correction, the size of the training set can be kept small (e.g., 10% of the points) without any significant loss of accuracy. In ab initio rovibrational spectroscopy, it is thus possible to reduce the number of computationally costly electronic structure calculations through structure-based sampling and self-correcting KRR-based machine learning by up to 90%.

  15. The investigation of electromagnetic radial force and associated vibration in permanent magnet synchronous machines

    OpenAIRE

    Liang, Wenyi

    2017-01-01

    The rising public awareness of climate change and urban air pollution has been one of the key drivers for transport electrification. Such trend drastically accelerates the quest for high-power-and-torque-density electric drive systems. The rare-earth permanent magnet synchronous machine, with its excellent steady-state and dynamic characteristics, has been the ideal candidate for these applications. Specifically, the fractional-slot and concentrated-winding configuration is wid...

  16. DEPENDENCE OF THE SLIDER DEFORMATION AND MACHINING PRECISION ON THE MULTIPURPOSE MACHINE-TOOL COMPLEX OF VM SERIES

    Directory of Open Access Journals (Sweden)

    Berezhnoy S. B.

    2016-04-01

    Full Text Available The article is devoted to the development of high-tech metal-working industry, as well as to the use of unmanned technology. We recommended measures to improve the accuracy and quality of manufacturing of complex and large workpieces weighing up to 100 tons. To date, the technical level of many economy sectors is largely determined by the level of the production means. Based on the engineering development there is an overall automation and mechanization of production and industry processes, construction, agriculture, transport and other industries. We analyzed forms of slide sections, of errors affecting the accuracy of the workpieces manufacturing. We made simulation of the cutting forces and sliders deformations. Solved measures increase manufacturing accuracy based on multi-purpose machine tool systems of VM series. We held the analysis of the dependence of cutting forces, a slider form on its strain in different types of processing. We obtained a graph of cutting force and precision manufacturing. We defined the optimal shape of the slider cross section to increase the rigidity and reduce the slide deformation in metal cutting

  17. DEVELOPMENT OF FUZZY MODEL FOR POWDER MIXED ELECTRO DISCHARGE MACHINING USING COPPER AND GRAPHITE TOOL MATERIAL

    Directory of Open Access Journals (Sweden)

    SONI S.S.

    2012-09-01

    Full Text Available This paper describes development of fuzzy logic model for powder mixed electro discharge machining (PMEDM process. The developed fuzzy model implements triangular and trapezoidal membership functionsfor fuzzification and centre-of-area method for defuzzification processes. The process parameters selected as control variables for experimental work were tool material, type of powder, concentration of powder in dielectric medium and peak current. The machining operation was conducted by using copper and graphite as electrode material on mild steel workpiece material. The powder additives used in the experiment were aluminum and silicon because of their significantly different electrical and thermal properties. The dielectric fluid used was kerosene. The response parameters selected are material removal rate and electrode wear rate. Response surfaces are developed from the developed fuzzy system model. Also exemplar plot developed to compare the responses from fuzzy model and experiment.

  18. Tool Wear Analysis due to Machining In Super Austenitic Stainless Steel

    Directory of Open Access Journals (Sweden)

    Polishetty Ashwin

    2017-01-01

    Full Text Available This paper presents tool wear study when a machinability test was applied using milling on Super Austenitic Stainless Steel AL6XN alloy. Eight milling trials were performed under two cutting speeds, 100 m/min and 150 m/min, combined with two feed rates at 0.1mm/tooth and 0.15 mm/tooth and two depth of cuts at 2 mm and 3 mm. An Alicona 3D optical surface profilometer was used to scan cutting inserts flank and rake face areas for wear. Readings such as maximum and minimum deviations were extracted and used to analyse the outcomes. Results showed various types of wear were generated on the tool rake and flank faces. The common formed wear was the crater wear. The formation of the build-up edge was observed on the rake face of the cutting tool.

  19. Rotary Ultrasonic Machining of Poly-Crystalline Cubic Boron Nitride

    Directory of Open Access Journals (Sweden)

    Kuruc Marcel

    2014-12-01

    Full Text Available Poly-crystalline cubic boron nitride (PCBN is one of the hardest material. Generally, so hard materials could not be machined by conventional machining methods. Therefore, for this purpose, advanced machining methods have been designed. Rotary ultrasonic machining (RUM is included among them. RUM is based on abrasive removing mechanism of ultrasonic vibrating diamond particles, which are bonded on active part of rotating tool. It is suitable especially for machining hard and brittle materials (such as glass and ceramics. This contribution investigates this advanced machining method during machining of PCBN.

  20. Design, analysis and testing of a new piezoelectric tool actuator for elliptical vibration turning

    Science.gov (United States)

    Lin, Jieqiong; Han, Jinguo; Lu, Mingming; Yu, Baojun; Gu, Yan

    2017-08-01

    A new piezoelectric tool actuator (PETA) for elliptical vibration turning has been developed based on a hybrid flexure hinge connection. Two double parallel four-bar linkage mechanisms and two right circular flexure hinges were chosen to guide the motion. The two input displacement directional stiffness were modeled according to the principle of virtual work modeling method and the kinematic analysis was conducted theoretically. Finite element analysis was used to carry out static and dynamic analyses. To evaluate the performance of the developed PETA, off-line experimental tests were carried out to investigate the step responses, motion strokes, resolutions, parasitic motions, and natural frequencies of the PETA along the two input directions. The relationship between input displacement and output displacement, as well as the tool tip’s elliptical trajectory in different phase shifts was analyzed. By using the developed PETA mechanism, micro-dimple patterns were generated as the preliminary application to demonstrate the feasibility and efficiency of PETA for elliptical vibration turning.

  1. 旋转超声磨削加工中影响磨具寿命的结构参数优化%Optimization of structure parameters affecting tool life in rotary ultrasonic grinding machining

    Institute of Scientific and Technical Information of China (English)

    荆君涛; 刘运凤; 李占杰; 饶小双

    2013-01-01

    This paper focused on improving machining precision and reducing the machining errors caused by tool wearing in a Rotary Ultrasonic Grinding Machining(RUGM). The relation model between the ultrasonic vibration tool life and the grit sizes, grit concentration and the inner circle radius of a tool was established, and the parameters affecting ultrasonic vibration tool life were optimized. First, the second order model of ultrasonic vibration tool life was established for a bronze-bonded ultrasonic vibrating tool with Response Surface Methodology (RSM), and the model was fitted based on Box - Behnken experiments. Then the ultrasonic vibration tool life model was checked by effectiveness and significance tests. Finally, the cross-fertilization between the various influence factors and the tool life was analyzed through fitting the response surface and the contour between ultrasonic vibration tool life and factors, and the ultrasonic vibration tool parameters were optimized. The results indicate that the wear capacity of ultrasonic vibration tool is only 0. 006 9 mm, after removing 9 600 mm3 for Si3N4 ceramics materials with density of 85%, when the grit size is D98. 85, grit concentration is 77. 36, and the inner circle radius of the tool is 5. 34 mm. It satisfies the finish machining requirements for RUGM.%为了提高陶瓷基零部件的旋转超声磨削加工精度,降低磨具磨损造成的加工误差,建立了超声振动磨具寿命与磨粒粒度、浓度、磨具内圆直径等结构参数间关系的数学模型,对影响超声振动磨具寿命的结构参数进行了优化.首先,基于响应曲面法,建立了青铜基超声振动磨具二阶寿命模型,通过Box-Behnken实验对超声振动磨具寿命模型进行了拟合.然后,通过有效性和显著性检验,验证了所建立的超声振动磨具寿命模型.最后,通过拟合影响因子与超声振动磨具寿命关系的响应曲面和等高线,分析了各因素对磨具寿命的交叉影

  2. A planning quality evaluation tool for prostate adaptive IMRT based on machine learning

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Xiaofeng; Ge Yaorong; Li Taoran; Thongphiew, Danthai; Yin Fangfang; Wu, Q Jackie [Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27708 (United States); Department of Biomedical Engineering, Wake Forest University Health Sciences, Medical Center Boulevard, Winston-Salem, North Carolina 27106 (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27708 (United States); Department of Radiation Oncology, Brody School of Medicine, East Carolina University, Greenville, North Carolina 27834 (United States); Department of Radiation Oncology, Duke University Medical Center, Durham, North Carolina 27708 (United States)

    2011-02-15

    Purpose: To ensure plan quality for adaptive IMRT of the prostate, we developed a quantitative evaluation tool using a machine learning approach. This tool generates dose volume histograms (DVHs) of organs-at-risk (OARs) based on prior plans as a reference, to be compared with the adaptive plan derived from fluence map deformation. Methods: Under the same configuration using seven-field 15 MV photon beams, DVHs of OARs (bladder and rectum) were estimated based on anatomical information of the patient and a model learned from a database of high quality prior plans. In this study, the anatomical information was characterized by the organ volumes and distance-to-target histogram (DTH). The database consists of 198 high quality prostate plans and was validated with 14 cases outside the training pool. Principal component analysis (PCA) was applied to DVHs and DTHs to quantify their salient features. Then, support vector regression (SVR) was implemented to establish the correlation between the features of the DVH and the anatomical information. Results: DVH/DTH curves could be characterized sufficiently just using only two or three truncated principal components, thus, patient anatomical information was quantified with reduced numbers of variables. The evaluation of the model using the test data set demonstrated its accuracy {approx}80% in prediction and effectiveness in improving ART planning quality. Conclusions: An adaptive IMRT plan quality evaluation tool based on machine learning has been developed, which estimates OAR sparing and provides reference in evaluating ART.

  3. Step kinematic calibration of a 3-DOF planar parallel kinematic machine tool

    Institute of Scientific and Technical Information of China (English)

    CHANG Peng; WANG JinSong; LI TieMin; LIU XinJun; GUAN LiWen

    2008-01-01

    This paper presents a novel step kinematic calibration method for a 3 degree-of-freedom (DOF) planar parallel kinematic machine tool, based on the minimal linear combinations (MLCs) of error parameters. The method using mapping of linear combinations of parameters in error transfer multi-parameters coupling system changes the modeling, identification and error compensation of geometric pa-rameters in the general kinematic calibration into those of linear combinations of parameters. By using the four theorems of the MLCs, the sets of the MLCs that are respectively related to the relative precision and absolute precision are determined. All simple and feasible measurement methods in practice are given, and identifica-tion analysis of the set of the MLCs for each measurement is carried out. According to the identification analysis results, a step calibration including step measurement, step identification and step error compensation is determined by taking into ac-count both measurement costs and observability. The experiment shows that the proposed method has the following merits: (1) the parameter errors that cannot influence precision are completely avoided; (2) it reflects the mapping of linear combinations of parameters more accurately and enhances the precision of identi-fication; and (3) the method is robust, efficient and effective, so that the errors in position and orientation are kept at the same order of the measurement noise. Due to these merits, the present method is attractive for the 3-DOF planar parallel ki-nematic machine tool and can be also applied to other parallel kinematic machine tools with weakly nonlinear kinematics.

  4. Step kinematic calibration of a 3-DOF planar parallel kinematic machine tool

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    This paper presents a novel step kinematic calibration method for a 3 degree-of-freedom(DOF) planar parallel kinematic machine tool,based on the minimal linear combinations(MLCs) of error parameters.The method using mapping of linear combinations of parameters in error transfer multi-parameters coupling system changes the modeling,identification and error compensation of geometric parameters in the general kinematic calibration into those of linear combinations of parameters.By using the four theorems of the MLCs,the sets of the MLCs that are respectively related to the relative precision and absolute precision are determined.All simple and feasible measurement methods in practice are given,and identification analysis of the set of the MLCs for each measurement is carried out.According to the identification analysis results,a step calibration including step measurement,step identification and step error compensation is determined by taking into account both measurement costs and observability.The experiment shows that the proposed method has the following merits:(1) the parameter errors that cannot influence precision are completely avoided;(2) it reflects the mapping of linear combinations of parameters more accurately and enhances the precision of identification;and(3) the method is robust,efficient and effective,so that the errors in position and orientation are kept at the same order of the measurement noise.Due to these merits,the present method is attractive for the 3-DOF planar parallel kinematic machine tool and can be also applied to other parallel kinematic machine tools with weakly nonlinear kinematics.

  5. A machine learning tool for re-planning and adaptive RT: A multicenter cohort investigation.

    Science.gov (United States)

    Guidi, G; Maffei, N; Meduri, B; D'Angelo, E; Mistretta, G M; Ceroni, P; Ciarmatori, A; Bernabei, A; Maggi, S; Cardinali, M; Morabito, V E; Rosica, F; Malara, S; Savini, A; Orlandi, G; D'Ugo, C; Bunkheila, F; Bono, M; Lappi, S; Blasi, C; Lohr, F; Costi, T

    2016-12-01

    To predict patients who would benefit from adaptive radiotherapy (ART) and re-planning intervention based on machine learning from anatomical and dosimetric variations in a retrospective dataset. 90 patients (pts) treated for head-neck cancer (H&N) formed a multicenter data-set. 41 H&N pts (45.6%) were considered for learning; 49 pts (54.4%) were used to test the tool. A homemade machine-learning classifier was developed to analyze volume and dose variations of parotid glands (PG). Using deformable image registration (DIR) and GPU, patients' conditions were analyzed automatically. Support Vector Machines (SVM) was used for time-series evaluation. "Inadequate" class identified patients that might benefit from replanning. Double-blind evaluation by two radiation oncologists (ROs) was carried out to validate day/week selected for re-planning by the classifier. The cohort was affected by PG mean reduction of 23.7±8.8%. During the first 3weeks, 86.7% cases show PG deformation aligned with predefined tolerance, thus not requiring re-planning. From 4th week, an increased number of pts would potentially benefit from re-planning: a mean of 58% of cases, with an inter-center variability of 8.3%, showed "inadequate" conditions. 11% of cases showed "bias" due to DIR and script failure; 6% showed "warning" output due to potential positioning issues. Comparing re-planning suggested by tool with recommended by ROs, the 4th week seems the most favorable time in 70% cases. SVM and decision-making tool was applied to overcome ART challenges. Pts would benefit from ART and ideal time for re-planning intervention was identified in this retrospective analysis. Copyright © 2016 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  6. INVESTIGATION AND ASSESSMENT OF OCCUPATIONAL RISK ON THE METAL CUTTING MACHINE TOOL STAN

    Directory of Open Access Journals (Sweden)

    Jerzy Józwik

    2013-12-01

    Full Text Available The paper analyzes occupational risk at selected metal cutting machine tool stands (turning, milling, drilling and grinding stands and presents a set of recommendations formulated to minimize hazards at the above mentioned stands. The assessment is based on the analysis that allowed for selecting the best method of occupational risk assessment, measurements, observations, interviews and conclusions drawn from the obtained results. Occupational risk assessment forms were devised, what allowed for selecting appropriate action to increase the safety of selected machinery operators. The guidelines were assessed in terms of their practical implementation and expected utilitarian results.

  7. Heuristic algorithms for solving of the tool routing problem for CNC cutting machines

    Science.gov (United States)

    Chentsov, P. A.; Petunin, A. A.; Sesekin, A. N.; Shipacheva, E. N.; Sholohov, A. E.

    2015-11-01

    The article is devoted to the problem of minimizing the path of the cutting tool to shape cutting machines began. This problem can be interpreted as a generalized traveling salesman problem. Earlier version of the dynamic programming method to solve this problem was developed. Unfortunately, this method allows to process an amount not exceeding thirty circuits. In this regard, the task of constructing quasi-optimal route becomes relevant. In this paper we propose options for quasi-optimal greedy algorithms. Comparison of the results of exact and approximate algorithms is given.

  8. Apparatus for correcting precision errors in slide straigntness in machine tools

    Science.gov (United States)

    Robinson, S.C.; Gerth, H.L.

    The present invention is directed to a mechanism by which small deviations in slideway straightness and roll of a precision machining apparatus may be compensated for. The mechanism of the present invention comprises a fixture support disposed between the slideway carriage and the tool or workpiece fixture and provided with a hinge-like coupling between the carriage and the fixture support so as to allow for the minute and precise displacement of the fixture support in a direction normal to the direction of the slide path soa as to readily compensate for slight deviations in the straightness and roll of the slide path.

  9. Error compensation on precision machine tool servo control system based on digital concave filter

    Institute of Scientific and Technical Information of China (English)

    王立松; 苏宝库; 张晶; 董申

    2001-01-01

    It is concluded from the results of testing the frequency characteristics of the sub-micron precision machine tool servo control system, that the existence of several oscillating modalities is the main factor that affects the performance of the control system. To compensate for this effect, several concave filters are utilized in the system to improve the control accuracy. The feasibility of compensating for several oscillating modalities with a single concave filter is also studied. By applying a modified Butterworth concave filter to the practical system, the maximum stable state output error remains under + 10 nm in the closed-loop positioning system.

  10. Nonlinearity for a parallel kinematic machine tool and its application to interpolation accuracy analysis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    This paper is concerned with the kinematic nonlinearity measure of parallel kinematic machine tool (PKM),which depends upon differential geometry curvature.The nonlinearity can be described by the curve of the solution locus and the equal interval input of joints mapping into inequable interval output of the end-effectors.Such curing and inequation can be measured by BW curvature.So the curvature can measure the nonlinearity of PKM indirectly.Then the distribution of BW curvature in the local area and the whole workspace are also discussed.An example of application to the interpolation accuracy analysis of PKM is given to illustrate the effectiveness of this approach.

  11. The effects of vibration-reducing gloves on finger vibration.

    Science.gov (United States)

    Welcome, Daniel E; Dong, Ren G; Xu, Xueyan S; Warren, Christopher; McDowell, Thomas W

    2014-01-01

    Vibration-reducing (VR) gloves have been used to reduce the hand-transmitted vibration exposures from machines and powered hand tools but their effectiveness remains unclear, especially for finger protection. The objectives of this study are to determine whether VR gloves can attenuate the vibration transmitted to the fingers and to enhance the understanding of the mechanisms of how these gloves work. Seven adult male subjects participated in the experiment. The fixed factors evaluated include hand force (four levels), glove condition (gel-filled, air bladder, no gloves), and location of the finger vibration measurement. A 3-D laser vibrometer was used to measure the vibrations on the fingers with and without wearing a glove on a 3-D hand-arm vibration test system. This study finds that the effect of VR gloves on the finger vibration depends on not only the gloves but also their influence on the distribution of the finger contact stiffness and the grip effort. As a result, the gloves increase the vibration in the fingertip area but marginally reduce the vibration in the proximal area at some frequencies below 100 Hz. On average, the gloves reduce the vibration of the entire fingers by less than 3% at frequencies below 80 Hz but increase at frequencies from 80 to 400 Hz. At higher frequencies, the gel-filled glove is more effective at reducing the finger vibration than the air bladder-filled glove. The implications of these findings are discussed.

  12. 高性能组合机床和高生产率加工中心%The High Performance Combination Machine Tools and High Productivity Machining Center

    Institute of Scientific and Technical Information of China (English)

    卫美红; 张曙

    2014-01-01

    以汽车关键零部件制造为例,分析了机械制造业中高效率与高柔性之间的矛盾和统一。介绍了国际上高性能组合机床及高生产率加工中心的应用和技术发展趋势,并指出将数控技术引入专用机床是化解这对矛盾的正确方向。%Taking the car'parts and components manufacturing as examples , it analyzes the contradiction and uni-ty between high efficient and flexible in machinery manufacture , introduces the application and development trend of international high performance combination machine tools and high productivity machining center , sug-gests basic strategy to introduce the numerical control technology into specialized machine tools .

  13. High Accuracy On-line Measurement Method of Motion Error on Machine Tools Straight-going Parts

    Institute of Scientific and Technical Information of China (English)

    苏恒; 洪迈生; 魏元雷; 李自军

    2003-01-01

    Harmonic suppression, non-periodic and non-closing in straightness profile error that will bring about harmonic component distortion in measurement result are analyzed. The countermeasure-a novel accurate two-probe method in time domain is put forward to measure straight-going component motion error in machine tools based on the frequency domain 3-point method after symmetrical continuation of probes' primitive signal. Both straight-going component motion error in machine tools and the profile error in workpiece that is manufactured on this machine can be measured at the same time. The information is available to diagnose the fault origin of machine tools. The analysis result is proved to be correct by the experiment.

  14. Study of geometric errors detection method for NC machine tools based on non-contact circular track

    Science.gov (United States)

    Yan, Kejun; Liu, Jun; Gao, Feng; Wang, Huan

    2008-12-01

    This paper presents a non-contact measuring method of geometric errors for NC machine tools based on circular track testing method. Let the machine spindle move along a circular path, the position error of every tested position in the circle can be obtained using two laser interferometers. With a volumetric error model, the 12 components of geometric error apart from angular error components can be derived. It has characteristics of wide detection range and high precision. Being obtained geometric errors respectively, it is of great significance for the error compensation of NC machine tools. This method has been tested on a MCV-510 NC machine tool. The experiment result has been proved to be feasible for this method.

  15. Kinematic Modelling and Control Simulation for 1PS+3TPS Type Hybrid Machine Tool

    Institute of Scientific and Technical Information of China (English)

    FAN Shouwen; WANG Xiaobing; HUANG Hongzhong

    2006-01-01

    A structure scheme for a novel hybrid machine tool (HMT) is proposed in this paper. In the scheme, a 4-DOFs 1PS+3TPS type spatial hybrid mechanism is utilized as main feed mechanism, with assistance of a two direction movable worktable, multi-coordinates NC machining can be realized. In the main feed mechanism, fixed platform is connected with moving platform by three TPS driving links and one PS driving link, one translation DOF and three rotation DOFs can be achieved by it. This type HMT enjoys some advantages over its conventional counterparts:large workspace,good dexterity,etc. Closed form inverse displacement analysis model and inverse kinematic model for main feed mechanism are established. A fuzzy PID control scheme for machining control of HMTs with high tracking precision is proposed aiming at highly nonlinear, tightly coupled and uncertain characteristic of HMTs. Simulation researches for fuzzy PID control of HMTs are carried out. Simulation Results demonstrate the effectiveness and the Robostness of the fuzzy PID controller.

  16. Modeling of the flow stress for AISI H13 Tool Steel during Hard Machining Processes

    Science.gov (United States)

    Umbrello, Domenico; Rizzuti, Stefania; Outeiro, José C.; Shivpuri, Rajiv

    2007-04-01

    In general, the flow stress models used in computer simulation of machining processes are a function of effective strain, effective strain rate and temperature developed during the cutting process. However, these models do not adequately describe the material behavior in hard machining, where a range of material hardness between 45 and 60 HRC are used. Thus, depending on the specific material hardness different material models must be used in modeling the cutting process. This paper describes the development of a hardness-based flow stress and fracture models for the AISI H13 tool steel, which can be applied for range of material hardness mentioned above. These models were implemented in a non-isothermal viscoplastic numerical model to simulate the machining process for AISI H13 with various hardness values and applying different cutting regime parameters. Predicted results are validated by comparing them with experimental results found in the literature. They are found to predict reasonably well the cutting forces as well as the change in chip morphology from continuous to segmented chip as the material hardness change.

  17. Qualitative: Open Source Python Tool for Quality Estimation over Multiple Machine Translation Outputs

    Directory of Open Access Journals (Sweden)

    Eleftherios Avramidis

    2014-09-01

    Full Text Available “Qualitative” is a python toolkit for ranking and selection of sentence-level output by different MT systems using Quality Estimation. The toolkit implements a basic pipeline for annotating the given sentences with black-box features. Consequently, it applies a machine learning mechanism in order to rank data based on models pre-trained on human preferences. The preprocessing pipeline includes support for language models, PCFG parsing, language checking tools and various other pre-processors and feature generators. The code follows the principles of object-oriented programming to allow modularity and extensibility. The tool can operate by processing both batch-files and single sentences. An XML-RPC interface is provided for hooking up with web-services and a graphical animated web-based interface demonstrates its potential on-line use.

  18. Temperature variable optimization for precision machine tool thermal error compensation on optimal threshold

    Science.gov (United States)

    Zhang, Ting; Ye, Wenhua; Liang, Ruijun; Lou, Peihuang; Yang, Xiaolan

    2013-01-01

    Machine tool thermal error is an important reason for poor machining accuracy. Thermal error compensation is a primary technology in accuracy control. To build thermal error model, temperature variables are needed to be divided into several groups on an appropriate threshold. Currently, group threshold value is mainly determined by researchers experience. Few studies focus on group threshold in temperature variable grouping. Since the threshold is important in error compensation, this paper arms to find out an optimal threshold to realize temperature variable optimization in thermal error modeling. Firstly, correlation coefficient is used to express membership grade of temperature variables, and the theory of fuzzy transitive closure is applied to obtain relational matrix of temperature variables. Concepts as compact degree and separable degree are introduced. Then evaluation model of temperature variable clustering is built. The optimal threshold and the best temperature variable clustering can be obtained by setting the maximum value of evaluation model as the objective. Finally, correlation coefficients between temperature variables and thermal error are calculated in order to find out optimum temperature variables for thermal error modeling. An experiment is conducted on a precise horizontal machining center. In experiment, three displacement sensors are used to measure spindle thermal error and twenty-nine temperature sensors are utilized to detect the machining center temperature. Experimental result shows that the new method of temperature variable optimization on optimal threshold successfully worked out a best threshold value interval and chose seven temperature variables from twenty-nine temperature measuring points. The model residual of z direction is within 3 μm. Obviously, the proposed new variable optimization method has simple computing process and good modeling accuracy, which is quite fit for thermal error compensation.

  19. New method for computer numerical control machine tool calibration: Relay method

    Institute of Scientific and Technical Information of China (English)

    LIU Huanlao; SHI Hanming; LI Bin; ZHOU Huichen

    2007-01-01

    Relay measurement method,which uses the kilogram-meter (KGM) measurement system to identify volumetric errors on the planes of computer numerical con trol (CNC) machine tools,is verified through experimental tests.During the process,all position errors on the entire plane table are measured by the equipment,which is limited to a small field.All errors are obtained first by measuring the error of the basic position near the original point.On the basis of that positional error,the positional errors far away from the original point are measured.Using this analogy,the error information on the positional points on the entire plane can be obtained.The process outlined above is called the relay meth od.Test results indicate that the accuracy and repeatability are high,and the method can be used to calibrate geometric errors on the plane of CNC machine tools after backlash errors have been well compensated.

  20. Surface Roughness Prediction Model in Machining of Carbon Steel by PVD Coated Cutting Tools

    Directory of Open Access Journals (Sweden)

    Yusuf Sahin

    2004-01-01

    Full Text Available The surface roughness model in the turning of AISI 1040 carbon steel was developed in terms of cutting speed, feed rate and depth of cut using response surface methodology. Machining tests were carried out using PVD-coated tools under different cutting conditions. The surface roughness equations of cutting tools when machining the carbon steels were achieved by using the experimental data. The results are presented in terms of mean values and confidence levels. The established equation shows that the feed rate was found to be a main influencing factor on the surface roughness. It increased with increasing the feed rate, but decreased with increasing the cutting speed and the depth of cut, respectively. The variance analysis for the second-order model shows that the interaction terms and the square terms were statically insignificant. However, it could be seen that the first-order effect of feed rate was significant while cutting speed and depth of cut was insignificant. The predicted surface roughness of the samples was found to lie close to that of the experimentally observed ones with 95% confident intervals.

  1. Third-order point contact approach for five-axis sculptured surface machining using non-ball-end tools(II): Tool positioning strategy

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Based on the mathematical model describing the third-order approximation of the cutter envelope surface according to one given cutter location(CL),a tool positioning strategy is proposed for efficiently machining free-form surfaces with non-ball-end cutters.The optimal CL is obtained by adjusting the inclination and tilt angles of the cutter until its envelope surface and the design surface have the third-order contact at the cutter contact(CC)point,which results in a wide machining strip.The strategy can handle the constraints of machine joint angle limits,global collision avoidance and tool path smoothness in a nature way,and can be applied to general rotary cutters and complex surfaces.Numerical examples demonstrate that the third-order point contact approach can improve the machining strip width greatly as compared with the recently reported second-order one.

  2. Micro-Vibration Performance Prediction of SEPTA24 Using SMeSim (RUAG Space Mechanism Simulator Tool)

    Science.gov (United States)

    Omiciuolo, Manolo; Lang, Andreas; Wismer, Stefan; Barth, Stephan; Szekely, Gerhard

    2013-09-01

    Scientific space missions are currently challenging the performances of their payloads. The performances can be dramatically restricted by micro-vibration loads generated by any moving parts of the satellites, thus by Solar Array Drive Assemblies too. Micro-vibration prediction of SADAs is therefore very important to support their design and optimization in the early stages of a programme. The Space Mechanism Simulator (SMeSim) tool, developed by RUAG, enhances the capability of analysing the micro-vibration emissivity of a Solar Array Drive Assembly (SADA) under a specified set of boundary conditions. The tool is developed in the Matlab/Simulink® environment throughout a library of blocks simulating the different components a SADA is made of. The modular architecture of the blocks, assembled by the user, and the set up of the boundary conditions allow time-domain and frequency-domain analyses of a rigid multi-body model with concentrated flexibilities and coupled- electronic control of the mechanism. SMeSim is used to model the SEPTA24 Solar Array Drive Mechanism and predict its micro-vibration emissivity. SMeSim and the return of experience earned throughout its development and use can now support activities like verification by analysis of micro-vibration emissivity requirements and/or design optimization to minimize the micro- vibration emissivity of a SADA.

  3. Machine Tool Advanced Skills Technology (MAST). Common Ground: Toward a Standards-Based Training System for the U.S. Machine Tool and Metal Related Industries. Volume 13: Laser Machining, of a 15-Volume Set of Skill Standards and Curriculum Training Materials for the Precision Manufacturing Industry.

    Science.gov (United States)

    Texas State Technical Coll., Waco.

    This document is intended to help education and training institutions deliver the Machine Tool Advanced Skills Technology (MAST) curriculum to a variety of individuals and organizations. MAST consists of industry-specific skill standards and model curricula for 15 occupational specialty areas within the U.S. machine tool and metals-related…

  4. Transformation design of drilling machine by variable speed and vibration reduction%变速振动减振钻床的改造设计

    Institute of Scientific and Technical Information of China (English)

    王道林

    2013-01-01

    According to the analysis of the causes for the problems of the drilling quality, by using variable speed cutting technology and advanced theory of vibration drilling, an vibration reduction drilling machine by variable speed was developed. The experimental result shows that the new drilling machine can greatly improve the hole processing quality.%依据钻孔质量问题产生原因的分析,利用变速切削技术和振动钻削理论,设计了一种变速振动减振钻床.实践证明,采用该钻床加工,可以大大提高孔的加工质量.

  5. An atomistic investigation on the mechanism of machining nanostructures when using single tip and multi-tip diamond tools

    Energy Technology Data Exchange (ETDEWEB)

    Tong, Zhen [Department of Design, Manufacture and Engineering Management, University of Strathclyde, Glasgow G1 1XQ (United Kingdom); Centre for Precision Technologies, University of Huddersfield, Huddersfield HD1 3DH (United Kingdom); Center for Precision Engineering, Harbin Institute of Technology, Harbin 150001 (China); Liang, Yingchun [Center for Precision Engineering, Harbin Institute of Technology, Harbin 150001 (China); Jiang, Xiangqian [Centre for Precision Technologies, University of Huddersfield, Huddersfield HD1 3DH (United Kingdom); Luo, Xichun, E-mail: xichun.luo@strath.ac.uk [Department of Design, Manufacture and Engineering Management, University of Strathclyde, Glasgow G1 1XQ (United Kingdom); Centre for Precision Technologies, University of Huddersfield, Huddersfield HD1 3DH (United Kingdom)

    2014-01-30

    In our previous work, a scale-up fabrication approach to cost effectively manufacturing nano-gratings over large area has been developed through diamond turning by using a multi-tip diamond tool fabricated by Focused Ion Beam. The objective of this study is to gain an in-depth understanding of the mechanism of machining nanostructures on single crystal copper through diamond turning when using a single tip and a multi-tip nanoscale diamond tool. For this purpose atomistic models of a single tip tool for multi-pass cutting and a multi-tip tool for single-pass cutting were built, respectively. The nature of the cutting chip formation, dislocation nucleation and propagation, cutting forces, and temperature distribution during nanometric cutting processes were studied through molecular dynamics (MD) simulations. Results show that nanostructure generation process at steady cutting stage was governed by a strong localization of the dislocation movement and the dynamic equilibrium of chip-tool contact area. Except the apparent improvement of machining efficiency that proportional to the tool tip numbers, the nano-grooves generated by multi-tip tool also have higher center symmetry than those machined by single tip tool. While the average tangential cutting force per tip were calculated all around 33.3 nN, a larger normal cutting force per tip being 54.1 nN was observed when using a multi-tip tool. A concept of atomistic equivalent temperature was proposed and used to analysis the important features of temperature distribution during the machining process. The advantage, disadvantage and applicability of diamond turning using multi-tip tool were discussed in comparison with those of using single-tip tool. The findings suggest that diamond turning using multi-tip tool might be more applicable than using single tip tool when apply to scale-up fabrication of periodic nanostructures.

  6. EFFECT OF TOOL POLARITY ON THE MACHINING CHARACTERISTICS IN ELECTRIC DISCHARGE MACHINING OF SILVER STEEL AND STATISTICAL MODELLING OF THE PROCESS

    Directory of Open Access Journals (Sweden)

    DILSHAD AHMAD KHAN,

    2011-06-01

    Full Text Available Electric discharge machining (EDM is a thermoelectric process in which electrical energy is converted into thermal energy and this thermal energy is used for the machining purpose. It is the common practice in EDM to make tool negative and work piece positive (direct polarity , but researches shows that reverse of it is also possible in which tool is positive and work piece is negative ( reverse polarity, but not much work has been carried out on the reverse polarity till now. This paper discusses the effect of tool polarity on the machining characteristics in electric discharge machining of silver steel. High metal removal rate, low relative electrode wear and good surface finish are conflicting goals, which can not be achieved simultaneously with a particular combination of control settings. To achieve the best machining results, the goal has to be taken separately in different phases of work with different emphasis. A 32 factorial design has been used for planning of experimental conditions. Copper is used as tool material and Silver steel of 28 grade is selected as work piece material with positive and negative polarities. The effectiveness of EDM process with silver steel is evaluated in terms of metal removal rate (MRR, percent relative electrode wear (%REW and the surface roughness (S.R ofthe work piece produced at different current and pulse duration levels. In this experimental work spark erosion oil (trade name IPOL is taken as a dielectric and experiments have been conducted at 50% duty factor. The study reveals that direct polarity is suitable for higher metal removal rate and lower relative electrode wear but reverse polarity gives better surface finish as compared to direct polarity. Direct polarity gives 4-11 times more MRR and 5 times less relative electrode wear as compared to reverse polarity, and reverse polarity gives 1.3-2.7 times better surface finish as compared to direct polarity. Second order regression model is also

  7. Role of the Whole Body Vibration Machine in the Prevention and Management of Osteoporosis in Old Age: A Systematic Review

    Science.gov (United States)

    Swe, Myint; Benjamin, Biju; Tun, Aye Aye; Sugathan, Sandheep

    2016-01-01

    A literature search of related articles was carried out in electronic data sources. Initially, 276 randomised controlled trials related to the title were collected, after which 44 were selected using the keywords. Overlapping articles, articles with a study duration of less than six months, and studies involving young participants were removed from the list. The remaining 20 articles were checked for entitlement using the PEDro scale. A total of nine eligible articles with 1486 participants were analysed. Seven trials used dual-energy x-ray absorptiometry (DXA) to measure bone mineral density (BMD). The six trials published from 2005 to 2013 found a significant increase in BMD. In the remaining one trial, there was no significant increase in BMD. One study published in 2013 reported a significant increase in BMD measured with peripheral qualitative computed tomography, whereas another trial published in 2014 stated that there was a reduction in calcaneal bone density measured by peripheral qualitative ultrasound. From these findings it can be concluded that the whole body vibration machine is a good adjunctive therapy for the prevention and management of osteoporosis in postmenopausal women. However, further investigations are necessary before the same can be recommended for elderly men. PMID:27904420

  8. Optimization of process parameters on EN24 Tool steel using Taguchi technique in Electro-Discharge Machining (EDM)

    Science.gov (United States)

    Jeykrishnan, J.; Vijaya Ramnath, B.; Akilesh, S.; Pradeep Kumar, R. P.

    2016-09-01

    In the field of manufacturing sectors, electric discharge machining (EDM) is widely used because of its unique machining characteristics and high meticulousness which can't be done by other traditional machines. The purpose of this paper is to analyse the optimum machining parameter, to curtail the machining time with respect to high material removal rate (MRR) and low tool wear rate (TWR) by varying the parameters like current, pulse on time (Ton) and pulse off time (Toff). By conducting several dry runs using Taguchi technique of L9 orthogonal array (OA), optimized parameters were found using analysis of variance (ANOVA) and the error percentage can be validated and parameter contribution for MRR and TWR were found.

  9. Effect of High-speed Milling tool path strategies on the surface roughness of Stavax ESR mold insert machining

    Science.gov (United States)

    Mebrahitom, A.; Rizuan, D.; Azmir, M.; Nassif, M.

    2016-02-01

    High speed milling is one of the recent technologies used to produce mould inserts due to the need for high surface finish. It is a faster machining process where it uses a small side step and a small down step combined with very high spindle speed and feed rate. In order to effectively use the HSM capabilities, optimizing the tool path strategies and machining parameters is an important issue. In this paper, six different tool path strategies have been investigated on the surface finish and machining time of a rectangular cavities of ESR Stavax material. CAD/CAM application of CATIA V5 machining module for pocket milling of the cavities was used for process planning.

  10. Micro Hole Machining Experimental Study of Ultrasonic Elliptical Vibration Boring%微孔椭圆超声镗削加工实验研究

    Institute of Scientific and Technical Information of China (English)

    马协力; 张德远; 王冠

    2014-01-01

    Ultrasonic elliptical vibration micro-hole boring method is successfully applied to precision cutting due to its superior performances, such as low average cutting force and high machining precision. The theory of micro-hole boring machining and ultrasonic elliptical vibration micro-hole boring is analyzed to give fully play to the advantage of ultrasonic elliptical vibration for the problem of aviation engine fuel nozzles micro fabrication. The vibration amplitude contrast experiment proves that the ultrasonic vibration micro hole boring method has the advantages of low average cutting force and high surface quality compared with the traditional micro boring method. The micro hole ultrasonic elliptical boring is an effective method for micro hole machining.%微孔镗削加工采用椭圆超声技术具有降低切削力和改善表面加工质量的优势。为了充分发挥椭圆超声技术的优势,针对航空发动机燃油喷嘴精细加工的难题,分析了微孔镗削微细加工和微孔椭圆超声镗削的加工机理,通过振动振幅对比实验验证了微孔椭圆超声镗削加工比普通镗削加工更具有降低切削力和提高表面加工质量的能力。微孔椭圆超声振动加工为发动机燃油喷嘴的精细加工提供了一条有效途径。

  11. 振动辅助切削加工技术研究现状%Research status of the vibration assisted machining (VAM)technology

    Institute of Scientific and Technical Information of China (English)

    李增强; 喻栋; 孙涛

    2015-01-01

    随着精密与超精密加工技术的不断发展和成熟,将振动辅助切削技术应用到精密与超精密加工中去已成为发展的一个必然趋势。结合国内外研究人员的研究成果,介绍了超声振动辅助切削技术的基本原理,综述了超声振动辅助切削技术的优势以及研究现状。%With the constantly development of precision and ultra-precision machining technology,the vibration assisted machining (VAM)technology applied to the precision and ultra-precision machining has become an inev-itable trend.This paper combines the domestic and foreign researchers’achievements and introduces the basic principle of ultrasonic vibration assisted cutting technology.Finally,the advantages and research status of the ul-trasonic vibration assisted cutting technology is summarized at the end of paper.

  12. VIBRATIONS DETECTION IN INDUSTRIAL PUMPS BASED ON SPECTRAL ANALYSIS TO INCREASE THEIR EFFICIENCY

    Directory of Open Access Journals (Sweden)

    Belhadef RACHID

    2016-01-01

    Full Text Available Spectral analysis is the key tool for the study of vibration signals in rotating machinery. In this work, the vibration analy-sis applied for conditional preventive maintenance of such machines is proposed, as part of resolved problems related to vibration detection on the organs of these machines. The vibration signal of a centrifugal pump was treated to mount the benefits of the approach proposed. The obtained results present the signal estimation of a pump vibration using Fourier transform technique compared by the spectral analysis methods based on Prony approach.

  13. Evaluation of machine learning tools for inspection of steam generator tube structures using pulsed eddy current

    Science.gov (United States)

    Buck, J. A.; Underhill, P. R.; Morelli, J.; Krause, T. W.

    2017-02-01

    Degradation of nuclear steam generator (SG) tubes and support structures can result in a loss of reactor efficiency. Regular in-service inspection, by conventional eddy current testing (ECT), permits detection of cracks, measurement of wall loss, and identification of other SG tube degradation modes. However, ECT is challenged by overlapping degradation modes such as might occur for SG tube fretting accompanied by tube off-set within a corroding ferromagnetic support structure. Pulsed eddy current (PEC) is an emerging technology examined here for inspection of Alloy-800 SG tubes and associated carbon steel drilled support structures. Support structure hole size was varied to simulate uniform corrosion, while SG tube was off-set relative to hole axis. PEC measurements were performed using a single driver with an 8 pick-up coil configuration in the presence of flat-bottom rectangular frets as an overlapping degradation mode. A modified principal component analysis (MPCA) was performed on the time-voltage data in order to reduce data dimensionality. The MPCA scores were then used to train a support vector machine (SVM) that simultaneously targeted four independent parameters associated with; support structure hole size, tube off-centering in two dimensions and fret depth. The support vector machine was trained, tested, and validated on experimental data. Results were compared with a previously developed artificial neural network (ANN) trained on the same data. Estimates of tube position showed comparable results between the two machine learning tools. However, the ANN produced better estimates of hole inner diameter and fret depth. The better results from ANN analysis was attributed to challenges associated with the SVM when non-constant variance is present in the data.

  14. A field study investigating the effects of a rebar-tying machine on trunk flexion, tool usability and productivity.

    Science.gov (United States)

    Vi, Peter

    2006-11-15

    A field study with a before-and-after experimental design was conducted to evaluate the potential reduction in the risk of musculoskeletal injuries to rodworkers when using an automatic rebar-tying machine. Eleven rodworkers participated in this experiment. All dependent variables (trunk posture, rebar-tying time and responses to a usability questionnaire) were first measured before introducing the rebar-tying machine and then after 3 months of usage all dependent variables were measured again. The results of the study indicated that working with a rebar-tying machine significantly reduced the magnitude, frequency and duration of exposure to awkward trunk posture. Tying time was reduced when participants used the machine. The usability questionnaire indicated that most participants preferred to use the rebar-tying machine for ground-level rebar construction. The field study also revealed that the rebar-tying machine is not limited to the reinforcing trade. The machine can be used for other purposes, such as tying electrical conduit and attaching radiant heat tube to steel mesh. Based on trunk posture exposure, rebar-tying time, usability and transferability, it is concluded that the rebar-tying machine can be an effective tool to reduce the frequency and duration of severe trunk flexion, improve usability and increase productivity among concrete reinforcement workers.

  15. Feed drive modelling for the simulation of tool path tracking in multi-axis High Speed Machining

    CERN Document Server

    Prévost, David; Lartigue, Claire; Dumur, Didier

    2011-01-01

    Within the context of High Speed Machining, it is essential to manage the trajectory generation to achieve both high surface quality and high productivity. As feed drives are one part of the set Machine tool - Numerical Controller, it is necessary to improve their performances to optimize feed drive dynamics during trajectory follow up. Hence, this paper deals with the modelling of the feed drive in the case of multi axis machining. This model can be used for the simulation of axis dynamics and tool-path tracking to tune parameters and optimize new frameworks of command strategies. A procedure of identification based on modern NC capabilities is presented and applied to industrial HSM centres. Efficiency of this modelling is assessed by experimental verifications on various representative trajectories. After implementing a Generalized Predictive Control, reliable simulations are performed thanks to the model. These simulations can then be used to tune parameters of this new framework according to the tool-pat...

  16. Wear resistance of machine tools' bionic linear rolling guides by laser cladding

    Science.gov (United States)

    Wang, Yiqiang; Liu, Botao; Guo, Zhengcai

    2017-06-01

    In order to improve the rolling wear resistance (RWR) of linear rolling guides (LRG) as well as prolong the life of machine tools, various shape samples with different units spaces ranged from 1 to 5 mm are designed through the observation of animals in the desert and manufactured by laser cladding. Wear resistance tests reproducing closely the real operational condition are conducted by using a homemade linear reciprocating wear test machine, and wear resistance is evaluated by means of weight loss measurement. Results indicate that the samples with bionic units have better RWR than the untreated one, of which the reticulate treated sample with unit space 3 mm present the best RWR. More specifically, among the punctuate treated samples, the mass loss increases with the increase of unit space; among the striate treated samples, the mass loss changes slightly with the increase of unit space, attaining a minimum at the unit space of 4 mm; among the reticulate treated samples, with the increase of unit space, the mass loss initially decreases, but turns to increase after reaching a minimum at the unit space of 3 mm. Additionally, the samples with striate shape perform better wear resistance than the other shape groups on the whole. From the ratio value of laser treated area to contacted area perspective, that the samples with ratio value between 0.15 and 0.3 possess better wear resistance is concluded.

  17. Structure Based Thermostability Prediction Models for Protein Single Point Mutations with Machine Learning Tools.

    Science.gov (United States)

    Jia, Lei; Yarlagadda, Ramya; Reed, Charles C

    2015-01-01

    Thermostability issue of protein point mutations is a common occurrence in protein engineering. An application which predicts the thermostability of mutants can be helpful for guiding decision making process in protein design via mutagenesis. An in silico point mutation scanning method is frequently used to find "hot spots" in proteins for focused mutagenesis. ProTherm (http://gibk26.bio.kyutech.ac.jp/jouhou/Protherm/protherm.html) is a public database that consists of thousands of protein mutants' experimentally measured thermostability. Two data sets based on two differently measured thermostability properties of protein single point mutations, namely the unfolding free energy change (ddG) and melting temperature change (dTm) were obtained from this database. Folding free energy change calculation from Rosetta, structural information of the point mutations as well as amino acid physical properties were obtained for building thermostability prediction models with informatics modeling tools. Five supervised machine learning methods (support vector machine, random forests, artificial neural network, naïve Bayes classifier, K nearest neighbor) and partial least squares regression are used for building the prediction models. Binary and ternary classifications as well as regression models were built and evaluated. Data set redundancy and balancing, the reverse mutations technique, feature selection, and comparison to other published methods were discussed. Rosetta calculated folding free energy change ranked as the most influential features in all prediction models. Other descriptors also made significant contributions to increasing the accuracy of the prediction models.

  18. Structure Based Thermostability Prediction Models for Protein Single Point Mutations with Machine Learning Tools.

    Directory of Open Access Journals (Sweden)

    Lei Jia

    Full Text Available Thermostability issue of protein point mutations is a common occurrence in protein engineering. An application which predicts the thermostability of mutants can be helpful for guiding decision making process in protein design via mutagenesis. An in silico point mutation scanning method is frequently used to find "hot spots" in proteins for focused mutagenesis. ProTherm (http://gibk26.bio.kyutech.ac.jp/jouhou/Protherm/protherm.html is a public database that consists of thousands of protein mutants' experimentally measured thermostability. Two data sets based on two differently measured thermostability properties of protein single point mutations, namely the unfolding free energy change (ddG and melting temperature change (dTm were obtained from this database. Folding free energy change calculation from Rosetta, structural information of the point mutations as well as amino acid physical properties were obtained for building thermostability prediction models with informatics modeling tools. Five supervised machine learning methods (support vector machine, random forests, artificial neural network, naïve Bayes classifier, K nearest neighbor and partial least squares regression are used for building the prediction models. Binary and ternary classifications as well as regression models were built and evaluated. Data set redundancy and balancing, the reverse mutations technique, feature selection, and comparison to other published methods were discussed. Rosetta calculated folding free energy change ranked as the most influential features in all prediction models. Other descriptors also made significant contributions to increasing the accuracy of the prediction models.

  19. Effect of tool material on machinability of TiCp reinforced Al-1100 composite

    Science.gov (United States)

    Harishchandra; Kadadevaramath, R. S.; Anil, K. C.

    2016-09-01

    In present days MMC's are widely used in most of the industries, like automobiles, aerospace, minerals and marine industries, because of its high specific strength to weight ratio. There are many types of reinforcements are available, selection of reinforcement is depends on availability, cost and desired reinforcement properties. In our study Al-1100 is selected as a primary material and Titanium carbide particle (TiCp) of 44 pm size as reinforcement and synthesized by manual stir casting method, by varying the reinforcement percentage. K2DF6 salt was used as wetting agent in order to improve the wetting behaviour of the reinforcement and same was observed in optical micrographs. Further, prepared composite materials are subjected to machinability studies by using lathe tool dynamometer in order to evaluate the cutting force, surface roughness with respect to reinforcement percentage and tool material. From the results, it is observed that the hardness and surface roughness of a specimen increases with the increasing of reinforcement percentage and Hardness of the tool material respectively.

  20. "A WAR OF MACHINERY”: the British Machine Tool Industry and Arming the Western Front, 1914-1916

    Directory of Open Access Journals (Sweden)

    Roger Lloyd-Jones

    2008-01-01

    Full Text Available According to David Lloyd George, Britain’s first Minister of Munitions, World War L “the Great War” was a “war of machinery,” and required unprecedented supplies of ammunition and the machine tools necessary to make them. In the early phase of the conflict, when the importance of machine tools was not fully recognized, a shortage of ammunition on the western front precipitated a military and political crisis, and led to the formation of the Ministry of Munitions. A trade-off between quantity and quality of ammunition shell (the machined outer metal casing was a product of the Ministry directive to increase output as both makers and users of machine tools came under intense pressure to reach their goals. British engineering achieved huge increases in ammunition output in preparation for the Somme offensive, but the complexities of the supply chain meant that makers and users of machine tools put them to use to make ammunition of a type and quality that was to prove defective.

  1. Swept Mechanism of Micro-Milling Tool Geometry Effect on Machined Oxygen Free High Conductivity Copper (OFHC) Surface Roughness.

    Science.gov (United States)

    Shi, Zhenyu; Liu, Zhanqiang; Li, Yuchao; Qiao, Yang

    2017-01-28

    Cutting tool geometry should be very much considered in micro-cutting because it has a significant effect on the topography and accuracy of the machined surface, particularly considering the uncut chip thickness is comparable to the cutting edge radius. The objective of this paper was to clarify the influence of the mechanism of the cutting tool geometry on the surface topography in the micro-milling process. Four different cutting tools including two two-fluted end milling tools with different helix angles of 15° and 30° cutting tools, as well as two three-fluted end milling tools with different helix angles of 15° and 30° were investigated by combining theoretical modeling analysis with experimental research. The tool geometry was mathematically modeled through coordinate translation and transformation to make all three cutting edges at the cutting tool tip into the same coordinate system. Swept mechanisms, minimum uncut chip thickness, and cutting tool run-out were considered on modeling surface roughness parameters (the height of surface roughness Rz and average surface roughness Ra) based on the established mathematical model. A set of cutting experiments was carried out using four different shaped cutting tools. It was found that the sweeping volume of the cutting tool increases with the decrease of both the cutting tool helix angle and the flute number. Great coarse machined surface roughness and more non-uniform surface topography are generated when the sweeping volume increases. The outcome of this research should bring about new methodologies for micro-end milling tool design and manufacturing. The machined surface roughness can be improved by appropriately selecting the tool geometrical parameters.

  2. Thermal Error Modeling of the CNC Machine Tool Based on Data Fusion Method of Kalman Filter

    Directory of Open Access Journals (Sweden)

    Haitong Wang

    2017-01-01

    Full Text Available This paper presents a modeling methodology for the thermal error of machine tool. The temperatures predicted by modified lumped-mass method and the temperatures measured by sensors are fused by the data fusion method of Kalman filter. The fused temperatures, instead of the measured temperatures used in traditional methods, are applied to predict the thermal error. The genetic algorithm is implemented to optimize the parameters in modified lumped-mass method and the covariances in Kalman filter. The simulations indicate that the proposed method performs much better compared with the traditional method of MRA, in terms of prediction accuracy and robustness under a variety of operating conditions. A compensation system is developed based on the controlling system of Siemens 840D. Validated by the compensation experiment, the thermal error after compensation has been reduced dramatically.

  3. Precision Measurement of Cylinder Surface Profile on an Ultra-Precision Machine Tool

    Science.gov (United States)

    Lee, J. C.; Noh, Y. J.; Arai, Y.; Gao, W.; Park, C. H.

    2009-01-01

    This paper describes the measurement of the surface straightness profile of a cylinder workpiece on an ultra-precision machine tool which has a T-base design with a spindle, an X-slide and a Z-slide. The movement range of the X-slide is 220 mm and that of the Z-slide is 150 mm, which have roller bearings in common. Two capacitive sensors are employed to scan a cylinder workpiece mounted on the spindle along the Z-axis. The straightness error motion of the Z-slide is measured to be approximately 100 nm by the reversal method. The straightness profile of the cylinder workpiece is evaluated to be approximately 400 nm by separation of the motion error, simultaneously.

  4. Sensorless compensation system for thermal deformations of ball screws in machine tools drives

    Science.gov (United States)

    Kowal, Michał

    2016-12-01

    The article presents constructional, technological and operational issues associated with the compensation of thermal deformations of ball screw drives. Further, it demonstrates the analysis of a new sensorless compensation method relying on coordinated computation of data fed directly from the drive and the control system in combination with the information pertaining to the operational history of the servo drive, retrieved with the use of an artificial neural networks (ANN)-based learning system. Preliminary ANN-based models, developed to simulate energy dissipation resulting from the friction in the screw-cap assembly and convection of heat are expounded upon, as are the processes of data selection and ANN learning. In conclusion, the article presents the results of simulation studies and preliminary experimental evidence confirming the applicability of the proposed method, efficiently compensating for the thermal elongation of the ball screw in machine tool drives.

  5. SKYNET: an efficient and robust neural network training tool for machine learning in astronomy

    CERN Document Server

    Graff, Philip; Hobson, Michael P; Lasenby, Anthony N

    2013-01-01

    We present the first public release of our generic neural network training algorithm, called SKYNET. This efficient and robust machine-learning tool is able to train large and deep feed-forward neural networks, including autoencoders, for use in a wide range of supervised and unsupervised learning applications, such as regression, classification, density estimation, clustering and dimensionality reduction. SKYNET uses a powerful 'pre-training' method, to obtain a set of network parameters close to the true global maximum of the training objective function, followed by further optimisation using an automatically-regularised variant of Newton's method; the latter uses second-order derivative information to improve convergence, but without the need to evaluate or store the full Hessian matrix, by using a fast approximate method to calculate Hessian-vector products. This combination of methods allows for the training of complicated networks that are difficult to optimise using standard backpropagation techniques....

  6. Machining of the Flat Surfaces with Abrasive-metallic Lapping Tools

    Institute of Scientific and Technical Information of China (English)

    Adam Barylski

    2004-01-01

    The constructional principle of abrasion metal disc is that abrasive insertions are spread uniformly on the working surface of a metal base. During lapping by means of such tools only the machining fluid is dosed and that by drop.Abrasive elements of circular shape pellets are produced by mixing boron carbide BC400 micrograins with electrographite components, the pellets were pressed with a load of about 12 kN. Next they were heated in furnace at about 520K for hours,then cooled together with the furnace. Tests were carried out on the making of circular abrasive insertions of which the main components were born carbide and micrograins of electric copper mixed the epoxide resins.

  7. Machining of the Flat Surfaces with Abrasive-metallic Lapping Tools

    Institute of Scientific and Technical Information of China (English)

    AdamBarylski

    2004-01-01

    The constructional principle of abrasion metal disc is that abrasive insertions are spread uniformly on the working surface of a metal base. During lapping by means of such tools only the machining fluid is dosed and that by drop. Abrasive elements of circular shape pellets are produced by mixing boron carbide BC400 micrograins with electrographite components, the pellets were pressed with a load of about 12 kN. Next they were heated in furnace at about 520K for hours, then cooled together with the furnace. Tests were carried out on the making of circular abrasive insertions of which the main components were born carbide and micrograins of electric copper mixed the epoxide resins.

  8. Factors discriminating inventory management performance: An exploratory study of Indian machine tool SMEs

    Directory of Open Access Journals (Sweden)

    Rajeev Narayana Pillai

    2014-06-01

    Full Text Available Purpose: There are many kinds of methods to evaluate the inventory management and economic performance of small and medium enterprises, but they still have some distinct shortcomings. In order to achieve a better evaluation result, we put forward a new model based on the evidences from developing country like India.Approach: This survey study, mainly based on the evidences from machine tool SMEs in India uses statistical methods to avoid the drawbacks of qualitative techniques.Findings: Through empirical data, it is established that ‘technology’ is not the only concern, but other factors related to human resource, economic, organizational and behavioral aspects of SMEs are also vital in improving their IM performance.Originality: This study combines the role of factors such as managerial, technological, economical and contingency together for the first time in the context of SMEs.

  9. APPLICATION OF SIMULTANEOUS FEEDBACK CONTROLLER FOR FREE AND FORCED ACTIVE VIBRATIONS CONTROL

    OpenAIRE

    Rachin Goyal*, Amresh Kumar, Manoj Kumar

    2016-01-01

    Evergrowing customer demands and thus the manufacturing methods have become the backbone of global competition for a wide range of products. This has led to the development of intelligent, compact and lightweight smart machine tools. A great difficulty is faced in the design of such machine tools due to the fact that the reduction in weight results in low rigidity and poor vibration control characteristics. The induced vibrations in the system may destabilize the system and result in complete...

  10. Rigidity FEA of cantilever of abrasive water jet machine tool based on ANSYS%基于ANSYS磨料水射流机床悬臂梁刚度的有限元分析

    Institute of Scientific and Technical Information of China (English)

    杜文正; 雷玉勇; 李劲松; 杨振; 郭逸伟

    2012-01-01

    目前二维半磨料水射流机床大多采用悬臂梁结构。悬臂梁是磨料水射流切割头及其附件的重要承载部件,其刚度直接影响机床的加工精度。针对磨料水射流机床的悬臂梁进行了三维建模,并基于ANSYS对其进行了模态和频率响应分析。分析的结果为磨料水射流机床的减振、防振提供了理论依据。%The cantilever structure was used in most abrasive water jet machine tools.The cantilever is an important component supporting the abrasive water jet cutting head as well as other accessories.Its rigidity directly affects the machining accuracy.A 3D model of the cantilever of the abrasive water jet machine tool was established,and modal analysis and frequency response analysis were carried out based on ANSYS.The analysis results offered theoretical references for vibration reduction and prevention of the abrasive water jet machine tool.

  11. Laser Machining Series. Educational Resources for the Machine Tool Industry. Course Syllabi, Instructor's Handbook, [and] Student Laboratory Manual.

    Science.gov (United States)

    Texas State Technical Coll. System, Waco.

    This package consists of course syllabi, an instructor's handbook, and a student laboratory manual for a 1-year vocational training program to prepare students for entry-level employment as laser machining technicians. The program was developed through a modification of the DACUM (Developing a Curriculum) technique. The course syllabi volume…

  12. Nonlinearity for a parallel kinematic machine tool and its application to interpolation accuracy analysis

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    [1]Carlo,I.,Direct Position Analysis of The Stewart Platform Mechanism,Mech.Mach.Theory,1990,25(6): 611-621.[2]Fitchter,E.F.,A Stewart platform based manipulator general theory and practical construction,Inter.Journal of Robtics Research,1986,(2): 157-182.[3]Raghavan,M.,The Stewart platform of general geometry has 40 configurations,ASME J.Mechanical Design,1993,115(2): 277-281.[4]Wampler,C.W.,Forward displacement analysis of general six-in-parallel SPS (Stewart) platform manipulators using SOMA Coordinates,Mech.Mach.Theory,1995,31(3): 331-337.[5]Wen,F.A.,Liang,C.G.,Displacement analysis of the 6-6 stewart platform mechanisms,Mech.Mach.Theory,1994,29(4): 547-557.[6]Liang,C.G.,Rong,H.,The forward displacement solution to a Stewart platform type maniputator,China Journal of Mechanical Engineering,1991,27(2): 26-30.[7]Huang,Z.,Spatial Mechanisms,Beijing: China Machine Press,1991.[8]Liu,K.et al.,The singularities and dynamics of a stewart platform manipulator,J.of Intelligent and Robotic Systems,1993,8: 287-308.[9]Bates,D.M.,Watts,D.G.,Relative curvature measures of nonlinearity,Journal of the Royal Statistical Society,1980(B42): 1-25.[10]Huang Tian,Wang Jinsong,Whitehouse,D.J.,Theory and methodology for kinematic design of Gough-Stewart platforms,Science in China,Series E,1999,42(4): 425-436.[11]Wang,Z.H.,Wang,J.S.,Yang,X.D.,Wei,Y.M.,Interpolation scheme and simulation study on its accuracy for a Stewart platform based CNC machine Tool VAMTIY,China Mechanical Engineering,1999,10(10): 1121-1123.[12]Wang Zhonghua,Wang Jinsong,Study on interpolation and its error distribution in workspace for a Stewart platform based CNC machine tool,in Proceedings of International Conference on Advanced Manufacturing Systems and Manufacturing Automation (AMSMA'2000),19th-2st,June,2000,Guangzhou,China.

  13. Gaussian Process Regression as a machine learning tool for predicting organic carbon from soil spectra - a machine learning comparison study

    Science.gov (United States)

    Schmidt, Andreas; Lausch, Angela; Vogel, Hans-Jörg

    2016-04-01

    Diffuse reflectance spectroscopy as a soil analytical tool is spreading more and more. There is a wide range of possible applications ranging from the point scale (e.g. simple soil samples, drill cores, vertical profile scans) through the field scale to the regional and even global scale (UAV, airborne and space borne instruments, soil reflectance databases). The basic idea is that the soil's reflectance spectrum holds information about its properties (like organic matter content or mineral composition). The relation between soil properties and the observable spectrum is usually not exactly know and is typically derived from statistical methods. Nowadays these methods are classified in the term machine learning, which comprises a vast pool of algorithms and methods for learning the relationship between pairs if input - output data (training data set). Within this pool of methods a Gaussian Process Regression (GPR) is newly emerging method (originating from Bayesian statistics) which is increasingly applied to applications in different fields. For example, it was successfully used to predict vegetation parameters from hyperspectral remote sensing data. In this study we apply GPR to predict soil organic carbon from soil spectroscopy data (400 - 2500 nm). We compare it to more traditional and widely used methods such as Partitial Least Squares Regression (PLSR), Random Forest (RF) and Gradient Boosted Regression Trees (GBRT). All these methods have the common ability to calculate a measure for the variable importance (wavelengths importance). The main advantage of GPR is its ability to also predict the variance of the target parameter. This makes it easy to see whether a prediction is reliable or not. The ability to choose from various covariance functions makes GPR a flexible method. This allows for including different assumptions or a priori knowledge about the data. For this study we use samples from three different locations to test the prediction accuracies. One

  14. Kinematic modelling of a 3-axis NC machine tool in linear and circular interpolation

    CERN Document Server

    Pessoles, Xavier; Rubio, Walter; 10.1007/s00170-009-2236-z

    2010-01-01

    Machining time is a major performance criterion when it comes to high-speed machining. CAM software can help in estimating that time for a given strategy. But in practice, CAM-programmed feed rates are rarely achieved, especially where complex surface finishing is concerned. This means that machining time forecasts are often more than one step removed from reality. The reason behind this is that CAM routines do not take either the dynamic performances of the machines or their specific machining tolerances into account. The present article seeks to improve simulation of high-speed NC machine dynamic behaviour and machining time prediction, offering two models. The first contributes through enhanced simulation of three-axis paths in linear and circular interpolation, taking high-speed machine accelerations and jerks into account. The second model allows transition passages between blocks to be integrated in the simulation by adding in a polynomial transition path that caters for the true machining environment t...

  15. Automatic feed system for ultrasonic machining

    Science.gov (United States)

    Calkins, Noel C.

    1994-01-01

    Method and apparatus for ultrasonic machining in which feeding of a tool assembly holding a machining tool toward a workpiece is accomplished automatically. In ultrasonic machining, a tool located just above a workpiece and vibrating in a vertical direction imparts vertical movement to particles of abrasive material which then remove material from the workpiece. The tool does not contact the workpiece. Apparatus for moving the tool assembly vertically is provided such that it operates with a relatively small amount of friction. Adjustable counterbalance means is provided which allows the tool to be immobilized in its vertical travel. A downward force, termed overbalance force, is applied to the tool assembly. The overbalance force causes the tool to move toward the workpiece as material is removed from the workpiece.

  16. Vibration attenuation of rotating machines by application of magnetorheological dampers to minimize energy losses in the rotor support

    Science.gov (United States)

    Zapoměl, J.; Ferfecki, P.

    2016-09-01

    A frequently used technological solution for minimization of undesirable effects caused by vibration of rotating machines consists in placing damping devices in the rotor supports. The application of magnetorheological squeeze film dampers enables their optimum performance to be achieved in a wide range of rotating speeds by adapting their damping effect to the current operating conditions. The damping force, which is produced by squeezing the layer of magnetorheological oil, can be controlled by changing magnetic flux passing through the lubricant. The force acting between the rotor and its frame is transmitted through the rolling element bearing, the lubricating layer and the squirrel spring. The loading of the bearing produces a time variable friction moment, energy losses, uneven rotor running, and has an influence on the rotor service life and the current fluctuation in electric circuits. The carried out research consisted in the development of a mathematical model of a magnetorheological squeeze film damper, its implementation into the computational models of rotor systems, and in performing the study on the dependence of the energy losses and variation of the friction moment on the damping force and its control. The new and computationally stable mathematical model of a magnetorheological squeeze film damper, its implementation in the computational models of rigid rotors and learning more on the energy losses generated in the rotor supports in dependence on the damping effect are the principal contributions of this paper. The results of the computational simulations prove that a suitable control of the damping force enables the energy losses to be reduced in a wide velocity range.

  17. Optimizing the way kinematical feed chains with great distance between slides are chosen for CNC machine tools

    Science.gov (United States)

    Lucian, P.; Gheorghe, S.

    2017-08-01

    This paper presents a new method, based on FRISCO formula, for optimizing the choice of the best control system for kinematical feed chains with great distance between slides used in computer numerical controlled machine tools. Such machines are usually, but not limited to, used for machining large and complex parts (mostly in the aviation industry) or complex casting molds. For such machine tools the kinematic feed chains are arranged in a dual-parallel drive structure that allows the mobile element to be moved by the two kinematical branches and their related control systems. Such an arrangement allows for high speed and high rigidity (a critical requirement for precision machining) during the machining process. A significant issue for such an arrangement it’s the ability of the two parallel control systems to follow the same trajectory accurately in order to address this issue it is necessary to achieve synchronous motion control for the two kinematical branches ensuring that the correct perpendicular position it’s kept by the mobile element during its motion on the two slides.

  18. New tools of relationship marketing for innovative projects of machine-building enterprises: crowdsourcing and crowdfunding

    Directory of Open Access Journals (Sweden)

    N.B. Kolotova

    2015-09-01

    Full Text Available The aim of the article. The aim of the article is justification of theoretical provisions for determining the nature and use of relationship marketing in innovative projects of machine-building enterprises. The results of the analysis. Today there are a lot of reasonable thoughts on the fundamental principles of relationship marketing concept origin. Generally, in our opinion, relationship marketing is a communication strategy intended to keep existing customers and to attract potential customers and key business partners. The peculiarity of the current development stage of information technologies is the widespread use of the following specific tools for development and commercialization of innovative projects: crowdsourcing and crowdfunding. These tools have already become a widely implemented in world practice and are vivid examples of a new interaction among subjects of innovation activity. Crowdsourcing and crowdfunding are relationship marketing tools by which a reduction of commercial risk innovative products is provided through attracting consumers in the processes of creating, testing, financing and promotion of new products, and so on. These tools use profound social nature of man, the desire to be «trailed» to something new (interesting, fashionable, promising, etc.. Marketing benefits of using crowdsourcing and crowdfunding for innovative projects are: - identifying of consumer preferences in the design stage of a new product; - the possibility to reduce the financial, intellectual and time spent on research, design, marketing research, etc.; - receiving of prior order and (or the advance payment for the projected product; - increasing customer loyalty, obtaining active «promoters», project’s «attorneys» as the clients; - the possibility of renewed interest in existing projects (food; - increasing interest in the innovative project on the part of other market entities (partners, investors, etc. on the basis of existing demand

  19. Effect of cutting parameters on sustainable machining performance of coated carbide tool in dry turning process of stainless steel 316

    Science.gov (United States)

    Bagaber, Salem A.; Yusoff, Ahmed Razlan

    2017-04-01

    The manufacturing industry aims to produce many products of high quality with relatively less cost and time. Different cutting parameters affect the machining performance of surface roughness, cutting force, and material removal rate. Nevertheless, a few studies reported on the effects of sustainable factors such as power consumed, cycle time during machining, and tool life on the dry turning of AISI 316. The present study aims to evaluate the machining performance of coated carbide in the machining of hard steel AISI 316 under the dry turning process. The influence of cutting parameters of cutting speed, feed rate, and depth of cut with their five (5) levels is established by a central composite design. Highly significant parameters were determined by analysis of variance (ANOVA), and the main effects of power consumed and time during machining, surface roughness, and tool wear were observed. Results showed that the cutting speed was proportional to power consumption and tool wear. Meanwhile, insignificant to surface roughness, feed rate most significantly affected surface roughness and power consumption followed by depth of cut.

  20. An attempt of CNC machining cycle’s application as a tool of the design feature library elaboration

    Directory of Open Access Journals (Sweden)

    Grabowik Cezary

    2017-01-01

    Full Text Available This paper presents a novel approach to a problem of the design feature library elaboration. As a tool of the design feature library development CNC machining cycles were proposed. Because of the great number of commercially available CNC machine controllers, with different CNC machining cycles definitions, it was necessary to make a decision about a research methodological framework, it is the selected CNC machine controller. Taking into account the criterion of popularity as the research framework the selected group of Sinumerik CNC machine controllers was chosen. Presented in the paper idea of the feature library development is based on an assumption saying that it is possible to find a relationship between a particular CNC machining cycle and the simple design feature or even compound design features. Identified, thanks to this assumption, set of the design features could be the base for elaboration of the design feature library. This solution, it is the feature library next gave opportunity for elaboration of the feature based design modelling module (FBDMM working in the SIEMENS NX system environment. Hence, the FBDMM module can support both a designer and CNC machine programmer which is possible due to received in the module modelling paradigm. In FBDMM module the removal feature based modelling technique is received.

  1. FPGA-based fused smart-sensor for tool-wear area quantitative estimation in CNC machine inserts.

    Science.gov (United States)

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used.

  2. FPGA-Based Fused Smart-Sensor for Tool-Wear Area Quantitative Estimation in CNC Machine Inserts

    Science.gov (United States)

    Trejo-Hernandez, Miguel; Osornio-Rios, Roque Alfredo; de Jesus Romero-Troncoso, Rene; Rodriguez-Donate, Carlos; Dominguez-Gonzalez, Aurelio; Herrera-Ruiz, Gilberto

    2010-01-01

    Manufacturing processes are of great relevance nowadays, when there is a constant claim for better productivity with high quality at low cost. The contribution of this work is the development of a fused smart-sensor, based on FPGA to improve the online quantitative estimation of flank-wear area in CNC machine inserts from the information provided by two primary sensors: the monitoring current output of a servoamplifier, and a 3-axis accelerometer. Results from experimentation show that the fusion of both parameters makes it possible to obtain three times better accuracy when compared with the accuracy obtained from current and vibration signals, individually used. PMID:22319304

  3. Machinability of Hastelloy C-276 Using Hot-pressed Sintered Ti(C7N3)-based Cermet Cutting Tools

    Institute of Scientific and Technical Information of China (English)

    XU Kaitao; ZOU Bin; HUANG Chuanzhen; YAO Yang; ZHOU Huijun; LIU Zhanqiang

    2015-01-01

    C-276 nickel-based alloy is a difficult-to-cut material. In high-speed machining of Hastelloy C-276, notching is a prominent fallure mode due to high mechanical properties of work piece, which results in the short tool life and low productivity. In this paper, a newly developed Ti(C7N3)-based cermet insert manufactured by a hot-pressing method is used to machine the C-276 nickel-based alloy, and its cutting performances are studied. Based on orthogonal experiment method, the influence of cutting parameters on tool life, material removal rates and surface roughness are investigated. Experimental research results indicate that the optimal cutting condition is a cutting speed of 50 m/min, depth of cut of 0.4 mm and feed rate of 0.15 mm/r if the tool life and material removal rates are considered comprehensively. In this case, the tool life is 32 min and material removal rates are 3000 mm3/min, which is appropriate to the rough machining. If the tool life and surface roughness are considered, the better cutting condition is a cutting speed of 75 m/min, depth of cut of 0.6 mm and feed rate of 0.1 mm/r. In this case, the surface roughness is 0.59mm. Notch wear, flank wear, chipping at the tool nose, built-up edge(BUE) and micro-cracks are found when Ti(C7N3)-based cermet insert turned Hastelloy C-276. Oxidation, adhesive, abrasive and diffusion are the wear mechanisms, which can be investigated by the observations of scanning electron microscope and energy-dispersive spectroscopy. This research will help to guide studies on the evaluation of machining parameters to further advance the productivity of nickel based alloy Hastelloy C-276 machining.

  4. A Web Tool for Generating High Quality Machine-readable Biological Pathways.

    Science.gov (United States)

    Ramirez-Gaona, Miguel; Marcu, Ana; Pon, Allison; Grant, Jason; Wu, Anthony; Wishart, David S

    2017-02-08

    PathWhiz is a web server built to facilitate the creation of colorful, interactive, visually pleasing pathway diagrams that are rich in biological information. The pathways generated by this online application are machine-readable and fully compatible with essentially all web-browsers and computer operating systems. It uses a specially developed, web-enabled pathway drawing interface that permits the selection and placement of different combinations of pre-drawn biological or biochemical entities to depict reactions, interactions, transport processes and binding events. This palette of entities consists of chemical compounds, proteins, nucleic acids, cellular membranes, subcellular structures, tissues, and organs. All of the visual elements in it can be interactively adjusted and customized. Furthermore, because this tool is a web server, all pathways and pathway elements are publicly accessible. This kind of pathway "crowd sourcing" means that PathWhiz already contains a large and rapidly growing collection of previously drawn pathways and pathway elements. Here we describe a protocol for the quick and easy creation of new pathways and the alteration of existing pathways. To further facilitate pathway editing and creation, the tool contains replication and propagation functions. The replication function allows existing pathways to be used as templates to create or edit new pathways. The propagation function allows one to take an existing pathway and automatically propagate it across different species. Pathways created with this tool can be "re-styled" into different formats (KEGG-like or text-book like), colored with different backgrounds, exported to BioPAX, SBGN-ML, SBML, or PWML data exchange formats, and downloaded as PNG or SVG images. The pathways can easily be incorporated into online databases, integrated into presentations, posters or publications, or used exclusively for online visualization and exploration. This protocol has been successfully applied to

  5. Study on Surface Integrity of AISI 1045 Carbon Steel when machined by Carbide Cutting Tool under wet conditions

    Directory of Open Access Journals (Sweden)

    Tamin N. Fauzi

    2017-01-01

    Full Text Available This paper presents the evaluation of surface roughness and roughness profiles when machining carbon steel under wet conditions with low and high cutting speeds. The workpiece materials and cutting tools selected in this research were AISI 1045 carbon steel and canela carbide inserts graded PM25, respectively. The cutting tools undergo machining tests by CNC turning operations and their performances were evaluated by their surface roughness value and observation of the surface roughness profile. The machining tests were held at varied cutting speeds of 35 to 53 m/min, feed rate of 0.15 to 0.50 mm/rev and a constant depth of cut of 1 mm. From the analysis, it was found that surface roughness increased as the feed rate increased. Varian of surface roughness was suspected due to interaction between cutting speeds and feed rates as well as nose radius conditions; whether from tool wear or the formation of a built-up edge. This study helps us understand the effect of cutting speed and feed rate on surface integrity, when machining AISI 1045 carbon steel using carbide cutting tools, under wet cutting conditions.

  6. The Application of the GM (1,1) Metabolism Model to Error Data Processing of NC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    LIAO De-gang; XIONG Xiao-hong

    2003-01-01

    This paper applied the gray system theory to error data processing of NC machine tools ac cording to the characteristic. It presented the gray metabolism model of error data processing. The test method for the model needs less capacity. Practice proved that the method is simple, calculation is easy, and results are exact.

  7. 对刀仪在数控机床上的应用%Self-made tool auto-checking instrument used in CNC machine tool

    Institute of Scientific and Technical Information of China (English)

    宋长双; 薛平萍; 李多祥

    2011-01-01

    为了提高数控机床加工的效率和精度,在数控系统软件支持下,增设一个相对独立的自动对刀程序模块来实现简易的自动对刀控制.%In order to improve the efficiency of CNC machine tool, the addition of a relatively independent of the automatic tool program modules achieve easy control of automatic tool on the support of CNC system software.

  8. The influence of vibrations on surface roughness formed during precision boring

    Science.gov (United States)

    Korzeniewski, Dariusz; Znojkiewicz, Natalia

    2017-01-01

    In this paper, the analysis of vibrations on surface roughness generated during boring with the application of the conventional boring tool and one with the damper is presented. The experiments included the measurement of vibration accelerations carried out with the piezoelectric sensor, as well as the evaluation of surface roughness parameters after each machining pass. The obtained results reveal that in the investigated range, no stability loss was found. Furthermore, the growth of the rotational speed induces the increase of vibration level, as well as the growth of the differences between the vibration values generated during boring with the conventional tool and one equipped with damper. Vibrations have also the direct influence on the machined surface roughness. In case of the tool equipped with the damper, the tool's overhang L had more intense influence than rotational speed n. However, for the conventional boring tool this dependency was unequivocal.

  9. A Tentative Study on Dynamics of a New Parallel NC Machine Tool with Long Travel, Large Rotating Angle and High Moving Speed

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    In view of the structure of traditional five-coord in ate machine tool, the work-piece and machine tool often move along their respec tive guides simultaneously on the whole. In this kind of machine structure, the total mass of moving parts including work-pieces, fixtures, rotating table, wor king table and so on is often very large. Besides, the elastic reform of transmi ssion and the viscous friction force of the guide can not be ignored. As a resul t, the machine tool can not move with high velocity and...

  10. Thermo-energetic design of machine tools a systemic approach to solve the conflict between power efficiency, accuracy and productivity demonstrated at the example of machining production

    CERN Document Server

    2015-01-01

    The approach to the solution within the CRC/TR 96 financed by the German Research Foundation DFG aims at measures that will allow manufacturing accuracy to be maintained under thermally unstable conditions with increased productivity, without an additional demand for energy for tempering. The challenge of research in the CRC/TR 96 derives from the attempt to satisfy the conflicting goals of reducing energy consumption and increasing accuracy and productivity in machining. In the current research performed in 19 subprojects within the scope of the CRC/TR 96, correction and compensation solutions that influence the thermo-elastic machine tool behaviour efficiently and are oriented along the thermo-elastic functional chain are explored and implemented. As part of this general objective, the following issues must be researched and engineered in an interdisciplinary setting and brought together into useful overall solutions:   1.  Providing the modelling fundamentals to calculate the heat fluxes and the resulti...

  11. Comparative investigation of vibration and current monitoring for prediction of mechanical and electrical faults in induction motor based on multiclass-support vector machine algorithms

    Science.gov (United States)

    Gangsar, Purushottam; Tiwari, Rajiv

    2017-09-01

    This paper presents an investigation of vibration and current monitoring for effective fault prediction in induction motor (IM) by using multiclass support vector machine (MSVM) algorithms. Failures of IM may occur due to propagation of a mechanical or electrical fault. Hence, for timely detection of these faults, the vibration as well as current signals was acquired after multiple experiments of varying speeds and external torques from an experimental test rig. Here, total ten different fault conditions that frequently encountered in IM (four mechanical fault, five electrical fault conditions and one no defect condition) have been considered. In the case of stator winding fault, and phase unbalance and single phasing fault, different level of severity were also considered for the prediction. In this study, the identification has been performed of the mechanical and electrical faults, individually and collectively. Fault predictions have been performed using vibration signal alone, current signal alone and vibration-current signal concurrently. The one-versus-one MSVM has been trained at various operating conditions of IM using the radial basis function (RBF) kernel and tested for same conditions, which gives the result in the form of percentage fault prediction. The prediction performance is investigated for the wide range of RBF kernel parameter, i.e. gamma, and selected the best result for one optimal value of gamma for each case. Fault predictions has been performed and investigated for the wide range of operational speeds of the IM as well as external torques on the IM.

  12. Diagnostics of a crack in a load coupling of a gas turbine using the machine model and the analysis of the shaft vibrations

    Science.gov (United States)

    Pennacchi, Paolo; Vania, Andrea

    2008-07-01

    The diagnostics of malfunctions that can cause catastrophic failures has to be made in early stage in the industrial environment. Often flexible couplings are employed in industrial rotating machines when gearboxes and heavy thermal gradients are present. The hot and cold alignment of these couplings can be very different. Severe misalignments can generate cracks in the stub shafts, which can propagate in operating condition. Owing to the flexural flexibility of the load coupling, the shaft vibrations may be not noticeably affected by some typical symptoms that usually point out the presence of a crack, like twice per revolution harmonics in the vibration spectrum. Anyhow, suitable diagnostic strategies can detect clear fault symptoms, while model-based methods can confirm the occurrence of the shaft bow induced by the progressive yielding of a load coupling due to a crack. This paper shows as a model-based diagnostic methodology would have allowed a crack in a load coupling of a gas turbine to be identified before a serious failure happened by means of the shaft vibration analysis under operating conditions and rated speed. Finally, the vibrations caused by the shaft bow due to the propagation of a crack in the stub shaft of the coupling have been simulated using suitable equivalent excitations, the magnitude and phase of which have been estimated by means of a model-based identification method.

  13. 49 CFR 1242.28 - Roadway machines, small tools and supplies, and snow removal (accounts XX-19-36 to XX-19-38...

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 9 2010-10-01 2010-10-01 false Roadway machines, small tools and supplies, and... PASSENGER SERVICE FOR RAILROADS 1 Operating Expenses-Way and Structures § 1242.28 Roadway machines, small tools and supplies, and snow removal (accounts XX-19-36 to XX-19-38, inclusive). Separate...

  14. Researches Concerning to Minimize Vibrations when Processing Normal Lathe

    Directory of Open Access Journals (Sweden)

    Lenuța Cîndea

    2015-09-01

    Full Text Available In the cutting process, vibration is inevitable appearance, and in situations where the amplitude exceeds the limits of precision dimensional and shape of the surfaces generated vibrator phenomenon is detrimental.Field vibration is an issue of increasingly developed, so the futures will a better understanding of them and their use even in other sectors.The paper developed experimental measurement of vibrations at the lathe machining normal. The scheme described kinematical machine tool, cutting tool, cutting conditions, presenting experimental facility for measuring vibration occurring at turning. Experimental results have followed measurement of amplitude, which occurs during interior turning the knife without silencer incorporated. The tests were performed continuously for different speed, feed and depth of cut.

  15. An autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools

    Science.gov (United States)

    Liu, Samuel M. Y.; Cheung, Benny C. F.; Whitehouse, David; Cheng, Ching-Hsiang

    2016-11-01

    An in situ measurement is of prime importance when trying to maintain the position of the workpiece for further compensation processes in order to improve the accuracy and efficiency of the precision machining of three dimensional (3D) surfaces. However, the coordinates of most of the machine tools with closed machine interfaces and control system are not accessible for users, which make it difficult to use the motion axes of the machine tool for in situ measurements. This paper presents an autonomous multisensor in situ metrology system for enabling high dynamic range measurement of 3D surfaces on precision machine tools. It makes use of a designed tool path and an additional motion sensor to assist the registration of time-space data for the position estimation of a 2D laser scanner which measures the surface with a high lateral resolution and large area without the need to interface with the machine tool system. A prototype system was built and integrated into an ultra-precision polishing machine. Experimental results show that it measures the 3D surfaces with high resolution, high repeatability, and large measurement range. The system not only improves the efficiency and accuracy of the precision machining process but also extends the capability of machine tools.

  16. Inventory management performance in machine tool SMEs: What factors do influence them?

    Directory of Open Access Journals (Sweden)

    Rajeev Narayana Pillai

    2010-12-01

    Full Text Available Small and Medium Enterprises (SMEs are one of the principal driving forces in the development of an economy because of its significant contribution in terms of number of enterprises, employment, output and exports in most developing as well as developed countries. But SMEs, particularly in developing countries like India, face constraints in key areas such as technology, finance, marketing and human resources. Moreover these SMEs have been exposed to intense competition since early 1990s because of globalization. However, globalization, the process of continuing integration of the countries in the world has opened up new opportunities for SMEs of developing countries to cater to wider international market which brings out the need for these SMEs to develop competitiveness for their survival as well as growth. It is observed from literature that pursuing appropriate IM practice is one of the ways of acquiring competitiveness among others, by effectively managing and minimizing inventory investment. Inventory management can therefore be one of the crucial determinants of competitiveness as well as operational performance of SMEs in inventory intensive manufacturing industries. The key issue is whether Indian SMEs pursue better IM practices with an intension to reduce their inventory cost and enhance their competitiveness. If so, what are the IM practices pursued by these enterprises? What are the factors which influence the inventory cost and IM performance of enterprises? These questions have been addressed in this study with reference to machine tool SMEs located in the city of Bangalore, India.

  17. Bayesian zero-failure reliability modeling and assessment method for multiple numerical control (NC) machine tools

    Institute of Scientific and Technical Information of China (English)

    阚英男; 杨兆军; 李国发; 何佳龙; 王彦鹍; 李洪洲

    2016-01-01

    A new problem that classical statistical methods are incapable of solving is reliability modeling and assessment when multiple numerical control machine tools (NCMTs) reveal zero failures after a reliability test. Thus, the zero-failure data form and corresponding Bayesian model are developed to solve the zero-failure problem of NCMTs, for which no previous suitable statistical model has been developed. An expert−judgment process that incorporates prior information is presented to solve the difficulty in obtaining reliable prior distributions of Weibull parameters. The equations for the posterior distribution of the parameter vector and the Markov chain Monte Carlo (MCMC) algorithm are derived to solve the difficulty of calculating high-dimensional integration and to obtain parameter estimators. The proposed method is applied to a real case; a corresponding programming code and trick are developed to implement an MCMC simulation in WinBUGS, and a mean time between failures (MTBF) of 1057.9 h is obtained. Given its ability to combine expert judgment, prior information, and data, the proposed reliability modeling and assessment method under the zero failure of NCMTs is validated.

  18. SAMSVM: A tool for misalignment filtration of SAM-format sequences with support vector machine.

    Science.gov (United States)

    Yang, Jianfeng; Ding, Xiaofan; Sun, Xing; Tsang, Shui-Ying; Xue, Hong

    2015-12-01

    Sequence alignment/map (SAM) formatted sequences [Li H, Handsaker B, Wysoker A et al., Bioinformatics 25(16):2078-2079, 2009.] have taken on a main role in bioinformatics since the development of massive parallel sequencing. However, because misalignment of sequences poses a significant problem in analysis of sequencing data that could lead to false positives in variant calling, the exclusion of misaligned reads is a necessity in analysis. In this regard, the multiple features of SAM-formatted sequences can be treated as vectors in a multi-dimension space to allow the application of a support vector machine (SVM). Applying the LIBSVM tools developed by Chang and Lin [Chang C-C, Lin C-J, ACM Trans Intell Syst Technol 2:1-27, 2011.] as a simple interface for support vector classification, the SAMSVM package has been developed in this study to enable misalignment filtration of SAM-formatted sequences. Cross-validation between two simulated datasets processed with SAMSVM yielded accuracies that ranged from 0.89 to 0.97 with F-scores ranging from 0.77 to 0.94 in 14 groups characterized by different mutation rates from 0.001 to 0.1, indicating that the model built using SAMSVM was accurate in misalignment detection. Application of SAMSVM to actual sequencing data resulted in filtration of misaligned reads and correction of variant calling.

  19. Using machine learning tools to model complex toxic interactions with limited sampling regimes.

    Science.gov (United States)

    Bertin, Matthew J; Moeller, Peter; Guillette, Louis J; Chapman, Robert W

    2013-03-19

    A major impediment to understanding the impact of environmental stress, including toxins and other pollutants, on organisms, is that organisms are rarely challenged by one or a few stressors in natural systems. Thus, linking laboratory experiments that are limited by practical considerations to a few stressors and a few levels of these stressors to real world conditions is constrained. In addition, while the existence of complex interactions among stressors can be identified by current statistical methods, these methods do not provide a means to construct mathematical models of these interactions. In this paper, we offer a two-step process by which complex interactions of stressors on biological systems can be modeled in an experimental design that is within the limits of practicality. We begin with the notion that environment conditions circumscribe an n-dimensional hyperspace within which biological processes or end points are embedded. We then randomly sample this hyperspace to establish experimental conditions that span the range of the relevant parameters and conduct the experiment(s) based upon these selected conditions. Models of the complex interactions of the parameters are then extracted using machine learning tools, specifically artificial neural networks. This approach can rapidly generate highly accurate models of biological responses to complex interactions among environmentally relevant toxins, identify critical subspaces where nonlinear responses exist, and provide an expedient means of designing traditional experiments to test the impact of complex mixtures on biological responses. Further, this can be accomplished with an astonishingly small sample size.

  20. A study on fluid flow simulation in the cooling systems of machine tools

    Science.gov (United States)

    Olaru, I.

    2016-08-01

    This paper aims analysing the type of coolants and the correct choice of that as well as the dispensation in the processing area to control the temperature resulted from the cutting operation and the choose of the cutting operating modes. A high temperature in the working area over a certain amount can be harmful in terms of the quality of resulting surface and that could have some influences on the life of the cutting tool. The coolant chosen can be a combination of different cooling fluids in order to achieve a better cooling of the cutting area at the same time for carrying out the proper lubrication of that area. The fluid flow parameters of coolant can be influenced by the nature of the fluid or fluids used, the geometry of the nozzle used which generally has a convergent-divergent geometry in order to achieve a better dispersion of the coolant / lubricant on the area to be processed. A smaller amount of fluid is important in terms of the economy lubricant, because they are quite expensive. A minimal amount of lubricant may have a better impact on the environment and the health of the operator because the coolants in contact with overheated machined surface may develop a substantial amount of these gases that are not always beneficial to health.

  1. Applying CBR to machine tool product configuration design oriented to customer requirements

    Science.gov (United States)

    Wang, Pengjia; Gong, Yadong; Xie, Hualong; Liu, Yongxian; Nee, Andrew Yehching

    2017-01-01

    Product customization is a trend in the current market-oriented manufacturing environment. However, deduction from customer requirements to design results and evaluation of design alternatives are still heavily reliant on the designer's experience and knowledge. To solve the problem of fuzziness and uncertainty of customer requirements in product configuration, an analysis method based on the grey rough model is presented. The customer requirements can be converted into technical characteristics effectively. In addition, an optimization decision model for product planning is established to help the enterprises select the key technical characteristics under the constraints of cost and time to serve the customer to maximal satisfaction. A new case retrieval approach that combines the self-organizing map and fuzzy similarity priority ratio method is proposed in case-based design. The self-organizing map can reduce the retrieval range and increase the retrieval efficiency, and the fuzzy similarity priority ratio method can evaluate the similarity of cases comprehensively. To ensure that the final case has the best overall performance, an evaluation method of similar cases based on grey correlation analysis is proposed to evaluate similar cases to select the most suitable case. Furthermore, a computer-aided system is developed using MATLAB GUI to assist the product configuration design. The actual example and result on an ETC series machine tool product show that the proposed method is effective, rapid and accurate in the process of product configuration. The proposed methodology provides a detailed instruction for the product configuration design oriented to customer requirements.

  2. SKYNET: an efficient and robust neural network training tool for machine learning in astronomy

    Science.gov (United States)

    Graff, Philip; Feroz, Farhan; Hobson, Michael P.; Lasenby, Anthony

    2014-06-01

    We present the first public release of our generic neural network training algorithm, called SKYNET. This efficient and robust machine learning tool is able to train large and deep feed-forward neural networks, including autoencoders, for use in a wide range of supervised and unsupervised learning applications, such as regression, classification, density estimation, clustering and dimensionality reduction. SKYNET uses a `pre-training' method to obtain a set of network parameters that has empirically been shown to be close to a good solution, followed by further optimization using a regularized variant of Newton's method, where the level of regularization is determined and adjusted automatically; the latter uses second-order derivative information to improve convergence, but without the need to evaluate or store the full Hessian matrix, by using a fast approximate method to calculate Hessian-vector products. This combination of methods allows for the training of complicated networks that are difficult to optimize using standard backpropagation techniques. SKYNET employs convergence criteria that naturally prevent overfitting, and also includes a fast algorithm for estimating the accuracy of network outputs. The utility and flexibility of SKYNET are demonstrated by application to a number of toy problems, and to astronomical problems focusing on the recovery of structure from blurred and noisy images, the identification of gamma-ray bursters, and the compression and denoising of galaxy images. The SKYNET software, which is implemented in standard ANSI C and fully parallelized using MPI, is available at http://www.mrao.cam.ac.uk/software/skynet/.

  3. Applying CBR to machine tool product configuration design oriented to customer requirements

    Science.gov (United States)

    Wang, Pengjia; Gong, Yadong; Xie, Hualong; Liu, Yongxian; Nee, Andrew Yehching

    2016-03-01

    Product customization is a trend in the current market-oriented manufacturing environment. However, deduction from customer requirements to design results and evaluation of design alternatives are still heavily reliant on the designer's experience and knowledge. To solve the problem of fuzziness and uncertainty of customer requirements in product configuration, an analysis method based on the grey rough model is presented. The customer requirements can be converted into technical characteristics effectively. In addition, an optimization decision model for product planning is established to help the enterprises select the key technical characteristics under the constraints of cost and time to serve the customer to maximal satisfaction. A new case retrieval approach that combines the self-organizing map and fuzzy similarity priority ratio method is proposed in case-based design. The self-organizing map can reduce the retrieval range and increase the retrieval efficiency, and the fuzzy similarity priority ratio method can evaluate the similarity of cases comprehensively. To ensure that the final case has the best overall performance, an evaluation method of similar cases based on grey correlation analysis is proposed to evaluate similar cases to select the most suitable case. Furthermore, a computer-aided system is developed using MATLAB GUI to assist the product configuration design. The actual example and result on an ETC series machine tool product show that the proposed method is effective, rapid and accurate in the process of product configuration. The proposed methodology provides a detailed instruction for the product configuration design oriented to customer requirements.

  4. Parametric Optimization of Wire Electrical Discharge Machining of Powder Metallurgical Cold Worked Tool Steel using Taguchi Method

    Science.gov (United States)

    Sudhakara, Dara; Prasanthi, Guvvala

    2016-08-01

    Wire Cut EDM is an unconventional machining process used to build components of complex shape. The current work mainly deals with optimization of surface roughness while machining P/M CW TOOL STEEL by Wire cut EDM using Taguchi method. The process parameters of the Wire Cut EDM is ON, OFF, IP, SV, WT, and WP. L27 OA is used for to design of the experiments for conducting experimentation. In order to find out the effecting parameters on the surface roughness, ANOVA analysis is engaged. The optimum levels for getting minimum surface roughness is ON = 108 µs, OFF = 63 µs, IP = 11 A, SV = 68 V and WT = 8 g.

  5. Effect of Micro Electrical Discharge Machining Process Conditions on Tool Wear Characteristics: Results of an Analytic Study

    DEFF Research Database (Denmark)

    Puthumana, Govindan; P., Rajeev

    2016-01-01

    Micro electrical discharge machining is one of the established techniques to manufacture high aspect ratio features on electrically conductive materials. This paper presents the results and inferences of an analytical study for estimating theeffect of process conditions on tool electrode wear...... characteristicsin micro-EDM process. A new approach with two novel factors anticipated to directly control the material removal mechanism from the tool electrode are proposed; using discharge energyfactor (DEf) and dielectric flushing factor (DFf). The results showed that the correlation between the tool wear rate...

  6. An Experiment to Explain Depth of Cut Notch Wear of Ceramic Tools in Ni- based Super-alloy Machining

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    Inconel 718, a high temperature alloy, is extensive ly used in aircraft, gas engines and nuclear-power plants. It is generally known that the life of ceramic cutting tools in machining Inconel 718 is often restric ted by depth-of-cut (DOC) notch wear. In view of the number of various factors involved and the variety of tool materi als and cutting conditions available, the analysis of the DOC notch wear is very difficult. According to previous work concerning the DOC notch wear of ceramics tools, some A...

  7. 数控机床典型电气故障诊断与维修%Diagnosis and Maintenance of Electrical Breakdown of CNC Machine Tools

    Institute of Scientific and Technical Information of China (English)

    张晶辉

    2016-01-01

    With the development of numerical control technology ,the maintenance of CNC machine tools has become increasingly important .A CNC machine tool is mainly composed of electrical ,mechanical and hydraulic components .This paper discussed the diagnosis and maintenance of electrical breakdown of CNC machine tools .Through the understanding of the electrical principle of machine tools ,we can improve the efficience of repair and maintenance of the electrical system of machine tools .%随着数控技术的发展,数控机床的维修已越来越重要。主要对数控机床电气部分的故障诊断与维修进行了介绍。基于对机床电气原理的认识,可以更好地对机床电气系统进行维修与维护。

  8. The Spindle Unit of Machine Tool(Ⅱ)%机床的主轴单元(下)

    Institute of Scientific and Technical Information of China (English)

    张曙; 张柄生; 卫汉华

    2016-01-01

    通过回顾机床主轴发展历程,指出电主轴在高端数控机床的应用日益广泛。继而详尽地阐述了机床主轴单元的设计要点,包括轴承、润滑和冷却以及刀具接口等。接着对主轴的静动态和热性能分析以及建模仿真进行了全面介绍。最后指出主轴的工况监控、智能化和自适应控制是新一代电主轴的重要特征和未来发展趋势。%Reviewing the development of machine tool spindle, it points out that the application of motorized spindle in high-end CNC machine tools is becoming more and more widely. It shows the detail about the design key points of machine tool spindle unit such as bearing, lubrication, cooling and cutting tool interface. It illus-trates the static and dynamic and thermal performance analysis and modeling simulation for spindle unit, pre-sents the important characteristics and the future development trend in condition monitoring, intelligent and adaptive control ect.

  9. Real Aperture Radar interferometry as a tool for buildings vibration monitoring: Limits and potentials from an experimental study

    Science.gov (United States)

    Luzi, Guido; Monserrat, Oriol; Crosetto, Michele

    2012-06-01

    In the last decade several researchers have dealt with the potential of radar interferometry as a remote sensing tool able to provide measurements of vibrations of large structures. More recently the technique has been consolidated thanks to the recent introduction on the market of specifically devoted radar instruments. Exploiting the interferometric capability of coherent radar, successful monitoring of bridges, towers and wind turbine powers has been achieved. This technique allowed looking at the frequency behaviour of civil structures and estimating their amplitude of displacement in the order of fraction of millimetres. The activity here described reports the results of an experimental investigation aimed at evaluating the effectiveness of a coherent Real-Aperture-Radar sensor to estimate the vibration of buildings in an urban environment, through an ambient vibration testing, where the expected amplitude vibration spans within a few to some tens of microns. Critical aspects affecting the retrieval of this information are here discussed, on the basis of some experimental data collected in the last year with a microwave interferometer working at Ku band and available on the market. Preliminary results are shown and suggestions related to the measurement procedures are discussed.

  10. Structural bionic design for high——speed machine tool working table based on distribution rules of leaf veins

    Institute of Scientific and Technical Information of China (English)

    XING DengHai; CHEN WuYi; ZHAO Ling; MA JianFeng

    2012-01-01

    High-speed machine tool working table restrains the machining accuracy and machining efficiency,so lightweight design of the table is an important issue.In nature,leaf has developed a plate structure that maximizes the surface-to-volume ratio.It can be seen as a plate structure stiffened by veins.Compared with a high-speed machine tool working table,leaf veins play a role of supporting part which is similar to that of stiffening ribs,and they can provide some new design ideas for lightweight design of the table.In this paper,distribution rules of leaf veins were investigated,and a structural bionic design for the table was achieved based on regulation of leaf veins.First,statistical analysis on geometric structure of leaf veins was carried out,and four distribution rules were obtained.Then,relevant mechanical models were developed and analyzed in finite element soft-ware.Based on the results from mechanical analysis on those relevant models,the four distribution rules were translated into the design rules and a structural bionic design for the working table was achieved.Both simulation and experimental verifications were carried out,and results showed that the average displacement of the working table was reduced by about 33.9%.

  11. Thermal Error Modeling Method with the Jamming of Temperature-Sensitive Points' Volatility on CNC Machine Tools

    Science.gov (United States)

    MIAO, Enming; LIU, Yi; XU, Jianguo; LIU, Hui

    2017-03-01

    Aiming at the deficiency of the robustness of thermal error compensation models of CNC machine tools, the mechanism of improving the models' robustness is studied by regarding the Leaderway-V450 machining center as the object. Through the analysis of actual spindle air cutting experimental data on Leaderway-V450 machine, it is found that the temperature-sensitive points used for modeling is volatility, and this volatility directly leads to large changes on the collinear degree among modeling independent variables. Thus, the forecasting accuracy of multivariate regression model is severely affected, and the forecasting robustness becomes poor too. To overcome this effect, a modeling method of establishing thermal error models by using single temperature variable under the jamming of temperature-sensitive points' volatility is put forward. According to the actual data of thermal error measured in different seasons, it is proved that the single temperature variable model can reduce the loss of forecasting accuracy resulted from the volatility of temperature-sensitive points, especially for the prediction of cross quarter data, the improvement of forecasting accuracy is about 5 μm or more. The purpose that improving the robustness of the thermal error models is realized, which can provide a reference for selecting the modeling independent variable in the application of thermal error compensation of CNC machine tools.

  12. Process Design of Shaft Machining with General Machine Tool%普通机床加工轴的工艺设计

    Institute of Scientific and Technical Information of China (English)

    王德鹏

    2015-01-01

    通常用轴传递动力和扭矩或者支撑位于轴上的传动零部件,并使之保持相对位置。根据轴的受力特点不同,一般采用阶梯轴结构,才能满足要求。在普通机床轴的加工,效率较低,精度不容易达到要求。本文通过某阶梯轴的零件分析及工艺分析,设计出了较合理的机械加工工艺,在保证加工质量的前提上,对提高生产效率,合理使用机床等进行了有益探讨。%Usually the shaft is used to transmit power and torque or support the transmission parts on the shaft and keep their position. According to the different loading features of the shaft, usually stepped shaft is adopted to meet the requirements. The processing of shaft with general machine tool is low in efficiency and can't meet the desired accuracy. Through part analysis and process analysis of a kind of stepped shaft, a reasonable machining process technology is designed, which is beneficial for improving production efficiency and reasonable use of the machine tool o the basis of ensuring the processing quality.

  13. FCC Machine Vibration for Analysis and Countermeasures%催化裂化烟机振动原因分析及对策

    Institute of Scientific and Technical Information of China (English)

    艾克利; 艾小兵; 李宏; 任谏峰; 郭保宏; 杨东元

    2011-01-01

    烟气轮机是原料油催化裂化过程中重要的能量回收装置,其运行状况不仅关系到装置整体能耗水平、而且还对整套机组的安全运行有着重要的影响。文章介绍了烟机的原理和功能,并对催化裂化装置运行中引起烟机振动常见原因进行分析。通过控制工艺参数等措施,使榆炼催化裂化装置配套烟机启动初始振动值控制在3μm。%Smoke turbo-generator is raw material oil FCC process important energy recovery equipment,smoke turbo-generator operation condition quality,relates to energy level,but also related to set of unit operation,catalytic cracking unit set,is the important guarantee of the stable production.The paper simply introduced the principle and function of machine of cigarette machine,and the simple common reasons vibration analysis and countermeasures were introduced.The vibration of smoke turbo-generator was 3 ?m.

  14. 汽车铸造及装配作业场所振动工具手传振动测量和分析%Measurement and analysis of hand-transmitted vibration of vibration tools in workplace for automobile casting and assembly

    Institute of Scientific and Technical Information of China (English)

    谢晓霜; 祁成; 杜燮祎; 史伟伟; 张敏

    2016-01-01

    Objective To investigate the features of hand-transmitted vibration of common vibration tools in the workplace for automobile casting and assembly.Methods From September to October,2014,measurement and spectral analysis were performed for 16 typical hand tools (including percussion drill,pneumatic wrench,grinding machine,internal grinder,and arc welding machine) in 6 workplaces for automobile casting and assembly according to ISO 5349-1-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-part 1:General requirements and ISO 5349-2-2001 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2:Practical guidance for measurement in the workplace.Results The vibration acceleration waveforms of shearing machine,arc welding machine,and pneumatic wrench were mainly impact wave and random wave,while those of internal grinder,angle grinder,percussion drill,and grinding machine were mainly long-and short-period waves.The daily exposure duration to vibration of electric wrench,pneumatic wrench,shearing machine,percussion drill,and internal grinder was about 150 minutes,while that of plasma cutting machine,angle grinder,grinding machine,bench grinder,and arc welding machine was about 400 minutes.The range of vibration total value (ahw) was as follows:pneumatic wrench 0.30~11.04 m/s2,grinding wheel 1.61 ~8.97 m/s2,internal grinder 1.46~8.70 m/s2,percussion drill 11.10~14.50 m/s2,and arc welding machine 0.21~2.18 m/s2.The workers engaged in cleaning had the longest daily exposure duration to vibration,and the effective value of 8-hour energy-equivalent frequency-weighted acceleration for them[A (8)] was 8.03 m/s2,while this value for workers engaged in assembly was 4.78 m/s2.The frequency spectrogram with an 1/3-time frequency interval showed that grinding machine,angle grinder,and percussion drill had a high vibration acceleration,and the vibration limit curve was recommended

  15. Experimental Investigation of Machining Parameters in Drilling Operation Using Conventional and CNC Machines on Titanium Alloy

    Directory of Open Access Journals (Sweden)

    B.Suresh kumar

    2014-05-01

    Full Text Available Titanium alloy is one of the newer materials in manufacturing industries due to its high strength to weight ratio and corrosion resistance properties. Making a hole on this component is very difficult task due to its poor machinability. Hence, the machining parameter investigation on titanium alloy material is very important for predicting the drilling performance characteristics. In addition, the modern manufacturing industries are used the conventional drilling machine and CNC drilling machines for making a hole. In the sense, the main aim of this work is to investigate the machining parameters on vibration, thrust force, torque, machining time, burr dimension, tool wear and surface roughness occurrences when drilling titanium alloy with conventional and CNC machines. The effects of spindle speed and feed rate on these responses were reported.

  16. Machine Assistance in Collection Building: New Tools, Research, Issues, and Reflections

    Directory of Open Access Journals (Sweden)

    Steve Mitchell

    2006-12-01

    Full Text Available Digital tool making offers many challenges, involving much trial and error. Developing machine learning and assistance in automated and semi-automated Internet resource discovery, metadata generation, and rich-text identification provides opportunities for great discovery, innovation, and the potential for transformation of the library community. The areas of computer science involved, as applied to the library applications addressed, are among that discipline’s leading edges. Making applied research practical and applicable, through placement within library/collection-management systems and services, involves equal parts computer scientist, research librarian, and legacy-systems archaeologist. Still, the early harvest is there for us now, with a large harvest pending. Data Fountains and iVia, the projects discussed, demonstrate this. Clearly, then, the present would be a good time for the library community to more proactively and significantly engage with this technology and research, to better plan for its impacts, to more proactively take up the challenges involved in its exploration, and to better and more comprehensively guide effort in this new territory. The alternative to doing this is that others will develop this territory for us, do it not as well, and sell it back to us at a premium. Awareness of this technology and its current capabilities, promises, limitations, and probable major impacts needs to be generalized throughout the library management, metadata, and systems communities. This article charts recent work, promising avenues for new research and development, and issues the library community needs to understand.

  17. Axiomatic Design and Fabrication of Composite Structures - Applications in Robots, Machine Tools, and Automobiles

    Science.gov (United States)

    Lee, Dai Gil; Suh, Nam Pyo

    2005-11-01

    The idea that materials can be designed to satisfy specific performance requirements is relatively new. With high-performance composites, however, the entire process of designing and fabricating a part can be worked out before manufacturing. The purpose of this book is to present an integrated approach to the design and manufacturing of products from advanced composites. It shows how the basic behavior of composites and their constitutive relationships can be used during the design stage, which minimizes the complexity of manufacturing composite parts and reduces the repetitive "design-build-test" cycle. Designing it right the first time is going to determine the competitiveness of a company, the reliability of the part, the robustness of fabrication processes, and ultimately, the cost and development time of composite parts. Most of all, it should expand the use of advanced composite parts in fields that use composites only to a limited extent at this time. To achieve these goals, this book presents the design and fabrication of novel composite parts made for machine tools and other applications like robots and automobiles. This book is suitable as a textbook for graduate courses in the design and fabrication of composites. It will also be of interest to practicing engineers learning about composites and axiomatic design. A CD-ROM is included in every copy of the book, containing Axiomatic CLPT software. This program, developed by the authors, will assist readers in calculating material properties from the microstructure of the composite. This book is part of the Oxford Series on Advanced Manufacturing.

  18. Developing Prognosis Tools to Identify Learning Difficulties in Children Using Machine Learning Technologies.

    Science.gov (United States)

    Loizou, Antonis; Laouris, Yiannis

    2011-09-01

    The Mental Attributes Profiling System was developed in 2002 (Laouris and Makris, Proceedings of multilingual & cross-cultural perspectives on Dyslexia, Omni Shoreham Hotel, Washington, D.C, 2002), to provide a multimodal evaluation of the learning potential and abilities of young children's brains. The method is based on the assessment of non-verbal abilities using video-like interfaces and was compared to more established methodologies in (Papadopoulos, Laouris, Makris, Proceedings of IDA 54th annual conference, San Diego, 2003), such as the Wechsler Intelligence Scale for Children (Watkins et al., Psychol Sch 34(4):309-319, 1997). To do so, various tests have been applied to a population of 134 children aged 7-12 years old. This paper addresses the issue of identifying a minimal set of variables that are able to accurately predict the learning abilities of a given child. The use of Machine Learning technologies to do this provides the advantage of making no prior assumptions about the nature of the data and eliminating natural bias associated with data processing carried out by humans. Kohonen's Self Organising Maps (Kohonen, Biol Cybern 43:59-69, 1982) algorithm is able to split a population into groups based on large and complex sets of observations. Once the population is split, the individual groups can then be probed for their defining characteristics providing insight into the rationale of the split. The characteristics identified form the basis of classification systems that are able to accurately predict which group an individual will belong to, using only a small subset of the tests available. The specifics of this methodology are detailed herein, and the resulting classification systems provide an effective tool to prognose the learning abilities of new subjects.

  19. Whole-body Vibration Exposure of Drill Operators in Iron Ore Mines and Role of Machine-Related, Individual, and Rock-Related Factors.

    Science.gov (United States)

    Chaudhary, Dhanjee Kumar; Bhattacherjee, Ashis; Patra, Aditya Kumar; Chau, Nearkasen

    2015-12-01

    This study aimed to assess the whole-body vibration (WBV) exposure among large blast hole drill machine operators with regard to the International Organization for Standardization (ISO) recommended threshold values and its association with machine- and rock-related factors and workers' individual characteristics. The study population included 28 drill machine operators who had worked in four opencast iron ore mines in eastern India. The study protocol comprised the following: measurements of WBV exposure [frequency weighted root mean square (RMS) acceleration (m/s(2))], machine-related data (manufacturer of machine, age of machine, seat height, thickness, and rest height) collected from mine management offices, measurements of rock hardness, uniaxial compressive strength and density, and workers' characteristics via face-to-face interviews. More than 90% of the operators were exposed to a higher level WBV than the ISO upper limit and only 3.6% between the lower and upper limits, mainly in the vertical axis. Bivariate correlations revealed that potential predictors of total WBV exposure were: machine manufacturer (r = 0.453, p = 0.015), age of drill (r = 0.533, p = 0.003), and hardness of rock (r = 0.561, p = 0.002). The stepwise multiple regression model revealed that the potential predictors are age of operator (regression coefficient β = -0.052, standard error SE = 0.023), manufacturer (β = 1.093, SE = 0.227), rock hardness (β = 0.045, SE = 0.018), uniaxial compressive strength (β = 0.027, SE = 0.009), and density (β = -1.135, SE = 0.235). Prevention should include using appropriate machines to handle rock hardness, rock uniaxial compressive strength and density, and seat improvement using ergonomic approaches such as including a suspension system.

  20. Market structure, industrial organisation and technological development: the case of the Japanese electronics-based nc-machine tool industry.

    OpenAIRE

    Watanabe, S

    1983-01-01

    ILO pub-WEP pub. Working paper on the impact of market structure and business organization on technological change in the automatic control machine tool industry in Japan - based on a 1982 sample survey of 40 industrial enterprises, discusses research and development trends, demand, production, subcontracting, competition, etc.; investigates the impact of electronics Innovation on small scale industry, the international division of labour and on developing countries. Bibliography and graphs.