WorldWideScience

Sample records for cardan shafts

  1. Investigate of Mechanical Fuse in Cardan Shaft Using FEM

    OpenAIRE

    Sayed Poorya Rabiei; Reza Azarafza

    2014-01-01

    A Cardan shaft is a mechanical component for transmitting torque and rotation, usually used to connect drive shaft to driven shaft that cannot be connected directly because of distance or the need to allow for relative movement between them. If overload is applied to cardan shaft, failure can occur in each part of the cardan shaft and maybe some irreparable damage occur to the cardan shaft. Thus it is important to investigate the existence of mechanical fuse in cardan shaft, and this subjcet ...

  2. Analytic solution of simplified Cardan's shaft model

    Directory of Open Access Journals (Sweden)

    Zajíček M.

    2014-12-01

    Full Text Available Torsional oscillations and stability assessment of the homokinetic Cardan shaft with a small misalignment angle is described in this paper. The simplified mathematical model of this system leads to the linearized equation of the Mathieu's type. This equation with and without a stationary damping parameter is considered. The solution of the original differential equation is identical with those one of the Fredholm’s integral equation with degenerated kernel assembled by means of a periodic Green's function. The conditions of solvability of such problem enable the identification of the borders between stability and instability regions. These results are presented in the form of stability charts and they are verified using the Floquet theory. The correctness of oscillation results for the system with periodic stiffness is then validated by means of the Runge-Kutta integration method.

  3. Real Time Cardan Shaft State Estimation of High-Speed Train Based on Ensemble Empirical Mode Decomposition

    OpenAIRE

    Cai Yi; Jianhui Lin; Tengda Ruan; Yanping Li

    2015-01-01

    Due to the special location and structure of transmission system on high-speed train named CRH5, dynamic unbalance state of the cardan shaft will pose a threat to the train servicing safety, so effective methods that test the cardan shaft operating information and estimate the performance state in real time are needed. In this study a useful estimation method based on ensemble empirical mode decomposition (EEMD) is presented. By using this method, time-frequency characteristic of cardan shaft...

  4. Real Time Cardan Shaft State Estimation of High-Speed Train Based on Ensemble Empirical Mode Decomposition

    Directory of Open Access Journals (Sweden)

    Cai Yi

    2015-01-01

    Full Text Available Due to the special location and structure of transmission system on high-speed train named CRH5, dynamic unbalance state of the cardan shaft will pose a threat to the train servicing safety, so effective methods that test the cardan shaft operating information and estimate the performance state in real time are needed. In this study a useful estimation method based on ensemble empirical mode decomposition (EEMD is presented. By using this method, time-frequency characteristic of cardan shaft can be extracted effectively by separating the gearbox vibration acceleration data. Preliminary analysis suggests that the pinions rotating vibration separated from gearbox vibration by EEMD can be used as important assessment basis to estimate cardan shaft state. With two sets gearbox vibration signals collected from the in-service train at different running speed, the comparative analysis verifies that the proposed method has high effectiveness for cardan-shaft state estimate. Of course, it needs further research to quantify the performance state of cardan shaft based on this method.

  5. Comparison between nose-suspended motors and cardan-shaft transmissions with hollow shafts; Vergleich Tatzlagerantrieb und Kardanantrieb mit Hohlwelle

    Energy Technology Data Exchange (ETDEWEB)

    Sebald, M.B. [Deutsche Bahn AG, Muenchen (Germany).Technik/Beschaffung

    2005-08-01

    In selecting the type of drive for an electric locomotive, operators can choose from several alternatives. The two most common variants today are nose-suspended motors and cardan-shaft transmissions using hollow shafts. As he commenced his research for this article, our author encountered numerous works discussing the relative pros and cons of these two types of drive but was struck by the paucity of publications attempting to present an overview from a combined technical and economic point of view. This is all the more astounding given that choosing a transmission system represents a key decision-making criterion clearly influencing the economics of operations. (orig.)

  6. Dynamic unbalance detection of cardan shaft in high-speed train based on EMD-SVD-NHT

    Institute of Scientific and Technical Information of China (English)

    丁建明; 林建辉; 何刘; 赵洁

    2015-01-01

    Contrary to the aliasing defect between the adjacent intrinsic model functions (IMFs) existing in empirical model decomposition (EMD), a new method of detecting dynamic unbalance with cardan shaft in high-speed train was proposed by applying the combination between EMD, Hankel matrix, singular value decomposition (SVD) and normalized Hilbert transform (NHT). The vibration signals of gimbal installed base were decomposed through EMD to get different IMFs. The Hankel matrix constructed through the single IMF was orthogonally executed through SVD. The critical singular values were selected to reconstruct vibration signs on the basis of the key stack of singular values. Instantaneous frequencys (IFs) of reconstructed vibration signs were applied to detect dynamic unbalance with shaft and eliminated clutter spectrum caused by the aliasing defect between the adjacent IMFs, which highlighted the failure characteristics. The method was verified by test data in the unbalance condition of dynamic cardan shaft. The results show that the method effectively detects the fault vibration characteristics caused by cardan shaft dynamic unbalance and extracts the nature vibration features. With comparison to the traditional EMD-NHT, clarity and failure characterization force are significantly improved.

  7. Influence of Axial Force in The Intermediate Shaft on the Load Capacity of the Paired Cardan Mechanism

    Directory of Open Access Journals (Sweden)

    Branimir Pavić

    2012-10-01

    Full Text Available The design of intermediate shaft with axially movablesplined joint must be adapted to the variable position of theshaft axis, i.e. to the change of the joint angle during operation.This design is also used for the reduction of axial forces whichare caused by inaccuracy in the production and assembling ofC(ll·dan mechanisms. The axial force which is generated by frictionof contact swfaces in the splined joint is the function of themagnitude of the transfeJTed torsion moments, splined dimensions,lubrication conditions, and materials used for contactswfaces. It will cause additional bearing loads at cross journalsand in the shaft supports, as well as unallowed vibrations andnoise during operation, thus affecting the safety and lifetime ofthe Cardan mechanism. The theoretical and empirical analysisof Cm·dan mechanisms, which have been studied with andwithout axial forces in the splinedjoint and its effect on durabilityof mechanism elements have been presented.

  8. Torsion Vibration Dynamics of Shafting System with Cardan Joints%十字轴万向节串联轴系扭转动力学分析

    Institute of Scientific and Technical Information of China (English)

    陈晓红; 董海军; 葛文杰; 柏龙

    2011-01-01

    利用集中质量分析法,视传动轴为弹性体、万向节为刚体,建立了十字轴万向节串联轴系扭振分析的等效模型.根据该等效模型,在考虑万向节的传动效率和传动轴的阻尼等条件下,推导了轴系的扭振分析动力学方程.在此基础上分析了中间传动轴刚度和轴间夹角分别对轴系振动角速度响应、传动精度和传动比的影响.通过实例对比分析了不同传动轴刚度和轴间夹角对串联轴系扭转振动影响.研究结果对用于飞机上的十字万向节串联轴系中如何降低轴系质量、减小扭振具有指导意义.%Based on concentration mass method, torsion vibration equivalent model of shafting system with multiple cardan joints is established, as well as torsion vibration dynamical equations of shafting system are presented by considering the transmission efficiency of cardan joints and the damper of transmission shafts. Accordingly, the effect of the stiffness of intermediate shafts and the angle between shafts on the response of shafting system angular velocity, the transmission accuracy and the transmission ratio are analyzed. Finally, the effect of different stiffness of shafts on shafting system is analyzed by instance solution. It provides theoretical references for keeping the torsion vibration of shafting systems used in aeroplane under restraint in its design, and for reducing the mass of driveline.

  9. A Calculation Model of Torsional Vibration of Cardan Shaft based on Constraint Equation%基于约束方程的十字万向轴扭转振动计算模型

    Institute of Scientific and Technical Information of China (English)

    张晓霞; 钟文生; 姚远

    2012-01-01

    A torsional vibration dynamic model of double - cardan shaft is established with tools of constraint e-quation and finite element method. Numerical simulation shows that angular accelerations of the model are identical with calculation results, verifying the correctness of double - cardan shaft. Trie fluctuation of mid - shaft due to comer angle of cardan and high frequencies of torsional vibration are considered in this model and it is suited for torsional vibration analysis of cardan shaft drive system.%万向轴传动由于附加力矩会对传动系统产生强迫振动,为了避开传动系统扭转共振,需要对万向轴传动系统进行计算分析,合理选取结构参数.利用约束方程表示万向铰传动特点,并用有限单元法建立双万向轴扭转振动动力学模型,通过数值仿真得到万向轴传动系统扭转振动数值解.计算结果表明:模型能够计算万向轴附加力矩引起的强迫振动,可用于万向轴传动系统扭转振动分析.

  10. Research of the CRH5 Cardan Shaft Roll Frequency Energy by EMD Method%基于EMD的CRH5动车组万向轴转频能量研究

    Institute of Scientific and Technical Information of China (English)

    阮腾达; 林建辉

    2014-01-01

    通过监测CRH5动车组齿轮箱振动,计算万向轴特征频率能量对评估万向轴状态具有现实意义。本文简述了经验模态分解(EMD)的基本方法,对实测200km/h下齿轮箱振动信号进行EMD分解,提取万向轴特征频率成分,并计算其能量。研究结果标明该方法可以有效对万向轴动不平衡进行评估。%Calculate CRH5 cardan characteristic frequency energy by monitoring the vibration of gearbox is meaningful to assess the state of the cardan shaft .This paper described the EMD method used to decompose the signal of gearbox vibration when the speed of train is 200km/h, extract characteristic frequency of the cardan shaft and calculate the energy .Research results show this method can evaluate the unbalance of cardan shaft ef-fectively.

  11. 十字轴万向节串联轴系支撑反力分析%Analyzing Support Reaction of Shaft System with a Series of Cardan Joints

    Institute of Scientific and Technical Information of China (English)

    陈晓红; 董海军; 葛文杰; 柏龙

    2011-01-01

    Using space mechanics analysis method, we analyze each cardan joint's additional torque caused by its inertial force in the transmission process of the shaft system with a series of cardan joints and establish the shaft system's mechanics model by taking its friction and inertial force into consideration. According to the mechanics mod- el, we discuss the effects of such parameters as distance of supports, distance of cardan joints at both ends of an intermediate transmission shaft without support, input torque and angle between shafts on the maximum support reaction of the shaft system and then contrast the effects of each parameter on the maximum support reaction when the shafts are installed in different ways.%采用空间力学方法,分析了十字轴万向节串联轴系在传动过程中各个万向节因惯性力而产生的附加扭矩。在考虑摩擦和惯性力的情况下,建立了十字轴万向节串联轴系的力学模型。分析了轴系中支撑距离、无支撑中间传动轴两端万向节距离、输入扭矩及轴间夹角等参数对轴系中最大支撑反力的影响,并对比分析了不同安装方式下各参数对最大支撑反力的影响。

  12. 螺杆钻具万向轴故障树模型及花瓣强度分析%Model of the Fault Tree of Screwdrill Cardan Shaft and Petal Strength Analysis

    Institute of Scientific and Technical Information of China (English)

    韩传军; 黄显萍; 王玮; 刘洋; 张杰

    2013-01-01

    The cardan shaft of screwdrill tends to fail. Therefore, the fault tree analysis method was applied to study its reliability. The fault tree model was established with the cardan shaft assembly failure as the top event. The ascending method was used to make a qualitative analysis of 14 minimal cut sets of the tree. The finite element method was used to conduct a strength analysis of petal-type cardan shaft under the combined action of compression and torsion. The findings show that the petal root and the minimum cross-section are of high stress zone and they are subject to fracture failure most easily. The preciseness of the finite element analysis was verified through comparison with the field failure example.%针对螺杆钻具中易发生失效的万向轴部分,应用故障树分析方法对其可靠性进行了研究.建立以万向轴总成失效为顶事件的故障树模型,采用“上行法”定性分析了故障树的14个最小割集.利用有限元法对压扭组合作用下的花瓣式万向轴进行了强度分析,分析结果表明,花瓣的根部和最小截面处为高应力区,最易发生断裂失效.通过与现场失效实例对比,验证了有限元分析方法的正确性.

  13. 辅助工装的设计与万向轴法兰叉头端面齿的加工方法%The Design of Assistant Equipment and Manufacturing Method of the Cardan Shaft Flange Fork Gearing

    Institute of Scientific and Technical Information of China (English)

    刘体龙; 李秋生; 李蒙

    2016-01-01

    According to the characters of the cardan shaft flange fork gearing, an assistant equipment was designed which could be used to manufacture the flange fork gearing in a six-gear method without changing the structure of X6142A universal lifting platform milling machine ( or the X5042A vertical lifting milling machine) .%针对万向轴法兰叉头端面齿形结构的特点,设计了一种辅助工装,利用该工装,在不改变X6142A万能升降台(或X5042A立式升降台)铣床本身结构的基础上即可对法兰叉头端面齿同时进行六齿加工。

  14. Detection of the dynamic imbalance of cardan shaft by applying an improved DTCWT-SVD%万向轴动不平衡检测的改进 DTCWT-SVD 方法

    Institute of Scientific and Technical Information of China (English)

    何刘; 林建辉; 刘新厂; 黄衍

    2016-01-01

    针对经典小波和双树复小波(Dual-Tree Complex Wavelet Transform,DTCWT)频率泄露和混叠的根本缺陷,提出改进 DTCWT 算法,该算法解决了经典小波存在负频率以及经典小波和 DTCWT 滤波器频率不完全截止问题。将改进 DTCWT 算法和奇异值分解(Singular Value Decomposition,SVD)引入到万向轴动不平衡检测中,该方法的核心是:对万向节安装机座的振动信号进行改进 DTCWT 变换得到不同尺度的分解信号,对低频近似信号进行奇异值分解,以奇异值关键叠层作为奇异值的选择准则对信号进行重构,应用重构信号的傅里叶谱来检测高速列车万向轴的动不平衡。该方法在消除经典小波变换和 DTCWT 频率混叠的同时提高谱线清晰度,凸显故障特征。应用万向轴动不平衡试验数据对该方法进行试验验证,结果表明:改进 DTCWT-SVD 能够很好提取出万向轴动不平衡故障特征频率的基频、倍频,与经典小波、DTCWT、纯改进 DTCWT 相比,该方法在谱的清晰度和故障表征力上得到了显著提高。%A new improved algorithm of the dual tree complex wavelet transform (DTCWT)was proposed aiming at dealing with the leakage frequency and aliasing defect existing in classical wavelet transform and coventional DTCWT.The algorithm solves the problem of negative frequencies existing in classic wavelet and the problem of incomplete cut-off of filter frequency in classical wavelet transform and conventional DTCWT.The improved DTCWT and singular value decomposition (SVD)were introduced in the dynamic imbalance detection of cardan shaft.The vibration signals at the base installed with gimbal were decomposed through the improved DTCWT to get the different scale decomposition signal. The low-frequency approximated signal was decomposed by the SVD and the key singular values were selected to reconstruct the vibration signal based on the key stack of singular

  15. 热模锻传动轴滑动轴承承载力分析%Analysis on the Load Capacity of Slip Bearing for Cardan Shaft of Hot Die Forging Press

    Institute of Scientific and Technical Information of China (English)

    魏田华; 殷文齐; 杜建伟

    2015-01-01

    The essay introduces the Reynolds equation used to calculate the load capacity of oil film of slip bearing which is in dynamic pressure and radial type for the cardan shaft of the hot die forging press. The key dimension of the bearing is designed by Reynolds model. The finite element model is created based upon such dynamic pressure and radial slip bearing, the result of which analyse the pressure distribution on the oil film and variation of load capacity under different minimum oil film thickness. It concludes the maximum load capacity and the corresponding different minimum oil film thickness.%介绍用于动压径向滑动轴承油膜承载能力计算的雷诺方程。根据雷诺计算模型确定某热模锻压机传动轴滑动轴承的关键尺寸,并以该动压径向滑动轴承为基础,建立有限元模型,分析在不同最小油膜厚度下油膜上的压力分布和承载力变化,分析得出滑动轴承的最大承载能力及其所对应的最小油膜厚度。

  16. 高速列车万向轴动不平衡检测的EEMD-Hankel-SVD方法%Detection of the Dynamic Imbalance with Cardan Shaft in High-speed Train Applying EEMD-Hankel-SVD

    Institute of Scientific and Technical Information of China (English)

    丁建明; 林建辉; 赵洁

    2015-01-01

    A new method of detecting dynamic imbalance with cardan shaft in the high-speed train is proposed applying the combination between ensemble empirical model decomposition(EEMD), Hankel matrix and singular value decomposition(SVD) contrary to the aliasing defect between the adjacent intrinsic model functions existing in the EEMD. The vibration acceleration signals of gimbal are decomposed through EEMD to get the different intrinsic model components. The Hankel matrix, which is constructed throng the single decomposition model component, is orthogonally executed through SVD. The key singular values are selected to reconstruct vibration signs on the base of the key stack of singular values. Fourier spectrum of the reconstructed signal is applied to detect dynamic imbalance with shaft and eliminates clutter spectrum caused by the aliasing defect between the adjacent intrinsic model functions, highlights the failure characteristics. The method is verified by test data in the condition of dynamic imbalance, the results show this method can effectively detect the fault vibration characteristics caused by cardan shaft dynamic imbalance and extract the nature vibration features. With comparison to the simple EEMD, the clarity and failure characterization force are significantly improved.%针对聚合经验模式分解(Ensemble empirical model decomposition, EEMD)的等效滤波特性依然存在模式分量间频带重叠较大的根本缺陷,提出一种高速列车万向轴动不平衡动态检测的新方法.该方法的核心是对万向节安装机座的振动信号进行EEMD分解得到基本模式分量,应用基本模式分量信号来构造Hankel矩阵,对该矩阵进行正交化奇异值(Singular value decomposition, SVD)分解,以奇异值关键叠层作为奇异值的选择准则对信号进行重构,应用重构信号的傅里叶谱来检测高速列车万向轴的动不平衡,消除 EEMD 分解模式频带重叠对故障特征的淹没和混淆效应,提高了

  17. Transverse vibration of a rotor system driven by two cardan joints

    Science.gov (United States)

    Saigo, M.; Iwatsubo, T.

    1987-05-01

    The torque-induced transverse vibration of a rotor system driven by two Cardan joints is analyzed and the effects of the stiffness asymmetry of the rotor shaft supports, the damping force in the joints and the gyroscopic moment of the rotor on the dynamic stability of the system are evaluated. The analysis proves that both parametric and self-excited vibrations can occur due to the transmitted torque when the driving shaft and the driven shaft (rotor shaft) are inclined; the stiffness asymmetry of rotor supports does not always have the stabilizing effect which has been observed in a rotor system driven by a single Cardan joint [1

  18. Axial measuring system of passenger car cardan shaft for test bench and road experiments. Axialkraft-Messsystem fuer PKW-Gelenkwellen im Pruefstands- und Fahrversuch

    Energy Technology Data Exchange (ETDEWEB)

    Biermann, J.W. (Inst. fuer Kraftfahrwesen, Aachen (Germany)); Ganzmann, R. (Forschungsgesellschaft Kraftfahrwesen mbH, Aachen (Germany))

    1991-01-01

    The stimulation of vibrations by periodically alternating forces of homocinetic slip joints, particularly in cars with front-wheel drives, can lead to a loss in comfort. For the evaluation and further development of shafts, the detection of these alternating forces by measuring procedures on the test bench and in road experiments is required. For this purpose, the Forschungsgesellschaft Kraftfahrwesen Aachen (research society for motor vehicles in Aachen), fka, has developed a measuring system which facilitates an on-line indication of the periodical axial forces of displaceable joints in dynamic operation mode. (orig./HW)

  19. Transverse vibration of a rotor system driven by a Cardan joint

    Science.gov (United States)

    Iwatsubo, T.; Saigo, M.

    1984-07-01

    The transverse vibration of a rotor system driven by a Cardan joint is analyzed and the effect of the transmitted torque on the dynamic stability of the system evaluated. As a result of the analysis, the following facts are proved: when the driving shaft and driven shaft (rotor shaft) are included, both parametric and self-excited vibrations arise due to transmitted torque; asymmetrical stiffness of the rotor supports has the effect of stabilizing this self-excited vibration.

  20. Equipment for removing and refitting resilient packing in a cardan joint on the sea bed

    Energy Technology Data Exchange (ETDEWEB)

    Tuson, S.P.R.

    1983-06-08

    Equipment for removing and refitting resilient packing in a cardan joint at the base of a platform or column mounted on the sea bed, the cardan joint connected a pipe in the sea bed with a pipe leading up the column, said packing comprising a stack of rubber rings and metallic washers disposed between end plates and capable of being deformed in torsion and said packing being compressed between an abutment on the end of a hollow shaft in the cardan joint and an abutment on the adjacent end of a pipe. The equipment, comprising a casing, a carriage movable along guides on the casing, and a fork-shaped gripper mounted on the carriage, is provided with hooks adapted to secure the casing to the cardan joint, and drive means operable to move the carriage so that the gripper embraces the packing when the casing is secured to the cardan joint, said gripper including power operated pinchers having jaws arranged to engage lugs on the end plates of the packing and operable to force the end plates towards one another to compress the packing and reduce the overall length of the packing. 6 drawings.

  1. 基于 EMD-Hankel-SVD 的高速列车万向轴动不平衡检测%Detection of dynamic imbalance due to cardan shaft in high-speed train based on EMD-Hankel-SVD method

    Institute of Scientific and Technical Information of China (English)

    丁建明; 王晗; 林建辉; 黄晨光

    2015-01-01

    针对EMD(Empirical Model Decomposition)存在模式频率混叠带来的频谱杂乱的根本缺陷,提出一种高速列车万向轴动不平衡动态检测的新方法。该方法的核心是:对万向节安装机座的振动信号进行 EMD 分解得到基本模式分量,应用基本模式分量信号来构造 Hankel 矩阵,对该矩阵进行奇异值正交化分解,以奇异值关键叠层作为奇异值的选择准则对信号进行重构,应用重构信号的傅里叶谱来检测高速列车万向轴的动不平衡,消除 EMD 分解模式频率混叠带来频谱杂乱,提高了谱的清晰度,凸显了故障特征。应用万向轴动不平衡试验数据对该方法进行试验验证,结果表明:该方法能够有效检测万向轴动不平衡引起故障特征和万向轴的固有振动特性,与纯 EMD 方法相比,该方法在谱的清晰度和故障表征力上得到了显著提高。%A new method of detecting dynamic imbalance due to cardan shaft in high-speed train was proposed applying a synthesized method of EMD (Empirical Modal Decomposition),Hankel matrix and SVD (singular value decomposition)against the aliasing defect between adjacent intrinsic model functions existing in EMD.The vibration signals of gimbal installed base were decomposed through EMD to get the different intrinsic model components.The Hankel matrix,constructed of the single decomposition model components,was orthogonally decomposed through SVD and the key singular values were selected to reconstruct the vibration signal on the base of the key stack of singular values.The Fourier spectrum of the reconstructed signal was applied to detect dynamic imbalance of shaft and the clutter spectrum caused by the aliasing defect between adjacent intrinsic model functions was eliminated so as to highlight the failure characteristics.The method was verified by test data in the condition of dynamic imbalance.The results show the method can effectively detect the

  2. CALCULATION OF CONTACT TENSIONS IN CONJUGATE SURFACES IN SPHERE GLOBOIDAL RUSK SYNCHRONOUS CARDAN HINGE

    Directory of Open Access Journals (Sweden)

    A. M. Saniotsky

    2015-01-01

    Full Text Available The paper presents  a calculation of contact tensions between conjugate surfaces in sphere globoidal rusk synchronous cardan hinge on the condition that there is power balance at the constant torque on the output shaft. The required torque effect on the intake shaft at the constant angular velocity  has been calculated with the help of the Hertz’s theory of contact deformations . The maximum contact pressure has been ascertained through the torque which determines strength of the cardan hinge, its durability, wear rate in  the conjugate friction pair. The paper investigates transmission dependence of the maximum torque while changing  material quality and according to various typical sizes of the cardan hinge. Dependences of the calculated maximum torque value on material strength have been demonstrated graphically  in the logarithmic coordinate system.  A formula for maximum contact pressure value has been derived and it determines  strength of the hinge mechanism, its durability and wear rate  in the conjugate friction pair.The effect of geometrical relationship between a spherical cam radius and a globoidal  surface radius of a hinge contact has been determined with the purpose to analyze optimal design parameters of the sphere globoidal rusk synchronous cardan hinge. It has been established that permissible torque in the hinge mechanism grows with a quadratic dependence while increasing a cam radius and  the torque is proportionally growing while increasing an axis radius of globoidal rusk surface on which spherical cams are set. The maximum permissible torque value grows with a cubic dependence while using qualitative material with thermally treated surface and application of lubrication materials which tolerates significant (up to [σ] = 1000 MPa contact loads.  Two-fold increase of typical size of the sphere globoidal rusk synchronous cardan hinge leads to an 8-fold increase of the permissible transmitted torque.

  3. Control of quadriaxial cardan suspension

    Science.gov (United States)

    Novozhilov, I. V.

    1984-04-01

    A quadriaxial Cardan suspension is to be servomechanically controlled so as to stabilize a definite orientation of the platform during arbitrary motion of the frame. The problem is solved with the use of five orthogonal systems of coordinates tied one to the platform, one to each of the three gimbals, and one to the frame respectively. The suspension is assumed to be structurally perfectly rigid and to be part of a gyroscopic indicator-stabilization system. The corresponding dynamic equations are written as equations for angular momenta and several variants of control, for the various rotations, are constructed. One such variant, a more intricate one, is course-vertical control. Dynamic control of the suspension in a stationary frame, to ensure any arbitrarily prescribed angular evolutions of the platform, is also considered and the procedure for constructing such a control is outlined.

  4. Vibration Control of Tower Structure with Multiple Cardan Gyroscopes

    Directory of Open Access Journals (Sweden)

    Haoxiang He

    2017-01-01

    Full Text Available Tower structure is sensitive to hurricane and earthquake, and it is easy to generate large deflection and dynamic response. The multiple cardan gyroscope has two rotational degrees of freedom, which can generate strong moments to constrain the two horizontal orthogonal deflections if the rotor operates in high speeds, so the structural dynamic responses can be decreased. Hence, the method of dynamic control of the tower structure under wind load and earthquake action is proposed by using the multiple cardan gyroscopes as the dampers. The dynamic mechanism and the fixed axis principle of the multiple cardan gyroscope are introduced, and the dynamic equation of the gyroscope is established. The damping mechanism of the gyroscope is also described. For the tower structure equipped with the multiple cardan gyroscope dampers, the multidimensional control equation considering torsion effect is established, and the equivalent state space equation is presented. Taking a TV Tower with a number of gyroscope dampers as an analysis example, the structural dynamic responses and damping performance under fluctuating wind loads and earthquake action is studied. The results show that the multiple cardan gyroscope dampers with suitable parameters can effectively decrease the structural vibration in horizontal directions and torsional direction.

  5. Reliability of agriculture universal joint shafts based on temperature measuring in universal joint bearing assemblies

    Energy Technology Data Exchange (ETDEWEB)

    Asonja, A.; Desnica, E.

    2015-07-01

    This paper presents a research into reliability calculations of agriculture double universal joint shafts based on temperature measuring in cardan-type universal joint bearing assemblies. Special laboratory equipment was developed for this research which is presented in the paper. The objective of this research was to test the real life span of universal joint shafts in the laboratory and in field, to obtain the results which can be used to improve the reliability of universal joint shafts. If the presented research were used along with maintenance measures recommended in the paper and with proper use, the level of reliability of the shafts would be 2.1 times higher. The presented results of the research showed that needle bearings, i.e. bearing assemblies of the joints, are the most critical elements on universal joint shafts and are possible causes of their lower reliability. The second universal joint is the part with the lowest reliability in the observed technical system. . (Author)

  6. Vibration Control of Tower Structure with Multiple Cardan Gyroscopes

    OpenAIRE

    Haoxiang He; Xin Xie; Wentao Wang

    2017-01-01

    Tower structure is sensitive to hurricane and earthquake, and it is easy to generate large deflection and dynamic response. The multiple cardan gyroscope has two rotational degrees of freedom, which can generate strong moments to constrain the two horizontal orthogonal deflections if the rotor operates in high speeds, so the structural dynamic responses can be decreased. Hence, the method of dynamic control of the tower structure under wind load and earthquake action is proposed by using the ...

  7. Cardan gear mechanism versus slider-crank mechanism in pumps and engines

    Energy Technology Data Exchange (ETDEWEB)

    Karhula, J.

    2008-07-01

    In machine design we always want to save space, save energy and produce as much power as possible. We can often reduce accelerations, inertial loads and energy consumption by changing construction. In this study the old cardan gear mechanism (hypocycloid mechanism) has been compared with the conventional slider-crank mechanism in air pumps and four-stroke engines. Comprehensive Newtonian dynamics has been derived for the both mechanisms. First the slidercrank and the cardan gear machines have been studied as lossless systems. Then the friction losses have been added to the calculations. The calculation results show that the cardan gear machines can be more efficient than the slider-crank machines. The smooth running, low mass inertia, high pressures and small frictional power losses make the cardan gear machines clearly better than the slider-crank machines. The dynamic tooth loads of the original cardan gear construction do not rise very high when the tooth clearances are kept tight. On the other hand the half-size crank length causes high bearing forces in the cardan gear machines. The friction losses of the cardan gear machines are generally quite small. The mechanical efficiencies are much higher in the cardan gear machines than in the slider-crank machines in normal use. Crankshaft torques and power needs are smaller in the cardan gear air pumps than in the equal slider-crank air pumps. The mean crankshaft torque and the mean output power are higher in the cardan gear four-stroke engines than in the slider-crank four-stroke engines in normal use. The cardan gear mechanism is at its best, when we want to build a pump or an engine with a long connecting rod (approx 5.crank length) and a thin piston (approx 1.5.crank length) rotating at high angular velocity and intermittently high angular acceleration. The cardan gear machines can be designed also as slide constructions without gears. Suitable applications of the cardan gear machines are three-cylinder half

  8. Optimum computer design of a composite cardan shaft according to the criteria of cost and weight

    Science.gov (United States)

    Nepershin, R. I.; Klimenov, V. V.

    1987-07-01

    A successive unconditional minimization algorithm using penalty functions without calculation of derivatives is an efficient approach to the computerized optimization of structural elements of hybrid composites with regard to cost and weight, given a small number of design variables and uncomplicated calculation of the objective function and limitations.

  9. Charge transport through a cardan-joint molecule.

    Science.gov (United States)

    Ruben, Mario; Landa, Aitor; Lörtscher, Emanuel; Riel, Heike; Mayor, Marcel; Görls, Helmar; Weber, Heiko B; Arnold, Andreas; Evers, Ferdinand

    2008-12-01

    The charge transport through a single ruthenium atom clamped by two terpyridine hinges is investigated, both experimentally and theoretically. The metal-bis(terpyridyl) core is equipped with rigid, conjugated linkers of para-acetyl-mercapto phenylacetylene to establish electrical contact in a two-terminal configuration using Au electrodes. The structure of the [Ru(II)(L)(2)](PF(6))(2) molecule is determined using single-crystal X-ray crystallography, which yields good agreement with calculations based on density functional theory (DFT). By means of the mechanically controllable break-junction technique, current-voltage (I-V), characteristics of [Ru(II)(L)(2)](PF(6))(2) are acquired on a single-molecule level under ultra-high vacuum (UHV) conditions at various temperatures. These results are compared to ab initio transport calculations based on DFT. The simulations show that the cardan-joint structural element of the molecule controls the magnitude of the current. Moreover, the fluctuations in the cardan angle leave the positions of steps in the I-V curve largely invariant. As a consequence, the experimental I-V characteristics exhibit lowest-unoccupied-molecular-orbit-based conductance peaks at particular voltages, which are also found to be temperature independent.

  10. [Hair shaft anomalies].

    Science.gov (United States)

    Itin, P H

    1997-06-01

    Hair shaft disorders lead to brittle and uncombable hair. As a rule the hair feels dry and lusterless. Hair shaft abnormalities may present as localized of generalized alterations. Genetic predisposition and exogenous factors are able to produce hair shaft abnormalities. The most important examination to analyze a hair shaft problem is light microscopy. Treatment of hair shaft disorders should focus on the cause. In addition, minimizing traumatic influences to hair shafts, such as electric dryer, permanent waves and dyes is important.

  11. Analysis of the moment caused by friction of cardan joint. Cardan joint no friction kishinryoku kaiseki

    Energy Technology Data Exchange (ETDEWEB)

    Ono, K.; Yagi, Shida, T. (Atsugi Unisia Corp., Kanagawa (Japan))

    1990-10-01

    Analyzing the vibromotive force, generated by the friction, in generation morphology, level, dynamical characteristics, etc., through measurement of joint unit friction simulation of frictional vibromotive force and on-platform measurement of propeller shaft in vibromotive force, the present report investigated the influence of friction on the vehicle in sound vibration performance. By a vibromotive force measurement system, internally equipped with a piezoelectric type force meter, frictional vibromotive force could be quantitatively grasped. The friction must be appropriately controlled, because the moment, generated by it, is expected to be put in the vehicle by intermediation of a supporting point and adversely influence the sound vibration performance. Apart from the above, elucidation was made of relation between the ordinal number components of rotation of vibromotive force and friction, calculation of reaction force at the supporting point by the frictional measurement, relation between the joint angle and frictional vibromotive force, second couple force due to the friction, etc. 3 refs., 15 figs.

  12. [Hair shaft abnormalities].

    Science.gov (United States)

    Itin, P H; Düggelin, M

    2002-05-01

    Hair shaft disorders may lead to brittleness and uncombable hair. In general the hair feels dry and lusterless. Hair shaft abnormalities may occur as localized or generalized disorders. Genetic predisposition or exogenous factors are able to produce and maintain hair shaft abnormalities. In addition to an extensive history and physical examination the most important diagnostic examination to analyze a hair shaft problem is light microscopy. Therapy of hair shaft disorders should focus to the cause. In addition, minimizing traumatic influences to hair shafts, such as dry hair with an electric dryer, permanent waves and dyes is important. A short hair style is more suitable for such patients with hair shaft disorders.

  13. THE GROUNDING OF THE STRUCTURAL PARAMETERS OF THE AREAHLOBOYID RUSK SYNCHRONOUS CARDAN HINGE

    Directory of Open Access Journals (Sweden)

    A. Saniotskyi

    2015-02-01

    Full Text Available The method of calculation of structural parameters of the areahloboyid rusk synchronous cardan hinge with consideration of contact tensions in the mating surfaces is determined, the required torque in the input wave with a contact by using the Hertz’s theory of contact deformations is determined. The dependence of the maximum torque for different hyposizes of the cardan hinge is investigated. The dependences of the calculated maximum torque to the resistance of the material are demonstrated graphically in the logarithmic coordinate system.

  14. Reliability of agriculture universal joint shafts based on temperature measuring in universal joint bearing assemblies

    Directory of Open Access Journals (Sweden)

    Аleksandar Asonja

    2015-03-01

    Full Text Available This paper presents a research into reliability calculations of agriculture double universal joint shafts based on temperature measuring in cardan-type universal joint bearing assemblies. Special laboratory equipment was developed for this research which is presented in the paper. The objective of this research was to test the real life span of universal joint shafts in the laboratory and in field, to obtain the results which can be used to improve the reliability of universal joint shafts. If the presented research were used along with maintenance measures recommended in the paper and with proper use, the level of reliability of the shafts would be 2.1 times higher. The presented results of the research showed that needle bearings, i.e. bearing assemblies of the joints, are the most critical elements on universal joint shafts and are possible causes of their lower reliability. The second universal joint is the part with the lowest reliability in the observed technical system.

  15. Steerable shaft drilling

    Energy Technology Data Exchange (ETDEWEB)

    Pigott, C.P. (Pigott Shaft Drilling Ltd., Preston (UK))

    1990-03-01

    The paper outlines the techniques of steerable shaft drilling and gives brief details of the various machines currently available to carry out this task. It summarizes the many potential benefits of using this method, which could lead to more mines having multiple shafts, each serving a specific purpose. 8 figs.

  16. FACTORS EFFECTTING ON FAILURE AT CARDAN COUPLINGS AND PRECAUTIONS WHICH MUST BE TAKEN

    Directory of Open Access Journals (Sweden)

    Mehmet UÇAR

    1999-02-01

    Full Text Available In this study, failures caused by bad usage during operation and by manufacturing are examined. Failures occurred on cardan coupling are analyzed by using of photographs which have been taken. As not to be occurred any failures on cardan coupling before its usage life, it has been seen that system must not be over loaded, exact oiling in areas which have relative motion must be used, oil used must have high performance at both low and high temperature (- 30 o C, 120 o C, cross pin and needle bearing must have high strength against to wear and shock loads, internal strength on the areas which have been connected by welding must be decreased and coupling must be balanced as statically and dynamic.

  17. Influence of the helical and six available Cardan sequences on 3D ankle joint kinematic parameters.

    Science.gov (United States)

    Sinclair, J; Taylor, P J; Edmundson, C J; Brooks, D; Hobbs, S J

    2012-09-01

    Cardan/Euler and helical angles are the popular methods of quantifying angular kinematics. Cardan angles are sequence dependent and crosstalk can influence the kinematic calculations. The International Society of Biomechanics (ISB) recommends a sagittal, coronal, and then transverse (XYZ) sequence of rotations, although it has been proposed that when calculating rotations outside of the sagittal plane, this may not be the most appropriate method. This study investigated the influence of the helical and six available Cardan sequences on three-dimensional (3D) ankle joint kinematics. Kinematic data were obtained using an eight-camera motion analysis system as participants ran at 4.0 m/s +/- 5%. Repeated measures ANOVAs were used to compare kinematic parameters, and intraclass correlations were employed to identify evidence of crosstalk across planes. The results indicate that in the transverse and coronal planes, peak angle and range of motion values using the YXZ and ZXY sequences were significantly greater than the other sequences. Furthermore, utilization of YXZ and ZXY sequences was associated with the strongest correlations from the sagittal plane, and the XYZ sequence was found to be associated with the lowest correlations. It appears that for the representation of 3D ankle joint kinematics, the XYZ sequence is associated with minimal planar crosstalk and as such its use is encouraged.

  18. Flexible Coupling Corrects Shaft Misalinements

    Science.gov (United States)

    Mayo, R. A.

    1983-01-01

    Proposed flexible coupling provides nearly error free measurements of shaft rotation in presence of misalinements between shaft and position sensing transducer. Intended to be used in situations in which input or output shaft is mounted on flexible joint. Its function is to insure equal input and output angular velocities by forcing input and output shafts to remain parallel.

  19. The Cardan Shaft Driving and High Speed Trains%万向轴驱动和高速列车

    Institute of Scientific and Technical Information of China (English)

    陆冠东

    2007-01-01

    万向轴驱动装置不单被应用于内燃动车组,更是高速电力机车和电动车组(200 km/h~300 km/h)不可或缺的重要部件.文章介绍了万向轴驱动装置在高速列车和电动车组上的应用.

  20. The effect of differing Cardan angle sequences on three dimensional lumbo-pelvic angular kinematics during running.

    Science.gov (United States)

    Schache, A G; Wrigley, T V; Blanch, P D; Starr, R; Rath, D A; Bennell, K L

    2001-09-01

    The variability in the three dimensional (3D) lumbo-pelvic angular kinematic patterns during running when using differing Cardan angle sequences was quantified. Data for four able-bodied subjects running on a treadmill at 4.0 m/s were captured using a motion analysis system with six cameras operating at 200 Hz. The adjusted coefficient of multiple correlation was used to compare graphical waveforms whilst the maximum root mean square of the differences was used to express the magnitude of any discrepancy in absolute units. Minimal qualitative differences were found between the various sequences. Quantitative differences between each of the Cardan angle sequences were not found to exceed 7.0 degrees and 2.8 degrees for the lumbar spine and pelvic rotations respectively. It was concluded that different Cardan angle sequences were not found to substantially affect typical 3D lumbo-pelvic angular kinematic patterns during running.

  1. ON THE MOVEMENTS OF A STATICALLY BALANCED GYROSCOPE IN A CARDAN JOINT, MOUNTED ON A VIBRATING BASE

    Science.gov (United States)

    A translation of a Soviet technical article entitled ’’On the Movements of a Statically Balanced Gyroscope in a Cardan Joint, Mounted on a Vibrating Base’’ is presented. The article is a mathematical treatment of the subject.

  2. Tibial shaft fracture

    DEFF Research Database (Denmark)

    Larsen, Peter

    IV also showed a significant worse outcome in 3 of the 5 KOOS subscales compared to a reference population at 12-months follow-up. Moreover, this study showed that increasing difference in muscle strength for knee extension between legs was associated with a decreasing QOL. The results of this thesis...... suggested that regaining pre injured QOL and muscle strength following a tibial shaft fracture takes considerable time....

  3. Pneumatic flexible shaft couplings

    OpenAIRE

    2007-01-01

    Main effort of every design engineer is reduction of torsional oscillation in any mechanical system. At present this problem can be solved by means of a suitable modification of dynamic properties of flexible shaft couplings according to dynamics in the given systems. But the dynamic properties of nowadays-applied flexible couplings arenot unchangeable because of aging and fatigue processes occurring in flexible coupling elements. Result of this fact causes detuning of mechanical system. Taki...

  4. FRACTURE SHAFT HUMERUS: INTERLOCKING

    Directory of Open Access Journals (Sweden)

    Deepak Kaladagi

    2014-12-01

    Full Text Available BACKGROUND: The incidence of humeral fracture has significantly increased during the present years due to the population growth and road traffic, domestic, industrial, automobile accidents & disasters like tsunami, earthquakes, head-on collisions, polytrauma etc. In order to achieve a stable fixation followed by early mobilization, numerous surgical implants have been devised. PURPOSE: The purpose of this study is to analyze the results of intramedullary fixation of proximal 2/3rd humeral shaft fractures using an unreamed interlocking intramedullary nail. INTRODUCTION: In 40 skeletally matured patients with fracture shaft of humerus admitted in our hospital, we used unreamed antegrade interlocking nails. MATERIAL: We carried out a prospective analysis of 40 patients randomly selected between 2001 to 2014 who were operated at JNMC Belgaum, MMC Mysore & Navodaya Medical College, Raichur. All cases were either RTAs, Domestic, Industrial, automobile accidents & also other modes of injury. METHOD: Routine investigations with pre-anaesthetic check-up & good quality X-rays of both sides of humerus was taken. Time of surgery ranged from 5-10 days from the time of admission. Only upper 1/3rd & middle 1/3rd humeral shaft fractures were included in the study. In all the cases antegrade locked unreamed humeral nails were inserted under C-arm. Patient was placed in supine position & the shoulder was kept elevated by placing a sandbag under the scapula. In all patients incision taken from tip of acromion to 3cm over deltoid longitudinally. Postoperatively sling applied with wrist & shoulder movements started after 24 hours. All the patients ranged between the age of 21-50 years. RESULTS: Total 40 patients were operated. Maximum fracture site were in the middle third- 76%, 14% upper 1/3rd. All 40 patients achieved union. The average time of union was 8-10 weeks. All patients regained full range of movements except in few cases, where there was shoulder

  5. [Humeral shaft fractures].

    Science.gov (United States)

    Schittko, A

    2004-08-01

    Since Lorenz Böhler postulated in his 1964 summary with the title "Against the operative treatment of fresh humeral shaft fractures" that the operative treatment is the exception in the therapy of humeral fractures times have changed. In the last years a conservative treatment of a humeral fracture is the exception and only used after straight indications. The operative therapy nowadays is the gold standard because of the development of new intramedullar and rotation stable implants in addition to the classical osteosynthesis with the plate. But even the external fixator for primary stabilisation in polytrauma patients or as rescue procedure after complications should be in repertory of every orthopedic surgeon. Attention should be put on the avoidance of primary and the correct treatment of secondary nerval lesions, esp. of the radial nerve. Here we are tending to the operative revision of the nerve in indistinct cases. In the treatment of the seldom humeral shaft fracture of the child conservative treatment is to prefer; in complications a resolute shift to a final operative stabilisation of the fracture is necessary.

  6. [Approaches to radial shaft].

    Science.gov (United States)

    Bartoníček, J; Naňka, O; Tuček, M

    2015-10-01

    In the clinical practice, radial shaft may be exposed via two approaches, namely the posterolateral Thompson and volar (anterior) Henry approaches. A feared complication of both of them is the injury to the deep branch of the radial nerve. No consensus has been reached, yet, as to which of the two approaches is more beneficial for the proximal half of radius. According to our anatomical studies and clinical experience, Thompson approach is safe only in fractures of the middle and distal thirds of the radial shaft, but highly risky in fractures of its proximal third. Henry approach may be used in any fracture of the radial shaft and provides a safe exposure of the entire lateral and anterior surfaces of the radius.The Henry approach has three phases. In the first phase, incision is made along the line connecting the biceps brachii tendon and the styloid process of radius. Care must be taken not to damage the lateral cutaneous nerve of forearm.In the second phase, fascia is incised and the brachioradialis identified by the typical transition from the muscle belly to tendon and the shape of the tendon. On the lateral side, the brachioradialis lines the space with the radial artery and veins and the superficial branch of the radial nerve running at its bottom. On the medial side, the space is defined by the pronator teres in the proximal part and the flexor carpi radialis in the distal part. The superficial branch of the radial nerve is retracted together with the brachioradialis laterally, and the radial artery medially.In the third phase, the attachment of the pronator teres is identified by its typical tendon in the middle of convexity of the lateral surface of the radial shaft. The proximal half of the radius must be exposed very carefully in order not to damage the deep branch of the radial nerve. Dissection starts at the insertion of the pronator teres and proceeds proximally along its lateral border in interval between this muscle and insertion of the supinator

  7. Analysis of movement of non-cardan joint axial piston pump

    Energy Technology Data Exchange (ETDEWEB)

    Song Qi; Xue Xiaoping

    1984-01-01

    It is difficult to study kinematics of a non-cardan joint axial piston pump due to complexity of its mechanism movement. The current calculation method is tedious and movement of the pump with several parameters cannot be easily analyzed. However, these parameters can be calculated continuously and accurately by computers using the relevant equations. Examples are analyzed by the proposed method. It shows that selection of adequate geometric parameters is virtually a problem of optimizing the structural parameters by taking into account all the relevant parameters. Sufficient attention should be given to the parameter representing the angle between the connection rod and the axis of the piston. The structural parameters of variable and fixed displacement pumps should be dealt with individually.

  8. Laser shaft alignment measurement model

    Science.gov (United States)

    Mo, Chang-tao; Chen, Changzheng; Hou, Xiang-lin; Zhang, Guoyu

    2007-12-01

    Laser beam's track which is on photosensitive surface of the a receiver will be closed curve, when driving shaft and the driven shaft rotate with same angular velocity and rotation direction. The coordinate of arbitrary point which is on the curve is decided by the relative position of two shafts. Basing on the viewpoint, a mathematic model of laser alignment is set up. By using a data acquisition system and a data processing model of laser alignment meter with single laser beam and a detector, and basing on the installation parameter of computer, the state parameter between two shafts can be obtained by more complicated calculation and correction. The correcting data of the four under chassis of the adjusted apparatus moving on the level and the vertical plane can be calculated. This will instruct us to move the apparatus to align the shafts.

  9. Pneumatic flexible shaft couplings

    Directory of Open Access Journals (Sweden)

    Jaroslav HOMIŠIN

    2007-01-01

    Full Text Available Main effort of every design engineer is reduction of torsional oscillation in any mechanical system. At present this problem can be solved by means of a suitable modification of dynamic properties of flexible shaft couplings according to dynamics in the given systems. But the dynamic properties of nowadays-applied flexible couplings arenot unchangeable because of aging and fatigue processes occurring in flexible coupling elements. Result of this fact causes detuning of mechanical system. Taking into consideration the above-mentioned situation, we suggest for mechanical systems application of a newly developed pneumatic couplings that have constant characteristicfeatures during the whole current operation and thus they have a positive influence on the system running.

  10. Shaft Diameter Measurement Using Structured Light Vision

    OpenAIRE

    2015-01-01

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is meas...

  11. Equipamento para ensaios estáticos de transmissões a cardan

    Directory of Open Access Journals (Sweden)

    Moreira Cláudio Alves

    2002-01-01

    Full Text Available Os componentes das transmissões a cardan, utilizados intensivamente nas áreas automotiva e agrícola, estão sujeitos a cargas torcionais, axiais e de flexão, as quais podem ser estudadas em banco dinamométrico. Descreve-se neste trabalho o projeto de equipamento para ensaios estáticos, no qual torques relativamente altos, na árvore de saída, necessários nos ensaios em questão, são obtidos por meio de dois redutores de rosca-sem-fim, a partir de torques baixos, impressos na árvore de entrada por uma alavanca de acionamento manual. Uma célula de carga indica a força aplicada a um braço de alavanca, enquanto um goniômetro indica o ângulo de torção correspondente à deformação do espécime testado. O equipamento foi submetido a testes experimentais a fim de ajustar e comprovar sua resistência mecânica e detectar possíveis deformações na sua estrutura, alcançado-se torque máximo de 3.139 N*m (320 kgf*m. Analisaram-se, também, as magnitudes de erros prováveis.

  12. Theoretical Analysis of the Shaft

    Directory of Open Access Journals (Sweden)

    Jajneswar Nanda

    2013-01-01

    Full Text Available This paper represents the dynamic response of a steel shaft which is fixed at both ends by bearing. The shaft is subjected to both axial and bending loads. The behavior of the shaft in the presence of two transverse cracks subjected to the same angular position along longitudinal direction is observed by taking basic parameters such as nondimensional depth (bi/D, nondimensional length (Li/L, and three relative natural frequencies with their relative mode shapes. The compliance matrix is calculated from the stress intensity factor for two degrees of freedom. The dynamic nature of the cracked shaft at two cracked locations at a different depth is observed. The compliance matrix is a function of crack parameters such as depth and location of crack from any one of the bearings. The three relative natural frequencies and their mode shapes at a different location and depth obtained analytical and experimental method. Multiple adaptive neurofuzzy inference system (MANFIS methodology (an inverse technique is used for locating the cracks at any depth and location. The input of the MANFIS is provided with the first three natural frequencies and the first three mode shapes obtained from analytical method. The predicted result of the MANFIS (relative crack location and depth has been validated using the results from the developed experimental setup.

  13. Repairing A Shaft Prone To Fatigue

    Science.gov (United States)

    Sharp, Roger A.; Larsen, David V.; Bates, Garold A.

    1991-01-01

    Shaft of hydraulic motor now outlives its bearings. Procedure for repairing John Deere Series 50 (or equivalent) hydraulic motor solves problem posed by common type of fatigue failure of shaft. Includes forming internally threaded hole in end of shaft, inserting double-threaded end stud, and adding washers and collars.

  14. The influence of Cardan rotation sequence on angular orientation data for the lower limb in the soccer kick.

    Science.gov (United States)

    Lees, Adrian; Barton, Gabor; Robinson, Mark

    2010-02-01

    The influence of the Cardan rotation sequence on the orientation angles for joints is well known but has not been explored for dynamic sports movements. The purpose of this study is to establish the influence of Cardan rotation sequence on the orientation angles of the ankle, knee, and hip of the support leg and pelvis during dynamic sports movements, typified by a maximal instep kick in soccer. We found that: (a) the X (flexion/extension) axis rotations provide data that are robust for any sequence used other than the YXZ sequence, although the Y (abduction/adduction) and Z (internal/external) axes rotations are variable in both shape and offset magnitude; (b) the preferred rotation sequence is either XYZ or XZY for dynamic sports movements, although for the soccer kick the XYZ rotation sequence has been widely used and so this is recommended as a standard; and (c) most uncertainties exist in the Y and Z axes and are most apparent at the beginning of the movement. Where uncertainty exists in identifying Y and Z axes orientations, the integrated angular velocity may be considered as an alternative to determine the relative changes in segment orientation.

  15. Shaft Diameter Measurement Using Structured Light Vision.

    Science.gov (United States)

    Liu, Siyuan; Tan, Qingchang; Zhang, Yachao

    2015-08-12

    A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  16. Shaft Diameter Measurement Using Structured Light Vision

    Directory of Open Access Journals (Sweden)

    Siyuan Liu

    2015-08-01

    Full Text Available A method for measuring shaft diameters is presented using structured light vision measurement. After calibrating a model of the structured light measurement, a virtual plane is established perpendicular to the measured shaft axis and the image of the light stripe on the shaft is projected to the virtual plane. On the virtual plane, the center of the measured shaft is determined by fitting the projected image under the geometrical constraints of the light stripe, and the shaft diameter is measured by the determined center and the projected image. Experiments evaluated the measuring accuracy of the method and the effects of some factors on the measurement are analyzed.

  17. 螺杆钻具中的齿瓣式万向轴%The gear-petal style cardan shaft used in screw drilling tools

    Institute of Scientific and Technical Information of China (English)

    周易文; 刘重康

    2001-01-01

    目前,国内生产使用的万向轴均为花瓣式万向轴,其结构简单、加工速度快,但其寿命极短,成为制约螺杆钻具寿命的关键部件.现文以合理受力为依据,设计了与花瓣式万向轴截然相反的线型,称齿瓣式万向轴,其合理的受力、耐磨性及工艺处理使寿命成倍提高.现场使用表明,齿瓣式万向轴成为螺杆钻具中寿命最长的部件.

  18. Contact analysis for cardan shaft spline of high speed EMUs%高速动车组万向节传动轴花键接触分析

    Institute of Scientific and Technical Information of China (English)

    周春平; 张开林

    2008-01-01

    该高速动车组的双联式虎克万向节传动轴,均匀传递转矩和旋转运动.为适应不同工况,中间轴采用空心花键轴,对其迁行受力分析,得知在运转过程中,花键轴在承受转矩作用的同时还承受弯矩作用.鉴于经兵接触理论的局限性,应用ANSYS Workbench 11.0对中间轴花键进行有限元建横及接触分析,得出该中间轴花键在同时承受转矩和弯矩的情况下花键齿面接触应力的分布情况,对进一步研究齿面磨损及疲劳强度有一定的借鉴意义.

  19. CRH5型动车万向轴扭转振动分析%Analysis on the Torsional Vibration of Cardan Shaft on CRH5 Motor Car

    Institute of Scientific and Technical Information of China (English)

    姚远; 张红军; 罗赟; 李秋泽

    2009-01-01

    采用多刚体动力学软件SIMPACK建立包含传动系统的单节CRH5高速动车模型,对在万向轴波动附加力矩作用下引起的传动系统扭转振动进行分析,并给出万向轴扭转刚度合理的选用范围.研究结果表明:由于万向轴传动不等速性而产生波动附加力矩,导敏传动系统产生强迫振动;附加力矩的波动频率与动车运行速度有关,强迫振动的频率为万向轴输入轴旋转频率的2倍,附加力矩幅值与输入轴角速度的平方成正比;万向轴扭转刚度的选用应以传动系统固有频率避开正常运行时万向轴强迫振动频率为原则.建议选用的万向轴扭转刚度小于560 kN·m·rad-1.

  20. 瓣形万向轴瓣齿的拉伸强度分析%Analysis of tensile strength of flapper teeth of valvular cardan shaft

    Institute of Scientific and Technical Information of China (English)

    李增亮; 苗长山; 孙浩玉; 李继志

    2006-01-01

    提出了瓣形万向轴承受拉伸载荷时瓣齿强度的理论分析方法,利用该方法对万向轴的瓣齿进行了应力分析,根据应力分析的结果讨论了瓣形万向轴的2种主要失效形式,并分析了瓣齿的结构参数对万向轴失效形式的影响.应用ANSYS分析软件对瓣形万向轴承受拉伸载荷时瓣齿的强度进行了有限元分析,从计算结果与实验结果的对比可以看出,两者基本上是一致的,说明利用ANSYS处理瓣形万向轴瓣齿的拉伸强度问题是可行的,计算结果可信,因此有限元计算可以作为今后瓣形万向轴结构设计和强度校核的重要参考依据.

  1. Modal Analysis of Shaft Vibration for Double Cardan Joint System%双万向节系统轴振的模态分析

    Institute of Scientific and Technical Information of China (English)

    刘小勇; 葛文杰; 张永红; 张辉

    2014-01-01

    以某型号飞机飞控系统中的双万向节系统为例,对系统进行轴振分析.通过弹性轴轴振方程的建立,计算得到了系统的固有频率和振型;在Pro/E中建立了双万向节系统的实体模型,然后导入ANSYS Workbench中进行模态分析;将理论计算结果与仿真结果进行对比分析,验证分析的正确性,并分析了影响系统轴振固有频率和振型的因素.

  2. Hermetic seal for a shaft

    Science.gov (United States)

    Lombardi, F. (Inventor)

    1982-01-01

    An hermetic seal for a linear rod having a portion thereof projected axially through a port defined in a wall for a pressure chamber and supported thereby for omni-directional motion is described. The seal is characterized by a resilient, impervious, cylindrical body having a first section concentrically related to the shaft and integrally affixed thereto comprising a linear ordered array of annular flutes. A second section integrally is affixed to the wall of the chamber and concentrically related to the port comprising a second linear ordered array of annular flutes. A third section is interposed between the first and second sections and integrally affixed in coaxial alignment therewith comprising an annular ordered array of linear flutes concentrically related to the shaft, whereby axial, angular, and pivotal motion of the rod is accommodated.

  3. Shaft MisalignmentDetectionusing Stator Current Monitoring

    OpenAIRE

    2013-01-01

    This paper inspects the misaligned of shaft by usingdiagnostic medium such as current and vibration.Misalignments in machines can cause decrease inefficiency and in the long-run it may cause failurebecause of unnecessary vibration, stress on motor,bearings and short-circuiting in stator and rotorwindings.In this study, authors investigate the onsetof instability on a shaft mounted on journal bearings.Shaft displacement and stator current samples duringmachine run up under misaligned condition...

  4. Shaft MisalignmentDetectionusing Stator Current Monitoring

    Directory of Open Access Journals (Sweden)

    Alok Kumar Verma, Somnath Sarangi and M.H. Kolekar

    2013-03-01

    Full Text Available This paper inspects the misaligned of shaft by usingdiagnostic medium such as current and vibration.Misalignments in machines can cause decrease inefficiency and in the long-run it may cause failurebecause of unnecessary vibration, stress on motor,bearings and short-circuiting in stator and rotorwindings.In this study, authors investigate the onsetof instability on a shaft mounted on journal bearings.Shaft displacement and stator current samples duringmachine run up under misaligned condition aremeasured, analyzed and presented here. Verificationof shaft alignment is done by precision laseralignment kit. Result shows that misalignment is theparameter that is more responsible for the cause ofinstability.

  5. The appropriateness of the helical axis technique and six available cardan sequences for the representation of 3-d lead leg kinematics during the fencing lunge.

    Science.gov (United States)

    Sinclair, Jonathan; Taylor, Paul J; Bottoms, Lindsay

    2013-01-01

    Cardan/Euler angles represent the most common technique for the quantification of segmental rotations. Cardan angles are influenced by their ordered sequence, and sensitive to planar-cross talk from the dominant rotation plane, which may affect the angular parameters. The International Society of Biomechanics (ISB) currently recommends a sagittal, coronal, and then transverse (XYZ) ordered sequence, although it has been proposed that when quantifying non-sagittal rotations this may not be the most appropriate technique. This study examined the influence of the helical and six available Cardan sequences on lower extremity three-dimensional (3-D) kinematics of the lead leg during the fencing lunge. Kinematic data were obtained using a 3-D motion capture system as participants completed simulated lunges. Repeated measures ANOVAs were used to compare discrete kinematic parameters, and intraclass correlations were also utilized to determine evidence of planar crosstalk. The results indicate that in all three planes of rotation, peak angle and range of motion angles using the YXZ and ZXY sequences were significantly greater than the other sequences. It was also noted that the utilization of the YXZ and ZXY sequences was associated with the strongest correlations from the sagittal plane, and the XYZ sequence was found habitually to be associated with the lowest correlations. It appears that for accurate representation of 3-D kinematics of the lead leg during the fencing lunge, the XYZ sequence is the most appropriate and as such its continued utilization is encouraged.

  6. Ultrasonic test of highly stressed gear shafts

    Energy Technology Data Exchange (ETDEWEB)

    Schreiner, T. [Siemens AG, Power Generation, KWU, Muelheim (Germany); Heinrich, W. [Siemens AG, Power Generation, KWU, Berlin (Germany); Achtzehn, J. [Siemens AG, Power Generation, ICVW, Erlangen (Germany); Hensley, H. [Siemens Power Generation (Germany)

    1998-12-31

    In the power plant industry, gears are used for increasingly higher turbine capacities. Efficiency enhancements, particularly for the combined gas and steam turbine process, lead to an increase in stresses, even for high-performance gears. Consequently, the requirements for non-destructive material testing are on the increase as well. At Siemens KWU, high-performance gears are used so far only for gas turbines with lower rating (65 MW) to adapt the gas turbine speed (5413 rpm) to the generator speed (3000 rpm/ 50 Hz or 3600 rpm/60 Hz). The gear train consists of a forged and case-hardened wheel shaft and pinion shaft made of material 17 CrNiMo 6, where the wheel shaft can be either a solid or a hollow shaft. Dimensions are typically 2.3 m length and 1 m diameter. As a rule, pinion shafts are solid. The gear design, calling for an additional torsion shaft turning inside the hollow wheel shaft, can absorb more torsional load surges and is more tolerant of deviations during gear train alignment. This design requires two additional forgings (torsion shaft and hub) and an additional bearing 2 refs.

  7. Analysis of Broken Shaft Trouble for SWC44 Cardan Shaft at Section Steel Works and the Proposals%对型钢厂SWC440万向轴断轴事故的分析与建议

    Institute of Scientific and Technical Information of China (English)

    彭金城

    2006-01-01

    针对一起生产企业和设备生产厂家有争议的SWC440万向轴断轴事故进行了检测分析,通过对断轴进行解体、检测、分析认定,由于"卡钢"和"退钢"造成扭矩或转矩过大形成事故.提出了改进建议.

  8. Online shaft encoder geometry compensation for arbitrary shaft speed profiles using Bayesian regression

    Science.gov (United States)

    Diamond, D. H.; Heyns, P. S.; Oberholster, A. J.

    2016-12-01

    The measurement of instantaneous angular speed is being increasingly investigated for its use in a wide range of condition monitoring and prognostic applications. Central to many measurement techniques are incremental shaft encoders recording the arrival times of shaft angular increments. The conventional approach to processing these signals assumes that the angular increments are equidistant. This assumption is generally incorrect when working with toothed wheels and especially zebra tape encoders and has been shown to introduce errors in the estimated shaft speed. There are some proposed methods in the literature that aim to compensate for this geometric irregularity. Some of the methods require the shaft speed to be perfectly constant for calibration, something rarely achieved in practice. Other methods assume the shaft speed to be nearly constant with minor deviations. Therefore existing methods cannot calibrate the entire shaft encoder geometry for arbitrary shaft speeds. The present article presents a method to calculate the shaft encoder geometry for arbitrary shaft speed profiles. The method uses Bayesian linear regression to calculate the encoder increment distances. The method is derived and then tested against simulated and laboratory experiments. The results indicate that the proposed method is capable of accurately determining the shaft encoder geometry for any shaft speed profile.

  9. Shaft Sinking at the Nevada Test Site, U1h Shaft Project

    Energy Technology Data Exchange (ETDEWEB)

    B. Briggs; R. Musick

    2001-03-01

    The U1h Shaft Project is a design/build subcontract to construct one 6.1 meter (m) (20 feet (ft)) finished diameter shaft to a depth of 321.6 m (1,055 ft.) at the Nevada Test Site. Atkinson Construction was subcontracted by Bechtel Nevada to construct the U1h Shaft for the U.S. Department of Energy. The project consists of furnishing and installing the sinking plant, construction of the 321.6 m (1,055 ft.) of concrete lined shaft, development of a shaft station at a depth of 297.5 m (976 ft.), and construction of a loading pocket at the station. The outfitting of the shaft and installation of a new hoist may be incorporated into the project at a later date. This paper will describe the design phase, the excavation and lining operation, shaft station construction and the contractual challenges encountered on this project.

  10. Exhaust powered drive shaft torque enhancer

    Energy Technology Data Exchange (ETDEWEB)

    Koch, A.B.

    1986-09-30

    This patent describes a power producing combination including an internal combustion engine and a mounting frame therefor, and power transmission means including rotating drive shaft means connected to the engine. The improvement described here is a drive shaft torque enhancing device, the device comprising: a multiplicity of blades secured to the drive shaft, equally spaced therearound, each generally lying in a plane containing the axis of the drive shaft; torque enhancer feed duct means for selectively directing a stream of exhaust gases from the engine to impact against the blades to impart torque to the drive shaft; and wherein the power producing combination is used in a vehicle, the vehicle having braking means including a brake pedal; and the power producing combination further comprising torque enhancer disengagement means responsive to motion of the brake pedal.

  11. Passive magnetic bearing for a horizontal shaft

    Energy Technology Data Exchange (ETDEWEB)

    Post, Richard F.

    2003-12-02

    A passive magnetic bearing is composed of a levitation element and a restorative element. The levitation element is composed of a pair of stationary arcuate ferromagnetic segments located within an annular radial-field magnet array. The magnet array is attached to the inner circumference of a hollow shaft end. An attractive force between the arcuate segments and the magnet array acts vertically to levitate the shaft, and also in a horizontal transverse direction to center the shaft. The restorative element is comprised of an annular Halbach array of magnets and a stationary annular circuit array located within the Halbach array. The Halbach array is attached to the inner circumference of the hollow shaft end. A repulsive force between the Halbach array and the circuit array increases inversely to the radial space between them, and thus acts to restore the shaft to its equilibrium axis of rotation when it is displaced therefrom.

  12. Mathematical Modelling of the Heald Shaft

    Directory of Open Access Journals (Sweden)

    Bílek Martin

    2016-12-01

    Full Text Available The manufacturers of weaving equipment recently endeavour to minimise the necessary designing plays in the weaving loom mechanisms. One of the mechanisms most exposed to stress is the shedding motion that defines the held-shaft stroke. Its end part is the heald shaft. The heald shaft constitutes a problematic assembly of the shedding motion. The design employed presently is characterised by dynamic impact loading caused by designing play in the suspension of healds into the heald shaft. During weaving cycle, the healds fly between the main beams of the heald shaft, producing a considerable force pulse. This paper is concerned with the description of dynamic behaviour of the existing design on the basis of mathematical modelling and verification of obtained results by means of experimental analysis.

  13. Shaft/shaft-seal interface characteristics of a multiple disk centrifugal blood pump.

    Science.gov (United States)

    Manning, K B; Miller, G E

    1999-06-01

    A multiple disk centrifugal pump (MDCP) is under investigation as a potential left ventricular assist device. As is the case with most shaft driven pumps, leakage problems around the shaft/shaft seal interface are of major interest. If leakage were to occur during or after implantation, potential events such as blood loss, clotting, blood damage, and/or infections might result in adverse effects for the patient. Because these effects could be quite disastrous, potential shaft and shaft seal materials have been investigated to determine the most appropriate course to limit these effects. Teflon and nylon shaft seals were analyzed as potential candidates along with a stainless steel shaft and a Melonite coated shaft. The materials and shafts were evaluated under various time durations (15, 30, 45, and 60 min), motor speeds (800, 1,000, 1,200, and 1,400 rpm), and outer diameters (1/2 and 3/4 inches). The motor speed and geometrical configurations were typical for the MDCP under normal physiologic conditions. An air and water study was conducted to analyze the inner diameter wear, the inner temperature values, and the outer temperature values. Statistical comparisons were computed for the shaft seal materials, the shafts, and the outer diameters along with the inner and outer temperatures. The conclusions made from the results indicate that both the tested shaft seal materials and shaft materials are not ideal candidates to be used for the MDCP. Teflon experienced a significant amount of wear in air and water studies. Nylon did experience little wear, but heat generation was an evident problem. A water study on nylon was not conducted because of its molecular structure.

  14. 30 CFR 57.19109 - Shaft inspection and repair.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shaft inspection and repair. 57.19109 Section 57.19109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Shafts § 57.19109 Shaft inspection and repair. Shaft inspection and repair work in vertical...

  15. 30 CFR 56.19109 - Shaft inspection and repair.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Shaft inspection and repair. 56.19109 Section 56.19109 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND... Hoisting Shafts § 56.19109 Shaft inspection and repair. Shaft inspection and repair work in vertical...

  16. Reliability assessment of underground shaft closure

    Energy Technology Data Exchange (ETDEWEB)

    Fossum, A.F. [RE/SPEC, Inc., Rapid City, SD (United States); Munson, D.E. [Sandia National Labs., Albuquerque, NM (United States)

    1994-12-31

    The intent of the WIPP, being constructed in the bedded geologic salt deposits of Southeastern New Mexico, is to provide the technological basis for the safe disposal of radioactive Transuranic (TRU) wastes generated by the defense programs of the United States. In determining this technological basis, advanced reliability and structural analysis techniques are used to determine the probability of time-to-closure of a hypothetical underground shaft located in an argillaceous salt formation and filled with compacted crushed salt. Before being filled with crushed salt for sealing, the shaft provides access to an underground facility. Reliable closure of the shaft depends upon the sealing of the shaft through creep closure and recompaction of crushed backfill. Appropriate methods are demonstrated to calculate cumulative distribution functions of the closure based on laboratory determined random variable uncertainty in salt creep properties.

  17. Waste and dust utilisation in shaft furnaces

    OpenAIRE

    Senk, D.; Babich, A.; Gudenau, H. W.

    2005-01-01

    Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilized e.g. in agglomeration processes (sintering, pelletizing or briquetting) and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverized coal (PC) has been studied when injecting into shaft furnaces. Following sha...

  18. CENTRIFUGAL PUMP AND SHAFT SEALING MEANS

    Science.gov (United States)

    Rushing, F.C.

    1960-09-01

    A description is given of sealing means between a hollow rotatable shaft and a stationary member surrounding the shaft which defines therewith a sealing space of annular cross-section, comprising a plurality of axially spaced rings held against seats by ring springs which serve to subdivide the sealing space- into a plurality of zones. Process gas introduced into the hollow shaft through a port communicating with a centrally located zone which iu turn communicates with a bore in the sleeve, is removed from the shaft through a second port communicating with an adjacent central zone and discharged through a second bore. A sealant gas is supplied to an end zone under a pressure sufficient to cause it to flow axially into adjacent zones and then maintained at a lower pressure than either the sealant gas source or the process gas inlet zone, preventing the sealant gas from entering the shaft and allowing gases leaking into the sealant gas to be withdrawn and led to a separator.

  19. Instability of asymmetric continuous shaft system

    Science.gov (United States)

    Srinath, R.; Sarkar, Abhijit; Sekhar, A. S.

    2016-11-01

    In this work, the governing equation of asymmetric continuous shaft in inertial frame of reference is studied. In particular, determination of the parameter ranges for the stability or instability of the shaft response is the focus of the present work. The governing equations are a fourth-order coupled partial differential equations containing time dependent coefficients. The equations are non-dimensionalized in terms of two parameters related to the average moment of inertia and the difference of moments of inertia about the principal axes. Using the latter as the asymptotic parameter and employing modal superposition, a formal methodology based on perturbation methods is developed to ascertain the stability and instability characteristics. The methodology is applicable to shafts subjected to some of the classical boundary conditions viz. simply supported, cantilever, and fixed-fixed. Similar stability curves are obtained for each mode for these different boundary conditions. The novel non-dimensionalization scheme chosen leads to the stability boundaries as well as the loci of varying speeds to be in the form of straight lines. The intersection of these lines determine the stable and unstable speed ranges of different asymmetric shafts. The results are generalized for different material and geometric properties of the shaft.

  20. Waste and dust utilisation in shaft furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Senk, D.; Babich, A.; Gudenau, H.W. [Rhein Westfal TH Aachen, Aachen (Germany)

    2005-07-01

    Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilised e.g. in agglomeration processes (sintering, pelletising or briquetting) and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverised coal (PC) has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.

  1. Hair shaft abnormalities--clues to diagnosis and treatment.

    Science.gov (United States)

    Itin, Peter H; Fistarol, Susanna K

    2005-01-01

    Hair dysplasias are congenital or acquired alterations which often involve the hair shaft. Hair shaft abnormalities are characterized by changes in color, density, length and structure. Hair shaft alterations often result from structural changes within the hair fibers and cuticles which may lead to brittle and uncombable hair. The hair of patients with hair shaft diseases feels dry and looks lusterless. Hair shaft diseases may occur as localized or generalized disorders. Genetic predisposition or exogenous factors produce and maintain hair shaft abnormalities. Hair shaft diseases are separated into those with and those without increased hair fragility. In general, optic microscopy and polarized light microscopy of hair shafts provide important clues to the diagnosis of isolated hair shaft abnormalities or complex syndromes. To establish an exact diagnosis of dysplastic hair shafts, a structured history and physical examination of the whole patient are needed which emphasizes other skin appendages such as the nails, sweat and sebaceous glands. Profound knowledge on hair biology and embryology is necessary to understand the different symptom complexes. Therapy of hair shaft disorders should focus on the cause. In addition, minimizing traumatic influences to hair shafts, such as drying hair with an electric dryer or permanent waves and dyes, is important. A short hairstyle is more suitable for patients with hair shaft disorders.

  2. Interference Assembly and Fretting Wear Analysis of Hollow Shaft

    OpenAIRE

    Chuanjun Han; Jie Zhang

    2014-01-01

    Fretting damage phenomenon often appears in the interference fit assembly. The finite element model of hollow shaft and shaft sleeve was established, and the equivalent stress and contact stress were computed after interference assembly. The assembly body of hollow shaft and shaft sleeve was in whirling bending load, and the contact status (sticking, sliding, and opening) and the distribution of stress along one typical contact line were computed under different loads, interferences, hollow d...

  3. FORMATION OF SHAFT SPLINES USING ROLLING METHOD

    Directory of Open Access Journals (Sweden)

    M. Sidorenko

    2012-01-01

    Full Text Available The paper describes design of rolling heads used for cold rolling of straight-sided splines on shafts and presents theoretical principles of this process. These principles make it possible to calculate an effort which is required for pushing billet through rolling-on rolls with due account of metal hardening during deformation.

  4. Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs

    Science.gov (United States)

    Keba, John E.

    1999-01-01

    This paper presents viewgraphs of The Influence of Rocket Engine Characteristics on Shaft Sealing Technology Needs. The topics include: 1) Rocket Turbomachinery Shaft Seals (Inter-Propellant-Seal (IPS) Systems, Lift-off Seal Systems, and Technology Development Needs); 2) Rocket Engine Characteristics (Engine cycles, propellants, missions, etc., Influence on shaft sealing requirements); and 3) Conclusions.

  5. Performance of meta power rotor shaft torque meter

    DEFF Research Database (Denmark)

    Schmidt Paulsen, U.

    2002-01-01

    The present report describes the novel experimental facility in detecting shaft torque in the transmission system (main rotor shaft, exit stage of gearbox) of a wind turbine, the results and the perspectives in using this concept. The measurements arecompared with measurements, based on existing ...... strain gauges and transducers mounted on the main rotor shaft and controller....

  6. Sectional timbering for ascending bed shafts

    Energy Technology Data Exchange (ETDEWEB)

    Murzin, G.S.; Boldin, V.M.; D' yakov, B.V.; Dzyubenko, V.P.; Fayner, I.A.; Posokhov, G.Ye.; Smolin, M.M.

    1979-02-08

    The purpose of the invention is to improve reliability of timbering when coal or rock are lowered through the shaft. The purpose is achieved because each block is equipped with depressions on the radial edges, while a flexible linkage, for example, cable, is attached to the end of the block and is equipped on the end with a transverse rod which enters the depressions of the radial edges of the blocks.

  7. Vibration reduction on automotive shafts using piezoceramics

    Science.gov (United States)

    Kunze, Holger; Riedel, Mathias; Schmidt, Knut; Bianchini, Emanuele

    2003-08-01

    This paper reports an experimental study on active vibration reduction for automotive shafts with the use of piezoelectric material. The work focuses on an axle of an Audi A2. The demand in the automobile sector for higher comfort in the vehicle is of a great importance alongside the requirements of lighter weight and low fuel consumption. These requirements are typically in conflict with each other. One solution is the use of intelligent materials instead of viscoelastic materials and proof mass absorbers. These solutions are quite heavy especially at low frequencies. Active vibration control and piezoelectric devices are advantageous in this application due to their low mass to performance ratio. Our research study explores the use of such piezoelectric devices for an axle. In conjunction with electronics it will reduce vibrations in the first natural bending mode of the axle. Laboratory tests simulated the condition present in the road. At first a stationary set up was used, then a simulated disturbance was input at the attachment points of the shaft. Finally, a test with rotating shaft was performed. Piezoelectric devices (custom QuickPacks from ACX, a Division of Cymer) were used as sensors and as actuators to properly control the axle during the different operating conditions. The power consumption of each actuator pair was less than 20W. The work described here details the test setup, the control strategy, the hardware implementation as well as the test results obtained.

  8. The detection of abandoned mine shafts in the Netherlands

    Energy Technology Data Exchange (ETDEWEB)

    Mooijman, O.P.M.; Vanderkruk, J.; Roest, J.P.A. [Delft University of Technology, Delft (Netherlands). Faculty of Applied Earth Sciences

    1998-09-30

    In the Old Coal Mine District of East Limburg, in the south of the Netherlands, a number of abandoned mine shafts exist of which the exact coordinates are uncertain. The area is now densely populated, and the majority of the shafts are located near or underneath roads and/or houses. Some of these shafts urgently need to be secured for reasons related to a recent rise in deep ground water levels. This paper describes preliminary investigations for abandoned mine shafts by means of aerial photographs and georadar. Inspection of various photo series indicates that the chances of finding clues for abandoned mine shafts are reasonable, and that digital techniques facilitate identification and exact determination of shaft coordinates. In a densely populated survey environment, such as the area in which the abandoned shafts are located, georadar is a suitable shallow geophysical method for mine shaft detection. In these circumstances, shielded antennae give a clearer subsurface image than unshielded antennae. Signal penetration in the loess-rich deposits commonly found in the area is limited, but the results of a trial survey over a known abandoned shaft accurately confirm the geometry of a collapse zone surrounding the shaft center.

  9. Unbalance Force Analysis of Primary Pump Shaft in PGSFR

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Sungkyun; Koo, Gyeonghoi [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2014-05-15

    In this paper, rotor-dynamic characteristics for the primary pump shaft were obtained. On the basis of the results, we decided to almost double the shaft diameter. By virtue of this design change, the revised design can be satisfied with the critical speed design criteria as well as can decrease a number of support bearings. In the results of unbalance analysis, it was figured that the maximum bearing deflections and loads are within the design criteria. All rotating shafts, even in the absence of external loads, have always eccentric distance due to the manufacturing deviations, material defects, and installation error. This unbalance mass resulting in the eccentric distance of the rotating structure causes resonance at critical speeds. The resonance is the state at which the harmonic loads are excited at their natural frequencies causing shafts to vibrate excessively. This vibration of large amplitude causes shafts to bend and twists significantly and leads to permanent failure. Hence, the determination of these rotor-dynamic characteristics of rotating shaft in the mechanical design stage is much important. In this paper following issues are addressed: - Describe how to calculate the unbalance force. - Predict the natural frequency variations and identify critical speeds within or near the operating speed range of a shaft for consideration of the unbalance bearing stiffness and damping. - Determine the available support positions of a pump shaft to avoid resonance within operating speed. - Perform an unbalance response analysis of a shaft in order to calculate shaft displacement and quantify the forces acting on the shaft support that are caused due to shaft unbalance.

  10. Gearbox Reliability Collaborative High-Speed Shaft Calibration

    Energy Technology Data Exchange (ETDEWEB)

    Keller, J.; McNiff, B.

    2014-09-01

    Instrumentation has been added to the high-speed shaft, pinion, and tapered roller bearing pair of the Gearbox Reliability Collaborative gearbox to measure loads and temperatures. The new shaft bending moment and torque instrumentation was calibrated and the purpose of this document is to describe this calibration process and results, such that the raw shaft bending and torque signals can be converted to the proper engineering units and coordinate system reference for comparison to design loads and simulation model predictions.

  11. Strength Check Analysis for Gear Shaft of Automobile Transmission

    OpenAIRE

    Yongxiang Li; Weiqiang Xia; Liwen Nan; Youjia Zhao; Fujin Yu

    2013-01-01

    As the main drive components of the automobile transmission, the performance of gear shaft plays an important role on transmission performance. Aiming at the existing problems of the traditional strength check method of gear shaft, the objective of this study is to take a five-speed transmission as an example, to accomplish the strength analysis of gear shaft of the automobile transmission based on the MASTA software. Furthermore, the simulation modeling of the transmission is built completel...

  12. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    OpenAIRE

    2015-01-01

    This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendic...

  13. Strength Check Analysis for Gear Shaft of Automobile Transmission

    Directory of Open Access Journals (Sweden)

    Yongxiang Li

    2013-09-01

    Full Text Available As the main drive components of the automobile transmission, the performance of gear shaft plays an important role on transmission performance. Aiming at the existing problems of the traditional strength check method of gear shaft, the objective of this study is to take a five-speed transmission as an example, to accomplish the strength analysis of gear shaft of the automobile transmission based on the MASTA software. Furthermore, the simulation modeling of the transmission is built completely to simulate the actual load conditions and complete the process of analysis for the gear shaft. Analytical results show that all gear shafts can fully meet the strength requirements, in addition to the input shaft which has any further improvements. Hence, it is indicated that a new design concept is put forward, that is, using specialized software MASTA for transmission modeling and simulation analysis can heavily improve the design level of the gear shaft, provide the theoretic basis to analyze the dynamic characteristics of gear shaft as well. Finally, it can provide references for the development and application of gear shaft of the automobile transmission.

  14. Ipsilateral Acetabular and Femoral Neck and Shaft Fractures

    Directory of Open Access Journals (Sweden)

    Hideto Irifune

    2015-01-01

    Full Text Available Floating hip injuries and ipsilateral femoral neck and shaft fractures are rare. Additionally, the simultaneous occurrence of these injuries is extremely rare, and only one case report of the simultaneous occurrence of these injuries has been published. Here, we report the case of a patient with ipsilateral acetabular and femoral neck and shaft fractures following a suicide attempt. The patient experienced nonunion of the femoral neck and shaft after the initial operation and therefore underwent reconstruction using a femoral head prosthesis with a long stem and interlocking screws. Our procedure may be used in primary and/or secondary reconstruction for ipsilateral acetabular and femoral neck and shaft fractures.

  15. Humeral shaft fracture with ipsilateral shoulder dislocation

    Institute of Scientific and Technical Information of China (English)

    Prateek Behera; Vishal Kumar; Sameer Aggarwal

    2014-01-01

    Although fracture of the humeral shaft or dislocation of the shoulder joint is a common injury,a simutaneous injury is rare.We present such a case combined with head injury which took precedence over the skeletal injuries.The postoperative rehabilitation was slowed down by the head injury.This case report makes us aware of some problems when managing the patient with this rare injury and helps us understand the management options better.Also the need for proper follow-up and rehabilitation is emphasized.

  16. Shaft Center Orbit in Dynamically Loaded Bearings

    DEFF Research Database (Denmark)

    Klit, Peder

    The aim of this work is to demonstrate how to utilize the bearings damping coefficients to estimate the orbit for a dynamically loaded journal bearing. The classical method for this analysis was developed by Booker in 1965 and described further in 1972. Several authors have refined this method over...... Jorgen W. Lund pointed out in lecture notes that the dynamic damping coefficients of the bearing could be used to find the shaft orbit for dynamically loaded bearings. For simplicity the "Short-Width-Journal-Bearing Theory" is used as a basis for finding the damping coefficients in this work...

  17. Humeral shaft fracture with ipsilateral shoulder dislocation

    Directory of Open Access Journals (Sweden)

    Behera Prateek

    2014-02-01

    Full Text Available 【Abstract】Although fracture of the humeral shaft or dislocation of the shoulder joint is a common injury, a simutaneous injury is rare. We present such a case combined with head injury which took precedence over the skeletal injuries. The postoperative rehabilitation was slowed down by the head injury. This case report makes us aware of some problems when managing the patient with this rare injury and helps us understand the management options better. Also the need for proper follow-up and rehabilitation is emphasized.

  18. 14 CFR 29.931 - Shafting critical speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Shafting critical speed. 29.931 Section 29... speed. (a) The critical speeds of any shafting must be determined by demonstration except that...) If any critical speed lies within, or close to, the operating ranges for idling, power-on,...

  19. 14 CFR 27.931 - Shafting critical speed.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 1 2010-01-01 2010-01-01 false Shafting critical speed. 27.931 Section 27... speed. (a) The critical speeds of any shafting must be determined by demonstration except that...) If any critical speed lies within, or close to, the operating ranges for idling, power on,...

  20. EVALUATION OF NECK SHAFT ANGLE OF FEMUR ON DRY BONES

    OpenAIRE

    Radha; Ravi Shankar; Naveen; Roopa

    2015-01-01

    BACKGROUND: Evaluation of the neck shaft angle of femur helps to understand clinical relevance in bio mechanics of the hip joint. It helps for the better treatment of different pathological conditions of hip and femur and also to design prosthesis. Femoral neck shaft angle is important to convey the information regarding the race to ...

  1. 30 CFR 77.1911 - Ventilation of slopes and shafts.

    Science.gov (United States)

    2010-07-01

    ... connected to the slope or shaft opening with fireproof air ducts; (3) Designed to permit the reversal of the... from the shaft; and (6) Equipped with air ducts which are fire resistant and maintained so as to... exhausting or blowing methods and when metal air ducts are used, they shall be grounded effectively to...

  2. Ipsilateral femoral neck and shaft fractures: An overlooked association

    Energy Technology Data Exchange (ETDEWEB)

    Daffner, R.H. (Dept. of Diagnostic Radiology, Allegheny General Hospital, Pittsburgh, PA (USA) Medical Coll. of Pennsylvania, Pittsburgh, PA (USA)); Riemer, B.L.; Butterfield, S.L. (Dept. of Orthopedic Surgery, Allegheny General Hospital, Pittsburgh, PA (USA) Medical Coll. of Pennsylvania, Pittsburgh, PA (USA))

    1991-05-01

    A total of 304 patients with injuries to the femoral shaft and ipsilateral hip presented between 1984 and 1990. Some 253 of them suffered fractures of the femoral shaft and dislocated hips or fractures of the acetabulum, and 51 of these sustained fractures of the femoral shaft and neck or trochanteric region. All of the trochanteric injuries were demonstrated on the initial radiographs. However, in 11 of the patients with combined femoral shaft and neck fractures, the diagnosis was delayed by as much as 4 weeks. This delay related to the fact that these fractures tended not to separate in the initial evaluation period and that there was external rotation of the proximal femoral fragment due to the femoral shaft fracture. (orig./GDG).

  3. Waste and dust utilisation in shaft furnaces

    Directory of Open Access Journals (Sweden)

    Senk, D.

    2005-12-01

    Full Text Available Wastes and dusts from steel industry, non-ferrous metallurgy and other branches can be utilized e.g. in agglomeration processes (sintering, pelletizing or briquetting and by injection into shaft furnaces. This paper deals with the second way. Combustion and reduction behaviour of iron- and carbon-rich metallurgical dusts and sludges containing lead, zinc and alkali as well as other wastes with and without pulverized coal (PC has been studied when injecting into shaft furnaces. Following shaft furnaces have been examined: blast furnace, cupola furnace, OxiCup furnace and imperial-smelting furnace. Investigations have been done at laboratory and industrial scale. Some dusts and wastes under certain conditions can be not only reused but can also improve combustion efficiency at the tuyeres as well as furnace performance and productivity.

    Los residuos y polvos de filtro provenientes de la industria siderúrgica, de la obtención de metales no ferrosos y de otras industrias, pueden ser utilizados, por ejemplo, en procesos de aglomeración como sintetizado, peletizado o briqueteado. En su caso, estos pueden ser inyectados en los hornos de cuba. Este artículo se enfoca a la inyección de estos materiales en los hornos de cuba. El comportamiento de la combustión y reducción de los polvos ricos en hierro y carbono y también lodos que contienen plomo, zinc y compuestos alcalinos y otros residuos con o sin carbón pulverizado (CP fue examinado, cuando se inyectaron en hornos de cuba. Los siguientes hornos de cuba fueron examinados: Horno alto, cubilote, OxiCup y horno de cuba Imperial Smelting. Las investigaciones se llevaron a cabo a escala de laboratorio e industrial. Algunos residuos y polvos bajo ciertas condiciones, no sólo pueden ser reciclados, sino también mejoran la eficiencia de combustión en las toberas, la operación y productividad del horno.

  4. 全回转推进轴系扭振计算方法研究%Studies on calculation method of torsion vibration for a double cardan joint marine propulsion shafting

    Institute of Scientific and Technical Information of China (English)

    王磊; 周瑞平; 徐翔; 王艳国

    2010-01-01

    分析了全回转推进轴系的特点,建立了全回转推进轴系的扭转振动计算当量模型,提出了扭转振动计算中考虑系统功率分配以及万向联轴器的二次激励的计算方法.以某78m海洋平台供应船全回转推进轴系为例,进行了系统自由振动及强迫振动计算,并与实船扭振测试进行对比,结果表明,考虑系统功率分配及万向联轴器二次激励后的计算更接近于实际,验证了所提出全回转推进轴系扭振计算方法的正确性.

  5. Cardan shaft with function of energy saving in coasting%与万向传动轴制成一体的滑行节能装置及控制

    Institute of Scientific and Technical Information of China (English)

    邵承会; 唐可洪; 张起勋; 王主玉

    2004-01-01

    以双向超越离合器为主体的滑行节能器与汽车万向传动轴制成一体,该结构安装极其方便,能够有效地利用滑行节能.在控制方面,利用光电编码器测量主、从动轴转速,在主动轴和从动轴基本同步时结合,所以结合时无冲击.对改进后的万向轴整体进行的动平衡试验表明,其节油率和使用寿命均有显著地提高,滑行和倒车完全自动实现,无需人为干预.大量的各种路面上的试验运行表明使用可靠,可以转化为实用型产品.

  6. Development of suspended gearboxes for high speed cardan-shaft power bogies%高速万向轴式动力转向架体悬齿轮箱的研究

    Institute of Scientific and Technical Information of China (English)

    陈智芳; 姚建伟

    2002-01-01

    介绍了自主开发研制的试验型动力转向架体悬齿轮箱的结构特点和设计过程,并对箱体进行了有限元强度计算和静强度试验测试,提出了使设计进一步完善的有关建议。

  7. Discussion on Online Monitoring of EMU Gearbox and Cardan Shaft by Applied Optical Fiber Sensors%应用光纤传感器在线监测动车组齿轮箱和万向轴的探讨

    Institute of Scientific and Technical Information of China (English)

    魏永久; 刘盛春

    2013-01-01

    针对动车组齿轮箱和万向轴在线健康监测,提出了一种利用光纤传感器进行健康数据提取的技术方案,并在试验室内进行了模拟试验,最后讨论了该方案实时监测动车组万向轴运行情况的可行性.

  8. 滚珠万向轴在精品螺纹钢轧制中的应用%APPLICATION OF BALL CARDAN SHAFT IN ROLLING OF FINE DEFORMED STEEL BAR

    Institute of Scientific and Technical Information of China (English)

    李惠斌; 尚玉成; 吴际彬; 只金柱; 段雪飞; 李俊

    2011-01-01

    分析了滚珠联轴器和长伸缩大折角滚珠万向轴相对于鼓形齿式联轴器和GSL伸缩型鼓形齿接轴的技术优势,以及新型径向圆周微调大折角长伸缩滚珠万向轴的技术特点.应用后,成功解决了精品螺纹钢轧制的技术难题,填补了万向轴在该领域的国内技术空白.

  9. Detection of the Dynamic Unbalance with Cardan Shaft Applying the Second Wavelet Transform and Singular Value Decomposition%万向轴动不平衡检测的二代小波变换奇异值方法

    Institute of Scientific and Technical Information of China (English)

    丁建明; 林建辉; 王晗; 林森

    2014-01-01

    针对第二代小波变换依然存在频率混叠的更本缺陷,提出一种高速列车万向轴动不平衡车载检测的新方法.该方法的核心是对万向节安装机座的振动加速度信号进行第二代小波变换得到不同尺度的分解信号,应用单尺度信号构造Hankel矩阵,对该矩阵进行奇异值正交化分解,以奇异值关键叠层作为奇异值的选择准则对信号进行重构,应用重构信号的傅里叶谱来检测高速列车万向轴的动不平衡,消除第二代小波变换频率混叠对故障淹没缺陷,凸显故障特征.应用万向轴动不平衡试验数据对该方法进行试验验证,结果表明,该方法能够有效检测万向轴动不平衡引起的基频、倍频和分频的故障特征,与传统小波、纯第二代小波变换相比,该方法在谱的清晰度和故障表征力上得到了显著提高.

  10. CRH250动车组万向联轴器检修工艺的分析%Analysis of the Testing and Maintenance Process of CRH250 Cardan Shaft

    Institute of Scientific and Technical Information of China (English)

    徐汇音

    2013-01-01

    CRH250动车组的万向联轴器在动车运行中,既要传递牵引力矩又要适应各种复杂的运动关系,以保证轮对的自由运动.通过对动车组万向联轴器的结构原理阐述,提出了列车运行里程数与万向联轴器对应的检测原则,分析了不同运行里程后检测维护的工艺及各零部件处理的对策,以确保列车运行时的安全性及可靠性.

  11. 可控弯接头变异万向轴和轴承的强度模拟分析%Strength Simulation Analysis of the Variation Cardan Shaft and Bearing on Controllable Bent Sub

    Institute of Scientific and Technical Information of China (English)

    张光伟; 李钊; 游莉

    2014-01-01

    为了促进我国旋转导向钻井技术发展,对智能型井下闭环旋转导向工具——可控弯接头的结构和工作原理进行了介绍,并用ANSYS软件对旋转导向钻井工具中的变异万向轴和推力轴承进行了研究,分析了推力轴承、滚子和变异万向轴的相互作用及应力分布情况.分析结果表明,接触配合中危险区域的最大应力为234 MPa,发生在轴承上与滚子接触的球窝边缘部分,与赫兹理论相符;变异万向轴和推力轴承都能较好地满足强度要求.

  12. 东风4D型4033号货运机车万向轴%Reason analysis and handling of successive cracks of cardan shafts for No 4033 DF4D freight locomotives

    Institute of Scientific and Technical Information of China (English)

    郑萌明

    2001-01-01

    针对东风4D型机车万向轴连续断裂故障对机车进行全面分析,找出了故障原因是柴油机各缸喷油及燃烧不均匀引起异常振动.通过更换不良喷油器并对各缸进行调整,解决了万向轴连续断裂问题.

  13. Analysis of the Structure and Critical Rotating Speed of the Cardan Shafts for CRH5 Multiple Units%CRH5型动车组万向轴结构及临界转速分析

    Institute of Scientific and Technical Information of China (English)

    冷扬立; 李秋泽; 李庆国; 邬平波

    2010-01-01

    介绍了CRH5型动车组传动系统组成和万向轴基本结构,对万向轴的临界转速进行了理论计算.通过力锤试验和台架试验,找出了传动系统的共振点和共振频率区域,确定了万向轴在传动系统中的临界转速.

  14. Analysis and Improvement on Rough Mill Cardan Shaft Failure in 1750 Hot Strip Mill%1750热轧机组粗轧万向轴失效分析及改进

    Institute of Scientific and Technical Information of China (English)

    王国义

    2011-01-01

    文章分析了八钢1750热轧机组粗轧万向轴结构特点及传动方式,对易发生失效的部分部件进行了强度校核,同时对部件失效的现象及原因进行了分析,通过有限元分析验证,为防止类似失效现象的发生,有针对性地提出了改进措施及方案.

  15. 汽车传动轴万向节磨损试验机的优化设计%The Design of Testing Machine of Cardan Joint of Automobile Drive Shaft

    Institute of Scientific and Technical Information of China (English)

    张良; 邓舟

    2014-01-01

    根据汽车传动轴的实际工作情况,结合国家汽车行业标准QC/T 523-1999中万向节磨损试验规定的相关试验要求,设计了由计算机控制的长轴类零件旋转汽车传动轴万向节磨损试验机,采用了闭环伺服系统给被测零件施加旋转扭矩载荷和轴向往复滑动载荷,有效保证了试验精度和效率,并且节约了能耗.同时,还介绍了传动轴的试验方法,给出了试验机的相关技术参数,并对试验机的整体结构组成和主要技术内容进行了分析.

  16. DYNAMIC DETECTION OF THE DYNAMIC IMBALANCE WITH CARDAN SHAFT APPLYING WAVELET SCALE ENERGY PRIMARY ELEMENT ANALYSIS%万向传动轴动不平衡动态检测的小波能量主元法

    Institute of Scientific and Technical Information of China (English)

    丁建明; 林建辉; 王晗; 黄晨光

    2014-01-01

    提出一种高速列车万向轴动不平衡车载动态检测的新方法.该方法的核心是:对万向节安装机座的振动信号进行谐波小波包分解,提取前19个小波尺度能量形成特征向量,分别统计动平衡、动不平衡万向轴在不同转速条件下振动信号的特征向量而构成主元分析的训练样本,以累积方差贡献量大于0.8作为主分量个数的确定准则,将特征向量从19维降低到2维,应用第一主元和第二主元联合区分万向轴的动不平衡状态.应用台架试验数据对该方法的有效性进行了测试验证,结果表明:该方法能够有效辨别万向轴的不平衡状态,其准确性高,具有一定的工程适应性.

  17. Contact problems for needle bearing of cardan shaft in high speed EMUs%高速动车组万向轴滚针轴承接触问题研究

    Institute of Scientific and Technical Information of China (English)

    周春平; 常锦昕; 唐斌

    2009-01-01

    鉴于经典Hertz接触理论的局限性,基于有限元方法,应用ANSYS建立十字轴万向节传动轴滚针轴承的非线性接触模型,求解了滚针轴承的接触穿透值及接触应力.结果表明:应用ANSYS计算分析滚针轴承的接触问题是可行的,其结果较符合滚针轴承受力变形后的实际情况.求得的滚针轴承的接触穿透值及接触应力的分布情况为滚针轴承设计及轴承失效形式分析提供了一定的理论依据.

  18. 北京型机车电机万向轴报废的原因及修复%Scrapping reasons and renovation of motor cardan shafts of Type Beijing locomotives

    Institute of Scientific and Technical Information of China (English)

    赵爱民; 白金文; 闫永平

    2001-01-01

    通过分析北京型机车传动箱和起动发电机之间的万向轴的结构及在机车运用中的动作原理,确认造成万向轴报废的主要原因,结合实际调查,阐明修复工艺及修复效果.

  19. Shaft Center Orbit in Dynamically Loaded Bearings

    DEFF Research Database (Denmark)

    Klit, Peder

    2005-01-01

    The aim of this work is to demonstrate how to utilize the bearings damping coe±cients to estimate the orbit for a dynamically loaded journal bearing. The classical method for this analysis was developed by Booker in 1965 [1]and described further in 1972 [2]. Several authors have re¯ned this method...... seventies Jorgen W. Lund pointed out in lecture notes that the dynamic damping coe±cients of the bearing could be used to ¯nd the shaft orbit for dynamically loaded bearings. For simplicity the "Short-Width-Journal-Bearing Theory" is used as a basis for ¯nding the damping coe±cients in this work...

  20. Effect of Relative Marker Movement on the Calculation of the Foot Torsion Axis Using a Combined Cardan Angle and Helical Axis Approach

    Directory of Open Access Journals (Sweden)

    Eveline S. Graf

    2012-01-01

    Full Text Available The two main movements occurring between the forefoot and rearfoot segment of a human foot are flexion at the metatarsophalangeal joints and torsion in the midfoot. The location of the torsion axis within the foot is currently unknown. The purpose of this study was to develop a method based on Cardan angles and the finite helical axis approach to calculate the torsion axis without the effect of flexion. As the finite helical axis method is susceptible to error due to noise with small helical rotations, a minimal amount of rotation was defined in order to accurately determine the torsion axis location. Using simulation, the location of the axis based on data containing noise was compared to the axis location of data without noise with a one-sample t-test and Fisher's combined probability score. When using only data with helical rotation of seven degrees or more, the location of the torsion axis based on the data with noise was within 0.2 mm of the reference location. Therefore, the proposed method allowed an accurate calculation of the foot torsion axis location.

  1. Effect of relative marker movement on the calculation of the foot torsion axis using a combined Cardan angle and helical axis approach.

    Science.gov (United States)

    Graf, Eveline S; Wright, Ian C; Stefanyshyn, Darren J

    2012-01-01

    The two main movements occurring between the forefoot and rearfoot segment of a human foot are flexion at the metatarsophalangeal joints and torsion in the midfoot. The location of the torsion axis within the foot is currently unknown. The purpose of this study was to develop a method based on Cardan angles and the finite helical axis approach to calculate the torsion axis without the effect of flexion. As the finite helical axis method is susceptible to error due to noise with small helical rotations, a minimal amount of rotation was defined in order to accurately determine the torsion axis location. Using simulation, the location of the axis based on data containing noise was compared to the axis location of data without noise with a one-sample t-test and Fisher's combined probability score. When using only data with helical rotation of seven degrees or more, the location of the torsion axis based on the data with noise was within 0.2 mm of the reference location. Therefore, the proposed method allowed an accurate calculation of the foot torsion axis location.

  2. A study on centrifugal charaging pump shaft failure investigation

    Energy Technology Data Exchange (ETDEWEB)

    Jo, S. D.; Kim, B. K. [KEPCO, Woolsan (Korea, Republic of)

    2001-05-01

    Pump shafts in the centrifugal charging safety injection pumps in PWRs have been subject to occasional failures over the past several years. Service experience showed that the pump shaft failures can result in significant emergency repair and maintenance costs to the plant. Metallurgical investigations of the pump shafts fabricated prior to 1977 confirmed that the cracking was initiated at stress concentrations sitcs, such as a locknut thread root or a split ring groove, and progressed by a high cycle fatigue mechanism. Westinghouse implemented a series of improvements and upgrades to increase the safety margins and to mitigate the effect of the off-design operating conditions. These included design enhancements as well as material condition (heat treatment) modifications. The pump shaft upgrading program significantly improved the design life of the shafts but did not fully mitigate the issue. Investigation of recent failures of the upgraded shafts suggested that these failures are initiated by a combination of off-design loading events such as loss of flow or gas binding and a reduction of pump shaft resistance to cracking due to the aqueous environmental conditions.

  3. EVALUATION OF NECK SHAFT ANGLE OF FEMUR ON DRY BONES

    Directory of Open Access Journals (Sweden)

    Radha

    2015-04-01

    Full Text Available BACKGROUND: Evaluation of the neck shaft angle of femur helps to understand clinical relevance in bio mechanics of the hip joint. It helps for the better treatment of different pathological conditions of hip and femur and also to design prosthesis. Femoral neck shaft angle is important to convey the information regarding the race to which they belong. Hence the present study was under taken to determine the neck shaft angle of femur in humans. OBJECTIVE: 1. To correct the different types of deformity and to have a normal good walking Mechanism. 2. To know the recent methodology and attempt to evaluate the range of normal Angles of femora and their sex differences. METHODS: ANTHROPOMETRIC: 100 Adult dry bones were studied and analyzed . The neck shaft angle of femur was measured by tracing outlines of contours of all femora. RESULTS: The neck shaft angle of the femur have revealed that there is no much difference in between males and females. There was slightly higher 0.2° in females. INTERPRETATION & CONCLUSION: There was no significant gender difference in neck shaft angle. The Knowledge of knowing the neck shaft angle helps to understand the Biomechanics of the hip joint and also for better treatment of pathological condition of hip and femur.

  4. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    Directory of Open Access Journals (Sweden)

    Luo Jun

    2015-10-01

    Full Text Available This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendicular to the rotating shaft. The reversal measurement method is applied to decrease the effect of inclinometer drifts caused by temperature, to eliminate inclinometer and rotating shaft mechanical error and inclinometer systematic error to attain high measurement accuracy. The uncertainty estimation shows that the accuracy of rotating shaft tilt angle measurement depends mainly on the inclinometer uncertainty and its uncertainty is almost the same as the inclinometer uncertainty in the simulation. The experimental results indicate that measurement time is 4 seconds; the range of rotating shaft tilt angle is 0.002° and its standard deviation is 0.0006° using NS-5/P2 inclinometer, whose precision and resolution are ±0.01° and 0.0005°, respectively.

  5. DC Control Effort Minimized for Magnetic-Bearing-Supported Shaft

    Science.gov (United States)

    Brown, Gerald V.

    2001-01-01

    A magnetic-bearing-supported shaft may have a number of concentricity and alignment problems. One of these involves the relationship of the position sensors, the centerline of the backup bearings, and the magnetic center of the magnetic bearings. For magnetic bearings with permanent magnet biasing, the average control current for a given control axis that is not bearing the shaft weight will be minimized if the shaft is centered, on average over a revolution, at the magnetic center of the bearings. That position may not yield zero sensor output or center the shaft in the backup bearing clearance. The desired shaft position that gives zero average current can be achieved if a simple additional term is added to the control law. Suppose that the instantaneous control currents from each bearing are available from measurements and can be input into the control computer. If each control current is integrated with a very small rate of accumulation and the result is added to the control output, the shaft will gradually move to a position where the control current averages to zero over many revolutions. This will occur regardless of any offsets of the position sensor inputs. At that position, the average control effort is minimized in comparison to other possible locations of the shaft. Nonlinearities of the magnetic bearing are minimized at that location as well.

  6. Rotating Shaft Tilt Angle Measurement Using an Inclinometer

    Science.gov (United States)

    Luo, Jun; Wang, Zhiqian; Shen, Chengwu; Wen, Zhuoman; Liu, Shaojin; Cai, Sheng; Li, Jianrong

    2015-10-01

    This paper describes a novel measurement method to accurately measure the rotating shaft tilt angle of rotating machine for alignment or compensation using a dual-axis inclinometer. A model of the rotating shaft tilt angle measurement is established using a dual-axis inclinometer based on the designed mechanical structure, and the calculation equation between the rotating shaft tilt angle and the inclinometer axes outputs is derived under the condition that the inclinometer axes are perpendicular to the rotating shaft. The reversal measurement method is applied to decrease the effect of inclinometer drifts caused by temperature, to eliminate inclinometer and rotating shaft mechanical error and inclinometer systematic error to attain high measurement accuracy. The uncertainty estimation shows that the accuracy of rotating shaft tilt angle measurement depends mainly on the inclinometer uncertainty and its uncertainty is almost the same as the inclinometer uncertainty in the simulation. The experimental results indicate that measurement time is 4 seconds; the range of rotating shaft tilt angle is 0.002° and its standard deviation is 0.0006° using NS-5/P2 inclinometer, whose precision and resolution are ±0.01° and 0.0005°, respectively.

  7. Mechanical Deformation of Ship Stern-Shaft Mechanical Face Seals

    Institute of Scientific and Technical Information of China (English)

    朱汉华; 刘正林; 温诗铸; 严新平

    2004-01-01

    In ship propeller shaft systems, the shaft seal is a mechanical face seal, which includes a stationary metal seal ring and a rotating ring.The seal faces are deformed with different loads.The deformation of the seal faces affects the performance of mechanical face seals, which leads to water leakage, so the seal face deformation must be analyzed.A mechanics model with deformation equations was developed to describe ship stern-shaft seals.An example was given to verify the deformation equations.The solution of the deformation equations gives a theoretical basis for the analysis of seal leakage and improvements of seal structures.

  8. Predicting remaining life in upper sugar-mill shafts

    Directory of Open Access Journals (Sweden)

    Sara Rodríguez Pulecio

    2010-04-01

    Full Text Available A fracture mechanics-based method is presented for determining critical crack size and residual life of upper sugar-mill shafts having semi-elliptical and circumferential cracks. Due to the multiaxial stress field, an equivalent strain energy release rate stress intensity solution is used in Paris’ law to predict crack growth. Ultrasonic inspection intervals for the shaft were established. The crack zone evaluated was located in the shoulder of the bearing nearest to the square box coupling where about 25% of service failures in these types of shaft are observed.

  9. An alternative method of osteosynthesis for distal humeral shaft fractures.

    Science.gov (United States)

    Levy, Jonathan C; Kalandiak, Steven P; Hutson, James J; Zych, Gregory

    2005-01-01

    Treatment of extra-articular distal humerus shaft fractures with plating techniques is often difficult, as traditional centrally located posterior plates often encroach on the olecranon fossa, limiting distal osseous fixation. The use of a modified Synthes Lateral Tibial Head Buttress Plate (Synthes, Paoli, PA) allows for a centrally placed posterior plating of the humeral shaft that angles anatomically along the lateral column to treat far distal humeral shaft fractures. Fifteen patients treated in this manner were followed to radiographic and clinical union. There were no cases of instrumentation failure or loss of reduction.

  10. Mechanical coupling for a rotor shaft assembly of dissimilar materials

    Science.gov (United States)

    Shi, Jun; Bombara, David; Green, Kevin E.; Bird, Connic; Holowczak, John

    2009-05-05

    A mechanical coupling for coupling a ceramic disc member to a metallic shaft includes a first wedge clamp and a second wedge clamp. A fastener engages a threaded end of a tie-bolt to sandwich the ceramic disc between the wedge clamps. An axial spring is positioned between the fastener and the second wedge clamp to apply an axial preload along the longitudinal axis. Another coupling utilizes a rotor shaft end of a metallic rotor shaft as one wedge clamp. Still another coupling includes a solid ceramic rotor disc with a multiple of tie-bolts radially displaced from the longitudinal axis to exert the preload on the solid ceramic rotor disc.

  11. Reactor coolant pump shaft seal stability during station blackout

    Energy Technology Data Exchange (ETDEWEB)

    Rhodes, D B; Hill, R C; Wensel, R G

    1987-05-01

    Results are presented from an investigation into the behavior of Reactor Coolant Pump shaft seals during a potential station blackout (loss of all ac power) at a nuclear power plant. The investigation assumes loss of cooling to the seals and focuses on the effect of high temperature on polymer seals located in the shaft seal assemblies, and the identification of parameters having the most influence on overall hydraulic seal performance. Predicted seal failure thresholds are presented for a range of station blackout conditions and shaft seal geometries.

  12. Design of the shaft lining and shaft stations for deep polymetallic ore deposits: Victoria Mine case study

    Directory of Open Access Journals (Sweden)

    Sławomir Fabich

    2015-12-01

    Full Text Available In order to properly design a shaft it is necessary to acquire full information about the rock mass in the exploration area. It is especially crucial in the case of the deposit of an unusual vertical intrusion shape, occurring at a great depth. Such a situation implies that the shaft lining design must take into consideration not only the geomechanical properties of the rock mass but also the virgin stresses (often having significant values. In this paper, the methodology of the shaft lining and shaft station lining design for a deep shaft is presented based on the Victoria Mine located in Canada. Taking into consideration the geological structure as well as the results of the laboratory tests, the properties of the rock mass were derived. Next, the numerical calculation was performed based on the elasto-plastic model of the rock mass. The numerical analysis consisted of simulation of the multistage technology of the shaft excavation and lining execution. This allowed to estimate the forces in rock bolts of the temporary ground support as well as stresses in the final concrete lining of the shaft.

  13. Shaft Crack Identification Based on Vibration and AE Signals

    Directory of Open Access Journals (Sweden)

    Wenxiu Lu

    2011-01-01

    Full Text Available The shaft crack is one of the main serious malfunctions that often occur in rotating machinery. However, it is difficult to locate the crack and determine the depth of the crack. In this paper, the acoustic emission (AE signal and vibration response are used to diagnose the crack. The wavelet transform is applied to AE signal to decompose into a series of time-domain signals, each of which covers a specific octave frequency band. Then an improved union method based on threshold and cross-correlation method is applied to detect the location of the shaft crack. The finite element method is used to build the model of the cracked rotor, and the crack depth is identified by comparing the vibration response of experiment and simulation. The experimental results show that the AE signal is effective and convenient to locate the shaft crack, and the vibration signal is feasible to determine the depth of shaft crack.

  14. Latest state of the art - components for shaft hoisting plants

    Energy Technology Data Exchange (ETDEWEB)

    Denk, D. (Deilmann-Haniel Gmbh, Dortmund (Germany, F.R.))

    1990-01-01

    Presents shaft hoisting equipment produced by Deilmann-Haniel in the FRG. The company has produced and installed 10 winches that comply with the RAG standard for heavy payloads. The RAG standard winch has a maximum payload of 20 t and hoisting speed of 4 m/s. Various winch specifications are provided. The company also produces installations for 5.5 m to 6.5 m diameter blindshafts, different types of cages and shaft guide rails. A new C-section guide rail profile has been developed. Deilmann-Haniel furnished shaft hoisting installations for the Bleida-Est ore mine (Morocco) in 1989. Hoisting depth is 320 m and hoisting capacity 100 t/h. Technical details of the Bleida-Est shaft and winch are given. 6 refs.

  15. The location and treatment of disused mine shafts

    Energy Technology Data Exchange (ETDEWEB)

    Oscroft, G.

    1981-01-01

    Methods of locating disused mine shafts, by both direct and nondirect methods are described. Direct methods involve geophysical surveys, including magnetic, gravity, resistivity, and seismic methods. Methods of treatment involve filling, grouting, use of reinforced concrete, capping or netting.

  16. Mechanism of Reinforcement on Inwall of Coal Mine Shaft Wall

    Directory of Open Access Journals (Sweden)

    Jinlong Liu

    2013-05-01

    Full Text Available Based on the theory of elasticity, the analytic solution of temperature stress on shaft wall of coal mine with reinforcement on inwall is deduced. It is shown that with the increment of reinforcement stress Pa, the radial compressive stress &sigmar become larger, the vertical compressive stress &sigmaz become less, while the circumferential stress &sigma &theta changed from compressive stress to tensile stress. The stability of shaft wall enhanced with vertical stress reduced by reinforcement on inwall of shaft wall. Compressive steel plate could be used to reinforce the inwall, characterized with low-cost, short time and construction easy. While the intelligent equipment should be developed further to provide everlasting and greater reinforcement on in wall of coal mine shaft wall.

  17. Gas Flow Distribution in Pelletizing Shaft Furnace

    Institute of Scientific and Technical Information of China (English)

    CAI Jiu-ju; DONG Hui; WANG Guo-sheng; YANG Jun

    2006-01-01

    Through thermal test, cold state experiment, analysis and simulation of thermal process, the gas flow distribution in pelletizing shaft furnace (PSF) was discussed. The results show that there are five flowing trends; among them, the downward roasting gas and the upward cooling gas are the most unsteady, which influence flow distribution greatly. Among the operating parameters, the ratio of inflow is a key factor affecting the flow distribution. The roasting and cooling gases will entirely flow into the roasting zone and internal vertical air channels (IVAC), respectively, if the ratio of inflow is critical. From such a critical operating condition increasing roasting gas flow or decreasing cooling gas flow, the roasting gas starts flowing downwards so as to enter the inside of IVAC; the greater the ratio of inflow, the larger the downward flowrate. Among constructional parameters, the width of roasting zone b1, width of IVAC b2 and width of cooling zone b3, and the height of roasting zone h1, height of soaking zone h2 and height of cooling zone h3 are the main factors affecting flow distribution. In case the ratio of b2/b1, or h3/h2, or h1/h2 is increased, the upward cooling gas tends to decrease while the downward roasting gas tends to increase with a gradual decrease in the ratio of inflow.

  18. Mechanism of Reinforcement on Inwall of Coal Mine Shaft Wall

    OpenAIRE

    Jinlong Liu; Luwang Chen; Jili Wang

    2013-01-01

    Based on the theory of elasticity, the analytic solution of temperature stress on shaft wall of coal mine with reinforcement on inwall is deduced. It is shown that with the increment of reinforcement stress Pa, the radial compressive stress &sigmar become larger, the vertical compressive stress &sigmaz become less, while the circumferential stress &sigma &theta changed from compressive stress to tensile stress. The stability of shaft wall enhanced with vertical stress reduced by reinforcement...

  19. Case studies and analysis of mine shafts incidents in Europe

    OpenAIRE

    Lecomte, Amélie; Salmon, Romuald; Yang, W.; Marshall, Alec; Purvis, M.; Prusek, S.; Bock, Slawomir; Gajda, L.; Dziura, J.; Munos Niharra, Agustin

    2012-01-01

    International audience; Entry to mine workings is normally gained by means of vertical shafts or horizontal or inclined tunnels called adits. Other mining objects such as fan drifts and wheel pits are often associated with mine shafts. Such mining objects may or may not have been filled, wholly or partially, or otherwise sealed to prevent entry when the mine was abandoned. Nowadays mine entries are usually adequately protected on abandonment to prevent accidental ingress. Many earlier mine en...

  20. Freezing drillings at the shaft deepening at Lyukobanya in 1986

    Energy Technology Data Exchange (ETDEWEB)

    Csiszar, L.

    1988-01-01

    The preliminaries of freezing drilling in Hungary are summarized and the deepening of the Lyukobanya shaft by means of this method is discussed. The drilling equipment and the drilling parameters are listed and the incorporation of freezing tubes is dealt with in detail. The problems and measurement of vertical drilling with this technology are presented on the basis of experiments carried out on the Lyukobanya shaft.

  1. The detection of wind turbine shaft misalignment using temperature monitoring.

    OpenAIRE

    2016-01-01

    Temperature is a parameter increasingly monitored in wind turbine systems. This paper details a potential temperature monitoring technique for use on shaft couplings. Such condition monitoring methods aid fault detection in other areas of wind turbines. However, application to shaft couplings has not previously been widely researched. A novel temperature measurement technique is outlined, using an infra-red thermometer which can be applied to online condition monitoring. The method was va...

  2. Shaft Siting and Configuration for Flexible Operating Mode

    Energy Technology Data Exchange (ETDEWEB)

    Robert Boutin

    2001-08-02

    The purpose of this document as stated in the ''Technical Work Plan for Subsurface Design Section FY 01 Work Activities'' (CRWMS M&O 2001a, pg. 14) is to review and evaluate the most current concepts for shaft siting and configuration. The locations of the shaft sites will be evaluated in reference to the overall subsurface ventilation layout shown in Figure 1. The scope will include discussions on pad size requirements, shaft construction components such as collars, shaft stations, sumps, ground support and linings, head frames, fan ducting and facility equipping. In addition to these, shaft excavation methodologies and integration with the overall subsurface construction schedule will be described. The Technical Work Plan (TWP), (CRWMS M&O 2001a), for this document has been prepared in accordance with AP-2.21Q, ''Quality Determinations and Planning for Scientific, Engineering and Regulatory Compliance Activities''. This document will be prepared in accordance with AP-3.10Q, ''Analysis and Models''. This document contributes to Site Recommendation (SR). The intended use of this document is to provide an analysis for shaft siting and configuration criteria for subsequent construction. This document identifies preliminary design concepts that should not be used for procurement, fabrication, or construction.

  3. Real-time monitoring of wind turbine generator shaft alignment using laser measurement.

    OpenAIRE

    2013-01-01

    Shaft Misalignment is one of the most common sources of trouble of wind turbine drive train when rigid couplings connect the shafts. Ideal alignment of the shaft is difficult to be obtained and the couplings attached to the shaft may present angular or parallel misalignment defined also as lateral and axially misalignment. Despite misalignment is often observed in the practice, there are relatively few studies on wind turbine shaft misalignment in the literature and their results are sometime...

  4. Tibia shaft fractures: costly burden of nonunions

    Directory of Open Access Journals (Sweden)

    Antonova Evgeniya

    2013-01-01

    Full Text Available Abstract Background Tibia shaft fractures (TSF are common for men and women and cause substantial morbidity, healthcare use, and costs. The impact of nonunions on healthcare use and costs is poorly described. Our goal was to investigate patient characteristics and healthcare use and costs associated with TSF in patients with and without nonunion. Methods We retrospectively analyzed medical claims in large U.S. managed care claims databases (Thomson Reuters MarketScan®, 16 million lives. We studied patients ≥ 18 years old with a TSF diagnosis (ICD-9 codes: 823.20, 823.22, 823.30, 823.32 in 2006 with continuous pharmaceutical and medical benefit enrollment 1 year prior and 2 years post-fracture. Nonunion was defined by ICD-9 code 733.82 (after the TSF date. Results Among the 853 patients with TSF, 99 (12% had nonunion. Patients with nonunion had more comorbidities (30 vs. 21, pre-fracture and were more likely to have their TSF open (87% vs. 70% than those without nonunion. Patients with nonunion were more likely to have additional fractures during the 2-year follow-up (of lower limb [88.9% vs. 69.5%, P  Conclusions Nonunions in TSF’s are associated with substantial healthcare resource use, common use of strong opioids, and high per-patient costs. Open fractures are associated with higher likelihood of nonunion than closed ones. Effective screening of nonunion risk may decrease this morbidity and subsequent healthcare resource use and costs.

  5. Failure analysis of axle shaft of a fork lift

    Directory of Open Access Journals (Sweden)

    Souvik Das

    2015-04-01

    Full Text Available An axle shaft of fork lift failed at operation within 296 h of service. The shaft transmits torque from discrepancy to wheel through planetary gear arrangement. A section of fractured axle shaft made of induction-hardened steel was analyzed to determine the root cause of the failure. Optical microscopies as well as field emission gun scanning electron microscopy (FEG-SEM along with energy dispersive spectroscopy (EDS were carried out to characterize the microstructure. Hardness profile throughout the cross-section was evaluated by micro-hardness measurements. Chemical analysis indicated that the shaft was made of 42CrMo4 steel grade as per specification. Microstructural analysis and micro-hardness profile revealed that the shaft was improperly heat treated resulting in a brittle case, where crack was found to initiate from the case in a brittle mode in contrast to ductile mode within the core. This behaviour was related to differences in microstructure, which was observed to be martensitic within the case with a micro-hardness equivalent to 735 HV, and a mixture of non-homogeneous structure of pearlite and ferrite within the core with a hardness of 210 HV. The analysis suggests that the fracture initiated from the martensitic case as brittle mode due to improper heat treatment process (high hardness. Moreover the inclusions along the hot working direction i.e. in the longitudinal axis made the component more susceptible to failure.

  6. Torsional Vibration of a Shafting System under Electrical Disturbances

    Directory of Open Access Journals (Sweden)

    Ling Xiang

    2012-01-01

    Full Text Available Torsional vibration responses of a nonlinear shafting system are studied by a modified Riccati torsional transfer matrix combining with the Newmark-β method. Firstly, the system is modeled as a chain consisting of an elastic spring with concentrated mass points, from which a multi-segment lumped mass model is established. Secondly, accumulated errors are eliminated from the eigenfrequencies and responses of the system's torsional vibration by this newly developed procedure. The incremental transfer matrix method, combining the modified Riccati torsional transfer matrix with Newmark-β method, is further applied to solve the dynamical equations for the torsional vibration of the nonlinear shafting system. Lastly, the shafting system of a turbine-generator is employed as an illustrating example, and simulation analysis has been performed on the transient responses of the shaft's torsional vibrations during typical power network disturbances, such as three-phase short circuit, two-phase short circuit and asynchronous juxtaposition. The results validate the present method and are instructive for the design of a turbo-generator shaft.

  7. Isolation and Quantification of Glycosaminoglycans from Human Hair Shaft

    Science.gov (United States)

    Bonovas, Stefanos; Sitaras, Nikolaos

    2016-01-01

    Background There is evidence that glycosaminoglycans (GAGs) are present in the hair shaft within the follicle but there are no studies regarding GAGs isolation and measurement in the human hair shaft over the scalp surface, it means, in the free hair shaft. Objective The purpose of our research was to isolate and measure the total GAGs from human free hair shaft. Methods Seventy-five healthy individuals participated in the study, 58 adults, men and women over the age of 50 and 17 children (aged 4~9). GAGs in hair samples, received from the parietal and the occipital areas, were isolated with 4 M guanidine HCl and measured by the uronic acid-carbazole reaction assay. Results GAGs concentration was significantly higher in the occipital area than in the parietal area, in all study groups. GAG levels from both areas were significantly higher in children than in adults. GAG levels were not associated with gender, hair color or type. Conclusion We report the presence of GAGs in the human free hair shaft and the correlation of hair GAG levels with the scalp area and participants' age. PMID:27746630

  8. Investigation of water aggressiveness towards concrete shaft lining

    Energy Technology Data Exchange (ETDEWEB)

    Majzner-Rulka, H.; Durczynski, S.

    1989-09-01

    Considers the corrosive action exerted by water on concrete shaft linings. Several kinds of water aggressiveness are distinguished: sulfate, acidic, carbonate, magnesian, leachate and of the ammonium type. Laboratory and in situ investigations into water aggressiveness towards shaft lining are described and results are presented. Related Polish standards are discussed. Presence of a new kind of water was established in which Mg{sup 2+} ion concentration reaches 4,500 mg/dm{sup 3} and SO{sub 4}{sup 2-} ion concentration exceeds 3,000 mg/dm{sup 3}. Damage to concrete shaft lining caused by aggressive water was found in shafts of several mines in the Upper Silesia coal basin. Investigations into the effect of high Mg{sup 2+} and SO{sub 4}{sup 2-} ion concentration in water on concrete shaft lining have been conducted at the Research and Development Department of the Mine Work Enterprise Budokop in Myslowice since 1984. Redrafting of related standards is recommended. 5 refs.

  9. Eddy Current Sensing of Torque in Rotating Shafts

    Science.gov (United States)

    Varonis, Orestes J.; Ida, Nathan

    2013-12-01

    The noncontact torque sensing in machine shafts is addressed based on the stress induced in a press-fitted magnetoelastic sleeve on the shaft and eddy current sensing of the changes of electrical conductivity and magnetic permeability due to the presence of stress. The eddy current probe uses dual drive, dual sensing coils whose purpose is increased sensitivity to torque and decreased sensitivity to variations in distance between probe and shaft (liftoff). A mechanism of keeping the distance constant is also employed. Both the probe and the magnetoelastic sleeve are evaluated for performance using a standard eddy current instrument. An eddy current instrument is also used to drive the coils and analyze the torque data. The method and sensor described are general and adaptable to a variety of applications. The sensor is suitable for static and rotating shafts, is independent of shaft diameter and operational over a large range of torques. The torque sensor uses a differential eddy current measurement resulting in cancellation of common mode effects including temperature and vibrations.

  10. Seagull feather shaft: Correlation between structure and mechanical response.

    Science.gov (United States)

    Wang, Bin; Meyers, Marc André

    2017-01-15

    Flight feathers are unique among a variety of keratinous appendages in that they are lightweight, stiff and strong. They are designed to withstand aerodynamic forces, but their morphology and structure have been oversimplified and thus understudied historically. Here we present an investigation of the shaft from seagull primary feathers, elucidate the hierarchical fibrous and porous structure along the shaft length, and correlate the tensile and nanomechanical properties to the fiber orientation. An analysis of the compressive behavior of the rachis based on a square-section model shows a good fit with experimental results, and demonstrates the synergy between the cortex and medulla. Flexural properties of the shaft along the shaft length, analyzed as a sandwich composite, reveal that although all flexural parameters decrease towards the distal shaft, the specific equivalent flexural modulus and strength increase by factors of 2 and 3, respectively. The failure mode in flexure for all specimens is buckling on the compressive surface, whereas the foamy medulla prevents destructive axial cracking and introduces important toughening mechanisms: crack deflection, fiber bridging, and microcracking.

  11. Experimental study on sliding shaft lining mechanical mechanisms under ground subsidence conditions

    Institute of Scientific and Technical Information of China (English)

    姚直书; 杨俊杰; 孙文若

    2003-01-01

    Aimed at more than 60 shaft linings damaged in Huaibei, Datun, Xuzhou and Yanzhou mine areas, this paper presents a new type of sliding shaft lining with asphalt blocks sliding layer. By model test, it is obtained that the deformation characteristics and the mechanical mechanisms of the sliding shaft lining under the condition of ground subsidence. The research results provide a testing basis for the sliding shaft lining design. By now, this kind of sliding shaft lining had been applied in 9 shafts in China and Bangladesh.

  12. Assessment of shaft safety and management system of controlling engineering information

    Energy Technology Data Exchange (ETDEWEB)

    Liu Rui-xin; Xu Yan-chun [Yanzhou Mining Group Ltd., Zoucheng (China)

    2008-02-15

    Evaluating shaft safety and establishing a system for controlling engineering information is very important because more than 90 shafts in thick alluvial areas suddenly have shaft wall fracturing or breaking problems and there are more than a few hundred shafts of similar geologic conditions. Taking shaft control in the Yangzhou Coal Mining Group as an example, an assessment and management system and related software were established. This system includes basic information of the mine, measurement results and analysis, and functions of empirical and theoretical forecasting and finite element analysis, which are confirmed to be very effective for guiding shaft well control engineering in practice. 8 refs., 3 figs., 2 tabs.

  13. Design of Energy Scavengers Mounted on Rotating Shafts

    CERN Document Server

    Shahruz, S M

    2008-01-01

    In this paper, a novel energy scavenger is proposed. The scavenger consists of a cantilever beam on which piezoelectric films and a mass are mounted. The mass at the tip of the beam is known as the proof mass and the device is called either an energy scavenger or a beam-mass system. The beam-mass system is mounted on a rotating shaft, where the axis of the shaft is horizontal. A single-degree-of-freedom (SDOF) mathematical model is derived for the scavenger and its properties are carefully examined. From the model, it becomes clear that the rotation of the shaft and gravity cause both parametric excitations and exogenous forces which make the beam-mass system vibrate. Guidelines are provided as how to choose the scavenger parameters in order to have it resonate. Examples are given to illustrate the performance of the proposed scavenger.

  14. Bentonite as a waste isolation pilot plant shaft sealing material

    Energy Technology Data Exchange (ETDEWEB)

    Daemen, J.; Ran, Chongwei [Univ. of Nevada, Reno, NV (United States)

    1996-12-01

    Current designs of the shaft sealing system for the Waste Isolation Pilot Plant (WIPP) propose using bentonite as a primary sealing component. The shaft sealing designs anticipate that compacted bentonite sealing components can perform through the 10,000-year regulatory period and beyond. To evaluate the acceptability of bentonite as a sealing material for the WIPP, this report identifies references that deal with the properties and characteristics of bentonite that may affect its behavior in the WIPP environment. This report reviews published studies that discuss using bentonite as sealing material for nuclear waste disposal, environmental restoration, toxic and chemical waste disposal, landfill liners, and applications in the petroleum industry. This report identifies the physical and chemical properties, stability and seal construction technologies of bentonite seals in shafts, especially in a saline brine environment. This report focuses on permeability, swelling pressure, strength, stiffness, longevity, and densification properties of bentonites.

  15. Coupled exofixator for comminuted fracture of humeral shaft

    Institute of Scientific and Technical Information of China (English)

    马红如; 马树林; 尹同珍

    2005-01-01

    Objective: To report and assess the efficacy of a coupled exofixator in the treatment of comminuted fracture of the humeral shaft.Methods: From June 1999 to September 2003, 24 patients with comminuted fracture of the humeral shaft were treated in our department, in whom 11 were involved in left humerus fractures and 13 in right humerus fractures. Closed reduction or open reduction with a small incision as well as a coupled exofixator was used to treat these patients. Results: All cases got anatomical reduction after 6-12 months follow-up. The time for fracture union averaged 5.8 months with a good functional recovery of the shoulder-elbow joints. Conclusions: The coupled exofixator is favorable to the treatment of comminuted humeral shaft fractures. It can shorten union time and avoid nonunion occurrence.

  16. The Laser Shaft Alignment System with Dual PSDs

    Institute of Scientific and Technical Information of China (English)

    JIAO Guohua; LI Yulin; ZHANG Dongbo; LI Tonghai; HU Baowen

    2006-01-01

    Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with the measurement software. The laser alignment system with dual PSDs was improved on a single PSD system, and it gets higher measurement accuracy than the previous design, and it has been succeeded in designing and implement for actual shaft alignment. In the system, the range of offset measurement is ±4 mm, and the resolution is 1.5 μm, and the accuracy is less than 2 μm.

  17. A laser shaft alignment system with dual PSDs

    Institute of Scientific and Technical Information of China (English)

    JIAO Guo-hua; LI Yu-lin; ZHANG Dong-bo; LI Tong-hai; HU Bao-wen

    2006-01-01

    Shaft alignment is an important technique during installation and maintenance of a rotating machine. A high-precision laser alignment system has been designed with dual PSDs (Position Sensing Detector) to change traditional manual way of shaft alignment and to make the measurement easier and more accurate. The system is comprised of two small measuring units (laser transmitter and detector) and a PDA (Personal Digital Assistant) with measurement software. The laser alignment system with dual PSDs was improved on a single PSD system, and yields higher measurement accuracy than the previous design, and has been successful for designing and implements actual shaft alignment. In the system, the range of offset measurement is ±4 mm, and the resolution is 1.5 μm, with accuracy being less than 2 μm.

  18. Vibration Problems of Rotating Machinery due to Coupling Misalignments

    Science.gov (United States)

    1988-05-01

    angular miaalignments are universal joints ( commonly called Hooke’s Joints or Cardan Joints). As can be seen in figure 3-3 (a through c), a universal...or Cardan joint consists of a drive yoke which is rigidly fastened to the drive shaft, a driven yoke which is rigidly fastened to the driven shaft...stltted clsks Grid coupling * FIGURE 7-1 121 (Piotrowski, 1986). The fourth and fifth major categories of couplings are the universal or Cardan joints and

  19. Granuloma annulare localized to the shaft of the penis

    DEFF Research Database (Denmark)

    Trap, R; Wiebe, B

    1993-01-01

    A case of granuloma annulare localized to the shaft of the penis is reported. The differential diagnoses are discussed. Penile granuloma annulare is a rare disorder and it is concluded that biopsies of penile lesions are recommended to verify the correct diagnosis.......A case of granuloma annulare localized to the shaft of the penis is reported. The differential diagnoses are discussed. Penile granuloma annulare is a rare disorder and it is concluded that biopsies of penile lesions are recommended to verify the correct diagnosis....

  20. Reactor coolant pump shaft seal behavior during blackout conditions

    Energy Technology Data Exchange (ETDEWEB)

    Mings, W.J.

    1985-01-01

    The United States Nuclear Regulatory Commission has classified the problem of reactor coolant pump seal failures as an unresolved safety issue. This decision was made in large part due to experimental results obtained from a research program developed to study shaft seal performance during station blackout and reported in this paper. Testing and analysis indicated a potential for pump seal failure under postulated blackout conditions leading to a loss of primary coolant with a concomitant danger of core uncovery. The work to date has not answered all the concerns regarding shaft seal failure but it has helped scope the problem and focus future research needed to completely resolve this issue.

  1. Fuel Cell Shaft Power Pack - Regulering af brændselsceller

    DEFF Research Database (Denmark)

    Andreasen, Søren Juhl

    2009-01-01

    Afsluttende formidling af forskningsresultater i forbindelse med projektet Fuel Cell Shaft Power Pack......Afsluttende formidling af forskningsresultater i forbindelse med projektet Fuel Cell Shaft Power Pack...

  2. Исследование кинематики двухшарнирной карданной передачи с помощью корреляционно-регрессионного анализа

    OpenAIRE

    Гурвич, Ю. А.; Вареник, А. А.; Августинович, А. Г.; Старовойтова, О. Л.

    2011-01-01

    This article contains a description of a new method of unevenness definition in dependence of obliquity angle and its influence on output cinematic characteristics of two-joint cardan shafts. Also conducted a study of cardan shafts using correlation-regression analysis

  3. Factors that affect the fatigue strength of power transmission shafting and their impact on design

    Science.gov (United States)

    Leowenthal, S. H.

    1986-01-01

    A long standing objective in the design of power transmission shafting is to eliminate excess shaft material without compromising operational reliability. A shaft design method is presented which accounts for variable amplitude loading histories and their influence on limited life designs. The effects of combined bending and torsional loading are considered along with a number of application factors known to influence the fatigue strength of shafting materials. Among the factors examined are surface condition, size, stress concentration, residual stress and corrosion fatigue.

  4. EVALUATION OF STRUCTURAL AND VIBRATIONAL CHARACTERISTIC OF COMPOSITE DRIVE SHAFT FOR AUTOMOBILE USING FEM

    OpenAIRE

    2016-01-01

    In vehicle drive shaft is one of the most important component. It transmits torque from the engine to the differential gear of a rear wheel drive vehicle. Generally the drive shaft is made up of steel alloy but the use of conventional steel has disadvantages such as low specific stiffness and strength and high weight. Nowadays this steel drive shaft is replaced by composite material drive shaft. This advanced composite such as graphite, Kevlar, carbon, glass with suitable resin have advantage...

  5. Outcome of humeral shaft fractures treated by functional cast brace

    Directory of Open Access Journals (Sweden)

    Jitendra Nath Pal

    2015-01-01

    Conclusion: Modified functional cast brace is one of the options in treatment for humeral shaft fractures as it can be applied on the 1 st day of the presentation in most of the situations. Simple objective scoring system was useful particularly in uneducated patients.

  6. Residual stress analysis of drive shafts after induction hardening

    Energy Technology Data Exchange (ETDEWEB)

    Lemos, Guilherme Vieira Braga; Rocha, Alexandre da Silva; Nunes, Rafael Menezes, E-mail: lemos_gl@yahoo.com.br [Universidade Federal do Rio Grande do Sul (UFRS), Porto Algre, RS (Brazil); Hirsch, Thomas Karl [Stiftung Institut für Werkstofftechnik (IWT), Bremen (Germany)

    2014-08-15

    Typically, for automotive shafts, shape distortion manifests itself in most cases after the induction hardening by an effect known as bending. The distortion results in a boost of costs, especially due to machining parts in the hardened state to fabricate its final tolerances. In the present study, residual stress measurements were carried out on automotive drive shafts made of DIN 38B3 steel. The samples were selected in consequence of their different distortion properties by an industrial manufacturing line. One tested shaft was straightened, because of the considerable dimensional variation and the other one not. Firstly, the residual stress measurements were carried out by using a portable diffractometer, in order to avoid cutting the shafts and evaluate the original state of the stresses, and afterwards a more detailed analysis was realized by a conventional stationary diffractometer. The obtained results presented an overview of the surface residual stress profiles after induction hardening and displayed the influence of the straightening process on the redistribution of residual stresses. They also indicated that the effects of the straightening in the residual stresses cannot be neglected. (author)

  7. Asymmetry in gait pattern following tibial shaft fractures

    DEFF Research Database (Denmark)

    Larsen, Peter; Læssøe, Uffe; Rasmussen, Sten

    2017-01-01

    INTRODUCTION: Despite the high number of studies evaluating the outcomes following tibial shaft fractures, the literature lacks studies including objective assessment of patients' recovery regarding gait pattern. The purpose of the present study was to evaluate whether gait patterns at 6 and 12 m...

  8. Metatarsal Shaft Fracture with Associated Metatarsophalangeal Joint Dislocation

    Directory of Open Access Journals (Sweden)

    Taranjit Singh Tung

    2016-01-01

    Full Text Available Metatarsophalangeal joint dislocations of lesser toes are often seen in the setting of severe claw toes. Traumatic irreducible dislocations have been reported in rare cases following both low-energy and high-energy injuries to the forefoot. In this case report, I present a previously unreported association of a metatarsal shaft fracture with metatarsophalangeal joint dislocation of a lesser toe.

  9. Interference Assembly and Fretting Wear Analysis of Hollow Shaft

    Directory of Open Access Journals (Sweden)

    Chuanjun Han

    2014-01-01

    Full Text Available Fretting damage phenomenon often appears in the interference fit assembly. The finite element model of hollow shaft and shaft sleeve was established, and the equivalent stress and contact stress were computed after interference assembly. The assembly body of hollow shaft and shaft sleeve was in whirling bending load, and the contact status (sticking, sliding, and opening and the distribution of stress along one typical contact line were computed under different loads, interferences, hollow degrees, friction coefficient, and wear quantity. Judgment formula of contact state was fixed by introducing the corrected coefficient k. The computation results showed that the “edge effect” appears in the contact surface after interference fit. The size of slip zone is unchanged along with the increase of bending load. The greater the interference value, the bigger the wear range. The hollow degree does not influence the size of stick zone but controls the position of the junction point of slip-open. Tangential contact stress increases with the friction coefficient, which has a little effect on normal contact stress. The relationship between open size and wear capacity is approximately linear.

  10. Controlled blasting and its implications for the NNWSI project exploratory shaft

    Energy Technology Data Exchange (ETDEWEB)

    Van Eeckhout, E.M.

    1987-09-01

    This report reviews controlled blasting techniques for shaft sinking. Presplitting and smooth blasting are the techniques of principal interest. Smooth blasting is preferred for the Nevada Nuclear Waste Storage Investigations exploratory shaft. Shaft damage can be monitored visually or by peak velocity measurements and refractive techniques. Damage into the rock should be limited to 3 ft. 40 refs., 22 figs., 7 tabs.

  11. THE MEASUREMENT AND STUDY OF BLASTING VIBRATION AFFECTING IN SITU CAST CONCRETE LINING OF VERTICAL SHAFT

    Institute of Scientific and Technical Information of China (English)

    黄琦; 李玉民

    1997-01-01

    Vertical shaft is main form of drivage in deep mineral depoist. They also serve as the entrance into and the exit from the underground mine. The main problems in shaft and tunnel engineering is to solve the contradiction between drivage and lining. The measurement of blasting vibration affecting concrete lining strength of vertical shaft is carried out in experiment and theory in this paper.

  12. 含运动副间隙的双万向节系统动力学研究%Research of the System of Double Cardan Joint with Joint Clearance

    Institute of Scientific and Technical Information of China (English)

    张辉; 葛文杰; 宁方立; 赵炜

    2012-01-01

    The solid model of the system of double cardan joint is built through Pro/Engineer, then it is imported into ADAMS to take the dynamic simulation analysis. For the model which does not contain joint clearance, the proper restrain is added according to actual condition, for the model which does contain joint clearance, the dynamic simulation is taken after setting proper contact force parameters according to Hertz theory. Comparing the difference of the result between the simulation which contain joint clearance or not and the result between the simulation which contain different joint clearance, the joint clearance influence to the operating performance of the system of double cardan joint is obtained.%在Pro/E中建立双万向节系统的实体模型,然后导入ADAMS中进行动力学仿真.对于不考虑间隙的模型,根据系统的实际情况添加适当的约束;对于含运动副间隙的模型,根据Hertz理论,在contact工具中设置合适的接触力参数.对比含间隙和不合间隙时系统动力学仿真结果的异同,以及不同间隙时仿真结果的异同,由此得出运动副间隙对双万向节系统工作性能的影响情况.

  13. Shaft Voltage and Life of Bearing electric-erosion for the Brushless DC Motor

    Science.gov (United States)

    Maetani, Tatsuo; Isomura, Yoshinori; Komiyama, Hiroshi; Morimoto, Shigeo

    This paper describes the life of noise of bearing electro-erosion in the shaft voltage of brushless DC motors. We confirmed that shaft voltage is suppressed to equal to or less than the dielectric breakdown voltage of bearing lubricant in the insulated rotor proposed for suppression of shaft voltage. However, since bearing electro-erosion appears over time along with the deterioration of noise performance, the threshold of the shaft voltage to secure noise performance over long periods of time is necessary. Therefore, the threshold of the shaft voltage that influences the life of noise was obtained in acceleration tests.

  14. Failure Mode Analysis Of Torsion Shaft In Garrett-5 Engine Using Two Test Pieces

    Directory of Open Access Journals (Sweden)

    Rio Melvin Aro. T

    2014-08-01

    Full Text Available This work deals with “Failure Analysis of Internal splines in Torsion Shaft” of “TPE 331-5-252D - GARRET ENGINE” which is used in Dornier aircraft. Garret Engine is a type of air breathing engine. It comes under the category of Turboprop engines of Gas turbine engine. As separate shafts are used for propeller and turbine, this aids them to rotate at different RPM. A torsion shaft is used to transmit the torque from main shaft to propeller shaft. Torsion shaft is used to give a deflection which is also used to measure the torque of the engine. This torsion shaft is internally connected with the main power transmission shaft and its other end is coupled to a coupler shaft with engagement of its internal splines to the external splines of coupler shaft. Further this coupler connects to the gearing system and transmits power to the propeller shaft. Due to Continues variable load over internal splines, it is subjected to high rate of wear and tear. This problem can be rectified by Failure Mode Analysis Method, in which heat treatment process of torsion shaft is being carried out. Two test pieces are heat treated separately at different temperatures of 5800C and 5400C at variable time durations. Tuffriding which is a Liquid nitriding process is done with this two test pieces and results are analyzed. The hardness of the material is increased to desired values and its life time is also increased which overcomes the problem.

  15. Design of a Composite Drive Shaft and its Coupling for Automotive Application

    Directory of Open Access Journals (Sweden)

    M.R. Khoshravan

    2012-11-01

    Full Text Available This paper presents a design method and a vibration analysis of a carbon/epoxy composite drive shaft. The designof the composite drive shaft is divided into two main sections: First, the design of the composite shaft and second, thedesign of its coupling. Some parameters such as critical speed, static torque, fiber orientation and adhesive jointswere studied. Tsai-Hill failure criterion was implemented to control the rupture resistance of the composite shaft andthen its critical speed analysis and modal analysis were carried out using ANSYS. The behavior of materials isconsidered nonlinear isotropic for adhesive, linear isotropic for metal and orthotropic for composite shaft. The resultsshowed significant points about the appropriate design of composite drive shafts. The substitution of composite driveshaft has resulted in considerable weight reduction about 72% compared to conventional steel shaft. Furthermore,results revealed that the orientation of fibers had great influence on the dynamic characteristics of the compositeshaft.

  16. Two-stitch technique for distal shaft hypospadias repair.

    Science.gov (United States)

    Herman, Oscar; Heller, Lior; Dorenbaum, Arye; Westreich, Melvyn

    2002-02-01

    The authors present a new technique for distal shaft hypospadias repair using a flip flap fashioned with only two stitches. In raising the flap, the tissues lateral and proximal to the flap are undermined but there is no undermining beneath the flap. The flap is sutured up to the glans with two 4-0 Vicryl sutures. No sutures are placed at the lateral edges of the flap to create the "tube" of the neo-urethra, and no postoperative urinary drainage is used. Thirty-three children with distal shaft hypospadias underwent the "two-stitch" flip flap operation. The complications were one fistula and one case of urinary retention. The technique is an easy method for reconstructing distal penile hypospadias with a very low rate of complications and is suitable for an outpatient surgical setting.

  17. Vibration analysis of parallel misaligned shaft with ball bearing system

    Directory of Open Access Journals (Sweden)

    PSS.Srinivasan

    2011-02-01

    Full Text Available Misalignment is the most common cause of machine vibration. In this paper, experimental studies were performed ona rotor dynamic test apparatus to predict the vibration spectrum for shaft misalignment. A self-designed simplified 3–pin typeflexible coupling was used in the experiments. Vibration accelerations were measured using dual channel vibration analyzerfor baseline and the misalignment condition. The experimental and numerical frequency spectra were obtained. The experimentalpredictions are in good agreement with the numerical results. Both the vibration spectra show that misalignment canbe characterized primarily by 2X shaft running speed. However, misalignment is not close enough to one of the systemnatural frequency to excite the system appreciably. Therefore, in some case the misalignment response is hidden and doesnot show up in the vibration spectrum. The misalignment effect can be amplified, and a high acceleration level at 2X shaftsrunning speed is pronounced in the frequency spectrum.

  18. Elementary calculation of clip connections with incomplete sweep of shaft

    Directory of Open Access Journals (Sweden)

    Ivan P. Shatsky

    2015-06-01

    Full Text Available The article describes promising structures of clip (screw and friction connections with incomplete sweep of shaft used in machines and mechanisms for the oil and gas industry. The contact problems of interaction between semi-hubs and shaft for the symmetric and asymmetric connections are formulated. For structures that are asymmetric relatively the joint bolt two types of interaction are investigated: with and without lateral displacement. Based on a priori assumption about the distribution laws of contact pressure accepted in traditional courses of “Machine Details” an engineering method for calculating of clip connections is developed. Herewith different types of details coupling (with a gap, matched, with tension correspond to concentrated, cosine and sustainable (linear distributions of contact stresses. There are determined an analytical dependences of boundary points and breakloose force on spanning angles, bolt tightening force and tribological properties of joined parts of subassembly.

  19. Integrated analysis of rock mass deformation within shaft protective pillar

    Directory of Open Access Journals (Sweden)

    Ewa Warchala

    2016-01-01

    Full Text Available The paper presents an analysis of the rock mass deformation resulting from mining in the vicinity of the shaft protection pillar. A methodology of deformation prediction is based on a deterministic method using Finite Element Method (FEM. The FEM solution is based on the knowledge of the geomechanical properties of the various geological formations, tectonic faults, types of mining systems, and the complexity of the behaviour of the rock mass. The analysis gave the stress and displacement fields in the rock mass. Results of the analysis will allow for design of an optimal mining system. The analysis is illustrated by an example of the shaft R-VIII Rudna Mine KGHM Polish Copper SA.

  20. Interim reclamation report: Basalt Waste Isolation Project exploration shaft site

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.; Hefty, M.G.

    1990-02-01

    In 1968, a program was started to assess the feasibility of storing Hanford Site defense waste in deep caverns constructed in basalt. This program was expanded in 1976 to include investigations of the Hanford Site as a potential location for a mined commercial nuclear waste repository. Extensive studies of the geotechnical aspects of the site were undertaken, including preparations for drilling a large diameter Exploratory Shaft. This report describes the development of the reclamation program for the Exploratory Shaft Facility, its implementation, and preliminary estimates of its success. The goal of the reclamation program is to return sites disturbed by the repository program as nearly as practicable to their original conditions using native plant species. 43 refs., 19 figs., 9 tabs.

  1. CURRENT TECHNOLOGY AND INNOVATIONS IN FREEZE SHAFT SINKING IN CHINA

    Institute of Scientific and Technical Information of China (English)

    张铭; 翁家杰; 夏正明

    1991-01-01

    This paper gives a brief review of the development of shaft sinking by artificial ground freezing since 1949 when new China was founded. Several shaft freezing schemes which have been successfully applied from the economic and safe viewpoints are presented. Current technology and some innovative techniques,especially the shah lining which have experienced major improvements over the last four decades,are briefly reviewed. The technique of the in-situ pour concrete incorporating ailica fume with higher early strength under low temperature curing conditions is described. The temperature field in shah freezing and its finite difference solution are given in this paper. A recently developed method combining freeze wall model test with back analysis technique based on numerical simulation is also described.

  2. Seismic Analysis of Reinforced Concrete Shaft Support Water Storage Tank

    Directory of Open Access Journals (Sweden)

    Bharti Tekwani

    2016-05-01

    Full Text Available This paper compares the results of Seismic Analysis of Reinforced Concrete Shaft Support Water Storage Tank carried out in accordance with IS: 1893- 1984 and IS: 1893-2002 (Part-2 draft code. The analysis is carried out for shaft supported water tank of 500,750 and 1000 Cu.m capacity, located in four seismic zones (Zone-II, Zone -III, Zone-IV, Zone-V and on three different soil types (Hard rock, Medium soil, Soft soil. Further, 1000 kl tank for conditions - tank full, tank empty are also considered in this study. The analysis was performed using MAT LAB. The parameters of comparison include base shears, base moments and time history analysis. The above models are analyzed for different time history data such as El Centro, Kobe, Ji-Ji, Erzincan. The comparison is made between the structural responses of one mass and two mass models of above capacity.

  3. Dynamics of a supercritical composite shaft mounted on viscoelastic supports

    Science.gov (United States)

    Montagnier, O.; Hochard, C.

    2014-01-01

    The damping in a carbon fiber reinforced plastic (CFRP) laminate is greater than that which occurs in most metallic materials. In the supercritical regime, the damping can trigger unstable whirl oscillations, which can have catastrophic effects. The vibrations occurring in a supercritical composite drive shaft are investigated here in order to predict instabilities of this kind. A simply supported carbon/epoxy composite tube mounted on viscoelastic supports is studied, using an approximation of the Rayleigh-Timoshenko equation. The damping process is assumed to be hysteretic. The composite behavior is described in terms of modulus and loss factor, taking homogenized values. The critical speeds are obtained in several analytical forms in order to determine the effects of factors such as the rotatory inertia, the gyroscopic forces, the transverse shear and the supports stiffness. Assuming that the hysteretic damping can be expressed in terms of the equivalent viscous model, the threshold speed is obtained in the form of an analytical criterion. The influence of the various factors involved is quantified at the first critical speed of a subcritical composite shaft previously described in the literature. The influence of the coupling mechanisms on the unsymmetrical composite laminate and the end fittings is also investigated using a finite element model. None of these parameters were found to have a decisive influence in this case. Those having the greatest effects were the transverse shear and the supports stiffness. The effects of the composite stacking sequence, the shaft length and the supports stiffness on the threshold speed were then investigated. In particular, drive shafts consisting only of ±45° or ±30° plies can be said to be generally unstable in the supercritical regime due to their very high loss factors.

  4. Robust design of a polygonal shaft-hub coupling

    Directory of Open Access Journals (Sweden)

    R. Citarella

    2015-10-01

    Full Text Available In this work, the Taguchi method is applied for the optimal choice of design parameter values for a polygonal shaft-hub coupling. The objective is to maximize a performance function, minimizing, at the same time, its sensitivity to noises factors (robust design. The Design of Experiments (DoE is adopted to set up a plan of numerical experiments, whose different configurations are simulated using the Boundary Element Method (BEM

  5. Penile Shaft : An Unusual Location For Skin Tags

    Directory of Open Access Journals (Sweden)

    Thami Gurvinder P

    2003-01-01

    Full Text Available Skin tags or acrochordons, commonly observed in the flexural surfaces and various folds of skin, are more frequently encountered in presence of obesity, diagetes and old age. Although lesions are quite characteristic clinically, at times these need to be differentiated from warts, fibromas and other benign tumors of skin and their appendages. A rare case with presence of skin tags over the shaft of penis is described.

  6. Correlation of operating parameters on turbine shaft vibrations

    Science.gov (United States)

    Dixit, Harsh Kumar; Rajora, Rajeev

    2016-05-01

    The new generation of condition monitoring and diagnostics system plays an important role in efficient functioning of power plants. In most of the rotating machine, defects can be detected by such a system much before dangerous situation occurs. It allows the efficient use of stationary on-line continuous monitoring system for condition monitoring and diagnostics as well. Condition monitoring of turbine shaft can not only reduce expenses of maintenance of turbo generator of power plants but also prevents likely shutdown of plant, thereby increases plant load factor. Turbo visionary parameters are essential part of health diagnosis system of turbo generator. Particularly steam pressure, steam temperature and lube oil temperature are important parameters to monitor because they are having much influence on turbine shaft vibration and also governing systems are available for change values of those parameters. This paper includes influence of turbo visionary parameters i.e., steam temperature, steam pressure, lube oil temperature, turbine speed and load on turbine shaft vibration at turbo generator at 195 MW unit-6,Kota Super Thermal Power Station by measuring vibration amplitude and analyze them in MATLAB.

  7. Measurement of vibratory motions of gears supported by compliant shafts

    Science.gov (United States)

    Kang, Ma Ru; Kahraman, Ahmet

    2012-05-01

    In this paper, an improved accelerometer-based method is proposed for measurement of motions of parallel-axis gears in torsional, translational and rotational directions. This method uses a family of triaxial accelerometers that are mounted on a shaft flange next to the gears at a given radius. Acceleration signals from the accelerometers are processed using a novel formulation to quantify the motions of a gear in the torsional, rotational (rocking), transverse (line-of-action and off-line-of-action) and axial directions. This measurement system is applied to example spur and helical gear pairs held by shafts having different bending compliances. The experimental results indicate that the proposed accelerometer-based measurement methodology is effective in measuring not only the torsional motions but also the other types of translational, rotational and axial motions of a gear as well as the dynamic transmission error. They also point to the influence of the shaft flexibility on gear vibration amplitudes in these directions.

  8. Fracture Union in Closed Interlocking Nail in Humeral Shaft Fractures

    Institute of Scientific and Technical Information of China (English)

    Ramji Lal Sahu; Rajni Ranjan; Ajay Lal

    2015-01-01

    Background:Fracture shaft humerus is a major cause of morbidity in patients with upper extremity injuries.The aim of this study was to evaluate the outcome of interlocking nail in humeral shaft fractures.Methods:This study was conducted in the Department of Orthopedic Surgery in SMS and R Sharda University from January 2010 to November 2013.Seventy-eight patients were recruited from emergency and out-patient department having a close fracture of humerus shaft.All patients were operated under general anesthesia and closed reamed interlocking nailing was done.All patients were followed for 9 months.Results:Out of 78 patients,69 patients underwent union in 90-150 days with a mean of 110.68 days.Complications found in four patients who had nonunion,and five patients had delayed union,which was treated with bone grafting.All the patients were assessed clinically and radiologically for fracture healing,joint movements and implant failure.The results were excellent in 88.46% and good in 6.41% patients.Complete subjective,functional,and clinical recovery had occurred in almost 100% of the patients.Conclusions:The results of the present study indicates that in the presence of proper indications,reamed antegrade intramedullary interlocked nailing appears to be a method of choice for internal fixation of osteoporotic and pathologic fractures.

  9. HOC Based Blind Identification of Hydroturbine Shaft Volterra System

    Directory of Open Access Journals (Sweden)

    Bing Bai

    2017-01-01

    Full Text Available In order to identify the quadratic Volterra system simplified from the hydroturbine shaft system, a blind identification method based on the third-order cumulants and a reversely recursive method are proposed. The input sequence of the system under consideration is an unobservable independent identically distributed (i.i.d., zero-mean and non-Gaussian stationary signal, and the observed signals are the superposition of the system output signal and Gaussian noise. To calculate the third-order moment of the output signal, a computer loop judgment method is put forward to determine the coefficient. When using optimization method to identify the time domain kernels, we combined the traditional optimization algorithm (direct search method with genetic algorithm (GA and constituted the hybrid genetic algorithm (HGA. Finally, according to the prototype observation signal and the time domain kernel parameters obtained from identification, the input signal of the system can be gained recursively. To test the proposed method, three numerical experiments and engineering application have been carried out. The results show that the method is applicable to the blind identification of the hydroturbine shaft system and has strong universality; the input signal obtained by the reversely recursive method can be approximately taken as the random excitation acted on the runner of the hydroturbine shaft system.

  10. Detection of cracks in shafts with the Approximated Entropy algorithm

    Science.gov (United States)

    Sampaio, Diego Luchesi; Nicoletti, Rodrigo

    2016-05-01

    The Approximate Entropy is a statistical calculus used primarily in the fields of Medicine, Biology, and Telecommunication for classifying and identifying complex signal data. In this work, an Approximate Entropy algorithm is used to detect cracks in a rotating shaft. The signals of the cracked shaft are obtained from numerical simulations of a de Laval rotor with breathing cracks modelled by the Fracture Mechanics. In this case, one analysed the vertical displacements of the rotor during run-up transients. The results show the feasibility of detecting cracks from 5% depth, irrespective of the unbalance of the rotating system and crack orientation in the shaft. The results also show that the algorithm can differentiate the occurrence of crack only, misalignment only, and crack + misalignment in the system. However, the algorithm is sensitive to intrinsic parameters p (number of data points in a sample vector) and f (fraction of the standard deviation that defines the minimum distance between two sample vectors), and good results are only obtained by appropriately choosing their values according to the sampling rate of the signal.

  11. Effects of Discrete Damping on the Dynamic Behaviour of Rotating Shaft through Extended Lagrangian Formulation

    Science.gov (United States)

    Rastogi, Vikas

    2016-09-01

    The main focus of the paper is touted as effects of discrete damping on the dynamic analysis of rotating shaft. The whole analysis is being carried out through extended Lagrangian formulation for a discrete - continuous system. The variation formulation for this system is possible, considering the continuous system as one-dimensional. The generalized formulation for one dimensional continuous rotary shaft with discrete external damper has been obtained through principle of variation. Using this extended formulation, the invariance of umbra-Lagrangian density through extended Noether's theorem is achieved. Rayleigh beam model is used to model the shaft. Amplitude equation of rotor is obtained theoretically and validated through simulation results. The simulation results reveal the important phenomena of limiting dynamics of the rotor shaft, which is due to an imbalance of material damping and stiffness of the rotor shaft. The regenerative energy in the rotor shaft, induced due to elasticity/stiffness of the rotor shaft, is dissipated partially through the in-span discrete damper and also through the dissipative coupling between drive and the rotor shaft. In such cases, the shaft speed will not increase with increase in excitation frequency of the rotor but the slip between the drive and the shaft increases due to loading of drive.

  12. Effects of Discrete Damping on the Dynamic Behaviour of Rotating Shaft through Extended Lagrangian Formulation

    Directory of Open Access Journals (Sweden)

    Rastogi Vikas

    2016-09-01

    Full Text Available The main focus of the paper is touted as effects of discrete damping on the dynamic analysis of rotating shaft. The whole analysis is being carried out through extended Lagrangian formulation for a discrete – continuous system. The variation formulation for this system is possible, considering the continuous system as one-dimensional. The generalized formulation for one dimensional continuous rotary shaft with discrete external damper has been obtained through principle of variation. Using this extended formulation, the invariance of umbra-Lagrangian density through extended Noether’s theorem is achieved. Rayleigh beam model is used to model the shaft. Amplitude equation of rotor is obtained theoretically and validated through simulation results. The simulation results reveal the important phenomena of limiting dynamics of the rotor shaft, which is due to an imbalance of material damping and stiffness of the rotor shaft. The regenerative energy in the rotor shaft, induced due to elasticity/stiffness of the rotor shaft, is dissipated partially through the in-span discrete damper and also through the dissipative coupling between drive and the rotor shaft. In such cases, the shaft speed will not increase with increase in excitation frequency of the rotor but the slip between the drive and the shaft increases due to loading of drive.

  13. Shafting Alignment Computing Method of New Multibearing Rotor System under Specific Installation Requirement

    Directory of Open Access Journals (Sweden)

    Qian Chen

    2016-01-01

    Full Text Available The shafting of large steam turbine generator set is composed of several rotors which are connected by couplings. The computing method of shafting with different structure under specific installation requirement is studied in this paper. Based on three-moment equation, shafting alignment mathematical model is established. The computing method of bearing elevations and loads under corresponding installation requirements, where bending moment of each coupling is zero and there exist preset sag and gap in some couplings, is proposed, respectively. Bearing elevations and loads of shafting with different structure under specific installation requirement are calculated; calculation results are compared with installation data measured on site which verifies the validity and accuracy of the proposed shafting alignment computing method. The above work provides a reliable approach to analyze shafting alignment and could guide installation on site.

  14. Stiffness Characteristics of Fibre-reinforced Composite Shaft Embedded with Shape Memory Alloy Wires

    Directory of Open Access Journals (Sweden)

    K. Gupta

    2003-04-01

    Full Text Available Frequent coast up/coast down operations of rotating shafts in the power and aerospace industry expose the flexible rotors to the risk of fatigue failures. Resonant vibrations during passage through critical speeds induce large stresses that may lead to failures. In this paper, the use of nitinol [shape memory alloy (SMA] wires in the fibre-reinforced composite shaft, for the purpose ofmodifying shaft stiffness properties to avoid such failures, is discussed. A setup has been developed to fabricate the composite shaft (made of fibre glass and epoxy resin embedded with pre-stressed SMA wires. Experiments have been carried out on the shaft to estimate the changes in the natural frequency of the composite shaft due to activation and deactivation ofSMA wires. The comparisonofthe experimental results with the established analytical results indicates feasibility ofvibration control using the special properties of SMA wires.

  15. Dynamic Analysis of Rotating Shaft Subjects to Slant Crack with Experimentation and ANSYS Validation

    Directory of Open Access Journals (Sweden)

    Rushikesh V. Dhokate

    2014-09-01

    Full Text Available The paper contents the dynamic study of rotating shaft with slant crack on surface of shaft. Slant cracks are prepared artificially on surface of shaft with material EN8. In this study, crack location taken on shaft 150 mm from motor side and also for effective study healthy shaft of EN8 material is taken. Experimental results are taken with the help of FFT analyzer. Analysis is carried out from these results and finally these results are validated in FEA software i. e. ANSYS14 software. These validated results with graphs are explained in this paper. The experimentation is also done on healthy shaft of EN8 material for analysis. This paper mainly focused on validation of experimental results with ANSYS software.

  16. INVESTIGATION OF SIMULATION EXPERIMENT ON ACTIVE CONTROL OF TORSIONAL VIBRATION IN A TURBOGENERATOR SHAFT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    Hao Zhiyong; Gao Wenzhi

    2004-01-01

    According to the theoretical analysis and calculation on the base of continuous mass system, the simulation experimental investigation on active control of torsional vibration in a turbogenerator shaft system is conducted.A test installation with the excitation of generator motor and multi-stepped shaft system is established to simulate the torsional vibration of a turbogenerator rotor shaft system, and to examine the active control strategy presented.Some useful results are reached in the experimental study.

  17. SUPPORTING PROCEDURE AND FIELD MEASUREMENT IN THE SHAFT THROUGH GLIDING TECTONIC GROUND

    Institute of Scientific and Technical Information of China (English)

    XIAJianzhong; TENGNianbao

    1995-01-01

    The paper describes mechanical properties and deformation features of shaft adjoining rocks in gliding tectonic ground and presents the shaft-fupporting procedure of smooth-wall cushion blasting ,preliminary bolting and shotcreting and pouring reinforced concrete liner in one-time-whole-section in the basis of adjoining rock deformations measured dynamically in site ,Field measurements of the pressure exerted on shaft wall show that this supporting procedure has enough safety reserve to meet the safety repuirements in mining production.

  18. Percutaneous Kirschner wire (K-wire) fixation for humerus shaft fractures in children: A treatment concept

    OpenAIRE

    2013-01-01

    Background: Fractures of the humeral shaft are uncommon, representing less than 10 percent of all fractures in children. Humeral shaft fractures in children can be treated by immobilisation alone. A small number of fractures are unable to be reduced adequately or maintained in adequate alignment, and these should be treated surgically. In the present study, Kirschner wires (K-wire) were used to achieve a closed intramedullary fixation of humeral shaft fractures. The objective of this study wa...

  19. Gearbox Reliability Collaborative Investigation of Gearbox Motion and High-Speed-Shaft Loads

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jon [National Renewable Energy Lab. (NREL), Golden, CO (United States); Guo, Yi [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sethuraman, Latha [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-03-18

    This paper extends a model-to-test validation effort to examine the effect of different constant rotor torque and moment conditions and intentional generator misalignment on the gearbox motion and high-speed-shaft loads. Fully validating gearbox motion and high-speed-shaft loads across a range of test conditions is a critical precursor to examining the bearing loads, as the gearbox motion and high-speed-shaft loads are the drivers of these bearing loads.

  20. Compensation Method of Laser Drifting by Atmosphere Turbulence in Large Shafting Aligning

    Institute of Scientific and Technical Information of China (English)

    CAO Guo-hua; SU Cheng-zhi; XU Hong-ji

    2006-01-01

    Instead of the rotor shafting line, visible laser beam, as a centering and adjusting benchmark of rotor bearing groove or static components, has been used to examine and repair the high precision shafting in many industry areas. Atmosphere turbulence is one of the important factors that affect shafting alignment precision. A correcting method is proposed in this paper, which monitors the light target to measure the drift of laser direetrix in real time and compensates the error using beeline correction.

  1. Pediatric femoral shaft fractures treated by flexible intramedullary nailing

    Institute of Scientific and Technical Information of China (English)

    K.C.Kapil Mani; R.C.Dirgha Raj; Acharya Parimal

    2015-01-01

    Background:Nowadays pediatric femoral fractures are more commonly managed with operative treatment rather than conservative treatment because of more rapid recovery and avoidance of prolonged immobilization.Children between the ages of 5-13 years are treated either by traction plus hip spica and flexible/elastic stable retrograde intramedullary nail,or external fixators in the case of open fractures.The aim of this study is to evaluate the outcome of pediatric femoral shaft fractures treated by stainless steel flexible intramedullary nail in children between 5 and 13 years of age.Methods:There were 32 cases of femoral shaft fractures which were all fixed with stainless steel flexible intramedullary nail under fluoroscopy.Long leg cast was applied at the time of fixation.Partial weight bearing was started 2 weeks after surgery.Patients were evaluated in follow-up study to observe the alignment of fracture,infection,delayed union,nonunion,limb length discrepancy,motion of knee joint,and time to unite the fracture.Results:We were able to follow up 28 out of 32 patients.The patients were 8.14 years of age on average.The mean hospital stay after operation was 4 days and fracture union time was 9.57 weeks.There were 3 cases of varus angulation,2 cases of anterior angulation,and 4 cases of limb lengthening.Conclusion:Patients aged between 5 and 13 years treated with flexible intramedullary nail for closed femoral shaft fracture have rapid union and recovery,short rehabilitation period,less immobilization and psychological impact,and cost-effective.

  2. Research and development on cutting scale machine in the coalmine shaft

    Institute of Scientific and Technical Information of China (English)

    REN Bao-cai(任保才)

    2004-01-01

    The deposit scale in the coal mine shaft usually causes serious accidents, such as making rope broken, cage seized or dropped. To solve this kind of problems, the research of the cutting scale mechanism was made, and a new type of removal scale equipment was made with using imported hard alloy material. The cutting experiment and actual cutting show that it can adapt to abominable condition in the shaft, such as narrow space, wet and excessive shaft crevice water and so on, and can work safely and reliably, and has high cutting scale efficiency. It can also cut out the deposit scale in the circular section of shaft.

  3. Efficiency and quality of inductive heating and quenching of planetary shafts

    Directory of Open Access Journals (Sweden)

    B. Kosec

    2012-01-01

    Full Text Available Presented work discusses a complex process of inductive heating and quenching of carbon steel planetary shafts for diesel engine starters. On the measurements base of temperature fi elds on the surface of the planetary shafts by thermographic camera and theoretical knowledge, a mathematical model for temperature conditions determination in the shaft during the entire process of heating and quenching was carried out. On the basis of developed mathematical model a computer program was developed, and used for analyses and induction hardening process optimization of planetary shafts.

  4. External fixation in the treatment of open tibial shaft fractures

    Directory of Open Access Journals (Sweden)

    Golubović Zoran

    2008-01-01

    Full Text Available Background/Aim. Besides the conquasant fractures, open tibia shaft fractures belong to the group of the most severe fractures of tibia. Open tibia shaft fracture is one of the most common open fractures of long bones. They most frequently occur as a result of traffic accidents caused by the influence of a strong direct force. Methods. Within the period from January, 2000 to December 31, 2005. at the Clinic for Orthopaedics and Traumatology, Clinical Center Nis, 107 patients with open tibial fractures were treated. We analyzed 96 patients with open tibial fracture. In the series analyzed, the male sex was prevalent - there were 74 men (77.08%. The mean age was 47.3 years. The youngest patient was 17 years old, while the oldest patient was 79. According to the classification of the Gustilo et al. in the analysed group there were 30 (31.25% open tibial fractures of the I degree, 31 (32.29% of the II degree, 25 (26.05% of the III A degree, 8 (8.33% of the III B degree and 2 (2.08% of the III C degree. In 95 of the patients the treatment of open tibia shaft fractures consisted of the surgical treatment of wound and the external fixation of the fractured bone using "Mitkovic" type external fixator with a convergent method of pin applications. One primary amputations had been done in patients with grade IIIC open tibial fracture with large soft tissue defect. Results. Of the 96 open tibial fractures available for follow-up, 73 (76.04% healed without severe complications (osteitis, pseudoarthrosis, valgus malunion and amputation. Ther were nine (9.38% soft tissue pin track infections and six (6.25% superficial wound infections. The mean time of union was 21 (14-36 week. Among severe local complications associated with open tibial fractures, in eight patients (8.33% was registered osteitis, and in nine patients (9.38% fracture nonunion and the development of pseudoarthrosis. Three of the patients (3.13% had more than 10 degree valgus malunion. In one

  5. Experimental study on a magnetofluid sealing liquid for propeller shaft

    Institute of Scientific and Technical Information of China (English)

    ZHAO Chang-fa; SUN Rong-hua; ZHENG Jin-xing

    2003-01-01

    The selecting and preparing method of the basic material of magnetic fluid was introduced. By using a chemical method, the magnetic micropowder Fe3O4 was successfully yielded, and an oil-base as a working carrier and dispersing agent was determined. The preparation process of the magnetic fluid and prescription of the oil-base magnetic fluid were discussed. The simulation experimental rig of magnetic fluid sealing for propeller shaft was designed. The sealing ability experiment was conducted and results were analyzed. The pressure of sealing is up to 2 Mpa.

  6. Analysis of metal forming process of a hollowed gear shaft

    Directory of Open Access Journals (Sweden)

    J. Tomczak

    2012-10-01

    Full Text Available This paper presents the results of numerical analysis of forming a hollowed gear shaft forging, used in automotive industry. Numerical simulations of the process were made by means of finite elements method (FEM in conditions of three dimensional state of strain with consideration of thermal phenomena. During calculations, geometrical parameters of the obtained products were analyzed, distributions of strains and temperatures were determined. The process force parameters were also given. In the result of conducted research works, it was stated that it is possible to form in a rotary way axi-symmetrical hollowed forgings.

  7. Shaft centre orbit for dynamically loaded radial bearings

    DEFF Research Database (Denmark)

    Klit, Peder; Vølund, Anders

    2002-01-01

    The aim of this work is to demonstrate how to utilize the bearings damping coefficients to estimate the orbit for a dynamically loaded journal bearing. The classical method for this analysis was developed by Booker in 1965 Booker1 and described further in 1972 Booker2. Several authors have refined...... seventies Jorgen W. Lund pointed out in lecture notes that the dynamic damping coefficients of the bearing could be used to find the shaft orbit for dynamically loaded bearings. For simplicity the "Short-Width-Journal-Bearing Theory" is used as a basis for finding the damping coefficients in this work...

  8. The Tilt of the Elevator Shaft of Bunker Skutina

    Directory of Open Access Journals (Sweden)

    Pavel KALENDA

    2014-06-01

    Full Text Available The measurement of deformations of the elevator shaft in the Skutina fortress between the 2nd floor and the depth of 33 m below the surface took place in 2009. These measurements showed that, in addition to the tides, the diurnal thermoelastic wave deforms the body of the bunker, particularly in the NS direction. The amplitude of this deformation depends mainly on the cloudiness (opposite to the irradiance. Morning and evening deformation curves depend mainly on the time of sunrise and the geometry of the body of the bunker (irradiance of the bunker walls and less of the outside temperature.

  9. Radial head dislocation during proximal radial shaft osteotomy.

    Science.gov (United States)

    Hazel, Antony; Bindra, Randy R

    2014-03-01

    The following case report describes a 48-year-old female patient with a longstanding both-bone forearm malunion, who underwent osteotomies of both the radius and ulna to improve symptoms of pain and lack of rotation at the wrist. The osteotomies were templated preoperatively. During surgery, after performing the planned radial shaft osteotomy, the authors recognized that the radial head was subluxated. The osteotomy was then revised from an opening wedge to a closing wedge with improvement of alignment and rotation. The case report discusses the details of the operation, as well as ways in which to avoid similar shortcomings in the future.

  10. Final Reclamation Report: Basalt Waste Isolation Project exploratory shaft site

    Energy Technology Data Exchange (ETDEWEB)

    Brandt, C.A.; Rickard, W.H. Jr.

    1990-06-01

    The restoration of areas disturbed by activities of the Basalt Waste Isolation Project (BWIP) constitutes a unique operation at the US Department of Energy's (DOE) Hanford Site, both from the standpoint of restoration objectives and the time frame for accomplishing these objectives. The BWIP reclamation program comprises three separate projects: borehole reclamation, Near Surface Test Facility (NSTF) reclamation, and Exploratory Shaft Facility (ESF) reclamation. The main focus of this report is on determining the success of the revegetation effort 1 year after work was completed. This report also provides a brief overview of the ESF reclamation program. 21 refs., 7 figs., 14 tabs.

  11. Building up a Mathematical Model of Shaftes System and CAD for Linked Tetra—Shaft and Double—Cantilever Flat Flap Gate

    Institute of Scientific and Technical Information of China (English)

    FuQ满怀; ZhaoZe-bin; 等

    1999-01-01

    Linked tetra-shaft and double-cantilever flat flap gate is a new type of structure in water conservancy projects,but the traditional method is now adopted in its design.In order to the application and dissemination of the type of sluice,this paper researches the difficult points of design advance,through researching the motion locus & stress coundition of linked tetra-shaft system.The writer will build up the mathmatical model and handle it with the computer.Thus,we can achieve the modern desing on the basis of the software of linked tetra-shaft system development.

  12. Building up a Mathematical Model of Shaftes System and CAD for Linked Tetra-Shaft and Double-Cantilever Flat Flap Gate

    Institute of Scientific and Technical Information of China (English)

    1999-01-01

    Linked tetra-shaft and double-cantilever flat flap gate is a new type of structure in water conservancy projects ,but the traditional method is now adopted in its design. In order to the application and dissemination of the type of sluice ,this paper researches the difficult points of design advance ,through researching the mo- tion locus & stress coundition of linked tetra-shaft system. The writer will build up the mathmatical model and handle it with the computer. Thus, we can achieve the modern desing on the basis of the software of linked tetra-shaft system development.

  13. Hydrodynamically Lubricated Rotary Shaft Having Twist Resistant Geometry

    Science.gov (United States)

    Dietle, Lannie; Gobeli, Jeffrey D.

    1993-07-27

    A hydrodynamically lubricated squeeze packing type rotary shaft with a cross-sectional geometry suitable for pressurized lubricant retention is provided which, in the preferred embodiment, incorporates a protuberant static sealing interface that, compared to prior art, dramatically improves the exclusionary action of the dynamic sealing interface in low pressure and unpressurized applications by achieving symmetrical deformation of the seal at the static and dynamic sealing interfaces. In abrasive environments, the improved exclusionary action results in a dramatic reduction of seal and shaft wear, compared to prior art, and provides a significant increase in seal life. The invention also increases seal life by making higher levels of initial compression possible, compared to prior art, without compromising hydrodynamic lubrication; this added compression makes the seal more tolerant of compression set, abrasive wear, mechanical misalignment, dynamic runout, and manufacturing tolerances, and also makes hydrodynamic seals with smaller cross-sections more practical. In alternate embodiments, the benefits enumerated above are achieved by cooperative configurations of the seal and the gland which achieve symmetrical deformation of the seal at the static and dynamic sealing interfaces. The seal may also be configured such that predetermined radial compression deforms it to a desired operative configuration, even through symmetrical deformation is lacking.

  14. A novel shaft-less double suction mini pump

    Institute of Scientific and Technical Information of China (English)

    NISHI; Michihiro

    2010-01-01

    A novel double suction shaft-less mini pump was developed for heat control of small energy systems in this study.The mini pump impeller with an exit diameter of 40 mm was combined with the motor rotor supported by the hybrid dynamic bearing.The specific speed of the pump was 125 min-1 m3 min-1 m.The hydraulic performance of the pump was investigated experimen-tally under four rotational speeds.From the test results,it was recognized that the pump could provide a flow discharge of 5 L/min and head of 1.5 m,which are applicable for the heat control system of a 3 kW fuel cell.A three-dimensional turbulent flow simulation in the pump was also conducted near the design point.The numerical results showed that the average hydraulic performance of the mini pump was predicted reasonably.From the internal flow simulation,it was revealed that the favorable inflow condition upstream of impeller inlet could be attained by applying the double suction shaft-less design for the mini pump.

  15. Coke Reactivity in Simulated Blast Furnace Shaft Conditions

    Science.gov (United States)

    Haapakangas, Juho; Suopajärvi, Hannu; Iljana, Mikko; Kemppainen, Antti; Mattila, Olli; Heikkinen, Eetu-Pekka; Samuelsson, Caisa; Fabritius, Timo

    2016-08-01

    Despite the fact that H2 and H2O are always present in the gas atmosphere of a blast furnace shaft, their role in the solution-loss reactions of coke has not been thoroughly examined. This study focuses on how H2 and H2O affect the reaction behavior and whether a strong correlation can be found between reactivity in the conditions of the CRI test (Coke Reactivity Index) and various simulated blast furnace shaft gas atmospheres. Partial replacement of CO/CO2 with H2/H2O was found to significantly increase the reactivity of all seven coke grades at 1373 K (1100 °C). H2 and H2O, however, did not have a significant effect on the threshold temperature of gasification. The reactivity increasing effect was found to be temperature dependent and clearly at its highest at 1373 K (1100 °C). Mathematical models were used to calculate activation energies for the gasification, which were notably lower for H2O gasification compared to CO2 indicating the higher reactivity of H2O. The reactivity results in gas atmospheres with CO2 as the sole gasifying component did not directly correlate with reactivity results in gases also including H2O, which suggests that the widely used CRI test is not entirely accurate for estimating coke reactivity in the blast furnace.

  16. Innovative phased array ultrasonic inspection solution for large rotor shafts

    Energy Technology Data Exchange (ETDEWEB)

    Maes, G.; Devos, D.; Tremblay, P., E-mail: gmaes@zetec.com [Zetec, Ville de Quebec, Quebec (Canada)

    2016-05-15

    The increasing needs of energy production led to new rotor shaft designs with larger dimensions. A new generation of nuclear power plants is already being deployed worldwide with such heavy components. Their implementation requires new inspection tools in order to guarantee the public safety and to ensure the quality of these critical parts. Due to the long sound path, conventional ultrasonic (UT) techniques cannot provide adequate detectability of the reference reflectors required by the existing codes. Also, some standards require multiple angle beams to be applied in addition to the straight beam inspection, and this leads to long inspection times. This paper will address the implementation and validation of phased array (PA) UT techniques, using a semi-flexible 2D array probe, for the inspection of large mono-block rotor shaft forgings. It will show how the beam focusing and steering capabilities of phased array UT probes can be used to overcome the issues occurring with conventional UT probes. Results of acoustic beam simulation, as well as detectability measurements and data acquisitions on representative test specimens will be presented and compared with conventional UT performance. Various aspects of the hardware and software specification will be addressed, as well as the potential reduction of the total inspection time. (author)

  17. How Does The Bone Shaft Geometry Affect its Bending Properties?

    Directory of Open Access Journals (Sweden)

    Kaveh P. Saffar

    2009-01-01

    Full Text Available In this research, ten fresh specimens of sheep tibiae were provided from slaughtered animals. Whole bone specimens were loaded in three-point bending according to standard wet bone test protocols. Mechanical properties were determined and compared with the results which were obtained from two dry bone tests. The results showed that fracture bending moment and bone extrinsic stiffness had significant relations with fracture cross-section dependent parameters (i.e., cross-section area and area moment of inertia. Where, fracture energy and ultimate strength did not have such a relation with these parameters. Finite element modeling of bone shaft was made with simplified geometry (neglecting cross-section variations along bone shaft in two steps: First, by elliptical cross-section and second, by circular cross-section, assuming linear elastic and isotropic properties for the specimens. Elastic (Young’s modulus and fracture load, evaluated from curves obtained from tests, were applied to the finite element model and close results of maximum stress in both test specimen and first (elliptical cross-section model showed up. There was an average difference of about 2% between ultimate strength of wet bone specimens and maximum (tensile stress occurred in the elliptical models. However, this value for circular models was about 16%.

  18. Anterior cruciate ligament reconstruction failure after tibial shaft malunion.

    Science.gov (United States)

    LaFrance, Russell M; Gorczyca, John T; Maloney, Michael D

    2012-02-17

    Anterior cruciate ligament (ACL) reconstruction is common, with >100,000 procedures performed each year in the United States. Several factors are associated with failure, including poor surgical technique, graft incorporation failure, overly aggressive rehabilitation, and trauma. Tibial shaft fracture is also common and frequently requires operative intervention. Failure to reestablish the anatomic alignment of the tibia may cause abnormal forces across adjacent joints, which can cause degenerative joint disease or attritional failure of the surrounding soft tissues. This article describes a case of ACL reconstruction failure after a tibial fracture that resulted in malunion. Excessive force across the graft from lower-extremity malalignment and improper tunnel placement likely contributed to the attritional failure of the graft. This patient required a staged procedure for corrective tibial osteotomy followed by revision ACL reconstruction. This article describes ACL reconstruction failure, tibial shaft malunions, their respective treatments, the technical details of each procedure, and the technical aspects that must be considered when these procedures are done in a staged manner by 2 surgeons.

  19. Plucked Human Hair Shafts and Biomolecular Medical Research

    Directory of Open Access Journals (Sweden)

    Kevin Schembri

    2013-01-01

    Full Text Available The hair follicle is a skin integument at the boundary between an organism and its immediate environment. The biological role of the human hair follicle has lost some of its ancestral importance. However, an indepth investigation of this miniorgan reveals hidden complexity with huge research potential. An essential consideration when dealing with human research is the awareness of potential harm and thus the absolute need not to harm—a rule aptly qualified by the Latin term “primum non nocere” (first do no harm. The plucked hair shaft offers such advantages. The use of stem cells found in hair follicles cells is gaining momentum in the field of regenerative medicine. Furthermore, current diagnostic and clinical applications of plucked hair follicles include their use as autologous and/or three-dimensional epidermal equivalents, together with their utilization as surrogate tissue in pharmacokinetic and pharmacodynamics studies. Consequently, the use of noninvasive diagnostic procedures on hair follicle shafts, posing as a surrogate molecular model for internal organs in the individual patient for a spectrum of human disease conditions, can possibly become a reality in the near future.

  20. Estimation of pretraumatic femoral antetorsion in bilateral femoral shaft fractures

    Energy Technology Data Exchange (ETDEWEB)

    Citak, Musa; Jagodzinski, Michael; Krettek, Christian; Huefner, Tobias [Hannover Medical School, Trauma Department, Hannover (Germany); Citak, Mustafa [BG-University Hospital Bergmannsheil, Department of Surgery, Bochum (Germany); Kendoff, Daniel; O' Loughlin, Padhraig F. [Hospital for Special Surgery, Orthopaedic Department, New York, NY (United States); Tavassol, Frank [Hannover Medical School, Department of Oral and Maxillofacial Surgery, Hannover (Germany)

    2009-12-15

    To describe a system for measurement of the pretraumatic femoral antetorsion angle post-bilateral femoral shaft fracture with the use of new imaging software which allows segmentation and three dimensional (3D) reconstruction of DICOM (digital imaging and communications in medicine) images. This case involved a 20-year-old patient with bilateral femoral shaft fractures. Following initial clinical examination, CT scans of both femurs were performed. Subsequently, the DICOM datasets were uploaded to the new software tool. Following segmentation and 3D reconstruction, pretraumatic femoral antetorsion angles were determined. Femoral antetorsion was described and assessed in two ways by referring to the intersection of the posterior condylar plane and (1) a line drawn between the center of the femoral head and femoral neck, (2) a line drawn between the centers of the femoral head and greater trochanter. Using these definitions, values for femoral antetorsion were found to be, respectively, 20 at the right fracture site and 19 on the left site, and 33 bilaterally. The investigators describe in this current technical report the use of new imaging software which enables the calculation of femoral AV following reduction of virtual fracture fragments which are created from standard DICOM images. We believe that this 3D reconstruction method of measuring the antetorsion angle can be integrated into a regular treatment algorithm and may potentially optimize clinical outcomes. (orig.)

  1. Submarine Propulsion Shaft Life: Probabilistic Prediction and Extension through Prevention of Water Ingress

    Science.gov (United States)

    2014-06-01

    Inspection. Reliability Engineering and System Safety , 271-292. 47 Shi, P., & Mahadevan, S. (2001). Damage Tolerance Approach for Probabilistic ...Submarine Propulsion Shaft Life: Probabilistic Prediction and Extension through Prevention of Water Ingress By Douglas E. Jonart M.S. Systems...number. 1. REPORT DATE 01 JUN 2014 2. REPORT TYPE 3. DATES COVERED 4. TITLE AND SUBTITLE Submarine Propulsion Shaft Life: Probabilistic

  2. Dynamic Analysis of Heavy Vehicle Medium Duty Drive Shaft Using Conventional and Composite Material

    Science.gov (United States)

    Kumar, Ashwani; Jain, Rajat; Patil, Pravin P.

    2016-09-01

    The main highlight of this study is structural and modal analysis of single piece drive shaft for selection of material. Drive shaft is used for torque carrying from vehicle transmission to rear wheel differential system. Heavy vehicle medium duty transmission drive shaft was selected as research object. Conventional materials (Steel SM45 C, Stainless Steel) and composite materials (HS carbon epoxy, E Glass Polyester Resin Composite) were selected for the analysis. Single piece composite material drive shaft has advantage over conventional two-piece steel drive shaft. It has higher specific strength, longer life, less weight, high critical speed and higher torque carrying capacity. The main criteria for drive shaft failure are strength and weight. Maximum modal frequency obtained is 919 Hz. Various harmful vibration modes (lateral vibration and torsional vibration) were identified and maximum deflection region was specified. For single-piece drive shaft the natural bending frequency should be higher because it is subjected to torsion and shear stress. Single piece drive shaft was modelled using Solid Edge and Pro-E. Finite Element Analysis was used for structural and modal analysis with actual running boundary condition like frictional support, torque and moment. FEA simulation results were validated with experimental literature results.

  3. Exploratory Shaft Seismic Design Basis Working Group report; Yucca Mountain Project

    Energy Technology Data Exchange (ETDEWEB)

    Subramanian, C.V. [Sandia National Labs., Albuquerque, NM (USA); King, J.L. [Science Applications International Corp., Las Vegas, NV (USA); Perkins, D.M. [Geological Survey, Denver, CO (USA); Mudd, R.W. [Fenix and Scisson, Inc., Tulsa, OK (USA); Richardson, A.M. [Parsons, Brinckerhoff, Quade and Douglas, Inc., San Francisco, CA (USA); Calovini, J.C. [Holmes and Narver, Inc., Las Vegas, NV (USA); Van Eeckhout, E. [Los Alamos National Lab., NM (USA); Emerson, D.O. [Lawrence Livermore National Lab., CA (USA)

    1990-08-01

    This report was prepared for the Yucca Mountain Project (YMP), which is managed by the US Department of Energy. The participants in the YMP are investigating the suitability of a site at Yucca Mountain, Nevada, for construction of a repository for high-level radioactive waste. An exploratory shaft facility (ESF) will be constructed to permit site characterization. The major components of the ESF are two shafts that will be used to provide access to the underground test areas for men, utilities, and ventilation. If a repository is constructed at the site, the exploratory shafts will be converted for use as intake ventilation shafts. In the context of both underground nuclear explosions (conducted at the nearby Nevada Test Site) and earthquakes, the report contains discussions of faulting potential at the site, control motions at depth, material properties of the different rock layers relevant to seismic design, the strain tensor for each of the waveforms along the shaft liners, and the method for combining the different strain components along the shaft liners. The report also describes analytic methods, assumptions used to ensure conservatism, and uncertainties in the data. The analyses show that none of the shafts` structures, systems, or components are important to public radiological safety; therefore, the shafts need only be designed to ensure worker safety, and the report recommends seismic design parameters appropriate for this purpose. 31 refs., 5 figs., 6 tabs.

  4. Response to Comment on "Whole-Genome Shotgun Sequencing of Mitochondria from Ancient Hair Shafts"

    DEFF Research Database (Denmark)

    Gilbert, Marcus Thomas Pius; Miller, Webb; Schuster, Stephan C.

    2008-01-01

    Debruyne et al. challenge the findings of our study and imply that we argue that hair shafts are an overall superior source of ancient DNA than bone. However, the authors are misreading and misinterpreting the conclusions of our study; we claim nothing further than that hair shaft represents...

  5. Humeral shaft fractures: Retrospective results of non-operative and operative treatment of 186 patients

    NARCIS (Netherlands)

    K.C. Mahabier (Kiran); L.M.M. Vogels (Lucas); B.J. Punt (Bas); G.R. Roukema (Gert); P. Patka (Peter); E.M.M. van Lieshout (Esther)

    2013-01-01

    textabstractBackground: Humeral shaft fractures account for 1-3% of all fractures and 20% of the fractures involving the humerus. The aim of the current study was to compare the outcome after operative and non-operative treatment of humeral shaft fractures, by comparing the time to radiological unio

  6. Global Dynamics of Shaft Lines Rotating in Surrounding Fluids Application to Thin Fluid Films

    Directory of Open Access Journals (Sweden)

    David Lornage

    2004-01-01

    a disc and a thin-walled shaft mounted on a hydrodynamic bearing. The second is intended for studying a more realistic structure composed of a shaft and a wheel coupled with a fluid film between the wheel and a casing. These applications make it possible to identify trends related to fluid effects and couplings between the flexible structural parts.

  7. Reducing Insertion Sites of Penetrating Multipolar Shaft Electrodes by Double Side Electrode Arrangement

    Science.gov (United States)

    2007-11-02

    Abstract-Micromachined devices with substrate-integrated elec- trodes are the key component in implantable microdevices for recording neuronal ...INSERTION SITES OF PENETRATING MULTIPOLAR SHAFT ELECTRODES BY DOUBLE SIDE ELECTRODE ARRANGEMENT T.Stieglitz1, P. Heiduschka2, M. Schuettler1, M. Gross1...and Subtitle Reducing Insertion Sites of Penetrating Multipolar Shaft Electrodes by Double Side Electrode Arrangement Contract Number Grant Number

  8. A methodology for lining design of circular mine shafts in different rock masses

    Institute of Scientific and Technical Information of China (English)

    Ozturk Hasan⇑; Guler Erdogan

    2016-01-01

    In this study, the finite element numerical modelling of 2D shaft sections in a Hoek–Brown medium are carried out in a non-hydrostatic stress state in an attempt to predict pressures developing around mine shafts. An iterative process of applying support pressure until observing no failure zone around the shaft is used to simulate the required lining support pressure for different shaft models. Later, regression anal-ysis is carried out to find a generic shaft pressure equation representing the rock mass and the stress state. Finally, the developed pressure equation which shows a good agreement with a case study is used in elastic‘thick-walled cylinder”equation to calculate the lining thickness required to prevent the devel-opment of a failure zone around the shaft. At the end of the study, a user-friendly object-oriented com-puter program‘Shaft 2D”is developed to simplify the rigorous shaft lining thickness calculation process.

  9. Cost-Effective Shaft Torque Observer for Condition Monitoring of Wind Turbines

    DEFF Research Database (Denmark)

    Perisic, Nevena; Kirkegaard, Poul Henning; Pedersen, Bo Juul

    2015-01-01

    Improvement of condition monitoring (CM) systems for wind turbines (WTs) and reduction of the cost of wind energy are possible if knowledge about the condition of different WT components is available. CM based on the WT drive train shaft torque signal can give a better understanding of the gearbox...... suggests a novel approach for low-cost, indirect monitoring of the shaft torque from standard WT measurements. The shaft torque is estimated recursively from measurements of generator torque, high speed shaft and low speed shaft angular speeds using the well-known Kalman filter theory. The performance...... of the augmented Kalman filter with fading memory (AKFF) is compared with the augmented Kalman filter (AKF) using simulated data of theWT for different load conditions, measurement noise levels andWT fault scenarios. A multiple-model algorithm, based on a set of different Kalman filters, is designed for practical...

  10. Fatigue damage of steam turbine shaft at asynchronous connections of turbine generator to electrical network

    Science.gov (United States)

    Bovsunovsky, A. P.

    2015-07-01

    The investigations of cracks growth in the fractured turbine rotors point out at theirs fatigue nature. The main reason of turbine shafts fatigue damage is theirs periodical startups which are typical for steam turbines. Each startup of a turbine is accompanied by the connection of turbine generator to electrical network. During the connection because of the phase shift between the vector of electromotive force of turbine generator and the vector of supply-line voltage the short-term but powerful reactive shaft torque arises. This torque causes torsional vibrations and fatigue damage of turbine shafts of different intensity. Based on the 3D finite element model of turbine shaft of the steam turbine K-200-130 and the mechanical properties of rotor steel there was estimated the fatigue damage of the shaft at its torsional vibrations arising as a result of connection of turbine generator to electric network.

  11. Analysis on volume invariability of metal circular shaft in torsion deformation

    Science.gov (United States)

    Yang, Li-Hong; Zou, Guang-Ping; He, Yun-Zeng; Wang, Hui

    2010-03-01

    Volume invariability of metal circular shaft in the case of small strain torsion deformation and large strain torsion deformation was, respectively, discussed experimentally and theoretically in this study. In accordance with the elastoplastic theory, it was given that the shear stress did not cause the change of volume in the large strain range. By utilizing torsion experiment with the solid shaft of low carbon steel, it was proved that metal can meet the conditions of the volume invariability in torsion deformation while the cumulative damage was not very serious. Volumetric deformation was analyzed in torsion of circular shaft in the perspective of micromechanics. Finally, Swift effect of solid circular shaft and tubular shaft of brass material were interpreted by using the formulae of elastoplastic critic load obtained from double-limb bar model test presented by Shanley.

  12. Floating Shaft Load Sharing Method for Face Gear Split Torque Transmission System

    Directory of Open Access Journals (Sweden)

    Ruifeng Wang

    2013-04-01

    Full Text Available In this study, the equivalent gear meshing error principle was used to analysis face gear split torque dynamics modeling, the mathematical model includes stiffness of shaft supporting, position of gears, backlashes, time-varying stiffness, damping, manufacturing error, assembly error. The result shows the floating shaft can achieved load sharing, the support stiffness is an important factor, decreasing the input shaft support stiffness, load sharing performance becomes better and vibration decreases by increasing the displacement of shaft. To study effect of errors, every errors change separately while others’ ideal. Every errors affect load sharing in different way, gear 4 manufacturing error and shaft 2 assembly error affect load sharing most, load sharing cannot achieve by decreasing one error.

  13. TECHNOLOGY OF HEAT TREATING-STRAIGHTENING OF LONG SHAFTS WITH LOW RIGIDITY

    Directory of Open Access Journals (Sweden)

    Antoni Świć

    2016-09-01

    Full Text Available The paper presents a new method of heat treating-straightening of long shafts with low rigidity. Analytical relationships for the determination of rectilinearity of shaft axis in heat treating- straightening are presented. A fixture for heat treating-straightening of shafts was developed. The experiment conducted as well as the calculations confirm high effectiveness of the developed method of heat treating-straightening of long shafts with low rigidity. Application of the developed technology of heat treating-straightening permits minimisation of the value of deflection of semi-finished product and stabilisation of the level of residual longitudinal stress, which results in enhanced operational accuracy of long shafts with low rigidity, improved quality and operation parameters of finished products.

  14. Pityriasis versicolor on penile shaft in a renal transplant recipient.

    Science.gov (United States)

    Ryu, Han-Won; Cho, Jae-We; Lee, Kyu-Suk

    2012-08-01

    Pityriasis versicolor is a superficial infection of the stratum corneum, which is caused by the Malassezia species. Tge Malassezia species consist of 12 subspecies, including M. furfur, M. pachydermatis, M. symphodialis and M. globasa. The Malassezia species are classified as a normal flora, particularly in the sebum rich areas of the skin, and they convert from saprophytic yeast to parasitic mycelial morpholgic form to cause clinical disease. But majorities of their distributions are in the upper back, the neck, the thighs, and the forearm, and not in the penis. It is well known that the renal transplant patients, who take immunosuppressive agents, have impairment in the protective cell mediated immunity. Thus, they are more susceptible to infectious diseases, such as a fungal infection. Therefore, clinical manifestations show higher incidence of disease, but they mostly occur in an expected distribution. We here report a case of pityriasis versicolor in a renal transplant recipient on penile shaft, which is an unusual area.

  15. On dynamic loads in parallel shaft transmissions. 2: Parameter study

    Science.gov (United States)

    Lin, Edward Hsiang-Hsi; Huston, Ronald L.; Coy, John J.

    1987-01-01

    Solutions to the governing equations of a spur gear transmission model, developed in NASA TM-100180 (AVSCOM TM-87-C-2), are presented. Factors affecting the dynamic load are identified. It is found that the dynamic load increases with operating speed up to a system natural frequency. At operating speeds beyond the natural frequency the dynamic load decreases dramatically. Also. it is found that the applied load and shaft inertia have little effect on the dynamic load. Damping and friction decrease the dynamic load. Finally, tooth stiffness has a significant effect on dynamic loading; the higher the stiffness, the lower the dynamic loading. Also, the higher the stiffness the higher the rotating speed required for dynamic response.

  16. Moving behavior of pellets in a pellet shaft furnace

    Institute of Scientific and Technical Information of China (English)

    梁儒全; 赫冀成

    2008-01-01

    The downward moving behavior of pellets in a 8 m2 pellet shaft furnace with an internal vertical air channel and a drying bed was studied by means of a visualized model(1-15) and a top model(1-1).The visualized model experiment shows that the downward movement of pellets can be regarded as plug flow approximately inside the furnace except for the lower region of cooling zone due to the influence of the drained hopper.The top model experiment reveals that the pellet sizes increase along the moving direction because of the percolation phenomenon,which results in a decrease of the resistance coefficient and an increase of the gas flow rate from the furnace wall toward the furnace center.

  17. Open tibial shaft fractures: II. Definitive management and limb salvage.

    Science.gov (United States)

    Melvin, J Stuart; Dombroski, Derek G; Torbert, Jesse T; Kovach, Stephen J; Esterhai, John L; Mehta, Samir

    2010-02-01

    Definitive treatment of open fractures of the tibial diaphysis is challenging. The high-energy nature of these fractures, as well as the contamination of the fracture site and devitalization of the soft-tissue envelope, greatly increases the risk of infection, nonunion, and wound complications. The goals of definitive treatment include wound coverage or closure; prevention of infection; restoration of length, alignment, rotation, and stability; fracture healing; and return of function. Advances in orthobiologics, modern plastic surgical techniques, and fracture stabilization methods, most notably locked intramedullary nailing, have led to improved prognosis for functional recovery and limb salvage. Despite improved union and limb salvage rates, the prognosis for severe type III open fracture of the tibial shaft remains guarded, and outcomes are often determined by patient psychosocial variables.

  18. Safe surgical technique: intramedullary nail fixation of tibial shaft fractures.

    Science.gov (United States)

    Zelle, Boris A; Boni, Guilherme

    2015-01-01

    Statically locked, reamed intramedullary nailing remains the standard treatment for displaced tibial shaft fractures. Establishing an appropriate starting point is a crucial part of the surgical procedure. Recently, suprapatellar nailing in the semi-extended position has been suggested as a safe and effective surgical technique. Numerous reduction techiques are available to achieve an anatomic fracture alignment and the treating surgeon should be familiar with these maneuvers. Open reduction techniques should be considered if anatomic fracture alignment cannot be achieved by closed means. Favorable union rates above 90 % can be achieved by both reamed and unreamed intramedullary nailing. Despite favorable union rates, patients continue to have functional long-term impairments. In particular, anterior knee pain remains a common complaint following intramedullary tibial nailing. Malrotation remains a commonly reported complication after tibial nailing. The effect of postoperative tibial malalignment on the clinical and radiographic outcome requires further investigation.

  19. Reactor coolant pump shaft seal behavior during station blackout

    Energy Technology Data Exchange (ETDEWEB)

    Kittmer, C.A.; Wensel, R.G.; Rhodes, D.B.; Metcalfe, R.; Cotnam, B.M.; Gentili, H.; Mings, W.J.

    1985-04-01

    A testing program designed to provide fundamental information pertaining to the behavior of reactor coolant pump (RCP) shaft seals during a postulated nuclear power plant station blackout has been completed. One seal assembly, utilizing both hydrodynamic and hydrostatic types of seals, was modeled and tested. Extrusion tests were conducted to determine if seal materials could withstand predicted temperatures and pressures. A taper-face seal model was tested for seal stability under conditions when leaking water flashes to steam across the seal face. Test information was then used as the basis for a station blackout analysis. Test results indicate a potential problem with an elastomer material used for O-rings by a pump vendor; that vendor is considering a change in material specification. Test results also indicate a need for further research on the generic issue of RCP seal integrity and its possible consideration for designation as an unresolved safety issue.

  20. Treatment of humeral shaft fractures with antegrade intramedullary locking nail.

    Science.gov (United States)

    Tsourvakas, Stefanos; Alexandropoulos, Christos; Papachristos, Ioannis; Tsakoumis, Grigorios; Ameridis, Nikolaos

    2011-12-01

    Antegrade interlocked humeral nailing for stabilization of humeral fractures was introduced many years ago, and studies on this method in the orthopedic literature have shown mixed results. The purpose of this investigation was to document the clinical outcome and complications associated with the use of an antegrade intramedullary nail (T2, Stryker) for the humeral fractures. Between 2005 and 2008, 52 fractures of the humeral shaft were treated operatively with this intramedullary nail in our department. Eight patients were polytraumatized, and four patients had an open fracture. The mean age of patients was 51.7 years. Forty-eight patients had an adequate duration of clinical follow-up (a mean of 18 months) for analysis. Complications were recorded, and the time to union was measured. Shoulder and elbow functions were assessed using the Constant Score and the Morrey Score, respectively. Forty-six fractures healed, with a mean time to clinical union of 10.3 weeks. Two patients developed pseudarthroses. There were four adverse events: two proximal screws backed out, one superficial infection at the insertion point, and one fracture at the distal end of the nail. Ninety-one percentage of patients had an excellent or good shoulder function. Five further operations were necessary: two for treatment of pseudarthroses, two for removal the backed out proximal screws, and one wound debridement for superficial infection. Antegrade humeral nailing is a valid therapeutic option for stabilization of humeral shaft fractures. By strictly adhering to the operation technique, the number and the severity of complications can be reduced. When good fracture alignment and stability are obtained, uneventful bone healing with good functional results is the rule.

  1. Antennas.

    Science.gov (United States)

    1982-03-03

    used to hold the central and cardan frames holding the gears and drive mechanisms which move the shaft which turns the small reflector. Then the "yoke...to be eliminated. In order to accommuodate the optical radiator, the construction of the cardan frame provides a free area near the center of the

  2. Torsional vibration measurements on rotating shaft system using laser doppler vibrometer

    Science.gov (United States)

    Xiang, Ling; Yang, Shixi; Gan, Chunbiao

    2012-11-01

    In this work, a laser torsional vibrameter was used to measure the torsion vibration of a rotating shaft system under electrical network impact. Based on the principles of laser Doppler velocimetry, the laser torsional vibrometer (LTV) are non-contact measurement of torsional oscillation of rotating shafts, offering significant advantages over conventional techniques. Furthermore, a highly complex shafting system is analyzed by a modified Riccati torsional transfer matrix. The system is modeled as a chain consisting of an elastic spring with concentrated mass points, and the multi-segments lumped mass model is established for this shafting system. By the modified Riccati torsional transfer matrix method, an accumulated calculation is effectively eliminated to obtain the natural frequencies. The electrical network impacts can activize the torsional vibration of shaft system, and the activized torsion vibration frequencies contained the natural frequencies of shaft system. The torsional vibrations of the shaft system were measured under electrical network impacts in laser Doppler torsional vibrometer. By comparisons, the natural frequencies by measurement were consistent with the values by calculation. The results verify the instrument is robust, user friendly and can be calibrated in situ. The laser torsional vibrometer represents a significant step forward in rotating machinery diagnostics.

  3. Application of Distributed Optical Fiber Sensing Technology in the Anomaly Detection of Shaft Lining in Grouting

    Directory of Open Access Journals (Sweden)

    Chunde Piao

    2015-01-01

    Full Text Available The rupture of the shaft lining caused by grouting has seriously undermined the safety in coal mining. Based on BOTDR distributed optical fiber sensing technology, this paper studied the layout method of optical fiber sensors and the anomaly detection method of the deformation and obtained the evolution law of shaft deformation triggered by grouting. The research results showed that the bonding problem of optical fiber sensors in damp environment could be effectively solved, by applying the binder consisting of sodium silicate and cement. Through BOTDR-based deformation detection, the real-time deformation of the shaft lining caused by grouting was immediately spotted. By comparing the respective strain of shaft lining deformation and concrete deformation, the risk range of shaft lining grouting was identified. With the additional strain increment of the shaft lining triggered by each process of grouting, the saturated condition of grouting volume in strata was analyzed, providing an important technical insight into the field construction and the safety of the shaft lining.

  4. METHOD OF ACHIEVING ACCURACY OF THERMO-MECHANICAL TREATMENT OF LOW-RIGIDITY SHAFTS

    Directory of Open Access Journals (Sweden)

    Antoni Świć

    2016-03-01

    Full Text Available The paper presents a method combining the processes of straightening and thermal treatment. Technological processes with axial strain were considered, for the case of heated material and without its heating. The essence of the process in the case of heated material consisted in the fact that if under tension all longitudinal forces in the first approximation are uniform - the same strains are generated. The presented technological approach, aimed at reducing the curvature of axial-symmetrical parts, is acceptable as the process of rough, preliminary machining, in the case of shafts with the ratio L/D≤100 (L – shaft length, d – shaft diameter and without a tendency of strengthening. To improve the accuracy and stability of geometric form of low-rigidity parts, a method was developed that combines the processes of straightening and heat treatment. The method consists in that axial strain – tension, is applied to the shaft during heating, and during cooling the product is fixed in a fixture, the cooling rate of the shaft being several-fold greater than that of the fixture. A device is presented for the realisation of the method of controlling the process of plastic deformation of low-rigidity shafts. In the case of the presented device and the adopted calculation scheme, a method was developed that permits the determination of the length of shaft section and of the time of its cooling.

  5. Intramedullary fixation of a femoral shaft fracture with preservation of an existing hip resurfacing prosthesis.

    Science.gov (United States)

    Bilkhu, A; Sisodia, G; Chakrabarty, G; Muralikuttan, K P

    2015-04-01

    Femoral neck fractures have been reported as a cause for failure in patients with a hip resurfacing arthroplasty. However, the incidence and management of fractures of the femoral shaft with an ipsilateral hip resurfacing arthroplasty is relatively absent in current literature. Although, the gold standard for the fixation of a closed femoral shaft fracture is with the use of an intramedullary nail, this can be a challenge in the presence of a hip resurfacing arthroplasty. We describe the case of anterograde intramedullary nail fixation for a femoral shaft fracture in a patient with an ipsilateral hip resurfacing arthroplasty in situ.

  6. Research on torsional capacity of composite drive shaft under clockwise and counter-clockwise torque

    Directory of Open Access Journals (Sweden)

    Yefa Hu

    2015-04-01

    Full Text Available The design of lay-up has a great influence on the mechanical properties of carbon fiber–reinforced plastic drive shaft. In this research, the stress states of each layer in the carbon fiber–reinforced plastic drive shaft were studied, which were different under opposite torque directions. The Tsai–Wu criterion was used to judge the torsional stability of the composite laminates. The data from finite element analysis showed that torsional capacities of a stacking sequence vary greatly with torque direction, and reasonable lay-up design can reduce the difference. Torque direction should not be ignored when designing a carbon fiber–reinforced plastic drive shaft.

  7. Femoral shaft fractures in children: elastic stable intramedullary nailing in 31 cases

    DEFF Research Database (Denmark)

    Houshian, Shirzad; Gøthgen, Charlotte Buch; Pedersen, Niels Wisbech;

    2004-01-01

    We report our experience with elastic stable intramedullary titanium nailing (ESIN) of femoral shaft fractures in children. From 1998 to 2001, we treated 31 children (20 boys), median age 6 (4-11) years, with ESIN for 29 closed and 2 grade I open femoral shaft fractures. We reviewed 30 children c...... in 6 children and 10 degrees of internal rotational deformity in 1 child. No angular deformity had occurred. Elastic stable intramedullary nailing seems to be a safe method for the treatment of femoral shaft fractures in children between 4 and 11 years of age....

  8. DYNAMIC ANALYSIS OF A SPATIAL COUPLED TIMOSHENKO ROTATING SHAFT WITH LARGE DISPLACEMENTS

    Institute of Scientific and Technical Information of China (English)

    朱怀亮

    2002-01-01

    The dynamic simulation is presented for an axial moving flexible rotating shafts,which have large rigid motions and small elastic deformation. The effects of the axial inertia,shear deformation, rotating inertia, gyroscopic moment, and dynamic unbalance areconsidered based on the Timoshenko rotating shaft theory. The equations of motion andboundary conditions are derived by Hamilton principle, and the solution is obtained by usingthe perturbation approach and cssuming mode method. This study confirms that the influenceof the axial rigid motion, shear deformation, slenderness ratio and rotating speed on thedynamic behavior of Timoshenko rotating shaft is evident, especially to a high-angularvelocity rotor.

  9. Technique to reduce the shaft torque stress at an induction machine

    Directory of Open Access Journals (Sweden)

    Adrian Tulbure

    2005-10-01

    Full Text Available For the active attenuation at load stress in the drive shaft, the control system should receive as input signal the instantaneous shaft torque value. In this context an intelligent observer for shaft tongue of mains operatea induction machine, which is able to responding by variation of LIF (Load Input Function[1] must be developed. Extensive computer simulation prove the effectiveness of the proposed solution. In order to obtain a practical validation, the stimulated regulator has been designed and tested in the Institute of Electrical Engineering in Clausthal/Germany [2]. This paper contains following parts: Developing the mathematical model, Practical realisation, Simulations and measurements, Evaluating the control solutions and Conclusions.

  10. Dynamic Formulations and Beating Phenomena of Rotating Euler—Bernoulli Flexible Shafts

    Institute of Scientific and Technical Information of China (English)

    朱怀亮

    2002-01-01

    In this paper,the intrinsic behavior of rotating Euler-Benoulli flexible shafts was studied due to coupled bending and torsional vibratuions,the equations of motion of the shaft with unbalanced eccentricity and visous material damping were derived by the Hamilton principle.The numerical solution was obtained using the perturbation approach and mode-assuming method.The influences of the coupled vibrations between the benging and torsion.the rotaing speed,material damping and the slenderness ratio of the shaft were analyzed.It is clearly shown that the beating phenomena can occur when the interaction of torsion and flexure is considered.

  11. Predictive analysis of shaft station radon concentrations in underground uranium mine: A case study.

    Science.gov (United States)

    Zhao, Guoyan; Hong, Changshou; Li, Xiangyang; Lin, Chunping; Hu, Penghua

    2016-07-01

    This paper presented a method for predicting shaft station radon concentrations in a uranium mine of China through theoretical analysis, mathematical derivation and Monte-Carlo simulation. Based upon the queuing model for tramcars, the average waiting time of tramcars and average number of waiting tramcars were determined, which were further used in developing the predictive model for calculating shaft station radon concentrations. The results exhibit that the extent of variation of shaft station radon concentration in the case study mine is not significantly affected by the queuing process of tramcars, and is always within the allowable limit of 200 Bq m(-3). Thus, the empirical limit of 100,000 T annual ore-hoisting yields has no value in ensuring radiation safety for this mine. Moreover, the developed model has been validated and proved useful in assessing shaft station radon levels for any uranium mine with similar situations.

  12. Investigation of Shaft Voltage in Wind Turbine Systems with Induction Generators

    Science.gov (United States)

    Adabi, Jafar; Zare, Firuz

    This paper presents the analysis of shaft voltage in different configurations of a doubly fed induction generator (DFIG) and an induction generator (IG) with a back-to-back inverter in wind turbine applications. Detailed high frequency model of the proposed systems have been developed based on existing capacitive couplings in IG & DFIG structures and common mode voltage sources. In this research work, several arrangements of DFIG based wind energy conversion systems (WES) are investigated in case of shaft voltage calculation and its mitigation techniques. Placements of an LC line filter in different locations and its effects on shaft voltage elimination are studied via Mathematical analysis and simulations. A pulse width modulation (PWM) technique and a back-to-back inverter with a bidirectional buck converter have been presented to eliminate the shaft voltage in a DFIG wind turbine.

  13. Implementation of the two-shaft industrial gas turbine; Einfuehrung der Zweiwellen-Gasturbine SGT-300

    Energy Technology Data Exchange (ETDEWEB)

    Engelbert, C.; Helas, D. [Siemens Energy Oil and Gas, Lincoln (United Kingdom)

    2012-07-01

    Since its market launching, the single shaft-industrial gas turbine SGT-300 with a performance of 7.9 MW{sub e}l. has been proven as a reliable propulsion machinery in the electric power generation. Based upon the experiences with this type of gas turbine, Siemens Energy Oil and Gas (Lincoln, United Kingdom) has developed a two-shaft industrial gas turbine being the subject of the contribution under consideration. The two-shaft industrial gas turbine SGT-300 MD has a mechanical performance of 8.2 MW. This device primarily is used as a propulsion machinery with a mechanical efficiency of 34.6 % in the oil and gas industry. The author of this contribution discusses the advantages of the two-shaft industrial gas turbine, the scope of development as well as the critical characteristics of construction. Furthermore, the testing results of this prototype are presented.

  14. Risk of femoral shaft and subtrochanteric fractures among users of bisphosphonates and raloxifene

    DEFF Research Database (Denmark)

    Vestergaard, P; Schwartz, F; Rejnmark, L;

    2010-01-01

    Prior studies have suggested an association between bisphosphonate use and subtrochanteric fractures. This cohort study showed an increased risk of subtrochanteric and femoral shaft fractures both before and after the start of drugs against osteoporosis including bisphosphonates. This may suggest...

  15. Dynamic modeling and analysis of axial vibration of a coupled propeller and shaft system

    Energy Technology Data Exchange (ETDEWEB)

    Li, Chenyang; Huang, Xiuchang; Hua, Hongxing [Shanghai Jiao Tong University, Shanghai (China)

    2016-07-15

    The dynamic and acoustic characteristics of a coupled propeller and shaft system which is modeled by the transfer matrix method are studied. The elasticity of the propeller is taken into consideration by employing the equivalent reduced modeling method. Thus the influence of the elastic propeller on the vibro-acoustic responses of the coupled system is investigated. To reduce the axial vibration of the coupled propeller-shaft system, the influence and location of the vibration isolator on the structural and acoustic responses is presented. Simulation results demonstrate that utilizing the relationship between the natural frequency of the propeller and the resonance frequency range of the shaft can control the vibration of the coupled system without other vibration control method. Utilizing a vibration isolator is another effective way to control vibration. The optimal position for the isolator installed between the shaft and the thrust bearing is investigated.

  16. RESEARCH AND MODEL DEVELOPMENT OF DRILLING AND BLASTING TECHNOLOGY PENETRATIONS OF VERTICAL SHAFTS

    Directory of Open Access Journals (Sweden)

    O. I. Rubleva

    2007-10-01

    Full Text Available The model of destruction of rocks by explosion in vertical shafts is presented. On its basis the most important parameters of technical-and-economical indices of the drilling-and-blasting technology are calculated.

  17. Multistep Optimization of Composite Drive Shaft Subject to Strength, Buckling, Vibration and Manufacturing Constraints

    Science.gov (United States)

    Cherniaev, Aleksandr; Komarov, Valeriy

    2015-10-01

    Composite drive shafts are extensively used in automotive and aeronautical applications due to lightweight combined with exceptional strength and stiffness. Complexity of the drive shaft design problem associated with the need to determine rational values for multiple parameters characterizing composite material (fiber orientation angles, stacking sequence and ply thicknesses), as well as with the fact that multiple conflicting design constraints should be considered simultaneously. In this paper we approach this problem considering carbon/epoxy drive shaft design as a multistep optimization process. It includes the following steps: 1) determination of fiber orientation angles and laminate stacking sequence based on analysis of loading conditions and analytical expressions predicting buckling load and minimal natural frequency of idealized drive shaft; 2) finding rational ply thicknesses using formal optimization procedure utilizing response surface approximations and gradient-based optimization algorithm; and 3) verification analysis of the optimized configuration with the use of nonlinear buckling analysis to ensure satisfaction of stability constraint.

  18. Different Condition Monitoring Approaches for Main Shafts of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ambühl, Simon; Sørensen, John Dalsgaard

    the applicability of different condition monitoring techniques like performance monitoring, strain gauge results and vibration analysis for crack detection on the low speed shaft. Different signal processing methods like descriptive statistics, Fourier Transforms, Wavelet transforms, Modal Assurance Criteria...

  19. Persistent knee complaints after retrograde unreamed nailing of femoral shaft fractures

    NARCIS (Netherlands)

    El Moumni, Mostafa; Schraven, Pim; ten Duis, Henk Jan; Wendt, Klaus

    2010-01-01

    Retrograde nailing is an attractive method for stabilisation of femoral shaft fractures in cases of polytrauma, ipsilateral pelvic, acetabular, tibial and femoral neck fractures, bilateral femoral fractures, obese and pregnant patients. However, retrograde nailing may result in complaints about the

  20. Follow-On Shaft Seal Evaluation for Future OMS Engine Series Valve Derivations Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Evidence of nitrogen tetroxide (NTO) and monomethylhydrazine (MMH) propellant vapor leakage across the primary and secondary shafts seals of the four OMS-E series...

  1. The process analysis and improvement of the slender and flat shaft of track recorder

    Institute of Scientific and Technical Information of China (English)

    DAI Tong-yan; WANG Wei; LIU Ying

    2006-01-01

    A slender and flat shaft is a key part of the track recorder in marine vessels. However, the axial straightness of the shaft often exceeds standard measurements after it is machined. It has also been found that its precision does not last a long time. After thorough analysis of these problems the main reasons that affect machining quality are identified-and a process modification plan is put forward that meets design requirements of the shaft. The production and practice indicate that the precision of the shaft is stable for a long period and the quality of products improved substantially after new measures were employed, securing the e accuracy of the track recording of the marine vessel.

  2. Condition monitoring of shaft of single-phase induction motor using optical sensor

    Science.gov (United States)

    Fulzele, Asmita G.; Arajpure, V. G.; Holay, P. P.; Patil, N. M.

    2012-05-01

    Transmission type of optical technique is developed to sense the condition of rotating shafts from a distance. A parallel laser beam is passed tangential over the surface of rotating shaft of a single phase induction motor and its flickering shadow is received on a photo sensor. Variations in sensor voltage output are observed on a digital storage oscilloscope. It is demonstrated that this signal carries information about shaft defects like miss alignment, play and impacts in bearings along with surface deformities. Mathematical model of signals corresponding to these shaft defects is developed. During the development and testing of the sensor, effects of reflections are investigated, sensing phenomenon is simulated, frequency response of the sensor is obtained and its performance is compared with conventional accelerometer.

  3. Coal Fields - MO 2015 Closed Non-coal Mine Shafts (SHP)

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This data set contains the locations and descriptions of abandoned non-coal mine shafts in Missouri closed by the Missouri Department of Natural Resources (DNR),...

  4. Analysis of the flexural vibration of ship's tail shaft by transfer matrix method

    Institute of Scientific and Technical Information of China (English)

    JIA Xiao-jun; FAN Shi-dong

    2008-01-01

    A ship's tail shaft has serious flexural vibration due to the cantilevered nature of the propeller's blades. Analysis of the nature frequency of flexural vibration is vital to be able to provide effective shock absorption for a ship's tail shaft. A mathematic model of tail shaft flexural vibrations was built using the transfer matrix method. The nature frequency of flexural vibration for an electrically propelled ship's tail shaft was then analyzed, and an effective method for calculating it was proposed: a genetic algorithm (GA), which calculates the nature frequency of vibration of a system. Sample calculations, with comparisons by the Prohl method under conditions bearing isotropic support, showed this method to be practical. It should have significant impact on engineering design theory.

  5. Structural dynamics studies of rotating bladed-disk assemblies coupled with flexible shaft motions

    Science.gov (United States)

    Loewy, R. G.; Khader, N.

    1983-01-01

    In order to analyze the dynamic behavior of the first stage compressor/fan of the 'E3' turbofan engine, a classical structural dynamics approach is employed to couple the motions of a flexible bladed disk to a rotating flexible shaft. The analysis accounts for flexible disk displacements which are transverse to the plane of rotation, and radial as well as tangential, and also accounts for rigid disk translations along, and rotations about, axes normal to the undeformed shaft axes. In the case of a wide range of E3 engine shaft flexibilities and speeds, some of the one-diametral node frequencies are shown to be affected by shaft degrees of freedom whose stiffness values are in general range of design practice. Coriolis forces are also found to significantly affect natural frequencies where strong coupling between certain modes is present.

  6. WIPP shaft seal system parameters recommended to support compliance calculations

    Energy Technology Data Exchange (ETDEWEB)

    Hurtado, L.D.; Knowles, M.K. [Sandia National Labs., Albuquerque, NM (United States); Kelley, V.A.; Jones, T.L.; Ogintz, J.B. [INTERA Inc., Austin, TX (United States); Pfeifle, T.W. [RE/SPEC, Inc., Rapid City, SD (United States)

    1997-12-01

    The US Department of Energy plans to dispose of transuranic waste at the Waste Isolation Pilot Plant (WIPP), which is sited in southeastern New Mexico. The WIPP disposal facility is located approximately 2,150 feet (650 m) below surface in the bedded halite of the Salado Formation. Prior to initiation of disposal activities, the Department of Energy must demonstrate that the WIPP will comply with all regulatory requirements. Applicable regulations require that contaminant releases from the WIPP remain below specified levels for a period of 10,000 years. To demonstrate that the WIPP will comply with these regulations, the Department of Energy has requested that Sandia National Laboratories develop and implement a comprehensive performance assessment of the WIPP repository for the regulatory period. This document presents the conceptual model of the shaft sealing system to be implemented in performance assessment calculations conducted in support of the Compliance Certification Application for the WIPP. The model was developed for use in repository-scale calculations and includes the seal system geometry and materials to be used in grid development as well as all parameters needed to describe the seal materials. These calculations predict the hydrologic behavior of the system. Hence conceptual model development is limited to those processes that could impact the fluid flow through the seal system.

  7. Parallel Construction Technology of Mine Shaft Sinking and Mine Shaft Headframe in 1 000m Depth Mine Shaft%千米立井井筒与井塔平行施工技术

    Institute of Scientific and Technical Information of China (English)

    赵明祥; 龙志阳; 杨永军

    2014-01-01

    In Sanxin Gold and Copper Mine ,a new mine shaft has a depth of 1 091m and a net diameter of 4.5m.A hydraulic umbrella drilling frame for rock drilling ,a central rotary grab for rock loading , 3.8m height integrated metal formwork for the shaft liner and other large mechanized matched opera-tion line were applied to the construction of the mine shaft .The new headframe of the mine main shaft is a cast-in-site reinforced concrete frame and a shear wall structure and was constructed with sliding formwork technology.The mine shaft and headframe were constructed in parallel .The total construc-tion period of the mine shaft and headframe could be reduced by seven months as predicted.Obvious economic benefit would be obtained.The technology successfully applied to the construction of the 1 000m depth mine shaft could promote the technology innovation of the mine construction sector in China ,would drive the upgrading of the integrated technology level in China mine industry and would promote the industrial technology progress.%三鑫金铜矿新主井深1091m ,净直径4.5m ,采用液压伞形钻架凿岩,中心回转式抓岩机装岩,3.8m高的整体金属大模板砌壁等大型机械化配套作业线施工。新主井井塔为现浇钢筋混凝土框架剪力墙结构,采用滑模施工工艺。井筒与井塔平行施工,预计将缩短井筒、井塔施工总工期7个月,并取得明显的经济效益。该项技术在千米立井施工中的成功应用,将促进我国建井行业技术革新,带动我国矿山产业整体技术水平的提升,推动行业技术进步。

  8. The vertical shaft construction technology of cutter head transformation of large diameter shield

    Institute of Scientific and Technical Information of China (English)

    He Feng; Wang Ying; Wang Zhenfei; Wang Baiquan

    2012-01-01

    Taking vertical shaft construction of cutter transformation of the Beijing underground diameter shield for ex- ample, the design and construction of cutter structure transformation under complex boundary conditions for large diameter shield were discussed. Practice about how to ensure the structure safety of the shaft as well as well-coordinated shield construction was explored, and reliable solutions were provided successfully, which can provide reference for similar projects.

  9. Research on torsional capacity of composite drive shaft under clockwise and counter-clockwise torque

    OpenAIRE

    Yefa Hu; Mo Yang; Jinguang Zhang; Chunsheng Song; Weiming Zhang

    2015-01-01

    The design of lay-up has a great influence on the mechanical properties of carbon fiber–reinforced plastic drive shaft. In this research, the stress states of each layer in the carbon fiber–reinforced plastic drive shaft were studied, which were different under opposite torque directions. The Tsai–Wu criterion was used to judge the torsional stability of the composite laminates. The data from finite element analysis showed that torsional capacities of a stacking sequence vary greatly with tor...

  10. On dynamic loads in parallel shaft transmissions. 1: Modelling and analysis

    Science.gov (United States)

    Lin, Edward Hsiang-Hsi; Huston, Ronald L.; Coy, John J.

    1987-01-01

    A model of a simple parallel-shaft, spur-gear transmission is presented. The model is developed to simulate dynamic loads in power transmissions. Factors affecting these loads are identified. Included are shaft stiffness, local compliance due to contact stress, load sharing, and friction. Governing differential equations are developed and a solution procedure is outlined. A parameter study of the solutions is presented in NASA TM-100181 (AVSCOM TM-87-C-3).

  11. Effect of energy distribution of laser facula on shafting aligning detection of large assembling set

    Science.gov (United States)

    Cao, Guohua; Su, Chengzhi; Xu, Hongji

    2005-01-01

    This paper introduces the principle of Shafting correction In heavy mechanical manufacturing industry, shipping industry and Nuclear industry, analyzes the effect of distribution of laser light beam spot energy to PSD measure precision. With experiment, we analyze the relation between the different distribution of laser light beam spot energy and PSD measure precision, discuss the method to compensate of shafting correction error caused by the distribution of laser light beam spot energy.

  12. Calculation Of The Brushless DC Motor Shaft Speed With Allowances For Incorrect Alignment Of Sensors

    OpenAIRE

    2015-01-01

    The paper treats of correcting calculation errors of the BLDC motor speed, based on the time elapsed between successive changes in the shaft position sensor signal. The developed method enables correction of errors of the deployment of sensors as well as rotating elements of the observation system of the motor shaft position. The correction algorithm performance was analysed with the aid of a model implemented in Matlab-Simulink environment. After confirming usefulness of the developed method...

  13. OPTIMUM CONTROL TO A PARTIALLY CONTROLLED TURBOGENERATOR SHAFT TORSIONAL VIBRATION SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The optimal control to a partially controlled turbogenerator shaft torsional vibration system is investigated. The principle of input feedforward control is presented to achieve the minimum of the average vibration energy in a system,and the optimal control matrix of the system is derived. A turbogenerator shaft system is taken as an example to simulate the optimal control process of the torsional vibration. Results from this simulation indicate that the vibration can be effectively controlled by a partial control strategy.

  14. Space Shuttle Orbital Maneuvering Subsystem (OMS) Engine Propellant Leakage Ball-Valve Shaft Seals

    Science.gov (United States)

    Lueders, Kathy; Buntain, Nick; Fries, Joseph (Technical Monitor)

    1999-01-01

    Evidence of propellant leakage across ball-valve shaft seals has been noted during the disassembly of five flight engines and one test engine at the NASA Lyndon B. Johnson Space Center, White Sands Test Facility. Based on data collected during the disassembly of these five engines, the consequences of propellant leakage across the ball-valve shaft seals can be divided into four primary areas of concern: Damage to the ball-valve pinion shafts, damage to sleeved bearings inside the ball-valve and actuator assemblies, degradation of the synthetic rubber o-rings used in the actuator assemblies, and corrosion and degradation to the interior of the actuator assemblies. The exact time at which leakage across the ball-valve shaft seals occurs has not been determined, however, the leakage most likely occurs during engine firings when, depending on the specification used, ball-valve cavity pressures range as high as 453 to 550 psia. This potential pressure range for the ball-valve cavities greatly exceeds the acceptance leakage test pressure of 332 psia. Since redesign and replacement of the ball-valve shaft seals is unlikely, the near term solution to prevent damage that occurs from shaft-seal leakage is to implement a routine overhaul and maintenance program for engines in the fleet. Recommended repair, verification, and possible preventative maintenance measures are discussed in the paper.

  15. Detection of fatigue crack on a rotating steel shaft using air-coupled nonlinear ultrasonic modulation

    Science.gov (United States)

    Song, Byeongju; Park, Byeongjin; Sohn, Hoon; Lim, Cheol-Woo; Park, Jae-Roung

    2015-04-01

    Rotating shafts in drop lifts of manufacturing facilities are susceptible to fatigue cracks as they are under repetitive heavy loading and high speed spins. However, it is challenging to use conventional contact transducers to monitor these shafts as they are continuously spinning with a high speed. In this study, a noncontact crack detection technique for a rotating shaft is proposed using air-coupled transducers (ACTs). (1) Low frequency (LF) and high frequency (HF) sinusoidal inputs are simultaneously applied to a shaft using two ACTs, respectively. A fatigue crack can provide a mechanism for nonlinear ultrasonic modulation and create spectral sidebands at the modulation frequencies, which are the sum and difference of the two input frequencies Then LF and HF inputs are independently applied to the shaft using each ACT. These three ultrasonic responses are measured using another ACT. (2) The damage index (DI) is defined as the energy of the first sideband components, which corresponding to the frequency sum and difference between HF and LF inputs. (3) Steps 1 and 2 are repeated with various combinations of HF and LF inputs. Crack existence is detected through an outlier analysis of the DIs. The effectiveness of the proposed technique is investigated using a steel shaft with a real fatigue crack.

  16. Numerically Analysed Thermal Condition of Hearth Rollers with the Water-Cooled Shaft

    Directory of Open Access Journals (Sweden)

    A. V. Ivanov

    2016-01-01

    Full Text Available Continuous furnaces with roller hearth have wide application in the steel industry. Typically, furnaces with roller hearth belong to the class of medium-temperature heat treatment furnaces, but can be used to heat the billets for rolling. In this case, the furnaces belong to the class of high temperature heating furnaces, and their efficiency depends significantly on the reliability of the roller hearth furnace. In the high temperature heating furnaces are used three types of watercooled shaft rollers, namely rollers without insulation, rollers with insulating screens placed between the barrel and the shaft, and rollers with bulk insulation. The definition of the operating conditions of rollers with water-cooled shaft greatly facilitates the choice of their design parameters when designing. In this regard, at the design stage of the furnace with roller hearth, it is important to have information about the temperature distribution in the body of the rollers at various operating conditions. The article presents the research results of the temperature field of the hearth rollers of metallurgical heating furnaces. Modeling of stationary heat exchange between the oven atmosphere and a surface of rollers, and between the cooling water and shaft was executed by finite elements method. Temperature fields in the water-cooled shaft rollers of various designs are explored. The water-cooled shaft rollers without isolation, rollers with screen and rollers with bulk insulation, placed between the barrel and the water-cooled shaft were investigated. Determined the change of the thermo-physic parameters of the coolant, the temperature change of water when flowing in a pipe and shaft, as well as the desired pressure to supply water with a specified flow rate. Heat transfer coefficients between the cooling water and the shaft were determined directly during the solution based on the specified boundary conditions. Found that the greatest heat losses occur in the

  17. A Survey of Serious Aircraft Accidents Involving Fatigue Fracture. Volume 2. Rotary-Wing Aircraft (Etude sur des Accidents Importants d’Avions du aux Effets des Fractures de Fatigue. Volume 2. Effets sur des Helicopteres).

    Science.gov (United States)

    1983-04-01

    Cal. USA. 12B Tail rotor drive shaft assembly (centering pin of cardan joint). NTSB file 3-2188. P11 Bell 25 Jun 68 0 S Boron, Cal. USA. 47G-3B-1 Tail...Canada. UH-12E Tail rotor pinion gear. PIO Hiller 12B 27 May 68 0 S Arroyo Grande, Cal. USA. Tail rotor drive shaft assembly (centering pin of cardan

  18. A Nonlinear Dynamic Finite Element Analysis of Drilling Shaft including Multispan Auxiliary Supports in Deep-Hole Machining

    Directory of Open Access Journals (Sweden)

    L. F. Kong

    2013-01-01

    Full Text Available This paper presents a method to enhance computational efficiency of the nonlinear dynamic analysis of the large-scale deep-hole drilling machine. Based on finite element model, the drilling shaft system is constructed into Timoshenko beam element on the basis of flexible rotary shaft so as to increase the accuracy of numerical calculation. In order to save the calculation time and resources, modal synthesis technique is adopted to reduce the feature modal of linear freedom degrees of drilling shaft system. As a result, the accuracy required by the non-linear analysis will not be loss. On the basis of these, the whirling characteristics of drilling shaft system are studied under the conditions of different shaft lengths, and simultaneously, the stability patterns of drilling shaft motion and its stability region are obtained in the selected drilling depth and cutting speed parameters while drilling intersection holes.

  19. Geologic mapping of the air intake shaft at the Waste Isolation Pilot Plant

    Energy Technology Data Exchange (ETDEWEB)

    Holt, R.M.; Powers, D.W. (IT Corporation (USA))

    1990-12-01

    The air intake shaft (AS) was geologically mapped from the surface to the Waste Isolation Pilot Plant (WIPP) facility horizon. The entire shaft section including the Mescalero Caliche, Gatuna Formation, Santa Rosa Formation, Dewey Lake Redbeds, Rustler Formation, and Salado Formation was geologically described. The air intake shaft (AS) at the Waste Isolation Pilot Plant (WIPP) site was constructed to provide a pathway for fresh air into the underground repository and maintain the desired pressure balances for proper underground ventilation. It was up-reamed to minimize construction-related damage to the wall rock. The upper portion of the shaft was lined with slip-formed concrete, while the lower part of the shaft, from approximately 903 ft below top of concrete at the surface, was unlined. As part of WIPP site characterization activities, the AS was geologically mapped. The shaft construction method, up-reaming, created a nearly ideal surface for geologic description. Small-scale textures usually best seen on slabbed core were easily distinguished on the shaft wall, while larger scale textures not generally revealed in core were well displayed. During the mapping, newly recognized textures were interpreted in order to refine depositional and post-depositional models of the units mapped. The objectives of the geologic mapping were to: (1) provide confirmation and documentation of strata overlying the WIPP facility horizon; (2) provide detailed information of the geologic conditions in strata critical to repository sealing and operations; (3) provide technical basis for field adjustments and modification of key and aquifer seal design, based upon the observed geology; (4) provide geological data for the selection of instrument borehole locations; (5) and characterize the geology at geomechanical instrument locations to assist in data interpretation. 40 refs., 27 figs., 1 tab.

  20. Torsional Behaviour and Finite Element Analysis of the Hybrid Laminated Composite Shafts: Comparison of VARTM with Vacuum Bagging Manufacturing Method

    OpenAIRE

    Mehmet Emin Taşdelen; Mehmet Halidun Keleştemur; Ercan Şevkat

    2016-01-01

    Braided sleeve composite shafts are produced and their torsional behavior is investigated. The braided sleeves are slid over an Al tube to create very strong and rigid tubular form shafts and they are in the form of 2/2 twill biaxial fiber fabric that has been woven into a continuous sleeve. Carbon and glass fibers braided sleeves are used for the fabrication of the composite shafts. VARTM (vacuum assisted resin transfer molding) and Vacuum Bagging are the two different types of manufacturing...

  1. Elementary Introduction of Shaft Alignment Calculation and the Application of Nauticus Shaft Alignment Software%浅谈轴系校中计算及Nauticus Shaft Alignment软件的应用

    Institute of Scientific and Technical Information of China (English)

    汤瑾璟

    2009-01-01

    本文以介绍轴系校中的计算方法为主,同时简单介绍Nauticus Shaft Alignment软件在计算过程中的应用.轴系校中的目的在于通过调整各轴承的合理位置,使各个轴承上的负荷在各种工况下均能合理分配.

  2. Influence of Bearing Stiffness on the Nonlinear Dynamics of a Shaft-Final Drive System

    Directory of Open Access Journals (Sweden)

    Xu Jinli

    2016-01-01

    Full Text Available The bearing stiffness has a considerable influence on the nonlinear coupling vibration characteristics of the shaft-final drive system. A 14-DOF nonlinear coupled vibration model was established by employing the lumped mass method so as to identify the coupling effects of the bearing stiffness to the vibration response of the shaft-final drive system. The engine’s torque ripple, the alternating load from the universal joint (U-joint, and the time-varying mesh parameters of hypoid gear of the shaft-final drive system were also considered for accurate quantitative analysis. The numerical analysis of the vibration response of the coupled system was performed and the experimental measurements were carried out for the validation test. Results show that, at the given driving speed, improving the bearing stiffness can reduce the vibration response of the given coupled system; however, when the bearing stiffness increases to a critical value, the effects of bearing stiffness on the vibration reduction become insignificant; when the driving speed changes, the resonance regions of the coupled system vary with the bearing stiffness. The results are helpful to determine the proper bearing stiffness and the optimum control strategy for the shaft-final drive system. It is hoped that the optimal shaft-final drive system can provide good vibration characteristics to achieve the energy saving and noise reduction for the vehicle application.

  3. Hoffa fracture associated with ipsilateral femoral shaft fracture: clinical feature and treatment.

    Science.gov (United States)

    Gong, Yu-Bao; Li, Qing-Song; Yang, Chen; Li, Shu-Qiang; Liu, Jian-Guo; Qi, Xin

    2011-01-01

    Hoffa fracture associated with ipsilateral femoral shaft fracture is very rare. Three cases of this rare type of injury were retrospectively reviewed. The sites of femoral shaft fractures and Hoffa fractures were documented. All femoral shaft fractures were managed with internal fixation. The rate of misdiagnosis for the Hoffa fractures was documented. Functions of the affected knees were evaluated according to the modified Hospital for Special Surgery (HSS) scores at two years follow-up. Femoral fractures were either transverse or composite in all three cases. Ipsilateral Hoffa fractures occurred at medial condyle in two cases, and lateral condyle in one case. Only one Hoffa fracture was identified preoperatively. All the femoral shaft fractures healed uneventfully. In the patient whose Hoffa fracture was correctly diagnosed, the modified HSS score was 94. In another patient, whose Hoffa fracture was treated by a second operation, the modified HSS score was 93. And in the third case, who refused additional operation for the Hoffa fracture, the modified HSS score was only 70. Conclusively femoral shaft fracture can be associated with ipsilateral Hoffa fracture, especially in motorcycle accident. This type of injury is very rare and misdiagnosis is common.

  4. Injuries Associated with Femoral Shaft Fractures with Special Emphasis on Occult Injuries

    Directory of Open Access Journals (Sweden)

    E Carlos Rodriguez-Merchan

    2013-12-01

    Full Text Available Background: Fractures of the femoral shaft are mostly the result of high-energy accidents that also cause multiple trauma injuries, in particular ipsilateral knee and hip injuries. The purpose of this study was to investigate the incidence of injuries associated with femoral shaft fractures and how many of them were undetected. Methods: We studied 148 patients (150 femoral shaft fractures with an average age of 52 (range: 18-97. Femoral shaft fractures were treated with antegrade intramedullary nailing in 118 cases (78.7%, and with open reduction and internal fixation in 32 cases (21.3%. Unlocked reamed intramedullary nailing was performed in Winquist type I and type II fractures, while statically locked unreamed intramedullary nailing was carried out in Winquist type III and type IV fractures. Results: There were 70 patients with associated injuries (46.4%. The associated injuries went undetected in 18 out of 70 patients (25.5%. Six femoral nonunions (4% occurred in patients under 70 years of age (high-energy accidents treated by open reduction and internal fixation. Conclusion: Injuries associated with femoral shaft fractures were very frequent (46.4% in our series, with 25.5% undetected. Open reduction and internal fixation was a poor prognostic factor of nonunion in these fractures.

  5. Interlocking nailing of humeral shaft fractures a retrospective study of 114 patients

    Directory of Open Access Journals (Sweden)

    Demirel M

    2005-10-01

    Full Text Available Background: Fractures of the humeral shaft are relatively common injuries. Literature suggests that humeral shaft fractures represent approximately 3 % of all fractures. There are several modalities for the management of diaphyseal humeral fractures. The latest investigations emphasize the concept of minimal exposure and rigid fixation. Aim: The aim of the study is to evaluate the results of antegrade intramedullary nailing in humeral shaft fractures. Design: A retrospective review Settings: Patients were treated in private hospital settings by 3 orthopaedics surgeon Material and Methods: Between 1995 and 2003, the technique of antegrade locked intramedullary nailing with UHN in humeral shaft fractures was performed on 114 patients. Forty-two (36% patients sustained multiple traumas, and 22 (19% fractures were open. The outcomes were evaluated with a mean follow-up of 41 months. Statistical analysis used: Ranges of results given Results:0 In 109 fractures primary union observed. In the other five patients union achieved after removal of the nail and fixation with DCP and bone grafting. The average time for union was 13 weeks (range, 10-36 weeks. One hundred-five patients had excellent or satisfactory recovery of shoulder and elbow function. Complications included impingement due to proximal locking screws in two patients and prominent nail in three patients, transient postoperative radial nerve palsy in four patients. Conclusions: This study shows that antegrade locked nailing in humeral shaft fractures are reliable and also effective in multiply injured patients.

  6. DESIGN AND ANALYSIS OF NOVEL ACTIVE ACTUATOR TO CONTROL LOW FREQUENCY VIBRATIONS OF SHAFT SYSTEM

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Aiming at providing with high-load capability in active vibration control of large-scale rotor system, a new type of active actuator to simultaneously reduce the dangers of low frequency flexural and torsional vibrations is designed. The actuator employs electro-hydraulic system and can provide a high and circumferential load. To initialize new research, the characteristics of various kinds of active actuators to control rotor shaft vibration are briefly introduced. The purpose of this paper is to introduce the preliminary results via presenting the structure, functions and operating principles, in particular, the working process of the electro-hydraulic system of the new actuator which includes a set of high speed electromagnetic valves and a series of sloping cone-shaped openings, and presenting the transmission relationships among the control parameters from control signals into the valves to active load onto shaft. The course of the work is dynamic, and a series of spatial forces and moments are put on the shaft to get an external resultant force to reduce excitations that induce vibration of shafts. By checking states of vibration, the actuator can control the impulse width and the interval of injection time for applying different control force to a vibration shaft in two circumference directions through the regulating action of a set of combination directional control valves. The results from simulating analysis and experiment show evidence of that this design can satisfy the case of active process of decreasing of flexural and torsional vibrations.

  7. The Effects of Chromium Concentration on Heat-Treated Magnetoelastic Torque Transducer Shafts

    Science.gov (United States)

    Orris, Jason; Wilson, Jason; Jurs, Chris; Boley, Mark

    2003-03-01

    In many applications where a sensory transducer ring would be impractical, a hollow ferromagnetic high-speed steel "shaft type" torque sensor can be constructed. This requires the creation of two distinct portions of the shaft in which a high degree of oppositely polarized circumferential magnetization can be maintained with a saturated alignment of the magnetic domains due to the high circumferential coercive force in the material. In a related work, we have found that increasing nickel concentrations improve transducer sensitivities (field signal per applied torque) but also cause the shafts to become too brittle for most torque transfer applications. In this work, we have discovered that a similar or even larger improvement in transducer sensitivity can be gained by increasing the chromium concentration (with nickel concentrations under 0.30 its mechanical properties. The three steel shafts we investigated had respective chromium concentrations of 0.15S-7, and D-2. Their transducer sensitivities were found as 1.5, 4.0, and 12.5 mG/N-m, respectively, while the latter two steel shafts also exhibited still further increases in their sensitivity following their standard heat treatments. The area of the axial hysteresis curves for these three steels was also found to dramatically decrease as the chromium concentration and the transducer sensitivity increased, while relatively little change was observed in the already broad circumferential hysteresis curves.

  8. Percutaneous Kirschner wire (K-wire fixation for humerus shaft fractures in children: A treatment concept

    Directory of Open Access Journals (Sweden)

    Ramji Lal Sahu

    2013-01-01

    Full Text Available Background: Fractures of the humeral shaft are uncommon, representing less than 10 percent of all fractures in children. Humeral shaft fractures in children can be treated by immobilisation alone. A small number of fractures are unable to be reduced adequately or maintained in adequate alignment, and these should be treated surgically. In the present study, Kirschner wires (K-wire were used to achieve a closed intramedullary fixation of humeral shaft fractures. The objective of this study was to evaluate the efficacy of intramedullary K-wires for the treatment of humeral shaft fracture in children. Patients and Methods: This prospective study was conducted in the Department of Orthopaedic surgery in M. M. Medical College from June 2005 to June 2010. Sixty-eight children with a mean age of 7.7 years (range, 2-14 years were recruited from Emergency and out patient department having closed fracture of humerus shaft. All patients were operated under general anaesthesia. All patients were followed for 12 months. Results: Out of 68 patients, 64 patients underwent union in 42-70 days with a mean of 56 days. Complications found in four patients who had insignificant delayed union which were united next 3 weeks. Intramedullary K-wires were removed after an average of 5 months without any complications. The results were excellent in 94.11% and good in 5% children. Conclusion: This technique is simple, quick to perform, safe and reliable and avoids prolonged hospitalization with good results and is economical.

  9. Hoffa fracture associated with ipsilateral femoral shaft fracture: clinical feature and treatment

    Institute of Scientific and Technical Information of China (English)

    GONG Yu-bao; LI Qing-song; YANG Chen; LI Shu-qiang; LIU Jian-guo; QI Xin

    2011-01-01

    Hoffa fracture associated with ipsilateral femoral shaft fracture is very rare.Three cases of this rare type of injury were retrospectively reviewed.The sites of femoral shaft fractures and Hoffa fractures were documented.All femoral shaft fractures were managed with internal fixation.The rate of misdiagnosis for the Hoffa fractures was documented.Functions of the affected knees were evaluated according to the modified Hospital for Special Surgery (HSS) scores at two years follow-up.Femoral fractures were either transverse or composite in all three cases.Ipsilateral Hoffa fractures occurred at medial condyle in two cases,and lateral condyle in one case.Only one Hoffa fracture was identified preoperatively.All the femoral shaft fractures healed uneventfully.In the patient whose Hoffa fracture was correctly diagnosed,the modified HSS score was 94.In another patient,whose Hoffa fracture was treated by a second operation,the modified HSS score was 93.And in the third case,who refused additional operation for the Hoffa fracture,the modified HSS score was only 70.Conclusively femoral shaft fracture can be associated with ipsilateral Hoffa fracture,especially in motorcycle accident.This type of injury is very rare and misdiagnosis is common.

  10. Minimization of shaft oscillations by fuzzy controlled SMES considering time delay

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Mohd Hasan; Dougal, Roger A. [Department of Electrical Engineering, University of South Carolina, 301 South Main Street, Columbia, SC 29208 (United States); Wu, Bin [Department of Electrical and Computer Engineering, Ryerson University, George Vari Engineering and Computing Center, 245 Church Street, Toronto, Ontario M5B 1Z2 (Canada); Tamura, Junji [Department of Electrical and Electronic Engineering, Kitami Institute of Technology, 165 Koen cho, Kitami, Hokkaido 090-8507 (Japan)

    2010-07-15

    This paper analyzes the effect of fuzzy logic-controlled superconductive magnetic energy storage (SMES) on minimizing shaft torsional oscillations of synchronous generators in a multi-machine power system. The proposed fuzzy logic controller has been designed in a very simple way considering only one input variable and one output variable. The time derivative of the total kinetic energy deviation (TKED) of the synchronous generators is used as the global input to the fuzzy controller for SMES switching. The influence of time delay associated with the global input calculation of the fuzzy controller on minimizing shaft torsional oscillations is investigated. Global positioning system (GPS) is proposed for the practical implementation of the calculation of the global input to the fuzzy controller. Simulation results of a balanced fault at different points in a multi-machine power system show that the proposed SMES can minimize the shaft torsional oscillations of synchronous generators well. Moreover, the time delay has an influence on the performance of fuzzy controlled SMES to minimize shaft torsional oscillations. However, even though the performance of fuzzy controlled SMES is somewhat effected by the communication delay, it is clear from the simulation responses that the fuzzy logic-controlled SMES considering typical communication delays can minimize the shaft torsional oscillations of synchronous generators well. (author)

  11. 基于有限元法轴段偏中时轴系校中状态的研究%Research on shafting alignment as shaft segment is misalignment based on finite element method

    Institute of Scientific and Technical Information of China (English)

    常宁; 刘正林; 魏颖春

    2011-01-01

    依据船舶轴系直线校中原理,介绍了ANSYS环境中轴系校中建模的方法和参数的设置,并在ANSYS环境中建立了轴系校中计算的有限元模型.简述了轴系直线校中法,详细说明了轴段偏中时轴系校中的状态,得出了轴段校中时轴承负荷、轴系挠度、轴系转角、轴系剪力等参数,并与轴系偏中时轴承负荷、轴系挠度、轴系转角、轴系剪力等参数做比较,得到了轴系校中参数变化规律,同时计算得出了轴段偏中产生的附加负荷对轴系校中的影响,为船舶轴系校中设计及检修提供了依据.%According to principles of straight alignment of shafting the method for modeling in the ANSYS environment and the method for setting parameters are introduced as well as FEM model for calculating in shafting alignment is established in the ANSYS environment.Then the method for straight alignment of shafting is outlined,in which shafting alignment during the shaft segment misaligning is specified.Thus parameters during the misalignment such as bearing load, shafting deflection, shafting corners ,shafting shearing force is acquired After comparing with the above parameters,the parameter variation law is obtained.At the same time, the influence of additional load occurred in the shaft segment misalignment to alignment of shafting is acquired,which provides a basis for the design and maintenance of ship shafting alignment.

  12. 东风4D型货运内燃机车万向轴惯性断裂的原因分析及预防措施%Cause Analysis and Improvement on the Frequent Rupture Failure of the Cardan Shaft of the DF4D Type Freight Diesel Locomotive

    Institute of Scientific and Technical Information of China (English)

    叶岚

    2003-01-01

    阐述了东风4D型货运机车万向轴断裂的规律,进行了原因分析,介绍了万向轴断裂事故处理的实例,并对同台柴油机上各喷油泵小油量相差大易引起的其它后果进行了分析,最后提出了具体的预防措施及操作程序.

  13. Causes and prevention of looseness of connecting bolts for cardan shaft flanges of DF7 type locomotive%DF7型机车万向轴法兰联接螺栓松动的原因及防止

    Institute of Scientific and Technical Information of China (English)

    苏永军

    2002-01-01

    @@ DF7型机车具有功率大、牵引性能好的特点,应用于大型编组站和重载列车调车作业.在厂修试验过程中,机车工况转换频繁,柴油机转速升、降幅度较大,使辅助传动系统承受较大的冲击载荷,致使该系统的故障增加.从机车的运用和日常检修情况分析,万向轴法兰联接螺栓松动是DF7型机车辅助传动系统的惯性故障.

  14. Bending Distortion Analysis of a Steel Shaft Manufacturing Chain from Cold Drawing to Grinding

    Science.gov (United States)

    Dias, Vinicius Waechter; da Silva Rocha, Alexandre; Zottis, Juliana; Dong, Juan; Epp, Jérémy; Zoch, Hans Werner

    2017-04-01

    Shafts are usually manufactured from bars that are cold drawn, cut machined, induction hardened, straightened, and finally ground. The main distortion is characterized by bending that appears after induction hardening and is corrected by straightening and/or grinding. In this work, the consequence of the variation of manufacturing parameters on the distortion was analyzed for a complete manufacturing route for production of induction hardened shafts made of Grade 1045 steel. A DoE plan was implemented varying the drawing angle, cutting method, induction hardening layer depth, and grinding penetration depth. The distortion was determined by calculating curvature vectors from dimensional analysis by 3D coordinate measurements. Optical microscopy, microhardness testing, residual stress analysis, and FEM process simulation were used to evaluate and understand effects of the main carriers of distortion potential. The drawing process was identified as the most significant influence on the final distortion of the shafts.

  15. OPTIMIZATION OF PLY STACKING SEQUENCE OF COMPOSITE DRIVE SHAFT USING PARTICLE SWARM ALGORITHM

    Directory of Open Access Journals (Sweden)

    CHANNAKESHAVA K. R.

    2011-06-01

    Full Text Available In this paper an attempt has been made to optimize ply stacking sequence of single piece E-Glass/Epoxy and Boron /Epoxy composite drive shafts using Particle swarm algorithm (PSA. PSA is a population based evolutionary stochastic optimization technique which is a resent heuristic search method, where mechanics are inspired by swarming or collaborative behavior of biological population. PSA programme is developed to optimize the ply stacking sequence with an objective of weight minimization by considering design constraints as torque transmission capacity, fundamental natural frequency, lateral vibration and torsional buckling strength having number of laminates, ply thickness and stacking sequence as design variables. The weight savings of the E-Glass/epoxy and Boron /Epoxy shaft from PAS were 51% and 85 % of the steel shaft respectively. The optimum results of PSA obtained are compared with results of genetic algorithm (GA results and found that PSA yields better results than GA.

  16. 1/2 SUBHARMONIC RESONANCE OF A SHAFT WITH UNSYMMETRICAL STIFFNESS

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    The 1/2 subharmonic resonance of a shaft with unsymmetrical stiffness is studied. By means of the Hamilton's principle the nonlinear differential equations of motion of the rotating shaft are derived in the rotating rectangular coordinate system. Transforming the equations of motion from rotating coordinate system into stationary coordinate system and introducing a complex variable, the equation of motion in complex variable form is obtained, in which the stiffness coefficient varies periodically with time. It presents a nonlinear oscillation system under parametric excitation. By applying the method of multiple scales (MMS) the averaged equation, the bifurcating response equations and local bifurcating set are obtained. Via the theory of singularity, the stability of constant solutions is analyzed and bifurcating response curves are obtained. This study shows that the rotating shaft has rich bifurcation phenomena.

  17. Fatigue life on a full scale test rig: Forged versus cast wind turbine rotor shafts

    Science.gov (United States)

    Herrmann, J.; Rauert, T.; Dalhoff, P.; Sander, M.

    2016-09-01

    To reduce uncertainties associated with the fatigue life of the highly safety relevant rotor shaft and also to review today's design practice, the fatigue behaviour will be tested on a full scale test rig. Until now tests on full scale wind turbine parts are not common. Therefore, a general lack of experience on how to perform accelerated life time tests for those components exists. To clarify how to transfer real conditions to the test environment, the arrangements and deviations for the upcoming experimental test are discussed in detail. In order to complete investigations of weight saving potentials, next to getting a better comprehension of the fatigue behaviour by executing a full scale test, a further outcome are suggestions for the usage of cast and forged materials regarding the fatigue and the remaining life of the rotor shaft. It is shown, that it is worthwhile to think about a material exchange for the forged rotor shaft.

  18. A STUDY OF CLOSED INTERLOCKING NAILING FOR FRACTURES OF SHAFT OF FEMUR IN ADULTS

    Directory of Open Access Journals (Sweden)

    Ashwin

    2013-06-01

    Full Text Available ABSTRACT: BACKGROUND:-This study is to determine the clinical course and results after interlocking nailing for femoral shaft fractures , merits and demerits of interlocking nailing, achieving the final goals of femoral shaft fracture management with special references to time for radiological union, knee stiffness, limb length discrepancy, ambulation and return to work. Femur is the strongest and heaviest bone in the human skeleton. It is also the longest bone contributing 26% to height of an individual. Fractures of the shaft of the femur are among the most common fractures encountered in orthopaedic practice, can cause prolong morbidity and extensive disability unless treatment is appropriate. Many treatment modalities were described; with many surgeons advocating different methods of treatment .At present Interlocking nailing of the femur seems to be the ideal method of treatment for complex femoral fractures.

  19. Development of the laser alignment system with PSD used for shaft calibration

    Science.gov (United States)

    Jiao, Guohua; Li, Yulin; Hu, Baowen

    2006-02-01

    Shaft calibration is an important technique during installation and maintenance of a rotating machine. It requires unique and high-precision measurement instruments with calculation capability, and relies on experience on heavy, high-speed, or high-temperature machines. A high-precision laser alignment system has been designed using PSD (Position Sensing Detector) to change traditional manual way of shaft calibration and to make the measurement easier and more accurate. The system is comprised of two small measuring units (Laser transmitter and detector) and a hand operated control unit or a PC. Such a laser alignment system has been used in some actual shaft alignment with offset resolution 1.5μm and angular resolution 0.1°.

  20. Comparison of Solid and Hollow Torque Transducer Shaft Response in a High Alloy Stainless Steel

    Science.gov (United States)

    Milby, Christopher L.; Hecox, Bryan G.; Wiewel, Joseph L.; Boley, Mark S.

    2007-03-01

    Recent investigations of the torque transducer response function (ambient field signal versus applied torque or shear stress) have been conducted in a 13% chromium and 8% nickel stainless steel alloy in both the hollow shaft and solid shaft configuration. An understanding of both is needed for applications with differing yield strength and hardness requirements. Axial hysteresis measurements conducted before and after heat treatment exhibited little difference in coercivity and retentivity between the two sample types. However, the field mapping and transducer sensitivity studies showed the hollow shaft configuration to have a far superior degree of polarization in the sensory region and to exhibit an enhanced sensitivity, especially after heat treatment. This is most likely due to its more efficient provision of closed circumferential geometry for the field lines and improved grain alignment during heat treatment.

  1. latrogenic brachial artery injury during anterolateral plating of humeral shaft fracture

    Institute of Scientific and Technical Information of China (English)

    Vishal Kumar; Prateek Behera; Sameer Aggarwal; Umesh Kumar Meena

    2013-01-01

    There are several well defined indications for surgical management of humeral shaft fractures.Operative procedures on the humerus are associated with their own complications.Iatrogenic brachial artery injury as a complication of humeral shaft plating has not been reported previously.We report a case of a 48 years old femalewho received operation at a district hospital and was referred to us when the surgeon could not palpate the pulse.CT angiogram showed that there was segmental non-opacification of the brachial artery.There was distal reformation and the thrombosis was decided to be managed conservatively.We believe that the arterial injury was a result ofimproper surgical technique and the segmental block might be due to improper use of plate holding forceps.This case report makes us aware of a rare complication of operative management of humeral shaft fractures and that basic principles of surgery must be always followed to prevent such injuries.

  2. Humeral shaft fracture treatment in the elite throwing athlete: a unique application of flexible intramedullary nailing.

    Science.gov (United States)

    Lee, Christopher S; Davis, Shane M; Ho, Hoang-Anh; Fronek, Jan

    2013-01-01

    Humeral shaft stress fractures are being increasingly recognized as injuries that can significantly impact throwing mechanics if residual malalignment exists. While minimally displaced and angulated injuries are treated nonoperatively in a fracture brace, the management of significantly displaced humeral shaft fractures in the throwing athlete is less clear. Currently described techniques such as open reduction and internal fixation with plate osteosynthesis and rigid antegrade/retrograde locked intramedullary nailing have significant morbidity due to soft tissue dissection and damage. We present a case report of a high-level baseball pitcher whose significantly displaced humeral shaft stress fracture failed to be nonoperatively managed and was subsequently treated successfully with unlocked, retrograde flexible intramedullary nailing. The athlete was able to return to pitching baseball in one year and is currently pitching in Major League Baseball. We were able to recently collect 10-year follow-up data.

  3. A study of the influence of bearing clearance on lateral coupled shaft/disk rotordynamics

    Science.gov (United States)

    Flowers, George T.; Wu, Fang S.

    1992-06-01

    This study examines the influence of bearing clearance on the dynamical behavior of a rotating, flexible disk/shaft system. Most previous work in nonlinear rotordynamics has tended to concentrate separately on shaft vibration or on bladed disk vibration, neglecting the coupling dynamics between them. The current work examines the important rotordynamical behavior of coupled disk/shaft dynamics. A simplified nonlinear model is developed for lateral vibration of a rotor system with a bearing clearance nonlinearity. The steady-state dynamical behavior of this system is explored using numerical simulation and limit cycle analysis. It is demonstrated that bearing clearance effects can produce superharmonic vibration that may serve to excite high amplitude disk vibration. Such vibration could lead to significantly increased bearing loads and catastrophic failure of blades and disks. In addition, multi-valued responses and aperiodic behavior was observed.

  4. APPLICATION OF ELECTRONIC TACHEOMETER FOR PREAND POST-CONSTRUCTION SURVEY OF ELEVATOR SHAFT

    Directory of Open Access Journals (Sweden)

    M. S. Nesterionok

    2015-01-01

    Full Text Available Floor-by-floor survey of installed elements of an elevator shaft using coordinate method and tacheometer is also inhibited by the necessity to determine device installation points for floors of every mounting horizon that leads to additional measurements due to conditions of the completed building framework and presence of a great number of situational disturbances and then it entails significant time expenditure and diminution of accuracy in the obtained results. Technical capabilities of the modern electronic tacheometer substantially simplify an accomplishment of the mission because the device can be applied not only in function of vertical projection but it can be used for preand post-construction survey of the elevator shaft with the help of advanced radiation method. While using the given method the electronic tacheometer equipped with diagonal ocular is installed over a bearing sign in the elevator pit and control points of the elevator shaft are determined with the help of specially developed portable beam deflector in the form of disc with radius r, which is fixed to a handle rod and orientated perpendicularly to a laser beam. An innovation diagram for preand post-construction survey of elevator shaft has been developed while applying this type of deflector. The diagram is characterized by high efficiency due to the fact that one tacheometer installation makes it possible to execute highly accurate, complete plane and high-level surveying of the whole elevator shaft including doorways, door sills and jambs.The paper proposes a new method for pre and post construction survey of the elevator shaft using the electronic tacheometer while applying specially developed beam deflector that ensures a geometric fixing of one or simultaneously two surveying points to spatial coordinate system where the preand post-construction survey is carried out. The method is characterized by high geometric accuracy and technological efficiency.

  5. Vibration and Stability of Variable Cross Section Thin-Walled Composite Shafts with Transverse Shear

    Directory of Open Access Journals (Sweden)

    Ma Jing-min

    2015-01-01

    Full Text Available A dynamic model of composite shaft with variable cross section is presented. Free vibration equations of the variable cross section thin-walled composite shaft considering the effect of shear deformation are established based on a refined variational asymptotic method and Hamilton’s principle. The numerical results calculated by Galerkin method are analyzed to indicate the effects of ply angle, taper ratio, and transverse shear deformation on the first natural frequency and critical rotating speed. The results are compared with those obtained by using finite element package ANSYS and available in the literature using other models.

  6. Fuzzy Reliability Design for the Interference Articulation of a Roller Shaft

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    With regard to function, the strengths for interference articulation of a roller shaft formed a series system. As the three strength reliabilities conditioned each other, there was a problem for the system reliability to apportion rationally. In fact, there was a transition from safety to deactivation. The state of structure was fuzziness which was in both safety and non-safety states. Therefore the reliability was a fuzzy event which considered the randomness for some design parameters and the fuzziness for the thresholds between generalized strength safety and deactivation. The mathematical model of fuzzy reliability design for the interference articulation of the roller shaft was presented. Eight design examples were calculated. ``

  7. Atypical bisphosphonate-associated subtrochanteric and femoral shaft stress fractures: diagnostic features on bone scan.

    Science.gov (United States)

    Probst, Stephan; Rakheja, Rajan; Stern, Jerry

    2013-05-01

    A 69-year-old woman presented with a spontaneous right subtrochanteric hip fracture. Pan-imaging following orthopedic repair failed to identify a primary malignancy to explain the presumed pathologic basis for this fracture. The patient then underwent bone scintigraphy and SPECT/CT which showed mild uptake in multifocal endosteal thickening of the lateral left femoral diaphysis, diagnostic of bisphosphonate-associated femoral shaft stress fractures, but no evidence of metastatic bone disease. Atypical bisphosphonate-associated subtrochanteric and femoral shaft stress fractures have a fairly specific appearance on bone scintigraphy, and nuclear medicine physicians should be aware of this relatively infrequent emerging pathology.

  8. Different Condition Monitoring Approaches for Main Shafts of Offshore Wind Turbines

    DEFF Research Database (Denmark)

    Ambühl, Simon; Sørensen, John Dalsgaard

    Condition monitoring can be used to detect faults and failures at an early stage. Thus it decreases the overall maintenance expenses. This report gives an example of condition monitoring with focus on early crack detection in the main shaft of an offshore wind turbine. This article discusses...... the applicability of different condition monitoring techniques like performance monitoring, strain gauge results and vibration analysis for crack detection on the low speed shaft. Different signal processing methods like descriptive statistics, Fourier Transforms, Wavelet transforms, Modal Assurance Criteria...

  9. Analysis of Indicator Diagrams of a Water Injected Twin-shaft Screw-type Expander

    OpenAIRE

    Nikolov, Alexander; Brümmer, Andreas

    2016-01-01

    Twin-shaft screw-type expanders offer a high potential for energy conversion in the lower and medium power range, for instance as expansion engines in Rankine cycles for exhaust heat recovery. With regard to minimizing internal leakages and lubricating moving machine parts, an auxiliary liquid or liquid working fluid can be fed to the screw expander. In this paper, indicator diagrams of a twin-shaft screw-type expander prototype designed at the Chair of Fluidics at TU Dortmund University are ...

  10. Method of Weave Design Using the Concept of Auxiliary Dobby Shaft

    Institute of Scientific and Technical Information of China (English)

    LU Jia-liang; XU Zheng

    2010-01-01

    The craft of auxiliary dobby shaft is one of methods used in the traditional figured woven textiles and especially brocade in China.Based on the principle of auxiliary dobby shaft,a new method of weave design was proposed.The relevant arrangement of warp and weave design were discussed.It is shown that this method can be applied on one electronic jacquard loom with single warp beam for new product development and production.And this effect will open up a new way to reproduce traditional fabrics in order to protect and develop Chinese traditional culture.

  11. Calculation Of The Brushless DC Motor Shaft Speed With Allowances For Incorrect Alignment Of Sensors

    Directory of Open Access Journals (Sweden)

    Kolano Krzysztof

    2015-09-01

    Full Text Available The paper treats of correcting calculation errors of the BLDC motor speed, based on the time elapsed between successive changes in the shaft position sensor signal. The developed method enables correction of errors of the deployment of sensors as well as rotating elements of the observation system of the motor shaft position. The correction algorithm performance was analysed with the aid of a model implemented in Matlab-Simulink environment. After confirming usefulness of the developed method through simulation, its usefulness was verified in real closed-loop feedback systems with a BLDC motor. The results of measurements carried out at the developed laboratory station are presented.

  12. Three-dimensional measurement of femoral neck anteversion and neck shaft angle.

    Science.gov (United States)

    Sangeux, Morgan; Pascoe, Jessica; Graham, H Kerr; Ramanauskas, Fiona; Cain, Tim

    2015-01-01

    We present a three-dimensional measurement technique for femoral neck anteversion and neck shaft angles which do not require alignment of the femoral and scanner axes. Two assessors performed the measurements on 11 patients (22 femurs). Repeatability between assessors was 2.7 degrees for femoral neck anteversion and 4.8 degrees for neck shaft angle. Measurements compared with an alternative single slice method were different by 2 degrees (3 degrees) in average. The method was repeatable and appropriate for clinical practice.

  13. Study on flaw identification of ultrasonic signal for large shafts based on optimal support vector machine

    Institute of Scientific and Technical Information of China (English)

    Zhao Xiufen; Yin Guofu; Tian Guiyun; Yin Ying

    2008-01-01

    Automatic identification of flaws is very important for ultrasonic nondestructive testing and evaluation of large shaft. A novel automatic defect identification system is presented. Wavelet packet analysis (WPA) was applied to feature extraction of ultrasonic signal, and optimal Support vector machine (SVM) was used to perform the identification task. Meanwhile, comparative study on convergent velocity and classified effect was done among SVM and several improved BP network models. To validate the method, some experiments were performed and the results show that the proposed system has very high identification performance for large shafts and the optimal SVM processes better classification performance and spreading potential than BP manual neural network under small study sample condition.

  14. Shaft torsional oscillation interactions between turbo-generators in parallel in series compensated transmission systems

    Energy Technology Data Exchange (ETDEWEB)

    Mello, F.P. de

    1994-12-31

    Several investigators have raised the possibility of interaction between shaft systems of parallel units, particularly among identical units. The question addressed in this paper is the significance of this interaction between shaft systems of units coupled through the electrical system. A time domain model of two parallels units connected to an infinite bus trough a series compensated transmission is used to evaluate the phenomena. The same model is used to extract pertinent frequency response functions by Fourier processing of pulse response tests from which a frequency response analysis is performed to lend additional insight into the phenomena. (author) 8 refs., 13 figs., 3 tabs.

  15. Determination of Material for Shaft Design Using on Grey Correlation Analysis and TOPSIS Method

    Directory of Open Access Journals (Sweden)

    B. Siva Kumar

    2015-10-01

    Full Text Available Machines, automobiles, aircrafts and many other applications have shaft as major mechanical component which must have a proper design, in-order to have the efficient transmission of power from one element to another. For the design of shaft an appropriate range of evaluation, general product form and processing methods for material must be made. The selection of material should be done by using multiple attribute decision methods (MADM. In this paper, Grey Correlation Analysis and TOPSIS Method is proposed in order to decide a suitable material by considering different attributes and graphical representations are made for different attributes verse materials and vice versa.

  16. Research on a novel orientation algorithm of single-ring absolute photoelectric shaft encoder

    Institute of Scientific and Technical Information of China (English)

    CHEN Yun

    2007-01-01

    A novel single-ring absolute optical shaft encoder is designed by studying the encoding principle of traditional absolute optical shaft encoder in this paper. The description of the orientation algorithm of the encoder is specified,and an example for explaining the orientation arithmetic is given,which indicates that the theory of the encoder works. The visual interface to acquire signals of CCD is shown with VB,which provides reliable foundation to process data. The effective factors of measurement precision of the encoder are analyzed.

  17. Torsional Oscillation Characteristics of Rotary Shafts Based on Torsion and Bending Coupled Vibration

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    The torsional oscillation characteristics on the bending and torsion coupled vibration of rotary shaft system were investigated using the elasto-dynamic theory and other mathematic methods, such as difference approach, Fourier transform, and wavelet transform. It is concluded that mass eccentricity and other exciting modalities affect the bending and torsion coupled vibration of rotary shafts. Torsional vibration caused by bending vibration features linearity along with the change of amplitude of bending vibration. Meanwhile, energy spectrum concentrates on high frequency area with the wavelet analysis.

  18. Shut off butterfly valve with shaft-hubconnection re-stress device; Doppeltexzentrische Absperrklappe mit selbstnachspannender Welle-Klappenscheiben-Verbindung

    Energy Technology Data Exchange (ETDEWEB)

    Lanser, Axel [CTV-Armaturen GmbH, Nerdlen (Germany)

    2010-09-15

    The operation of shaft-hubconnection are using in torque transmission of machine parts and shut off valves as well. The new shaft-hubconnection re-stress device designed by CTV-Armaturen, have a lot of advantages in application. (orig.)

  19. Research on Stress and Strength of High Strength Reinforced Concrete Drilling Shaft Lining in Thick Top Soils

    Institute of Scientific and Technical Information of China (English)

    YAO Zhi-shu; CHANG Hua; RONG Chuan-xin

    2007-01-01

    High strength reinforced concrete drilling shaft linings have been adopted to solve the difficult problem of supporting coal drilling shafts penetrating through thick top soils. Through model experiments the stress and strength of such shaft linings are studied. The test results indicate that the load bearing capacity of the shaft lining is very high and that the main factors affecting the load bearing capacity are the concrete strength, the ratio of lining thickness to inner radius and the reinforcement ratio. Based on the limit equilibrium conditions and the strength theory of concrete under multi-axial compressive stressed state, a formula for calculating the load-bearing capacity of a high strength reinforced concrete shaft lining was obtained. Because the concrete in a shaft lining is in a multi-axial compressive stress state the compressive strength increases to a great extent compared to uni-axial loading. Based on experiment a formula for the gain factor in compressive strength was obtained: it can be used in the structural design of the shaft lining. These results have provided a basis for sound engineering practice when designing this kind of shaft lining structure.

  20. 78 FR 66071 - Proposed Information Collection; Slope and Shaft Sinking Plans (Pertains to Surface Work Areas of...

    Science.gov (United States)

    2013-11-04

    ... Safety and Health Administration Proposed Information Collection; Slope and Shaft Sinking Plans (Pertains to Surface Work Areas of Underground Coal Mines) AGENCY: Mine Safety and Health Administration, Labor... information collection for Slope and Shaft Sinking Plans, 30 CFR 77.1900. DATES: All comments must...

  1. Theoretical modelling, analysis and validation of the shaft motion and dynamic forces during rotor–stator contact

    DEFF Research Database (Denmark)

    Lahriri, Said; Santos, Ilmar

    2013-01-01

    This paper deals with the theoretical study of a horizontal shaft, partially levitated by a passive magnetic bearing, impacting its stator. Rigid body dynamics are utilised in order to describe the governing nonlinear equations of motion of the shaft interacting with a passive magnetic bearing an...

  2. 机车电机转轴及小齿轮轴断裂失效分析%Fracture Failure Analysis for Traction Motor Rotation Shaft and Pinion Shaft of Locomotive

    Institute of Scientific and Technical Information of China (English)

    彭志亮; 左华付; 肖先忠

    2011-01-01

    Fracture morphology, chemical composition, hardness and microstrueture were analyzed to find the fracture reason of traction motor rotation shaft and pinion shaft of a locomotive which were interference fit. The results showed that the rotation shaft and pinion shaft were all rotation bending fretting fatigue fracture, the main reasons of fracture were the fretting abrasion of the interference surface between rotation shaft and pinion shaft and stress concentration on the junction of the pinion shaft;s oil groove and hole, fatigue cracks initiated because of the stress concentration, and then extended under the action of rotation bending stress to fracture finally. The crack initiation and fracture of pinion shaft were earlier than those of rotation shaft_%为查目月某机车电机转轴以及与之过盈配合的小齿轮轴的断裂原因,对断口形貌、化学成分、硬度和显微组织进行了综合分析。结果表明:转轴及小齿轮轴的断裂均为旋转弯曲微动疲劳断裂;断裂原因主要是由于转轴与小齿轮轴过盈配合面的微动磨损以及小齿轮轴的油槽与油孔交界处的应力集中,应力集中导致疲劳裂纹的萌生,然后在旋转弯曲应力的作用下扩展直至断裂,小齿轮轴的起裂及断裂均先于转轴。

  3. Control of the low-frequency vibrations of elastic metamaterial shafts with discretized arc-rubber layers

    Science.gov (United States)

    Lixia, Li; Anjiang, Cai

    2016-06-01

    We propose a new kind of elastic metamaterial (EM) shaft with discretized arc-shaped rubber layers, which shows excellent low-frequency vibration properties. The band gaps of the shaft structure were analyzed by employing the finite element method. The proposed EM shaft exhibits much lower band gaps than the corresponding structures with the whole rubber ring. Furthermore, the band gaps can be modulated by tuning the arc angle and the number of the arc-shaped rubbers. Additionally, we observed that the first complete band gap tends to disappear when the arc angle of each arc-shaped rubber section is decreased but the arc number remains fixed because the arc angle more strongly affects the rotational stiffness than the transverse stiffness of the rubber layers. This new type of EM shafts could find potential application as a means to control the low-frequency vibrations of rotor shafts in mechanical engineering.

  4. 船舶推进轴系轴径倾斜对轴承负荷的影响%Effect of inclined shaft on the shafting alignment

    Institute of Scientific and Technical Information of China (English)

    陆金铭; 李儒凡; 倪杰

    2015-01-01

    Since propulsion shafting is affected by many dynamic factors of bearing arrangement and operation, the axis will have a certain degree of bending deformation.The inclined shaft leads to the change of bearing oil film thickness, so that the bearing pressure distribution changes.When the local pressure exceeds the allowable bearing pressure, it is easy to produce the local wear of bearing, so it is necessary to analyze the effect of mis-alignment on the lubrication characteristics of the journal bearing.The ship propulsion shafting is analyzed by u-sing the finite difference method for solving the Reynolds equation, the intermediate bearing and the bearings be-fore and after the stern shaft is calculated by making use of FORTRAN and MATLAB.The results show that when the shaft is inclined, local film pressure exceeds the allowable specific pressure; with the increase of the inclination angle, the maximum local pressure changes abruptly and the minimum oil film thickness decreases;its location moves to the stern, so that the oil film pressure and thickness distribution changed greatly.%船舶推进轴系由于受轴承布置及运行时各种动态因素的影响,轴线会有一定程度的弯曲变形.轴承中轴径的倾斜会导致轴承油膜厚度的变化,从而使轴承压力分布产生变化,当局部压力超过轴承允许比压时,易产生轴承局部区域磨损,因此有必要分析轴径倾斜对径向滑动轴承润滑性能的影响.对实船推进轴系进行分析,利用有限差分法求解Reynolds方程,用FORTRAN及MATLAB编程分别对艉管前轴承、艉管后轴承及中间轴承进行计算分析.结果表明:当轴径倾斜时,油膜局部压力超过允许比压,随着倾斜角度变大,局部最大压力突变,最小油膜厚度减小,其位置也向尾端倾斜,从而使油膜压力和厚度分布等发生了较大的边缘效应.

  5. Magnetic Actuation Connector Between Extension Shaft and Armature for Bottom Mounted Control Rod Drive Mechanism

    Energy Technology Data Exchange (ETDEWEB)

    Huh, Hyung; Cho, Yeong Garp; Kim, Jong In [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2013-10-15

    The electromagnet and armature inside the guide tube interact and produce magnetism, thus making the armature, connecting extension shaft and control rod move up and down to control the power of reactor. During the overhaul, the control absorber rod (CAR), extension shaft, and armature of BMCRDM are lifted together for closing a seal valve. But total length of CAR assembly is so long that it cannot be lifted due to exposure above the water level of pool which is strictly controlled. In addition to this, it is difficult to calibrate a position indicator and lifting force of electromagnet without armature assembly as a seal valve is closed. For this reason, it is necessary to install a disconnecting system between armature and extension shaft. Therefore, KAERI has developed magnetic actuation connector using plunger between armature and extension shaft for the bottom mounted control rod drive mechanism in research reactor. The results of a FEM and the experiments in this work lead to the following conclusions: The FEM result for the design of the magnetic actuation connector is compared with the measured lifting force of prototype production. As a result, it is shown that the lifting force of the prototype connector has a good agreement with the result of the FEM. A newly developed technique of prototype magnetic actuation connector which is designed by FEM analysis result is proposed.

  6. An Efficiency Optimizing Shaft Speed Control for Ships in Moderate Seas

    DEFF Research Database (Denmark)

    Blanke, Mogens; Pivano, Luca; Johansen, Tor Arne

    2007-01-01

    Ships in moderate sea experience time-varying thrust and torque load on the shaft of their prime mover. The reason is the varying inflow velocity to the propeller during the passage of a wave. This variation has been considered a nuisance to the main engine control where the induced fluctuations ...

  7. Feasibility Study on the Design of Reinforced Plastic Components for the LVTP (7) Vehicle Shafts

    Science.gov (United States)

    1984-12-01

    neat (pure) resin properties for LRF-092 and LRF-271. LRF-092 LRF-271 - Resin Casting Property (unaged) Property Value Property Value Tensile Strength...fiber properties (Table IV) and resin properties of (Epoxy-Anhydride). 34 4.3.1 Selection of a Shaft Composite Design The purpose of this study is to

  8. Radon dispersion modeling and dose assessment for uranium mine ventilation shaft exhausts under neutral atmospheric stability.

    Science.gov (United States)

    Xie, Dong; Wang, Hanqing; Kearfott, Kimberlee J; Liu, Zehua; Mo, Shunquan

    2014-03-01

    In the present study, the roles of atmospheric wind profiles in the neutral atmosphere and surface roughness parameters in a complex terrain were examined to determine their impacts on radon ((222)Rn) dispersion from an actual uranium mine ventilation shaft. Simulations were completed on (222)Rn dispersion extending from the shaft to a vulnerable distance, near the location of an occupied farmhouse. The eight dispersion scenarios for the ventilation shaft source included four downwind velocities (0.5, 1.0, 2.0 and 4.0 m s(-1)) and two underlying surface roughness characteristics (0.1 m and 1.0 m). (222)Rn distributions and elevated pollution regions were identified. Effective dose estimation methods involving a historical weighting of wind speeds in the direction of interest coupled to the complex dispersion model were proposed. Using this approach, the radiation effects on the residents assumed to be outside at the location of the farm house 250 m downwind from the ventilation shaft outlet were computed. The maximum effective dose rate calculated for the residents at the outside of the farm house was 2.2 mSv y(-1), which is less than the low limit action level of 3-10 mSv y(-1) recommended by the International Commission on Radiological Protection (ICRP) occupational exposure action level for radon.

  9. Treatment of ipsilateral hip and femoral shaft fractures with reconstructive intramedullary interlocking nail

    Institute of Scientific and Technical Information of China (English)

    吴立东; 吴琼华; 严世贵; 潘志军

    2004-01-01

    Objective: To evaluate the results of reconstructive intramedullary interlocking nail in the treatment of ipsilateral hip and femoral shaft fractures. Methods: From August 1997 to November 2001, 13 patients were treated with the reconstructive intramedullary interlocking nail. Nine patients were associated with ipsilateral femoral neck fractures, three with ipsilateral intertrochanteric fractures, and one with subtrochanteric fracture. Results: The follow-up time was from 6 to 38 months with an average of 14 months. All the femoral shaft and hip fractures healed up well. There was no nonunion of the femoral neck, and only one varus malunion. No patient had avascular necrosis of the femoral head. The average healing time for femoral neck fracture was 4.6 months and for shaft fracture 5.8 months. The joint movement and other functions were fairly resumed. Conclusions: The reconstructive intramedullary interlocking nail, with less trauma, reliable fixation, and high rate of fracture healing, is an ideal method of choice in the treatment of ipsilateral hip and femoral shaft fractures.

  10. Whole-genome shotgun sequencing of mitochondria from ancient hair shafts

    DEFF Research Database (Denmark)

    Gilbert, M Thomas P; Tomsho, Lynn P; Rendulic, Snjezana

    2007-01-01

    Although the application of sequencing-by-synthesis techniques to DNA extracted from bones has revolutionized the study of ancient DNA, it has been plagued by large fractions of contaminating environmental DNA. The genetic analyses of hair shafts could be a solution: We present 10 previously...

  11. A Method For Producing Hollow Shafts By Rotary Compression Using A Specially Designed Forging Machine

    Directory of Open Access Journals (Sweden)

    Tomczak J.

    2015-09-01

    Full Text Available The paper presents a new method for manufacturing hollow shafts, where tubes are used as billet. First, the design of a specially designed forging machine for rotary compression is described. The machine is then numerically tested with regard to its strength, and the effect of elastic strains of the roll system on the quality of produced parts is determined. The machine’s strength is calculated by the finite element method using the NX Nastran program. Technological capabilities of the machine are determined, too. Next, the results of the modeling of the rotary compression process for a hollow stepped shafts by the finite element method are given. The process for manufacturing hollow shafts was modeled using the Simufact.Forming simulation program. The FEM results are then verified experimentally in the designed forging machine for rotary compression. The experimental results confirm that axisymmetric hollow shafts can be produced by the rotary compression method. It is also confirmed that numerical methods are suitable for investigating both machine design and metal forming processes.

  12. Fault diagnostics for turbo-shaft engine sensors based on a simplified on-board model.

    Science.gov (United States)

    Lu, Feng; Huang, Jinquan; Xing, Yaodong

    2012-01-01

    Combining a simplified on-board turbo-shaft model with sensor fault diagnostic logic, a model-based sensor fault diagnosis method is proposed. The existing fault diagnosis method for turbo-shaft engine key sensors is mainly based on a double redundancies technique, and this can't be satisfied in some occasions as lack of judgment. The simplified on-board model provides the analytical third channel against which the dual channel measurements are compared, while the hardware redundancy will increase the structure complexity and weight. The simplified turbo-shaft model contains the gas generator model and the power turbine model with loads, this is built up via dynamic parameters method. Sensor fault detection, diagnosis (FDD) logic is designed, and two types of sensor failures, such as the step faults and the drift faults, are simulated. When the discrepancy among the triplex channels exceeds a tolerance level, the fault diagnosis logic determines the cause of the difference. Through this approach, the sensor fault diagnosis system achieves the objectives of anomaly detection, sensor fault diagnosis and redundancy recovery. Finally, experiments on this method are carried out on a turbo-shaft engine, and two types of faults under different channel combinations are presented. The experimental results show that the proposed method for sensor fault diagnostics is efficient.

  13. Fault Diagnostics for Turbo-Shaft Engine Sensors Based on a Simplified On-Board Model

    Science.gov (United States)

    Lu, Feng; Huang, Jinquan; Xing, Yaodong

    2012-01-01

    Combining a simplified on-board turbo-shaft model with sensor fault diagnostic logic, a model-based sensor fault diagnosis method is proposed. The existing fault diagnosis method for turbo-shaft engine key sensors is mainly based on a double redundancies technique, and this can't be satisfied in some occasions as lack of judgment. The simplified on-board model provides the analytical third channel against which the dual channel measurements are compared, while the hardware redundancy will increase the structure complexity and weight. The simplified turbo-shaft model contains the gas generator model and the power turbine model with loads, this is built up via dynamic parameters method. Sensor fault detection, diagnosis (FDD) logic is designed, and two types of sensor failures, such as the step faults and the drift faults, are simulated. When the discrepancy among the triplex channels exceeds a tolerance level, the fault diagnosis logic determines the cause of the difference. Through this approach, the sensor fault diagnosis system achieves the objectives of anomaly detection, sensor fault diagnosis and redundancy recovery. Finally, experiments on this method are carried out on a turbo-shaft engine, and two types of faults under different channel combinations are presented. The experimental results show that the proposed method for sensor fault diagnostics is efficient. PMID:23112645

  14. Balancing of a power-transmission shaft with the application of axial torque

    Science.gov (United States)

    Zorzi, E. S.; Flemming, D.

    1980-01-01

    Evaluation of power transmission shafting for high-speed balancing has shown that when axial torque is applied, the imbalance response is altered. An increase in synchronous excitation always occurs if the axial torque level is altered from the value used during balancing; this was the case even when the shaft was balanced with torque applied. The twisting of the long slender shaft produces a change in the imbalance distribution sufficient to disrupt the balanced state. This paper presents a review of the analytic development of a weighted least squares approach to influence coefficient balancing and a review of experimental results. The analytic approach takes advantage of the fact that the past testing has shown that the influence coefficients are not significantly affected by the application of axial torque. The 3.60-m (12-ft) long aluminum shaft, 7.62 cm (3 in.) in diameter was run through the first flexural critical speed at torque levels ranging from zero-torque to 903.8 N-M (8000 lb-in.) in 112.9 N-M (1000 lb-in.) increments. Good comparison was achieved between predicted and experimental results.

  15. An evaluation of spindle-shaft seizure accident sequences for the Schenck Dynamic Balancer

    Energy Technology Data Exchange (ETDEWEB)

    Bott, T.F.; Fischer, S.R.

    1998-11-01

    This study was conducted at the request of the USDOE/AL Dynamic Balancer Project Team to develop a set of representative accident sequences initiated by rapid seizure of the spindle shaft of the Schenck dynamic balancing machine used in the mass properties testing activities in Bay 12-60 at the Pantex Plant. This Balancer is used for balancing reentry vehicles. In addition, the study identified potential causes of possible spindle-shaft seizure leading to a rapid deceleration of the rotating assembly. These accident sequences extend to the point that the reentry vehicle either remains in stable condition on the balancing machine or leaves the machine with some translational and rotational motion. Fault-tree analysis was used to identify possible causes of spindle-shaft seizure, and failure modes and effects analysis identified the results of shearing of different machine components. Cause-consequence diagrams were used to help develop accident sequences resulting from the possible effects of spindle-shaft seizure. To make these accident sequences physically reasonable, the analysts used idealized models of the dynamics of rotating masses. Idealized physical modeling also was used to provide approximate values of accident parameters that lead to branching down different accident progression paths. The exacerbating conditions of balancing machine over-speed and improper assembly of the fixture to the face plate are also addressed.

  16. A new gasification and melting incineration process of MSW with co-current shaft furnace.

    Science.gov (United States)

    Zhao, Wei; Wang, Qi; Zou, Zongshu; Liu, Haixiao; Zheng, Hongxia; Zhang, Lei

    2009-01-01

    In all the municipal solid waste (MSW) disposal technology, incineration with gasification and melting has been taken as a environmentally sound and zero emission technology owing to avoiding second-pollution of heavy metals and dioxin. In this background, a new direct gasification and melting incineration process with co-current shaft furnace is put forward. In this process, MSW and combustion-supporting air are co-current from top to bottom in a shaft furnace. Fuel gas from pyrolysis and gasification burns completely in the bottom in order to offer energy for slag melting. The simulation experiment of the co-current shaft furnace has been done. The results of simulation experiment show that the temperature on the condition of co-current is much higher than on the condition of countercurrent at the bottom of reaction tube and so is the CO2 quantity discharged from reaction tube. It can be concluded that the co-current shaft furnace is more suitable for direct gasification and melting incineration process.

  17. BIFURCATION OF A SHAFT WITH HYSTERETIC-TYPE INTERNAL FRICTION FORCE OF MATERIAL

    Institute of Scientific and Technical Information of China (English)

    丁千; 陈予恕

    2003-01-01

    The bifurcation of a shaft with hysteretic internal friction of material was analysed. Firstly, the differential motion equation in complex form was deduced using Hamilton principle. Then averaged equations in primary resonances were obtained using the averaging method. The stability of steady-state responses was also determined. Lastly, the bifurcations of both normal motion (synchronous whirl) and self-excited motion (nonsynchronous whirl) were investigated using the method of singularity. The study shows that by a rather large disturbance, the stability of the shaft can be lost through Hopf bifurcation in case the stability condition is not satisfied. The averaged self-excited response appears as a type of unsymmetrical bifurcation with high orders of co-dimension. The second Hopf bifurcation, which corresponds to double amplitude-modulated response, can occur as the speed of the shaft increases. Balancing the shaft carefully to decrease its unbalance level and increasing the external damping are two effective methods to avoid the appearance of the self-sustained whirl induced by the hysteretic internal friction of material.

  18. Modeling and Dynamical Behavior of Rotating Composite Shafts with SMA Wires

    Directory of Open Access Journals (Sweden)

    Yongsheng Ren

    2014-01-01

    Full Text Available A dynamical model is developed for the rotating composite shaft with shape-memory alloy (SMA wires embedded in. The rotating shaft is represented as a thin-walled composite of circular cross-section with SMA wires embedded parallel to shaft’s longitudinal axis. A thermomechanical constitutive equation of SMA proposed by Brinson is employed and the recovery stress of the constrained SMA wires is derived. The equations of motion are derived based on the variational-asymptotical method (VAM and Hamilton’s principle. The partial differential equations of motion are reduced to the ordinary differential equations of motion by using the Galerkin method. The model incorporates the transverse shear, rotary inertia, and anisotropy of composite material. Numerical results of natural frequencies and critical speeds are obtained. It is shown that the natural frequencies of the nonrotating shaft and the critical rotating speed increase as SMA wire fraction and initial strain increase and the increase in natural frequencies becomes more significant as SMA wire fraction increases. The initial strain of SMA wires appears to have marginal effect on dynamical behaviors of the shaft. The actuation performance of SMA wires is found to be closely related to the ply-angle.

  19. Influential Force: Shafts and the Diffusion of Knowledge at the Fin de Siécle

    Directory of Open Access Journals (Sweden)

    Matthew Beaumont

    2006-10-01

    Full Text Available The feminist journal 'Shafts', which ran from 1892 to 1899, edited by Margaret Shurmer Sibthorp, was an important forum for the discussion of women's oppression and liberation at the fin de siécle - though it has received comparatively little scholarly attention. In this article I outline the significance of Shafts' sometimes contradictory contribution to the social and political debates of the period, focusing in particular on the convergence of enlightenment and anti-enlightenment discourses in its pages. The relationship of these discourses is knotted together around the concept of ‘influential force', which is of signal importance to the argument of the opening article of the journal's inaugural issue, entitled ‘Shafts of Thought'. I contend that, to the main contributors of 'Shafts', the metaphorical significance of the notion of ‘influential force', which draws on contemporaneous scientific and spiritualist theories, lies in its capacity for reconceptualising the social and intellectual relations that obtain, at the end of the nineteenth century, among the readers of a progressive periodical.

  20. Biomechanical Study of the Fixation Strength of Anteromedial Plating for Humeral Shaft Fractures

    Directory of Open Access Journals (Sweden)

    Yin-Feng Zheng

    2016-01-01

    Conclusions: Anteromedial plating was superior to anterolateral or posterior plating in all mechanical tests except in AP four-point bending fatigue tests compared to the anterolateral plating group. We can suggest that anteromedial plating is a clinically safe and effective way for humeral shaft fractures.

  1. Isolated ulnar shaft fractures. Comparison of treatment by a functional brace and long-arm cast

    DEFF Research Database (Denmark)

    Gebuhr, Peter Henrik; Hölmich, P; Orsnes, T;

    1992-01-01

    In a prospective study, we randomly allocated 39 patients with isolated fractures of the lower two-thirds of the ulnar shaft to treatment either by a prefabricated functional brace or a long-arm cast. Significantly better wrist function and a higher percentage of satisfied patients were found in ...

  2. Torsional natural frequency tuning by means of pneumatic flexible shaft couplings

    OpenAIRE

    2015-01-01

    This article deals with the use of pneumatic flexible shaft couplings as device for tuning torsional natural frequencies of mechanical systems. These couplings are using air bellows as flexible elements. Their torsional stiffness can be changed by air pressure change, the natural frequencies of whole mechanical system may be adjusted on desired value.

  3. Torsional natural frequency tuning by means of pneumatic flexible shaft couplings

    Directory of Open Access Journals (Sweden)

    Peter KAŠŠAY

    2015-12-01

    Full Text Available This article deals with the use of pneumatic flexible shaft couplings as device for tuning torsional natural frequencies of mechanical systems. These couplings are using air bellows as flexible elements. Their torsional stiffness can be changed by air pressure change, the natural frequencies of whole mechanical system may be adjusted on desired value.

  4. Structural Modifications for Torsional Vibration Control of Shafting Systems Based on Torsional Receptances

    Directory of Open Access Journals (Sweden)

    Zihao Liu

    2016-01-01

    Full Text Available Torsional vibration of shafts is a very important problem in engineering, in particular in ship engines and aeroengines. Due to their high levels of integration and complexity, it is hard to get their accurate structural data or accurate modal data. This lack of data is unhelpful to vibration control in the form of structural modifications. Besides, many parts in shaft systems are not allowed to be modified such as rotary inertia of a pump or an engine, which is designed for achieving certain functions. This paper presents a strategy for torsional vibration control of shaft systems in the form of structural modifications based on receptances, which does not need analytical or modal models of the systems under investigation. It only needs the torsional receptances of the system, which can be obtained by testing simple auxiliary structure attached to relevant locations of the shaft system and using the finite element model (FEM of the simple structure. An optimization problem is constructed to determine the required structural modifications, based on the actual requirements of modal frequencies and mode shapes. A numerical experiment is set up and the influence of several system parameters is analysed. Several scenarios of constraints in practice are considered. The numerical simulation results demonstrate the effectiveness of this method and its feasibility in solving torsional vibration problems in practice.

  5. Outcome of non-operative management of femoral shaft fractures in children

    Directory of Open Access Journals (Sweden)

    Akinyoola A

    2011-01-01

    Full Text Available Background: Femoral shaft fractures are common injuries in childhood. There is paucity of information on their presentation and outcome of the available treatment methods in the African population. This study evaluated the outcome of non-operative methods of treatment of femoral shaft fractures in our centre. Patients and Methods: A retrospective review of the database of children aged 14 years and below with femoral shaft fractures treated non-operatively over a 10-year period. Results: A total of 134 patients with 138 fractures met the study criteria. This consisted of 71 boys (mean age = 6.1 years ± SD and 63 girls (mean age = 6.5 years ± SD. Pedestrian vehicular accident was the most common cause of femoral shaft fractures in the study population. The midshaft was the most common site of fractures. There were associated injuries to other parts of the body (especially head injury in 34.3% of the patients. The commonest mode of treatment was skin traction only (87.7%. The mean time to fracture union was 4.9 weeks ± SD (range = 3-15 weeks. The mean length of hospitalisation was 6.7 weeks ± SD (range = 5 days-11 weeks. There was a fairly strong positive correlation between the length of hospitalisation and the presence of associated injuries, especially head injury, upper limb fractures and bilaterality of the fractures. The mean total cost of treatment was #7685 (Naira or $51.2 (range = $14.2-$190. At the last follow up, 97.8% of the fractures united without significant angulation or shortening. Conclusion: The outcome of non-operative treatment of femoral shaft fractures in our setting is comparable to the results of other workers. Methods of treatment that shorten the length of hospitalisation without unduly increasing cost should be encouraged.

  6. Study of Ender’s Nailing in Shaft Femur Fractures of Older Children

    Directory of Open Access Journals (Sweden)

    Ladani HG

    2014-12-01

    Full Text Available Background: Fractures in shaft femur in children are relatively common. Various methods of treating these fractures starting from non operative to methods like closed intramedullary nailing are at our disposal. Traditionally non operative methods are acceptable and find wide acceptance even today in very young children. However in older children certain problems are encountered like failure to control angulation and shortening, prolonged immobilization which causes very much discomfort & the overgrowth phenomenon. In view of above difficulties, closed intramedullary nailing was attempted in older children and adolescents. I have tried to study 23 cases of shaft femur fractures in older children treated by Ender’s nails. Methodology: 22 pts., out of which one having bilateral # shaft femur (total 23 #s with age ranging from 7 to 16 yrs. were studied. 3 pts. having polio limbs studied separately. Fracture was in upper third shaft femur in 5 pts., middle third in 13 pts., lower third in 3pts. & involving more than one region in 2 pts. Fracture was transverse in 6 pts., spiral in 3 pts., oblique in 12 pts.& comminuted in 2 pts.. Results: Average union time was 10 weeks except in polio pts. where it was delayed. No nonunion, no infection. Excellent hip & knee movements in almost all pts. Out of 20 pts. ( except polio pts. limb length was equal in 17 pts., one pt. was having 1 cm. lengthening & 2 pts. were having shortening ( 1cm. & 2 cm.. Conclusion: Results of this study strongly favor the use of Ender’s nailing in shaft femur fractures in older children. Second surgery of implant removal is mandatory. Closed reduction can usually be achieved if surgery is performed earlier.

  7. Torsional Behaviour and Finite Element Analysis of the Hybrid Laminated Composite Shafts: Comparison of VARTM with Vacuum Bagging Manufacturing Method

    Directory of Open Access Journals (Sweden)

    Mehmet Emin Taşdelen

    2016-01-01

    Full Text Available Braided sleeve composite shafts are produced and their torsional behavior is investigated. The braided sleeves are slid over an Al tube to create very strong and rigid tubular form shafts and they are in the form of 2/2 twill biaxial fiber fabric that has been woven into a continuous sleeve. Carbon and glass fibers braided sleeves are used for the fabrication of the composite shafts. VARTM (vacuum assisted resin transfer molding and Vacuum Bagging are the two different types of manufacturing methods used in the study. Torsional behaviors of the shafts are investigated experimentally in terms of fabrication methods and various composite materials parameters such as fiber types, layer thickness, and ply angles. Comparing the two methods in terms of the torque forces and strain angles, the shafts producing entirely carbon fiber show the highest torque capacities; however, considering the cost and performance criteria, the hybrid shaft made up of carbon and glass fibers is the optimum solution for average demanded properties. Additionally, FE (finite element model of the shafts was created and analyzed by using ANSYS workbench environment. Results of finite element analysis are compared with the values of twisting angle and torque obtained by experimental tests.

  8. Deformation Analysis and Stability Evaluation of the Main Shaft at Jinchuan Mine No.3

    Institute of Scientific and Technical Information of China (English)

    ZHAO Qian-li; GAO Qian; ZHANG Zhou-ping; XIAO Wei-guo

    2007-01-01

    Unexpected, serious deformation failures have occurred during construction of a main shaft. A study of construction parameters of the main shaft is required. First, the stability of the shaft and wall-rock is investigated by numerical methods. The modeling results are as follows: The convergence of shaft liner is greater than 60 mm at a depth of 650 m; the maximum principal stress in the liner approaches 190 MPa, which exceeds the strength of the liner, so it is inevitable that the liner deform locally. Second, stability analysis of shafts with different liner thicknesses has been completed. The results have the following features: If the depth where the liner thickness is increases from 400 mm to 500 mm is 650 meters, the convergence deformation of the liner is reduced by 3.4 mm while the maximum principal stress is reduced by 5 MPa. At a depth of 250 m if the liner thickness is increased from 400 mm to 500 mm the convergence of the liner is reduced by 1.5 mm while the maximum principal stress is reduced by 10 MPa. Therefore, increasing the liner thickness has little effect on liner convergence but can reduce the maximum principal stress in the liner. The thickness of the liner can be increased to reduce the maximum principal stress and increase the capacity for shear deformation. Finally, construction techniques employing releasing-displacements have been numerically simulated. The conclusions are that as the releasing displacement is increased the convergence of the surrounding rock increases linearly while the convergence of the lining decreases linearly. The plastic zone in the surrounding rock mass at first increases linearly but then, at a release-displacement of 95 mm, expands rapidly. These conclusions show that use of suitable releasing displacement can increase the self-supporting capacity of the surrounding rock. But when the releasing displacement exceeds 95 mm the plastic zone rapidly enlarges and stability rapidly decreases. The maximum principal

  9. Auxiliary mass damper for Cardan suspended gyro

    Science.gov (United States)

    Rosenberg, J.; Kahana, A.

    The paper describes a damping system for a spin-stabilized platform which involves the use of an auxiliary mass connected to the gimbal system by means of a spring and a viscous dash-pot. The damper inertia is insignificant in comparison with the platform inertia, resulting in a simplified model in which the nutational frequency is taken to be the forced frequency. An analysis is made of the interaction between the stabilized platform and the damper, which causes the appearance of three natural frequencies instead of the nutational frequency. The experimental realization of the auxiliary mass damper is discussed.

  10. Nonlinear Dynamic Characteristic Analysis of the Shaft System in Water Turbine Generator Set

    Institute of Scientific and Technical Information of China (English)

    MA Zhenyue; SONG Zhiqiang

    2009-01-01

    A 3D finite element vibration model of water turbine generator set is constructed considering the coupling with hydropower house foundation. The method of determining guide bearing dynamic characteristic coefficients according to the swing of the shaft is proposed, which can be used for studying the self-vibration characteristic and stability of the water turbine generator set. The method fully considers the complex supporting boundary and loading conditions; especially the nonlinear variation of guide bearing dynamic characteristic coefficients and the coupling effect of the whole power-house foundation. The swing and critical rotating speed of an actual generator set shaft system are calculated. The simulated results of the generator set indicate that the coupling vibration model and calculation method presented in this paper are suitable for stability analysis of the water turbine generator set.

  11. [Bilateral stress fracture of the mid-tibial shaft in a professional dancer].

    Science.gov (United States)

    Tomčovčík, L; Tomčovčíková, A

    2011-01-01

    Stress fractures of the anterior cortex of the mid-tibial shaft in dancers are rare, with a 1.4 % incidence in injured eli- te dancers. Treatment can be difficult and long-lasting and can seriously influence the dancer's career. The authors pre- sent the case of a 26-year-old professional dancer of a folk dance ensemble who suffered rare simultaneous bilateral mid-tibial shaft stress fractures. A conservative method of treatment with avoiding exercise and dancing activities resulted in the resolution of symptoms and healing of the fractures after 6 months. The patient finished his dancing career because of the necessity of a prolonged therapy interfering with his dancing activities. Current options of the treatment are also presented.

  12. Influence of parameters detuning on induction motor NFO shaft-sensorless scheme

    Directory of Open Access Journals (Sweden)

    KULIC, F.

    2010-11-01

    Full Text Available In this paper, the parameter sensitivity analysis of shaft-sensorless induction motor drive with natural field orientation (NFO scheme is performed. NFO scheme calculates rotor flux position using the rotor flux vector reference only, does not require significant processor power and therefore it is suitable for low cost shaft sensorless drives. This concept also eliminates the need for sensitive stator voltage vector integration and it is usable in low rotor speed range. However, low speeds are coupled with low stator voltage amplitudes, which inflate the NFO scheme sensitivity to an error in stator resistance parameter. Similar problems can also take place if mutual inductance parameter is detuned, but this time in whole speed range. This paper investigates the influence of each parameter error on the NFO control steady state characteristics and dynamic performance.

  13. Simulation Analysis of Spherical Mechanical Seal Property of Marine Stern Shaft

    Directory of Open Access Journals (Sweden)

    Zhou Xu Hui

    2016-01-01

    Full Text Available The finite element model of spherical mechanical seal wasestablished with ANSYS, and the influence of seawater pressure, shaft speed and other factors on the sealing performance was discussed. The study results show that local contact situation of the spherical mechanical seal is in the outside of the seal rings, and both maximum contact pressure and temperature appearat the same position. As sea water pressure and stern shaft rotary speed are increased, the contact pressure and temperature of the spherical seal surface are raised, and when the contact pressure of seal surface is 0, the spherical seal surface forms two zones including contact one and clearance zone. The former is near the outside of the seal ring, the lateris close to the inside of one. These research results are of important theoretical significance and engineering application value for the development of new kinds of mechanical seals, and improvement of both safety and survivability of underwater vehicles.

  14. Mutations in Three Genes Encoding Proteins Involved in Hair Shaft Formation Cause Uncombable Hair Syndrome

    DEFF Research Database (Denmark)

    Ü Basmanav, F Buket; Cau, Laura; Tafazzoli, Aylar

    2016-01-01

    Uncombable hair syndrome (UHS), also known as "spun glass hair syndrome," "pili trianguli et canaliculi," or "cheveux incoiffables" is a rare anomaly of the hair shaft that occurs in children and improves with age. UHS is characterized by dry, frizzy, spangly, and often fair hair that is resistant...... in the majority of UHS case subjects. The two enzymes PADI3 and TGM3, responsible for posttranslational protein modifications, and their target structural protein TCHH are all involved in hair shaft formation. Elucidation of the molecular outcomes of the disease-causing mutations by cell culture experiments...... and tridimensional protein models demonstrated clear differences in the structural organization and activity of mutant and wild-type proteins. Scanning electron microscopy observations revealed morphological alterations in hair coat of Padi3 knockout mice. All together, these findings elucidate the molecular genetic...

  15. Notch Sensitivity Factor Determination With Artificial Neural Network For Shafts Under The Bending Stress

    Directory of Open Access Journals (Sweden)

    Murat Tolga Özkan

    2013-01-01

    Full Text Available Notch, hole, tap and a variety of geometric shapes such as curves or discontinuities can be found with various reasons in the design of Machine Element. Stress is caused by sudden changes in section aggregating. Stress concentration can occur with the reason of material features of size or direction of forces application. This type of stress concentration in the material brings out the effect of notch. Notch impact can lead to distortions and breakage of materials. In this study, the notch sensitivity factor values have been modelled Artificial Neural Networks (ANN for shafts that is under the influence of bending stress, and the accuracy of the model has been verified by using Statistica software. The model has been developed using Pythia. With this software, the user can be obtained the accurate value by inputing shaft dimension and the applied force without the need for notch sensitivity factor tables and any calculations.

  16. Simulation of moving boundary of the reaction shaft in a flash smelting furnace

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    As to solve the online monitoring of the inner temperature and freezing profile of the reaction shaft of flash smelting furnace, simulation of the wall in the reaction shaft in a flash smelting furnace was made through numerical computation. The computational results are very near the data got in site. The error of the moving boundary is approximately 3 %, and that of the temperature is less than 5 %. It is proved that the simulation software is applicable for practice to monitor the temperature and moving boundary inside the hearth online. Based on a large number of the data computed, the relation between the change of the moving boundary and inner temperature is summarized, and the great influence of the cooling system on the forming and stability of the moving boundary inside the hearth is emphasized, which provide the theoretical bases for optimizing the flash smelting operation.

  17. Shaft Position Influence on Technical Characteristics of Universal Two-Stages Helical Speed Reducers

    Directory of Open Access Journals (Sweden)

    Мilan Rackov

    2005-10-01

    Full Text Available Purchasers of speed reducers decide on buying those reducers, that can the most approximately satisfy their demands with much smaller costs. Amount of used material, ie. mass and dimensions of gear unit influences on gear units price. Mass and dimensions of gear unit, besides output torque, gear unit ratio and efficiency, are the most important parameters of technical characteristics of gear units and their quality. Centre distance and position of shafts have significant influence on output torque, gear unit ratio and mass of gear unit through overall dimension of gear unit housing. Thus these characteristics are dependent on each other. This paper deals with analyzing of centre distance and shaft position influence on output torque and ratio of universal two stages gear units.

  18. A study on the characterization of smoke movement in shafts with different fire source positions

    Institute of Scientific and Technical Information of China (English)

    Zhu Jie; Yang Tianyou; Wu Jianbo; Du Lulu

    2013-01-01

    In this study,experimental and numerical simulation methods were combined to simulate the changing course of the temperature and velocity fields in nine different fire scenes. The characteristics of smoke movement in shafts with different fire source position factors (h/H) were quantitatively investigated,and the non-dimensional fitting function between the fire source position factors and the maximum temperature was deduced. The results showed that the location of the neutral plane moved upward as the fire source rose,and all the generated smoke spread to the upper areas;however,there was barely any smoke in the lower areas. The maximum temperature was inversely proportional to the fire source position factor;the higher the source position is,i.e. the higher the ra-tio factor is,the lower the maximum temperature is in the shaft. The experimental verification of the fire dynamics simulator (FDS) showed good results.

  19. Experimental Investigation of A Twin Shaft Micro Gas-Turbine System

    Science.gov (United States)

    Sadig, Hussain; Sulaiman, Shaharin Anwar; Ibrahim, Idris

    2013-06-01

    Due to the fast depletion of fossil fuels and its negative impact on the environment, more attention has been concentrated to find new resources, policies and technologies, which meet the global needs with regard to fuel sustainability and emissions. In this paper, as a step to study the effect of burning low calorific value fuels on gas-turbine performance; a 50 kW slightly pressurized non-premixed tubular combustor along with turbocharger based twin shaft micro gas-turbine was designed and fabricated. A series of tests were conducted to characterize the system using LPG fuel. The tests include the analysis of the temperature profile, pressure and combustor efficiency as well as air fuel ratio and speed of the second turbine. The tests showed a stable operation with acceptable efficiency, air fuel ratio, and temperature gradient for the single and twin shaft turbines.

  20. Numerical Simulation and Experimental Research on Hydrodynamic Performance of Propeller with Varying Shaft Depths

    Institute of Scientific and Technical Information of China (English)

    郭春雨; 赵大刚; 孙瑜

    2014-01-01

    In order to study hydrodynamic performance of a propeller in the free surface, the numerical simulation and open-water experiments are carried out with varying shaft depths of propeller. The influences of shaft depths of a propeller on thrust and torque coefficient in calm water are mainly studied. Meanwhile, this paper also studies the propeller air-ingestion under special working conditions by experiment and theoretical calculation method, and compares the calculation results and experimental results. The results prove that the theoretical calculation model used in this paper can imitate the propeller air-ingestion successfully. The successful phenomenon simulation provides an essential theoretical basis to understand the physical essence of the propeller air-ingestion.

  1. An investigation the effects of geometric tolerances on the natural frequencies of rotating shafts

    Directory of Open Access Journals (Sweden)

    Ali Akbar Ansarifard

    2015-04-01

    Full Text Available This paper presents the effects of geometric tolerances on the rotating shafts natural frequencies. Due to modeling the tolerances, a code is written in MATLAB 2013 software that produces deviated points. Deviated points are controlled by different geometric tolerances, including cylindricity, total run-out and coaxiality tolerances. Final surfaces and models passing through the points are created using SolidWorks 2013 software and finally modal analysis is carried out with the FE software. It is observed whatever the natural frequency is higher or the geometric tolerances are greater, the real and ideal shafts natural frequencies are more distant. Also difference percentage between ideal and real frequencies is investigated. The results show that the percentage value is approximately constant for every mode shapes.

  2. Performance investigation of side-coupled interlaced symmetric-shaft-shape photonic crystal sensor arrays

    Science.gov (United States)

    Fu, Zhongyuan; Zhou, Jian; Huang, Lijun; Sun, Fujun; Tian, Huiping

    2016-12-01

    We design symmetric-shaft-shape photonic crystal sensor arrays (SSPhCSAs) which can be used in refractive index sensing, and the performance of the structure is investigated. The structure consists of four symmetric-shaft-shape photonic crystal (SSPhC) cavities side-coupled to a W1 photonic crystal (PhC) waveguide. Each cavity has slightly different cavity spacing with different resonant frequency. By using two dimensional finite-difference time-domain (2D-FDTD) method, the simulation result obtained indicates the performance of the sensor arrays. The sensitivities of the four sensor units are 178, 252, 328 and 398 nm/RIU, respectively, with the detection limit of 10-3. The crosstalk lower than 20 dB is obtained.

  3. Evaluation of the reproducibility of the AO/ASIF classification for humeral shaft fractures☆

    Science.gov (United States)

    Pignataro, Gustavo Soriano; Junqueira, André Elias; Matsunaga, Fabio Teruo; Matsumoto, Marcelo Hide; Belloti, João Carlos; Tamaoki, Marcel Jun Sugawara

    2015-01-01

    Objective To evaluate the reproducibility of the AO/Asif classification for humeral shaft fractures. Methods Consecutive radiographs of the arm in both anteroposterior and lateral view from 60 patients with humeral shaft fractures were analyzed. Six observers who were familiar with the AO/Asif classification (three shoulder and elbow surgery specialists and three general orthopedists) were selected to make the analysis, which was done at three different times. The data were subjected to statistical analysis using the kappa coefficient. Results The intra and interobserver concordance was statistically significant in all the analyses. Conclusions All the evaluators showed concordance between the three evaluations that was considered to be statistically significant. However, the highest values were found among the specialists. PMID:26417565

  4. Diagnosis of the Thermal Bow of a Shaft in a Three Stage Centrifugal Compressor

    Institute of Scientific and Technical Information of China (English)

    2003-01-01

    In practice many turbo-machines driven by motors are started up to operational speed within a very short time, i.e. in less than 20 seconds. For this type of machines the compatibility of thermal deformation of the rotor structure must be taken into account in the machine design, or the thermal deformation will be constrained and a huge resultant force can cause the shaft bending and consequently resulting in violent vibrations. In this paper, detection of thermal bow of a shaft in a three stage centrifugal compressor in a petrochemical plant is presented. The diagnostic results show that the thermal bow was induced by the incompatibility of axial thermal deformation of the rotor structure. A remedial action allowing free axial thermal expansion of the outer parts of the rotor is suggested.

  5. MONOLATERAL LOW-INVASIVE TREATMENT OF HUMERAL SHAFT FRACTURE IN CHILDREN

    Directory of Open Access Journals (Sweden)

    V. P. Kuzmin

    2012-01-01

    Full Text Available Humeral fractures in children are from 4 up to 10% of the general number of child fractures. Recently the trend is marked to expansion of indications to operative treatment despite of mainly conservative treatment of humeral shaft fractures. The experience of humeral shaft fractures operative treatment with use of Ender nails was analyzed. 8 humeral bones were treated with use of 2 nails, 15 humeral bones - with use of 1 nail only. The good and excellent results were received in both groups of patients. At the same time group with monolateral osteosynthesis (with 1 nail had statistically significant (p<0,01 decreasing of surgery time (average difference 16 min, and also it had statistically significant (p <0,001 decreasing of X-ray exposition time (average difference 23 sec in comparison with group where the osteosynthesis was done with use of 2 nails. The results received in study show necessity of the further work for this direction.

  6. Longitudinal femoral shaft due to bone insufficiency. A review of three cases.

    Science.gov (United States)

    Maraval, Anne; Grados, Franck; Royant, Valérie; Damade, Richard; Boulu, Gilles; Fardellone, Patrice

    2003-12-01

    We report three new cases of longitudinal femoral shaft fracture due to bone insufficiency and review the eight cases reported in the literature. The typical patient is a woman older than 65 years of age who present with mechanical pain in the thigh and/or groin. Palpation of the thigh may reproduce the pain. The diagnosis is often made late because the radiographs are normal initially. However, an early and consistent finding is increased radionuclide uptake along the femoral shaft. The fracture line is readily evidenced by computed tomography but may be difficult to see on magnetic resonance imaging. Use of crutches for 6 weeks to protect the bone from weight bearing ensures healing of the fracture.

  7. a Study on Fracture Characteristics of the SM53C Used in the Cam Shaft

    Science.gov (United States)

    Jeon, Hyun-Bae; Song, Tae-Hoon; Park, Sung-Ho; Huh, Sun-Chul; Park, Won-Jo

    This experimental study investigates the fracture characteristics of the camshaft made with newly developed SM53C material. As part of the countermeasure, use the surface hardening heat treatment. Cam shaft which is a part of automobile engine is very essential when traveling and significant to fuel injection timing. Stiffness and efficiency are important for automobile sash which have a durability of the engine. High hardness and durability are necessary, because engine output is affected by cam shaft directly. So, high-frequency induction hardening is very important because of increasing the surface strength. The shape of hardening depth, hardened structure, hardness, and fracture characteristics of SM53C composed by carbon steel are also investigated.

  8. Optimization Design of Cardan Universal Joint Driving of Automotive Steering System%汽车转向系统十字轴万向节传动优化设计

    Institute of Scientific and Technical Information of China (English)

    胡国强; 岳红旭

    2011-01-01

    转向力是汽车操纵稳定性中一项重要的评价指标,其力矩波动直接影响驾驶感觉。文章对汽车转向轴的布置与力矩波动的关系进行了分析,并针对某车型转向系统的十字轴万向节结构进行优化设计。优化结果在matlab软件里仿真,得到较好的结果,波动力矩在允许的范围内。并得出最佳的中间轴相位角及轴系布置方案,对转向系统的优化设计有一定的参考价值,可作为实际车型开发中传动优化设计的技术依据。%Steering force is a very important evaluation index in vehicle controll stability;the torque fluctuation directly affects driving feeling.The relationship between the steering shaft arrangement and torque fluctuations is analyzed,and optimization design of cross axis universal structure in a car steering system is conducted.The optimization results are simulated in Matlab software and better results are achieved.The fluctuation torque is in permitted range.The best countershaft phase angle and shafting arrangement solution is gained.It provides reference for optimization design of steering system;and it can be used as technical basis of transmission optimization design in developing automobiles.

  9. Modeling and experimental validation of the dispersion of 222Rn released from a uranium mine ventilation shaft

    Science.gov (United States)

    Xie, Dong; Wang, Hanqing; Kearfott, Kimberlee J.

    2012-12-01

    Radon (222Rn) found in uranium mine shaft ventilation exhaust gases could pose hazards to the surrounding environment and the public by virtue of its progeny. Radon migration under complex terrain is complicated by pollution source characteristics, geographical features of the dispersion region, meteorological conditions and precipitation. Fluid dynamics computations of 222Rn dispersion are performed for uranium mine shaft exhausts for complex models of the actual physical terrain corresponding to a mine in the Jiangxi Province of China. The eight cases studied included a ventilation shaft source, four downwind velocities (0.5, 1.0, 2.0, 4.0 m s-1) and two underlying surface roughness characteristics (0.1 m, 1.0 m). 222Rn distributions in the vicinity of uranium mine ventilation shaft are computed and compared with field measurements.

  10. Is it possible to win back a part of coal resources confined to the safety pillar of a pit shaft

    Energy Technology Data Exchange (ETDEWEB)

    Krzysztof Ogieglo; Mieczyslaw Lubryka; Jerzy Sliwinski; Piotr Malkowski [Stone Coal Mine ' JAS-MUS' , Jastrzcbic (Poland)

    2003-07-01

    Results of the analysis of the impact of exploitation carried out in three mines of Jastrzebie Mining Joint Stock Company, in Poland close to pillars and exploitation encroaching upon safety pillars of 4 pit shafts on deformation of and damage to pit shaft pipes have been described in this paper. For some mines a period has been analyzed even since 1965. Making use of measurements and observations gained in natural conditions and numeric simulation in a method of finite elements with the use of COSMOS/M program a thesis has been proved that in the conditions of stone coal mines with the increase of the depth of exploitation there is a possibility of partial disturbance of defined boundaries of pillars of pit shafts without damaging and deforming these pit shafts. The course of walls prolonged in this way allows additional extraction without additional expenses. 7 refs., 9 figs.

  11. Technical Note: Example of the Application of Jet Grouting to the Neutralisation of Geotechnical Hazard in Shaft Structures

    Directory of Open Access Journals (Sweden)

    Dybeł Piotr

    2015-09-01

    Full Text Available The article presents a geotechnical hazard neutralisation technology for shaft structures. The diagnosis of problems with uncontrolled subsidence of the ventilation duct provided by the authors enabled the development of a schedule of works required for the protection and reinforcement of foundation soil in the shaft area. The technology of protection works was selected after the analysis of the technical condition of shaft structures as well as hydrological and geomechanical conditions. Due to the closeness of the shaft lining, it was necessary to form grout columns using jet grouting and low-pressure grouting technologies. The article presents the issues related to the selected technology and its application to the neutralisation of the emergent geotechnical hazard. The method of performance of recommended works was also described together with their impact on the technical condition of structures discussed as well as their functionality and usage.

  12. Sinking blind shaft G272 at the West colliery of RAG by means of an innovative sinking technology

    Energy Technology Data Exchange (ETDEWEB)

    Stenmans, Karl-Heinz [RAG Aktiengesellschaft, Kamp-Lintfort (Germany). West Colliery; Reith, Dietmar [Induberg Produktionsgesellschaft GmbH, Ahlen (Germany)

    2008-08-21

    With the shaft jumbo an innovative sinking technology is being used for the first time in the German coal mining industry. The drilling equipment originating from French shaft sinking was modified to meet the requirements of operation at the West colliery. The equipment is to be used to drill the shot holes and bolt holes for sinking a 535 m blind shaft. The first 50 m have already been sunk, and provides an opportunity to report on the experience so far acquired and describe the further procedure. The work on the site was considerably exacerbated by the inflow of large quantities of water, the impact of which was increased by the upward ventilation in the advance borehole. The new shaft is highly important in the development of the reserves in the Girondelle 5 seam. The specialist mining company Induberg was qualified for this task not least of all because of its references in the field of drivage of mine workings. (orig.)

  13. Design, manufacture and evaluation of a new flexible constant velocity mechanism for transmission of power between parallel shafts

    Energy Technology Data Exchange (ETDEWEB)

    Yaghoubi, Majid [University of Tehran, Tehran (Iran, Islamic Republic of); Sanaeifar, Alireza [Shiraz University, Shiraz (Iran, Islamic Republic of)

    2015-08-15

    This paper presents a new mechanism (coupling) for power transmission between parallel shafts in more ranges. The mechanism consists of one drive shaft and one driven shaft, 3 S-shape transmitter links and 8 connecting links. The advantage of this mechanism is that the velocity ratio between input and output shafts remains constant at all movements, and its capacity to offset misalignments is greater than that of other couplings. This research also includes a kinematic analysis and simulations using Visual NASTRAN, Autodesk inventor dynamic and COSMOS motion to prove that the mechanism exhibits a constant velocity. Finally, the mechanism was fabricated and evaluated; results showed that the mechanism can practically transmit a constant velocity ratio.

  14. Demonstration of Protein-Based Human Identification Using the Hair Shaft Proteome

    Science.gov (United States)

    Leppert, Tami; Anex, Deon S.; Hilmer, Jonathan K.; Matsunami, Nori; Baird, Lisa; Stevens, Jeffery; Parsawar, Krishna; Durbin-Johnson, Blythe P.; Rocke, David M.; Nelson, Chad; Fairbanks, Daniel J.; Wilson, Andrew S.; Rice, Robert H.; Woodward, Scott R.; Bothner, Brian; Hart, Bradley R.; Leppert, Mark

    2016-01-01

    Human identification from biological material is largely dependent on the ability to characterize genetic polymorphisms in DNA. Unfortunately, DNA can degrade in the environment, sometimes below the level at which it can be amplified by PCR. Protein however is chemically more robust than DNA and can persist for longer periods. Protein also contains genetic variation in the form of single amino acid polymorphisms. These can be used to infer the status of non-synonymous single nucleotide polymorphism alleles. To demonstrate this, we used mass spectrometry-based shotgun proteomics to characterize hair shaft proteins in 66 European-American subjects. A total of 596 single nucleotide polymorphism alleles were correctly imputed in 32 loci from 22 genes of subjects’ DNA and directly validated using Sanger sequencing. Estimates of the probability of resulting individual non-synonymous single nucleotide polymorphism allelic profiles in the European population, using the product rule, resulted in a maximum power of discrimination of 1 in 12,500. Imputed non-synonymous single nucleotide polymorphism profiles from European–American subjects were considerably less frequent in the African population (maximum likelihood ratio = 11,000). The converse was true for hair shafts collected from an additional 10 subjects with African ancestry, where some profiles were more frequent in the African population. Genetically variant peptides were also identified in hair shaft datasets from six archaeological skeletal remains (up to 260 years old). This study demonstrates that quantifiable measures of identity discrimination and biogeographic background can be obtained from detecting genetically variant peptides in hair shaft protein, including hair from bioarchaeological contexts. PMID:27603779

  15. Linear force and moment equations for an annular smooth shaft seal perturbed both angularly and laterally

    Science.gov (United States)

    Fenwick, J.; Dijulio, R.; Ek, M. C.; Ehrgott, R.

    1982-01-01

    Coefficients are derived for equations expressing the lateral force and pitching moments associated with both planar translation and angular perturbations from a nominally centered rotating shaft with respect to a stationary seal. The coefficients for the lowest order and first derivative terms emerge as being significant and are of approximately the same order of magnitude as the fundamental coefficients derived by means of Black's equations. Second derivative, shear perturbation, and entrance coefficient variation effects are adjudged to be small.

  16. Shaft Position Influence on Technical Characteristics of Universal Two-Stages Helical Speed Reducers

    OpenAIRE

    Мilan Rackov; Zeljko Kanovic; Sinisa Kuzmanovic; Ruzica Trbojevic

    2005-01-01

    Purchasers of speed reducers decide on buying those reducers, that can the most approximately satisfy their demands with much smaller costs. Amount of used material, ie. mass and dimensions of gear unit influences on gear units price. Mass and dimensions of gear unit, besides output torque, gear unit ratio and efficiency, are the most important parameters of technical characteristics of gear units and their quality. Centre distance and position of shafts have significant influence on output t...

  17. Management of open fractures of the tibial shaft in multiple trauma

    Directory of Open Access Journals (Sweden)

    Stanislaw Boltuc

    2008-01-01

    Full Text Available Background: The work presents the assessment of the results of treatment of open tibial shaft fractures in polytrauma patients. Materials and Methods: The study group comprised 28 patients who underwent surgical treatment of open fractures of the tibial shaft with locked intramedullary nailing. The mean age of the patients was 43 years (range from 19 to 64 years. The criterion for including the patients in the study was concomitant multiple trauma. For the assessment of open tibial fractures, Gustilo classification was used. The most common concomitant multiple trauma included craniocerebral injuries, which were diagnosed in 12 patients. In 14 patients, the surgery was performed within 24 h after the injury. In 14 patients, the surgery was delayed and was performed 8-10 days after the trauma. Results: The assessment of the results at 12 months after the surgery included the following features: time span between the trauma and the surgery and complications in the form of osteomyelitis and delayed union. The efficacy of gait, muscular atrophy, edema of the operated limb and possible disturbances of its axis were also taken under consideration. In patients operated emergently within 24 h after the injury, infected nonunion was observed in three (10.8% males. These patients had grade III open fractures of the tibial shaft according to Gustilo classification. No infectious complications were observed in patients who underwent a delayed operation. Conclusion: Evaluation of patients with open fractures of the tibial shaft in multiple trauma showed that delayed intramedullary nailing performed 8-10 days after the trauma, resulted in good outcome and avoided development of delayed union and infected nonunion. This approach gives time for stabilization of general condition of the patient and identification of pathogens from wound culture.

  18. Modelling and Stability of a Single-Shaft Combined Cycle Power Plant

    Directory of Open Access Journals (Sweden)

    Costas Vournas

    2007-06-01

    Full Text Available The subject of this paper is the development of a dynamic model for a single-shaft combined cycle plant and the analysis of its response to electrical load and frequency transients. In particular the stability of the frequency control, as well as the implications of overheat control are investigated. The model is developed in the Simulink environment of Matlab as part of an educational and research simulation package for autonomous and interconnected systems.

  19. Treatment of Middle Third Humeral Shaft Fractures with Anteromedial Plate Osteosynthesis through an Anterolateral Approach

    Directory of Open Access Journals (Sweden)

    Kumar BS

    2016-03-01

    Full Text Available Background: Treatment of humeral shaft fractures has been a subject of debate for many decades. Even though a large majority of humeral shaft fractures can be treated by non operative methods, few conditions like open fractures, polytrauma, ipsilateral humeral shaft and forearm fractures require surgical intervention. The goal of treatment of humeral shaft fractures is to establish union with an acceptable humeral alignment and to restore the patient to pre-injury level of function. The objective was to assess the incidence of radial nerve palsy, non-union and mean time required for in anteromedial plate osteosynthesis with anterolateral approach and also to measure the functional outcome of this procedure. Method: A prospective study was conducted in the Department of Orthopaedics, PESIMSR, Kuppam, Andhra Pradesh, from August 2012 to August 2015 with a total of 54 patients who were operated with anteromedial plate osteosynthesis were included in the study. RodriguezMerchan criteria was used to grade the functional outcome. Results: Of the 54 patients, 28 (58.85% were in the age group of 30-40 years. The most common fracture pattern identified was A3 type (48.14%.The mean (+ SD duration of surgery for anteromedial humeral plating was 53 ± 5.00 minutes. The time taken for the fracture to unite was less than 16 weeks in the majority or 50 patients (92.59%. Four (7.40% patients had delayed union. There was no incidence of iatrogenic radial nerve palsy. Rodriguez – Merchan criteria showed that 37(68.51% of the patients had good and 12 (22.22% had excellent functional outcome.

  20. Influence of fluid temperature gradient on the flow within the shaft gap of a PLR pump

    Science.gov (United States)

    Qian, W.; Rosic, B.; Zhang, Q.; Khanal, B.

    2016-03-01

    In nuclear power plants the primary-loop recirculation (PLR) pump circulates the high temperature/high-pressure coolant in order to remove the thermal energy generated within the reactor. The pump is sealed using the cold purge flow in the shaft seal gap between the rotating shaft and stationary casing, where different forms of Taylor-Couette flow instabilities develop. Due to the temperature difference between the hot recirculating water and the cold purge water (of order of 200 °C), the flow instabilities in the gap cause temperature fluctuations, which can lead to shaft or casing thermal fatigue cracks. The present work numerically investigated the influence of temperature difference and rotating speed on the structure and dynamics of the Taylor-Couette flow instabilities. The CFD solver used in this study was extensively validated against the experimental data published in the open literature. Influence of temperature difference on the fluid dynamics of Taylor vortices was investigated in this study. With large temperature difference, the structure of the Taylor vortices is greatly stretched at the interface region between the annulus gap and the lower recirculating cavity. Higher temperature difference and rotating speed induce lower fluctuating frequency and smaller circumferential wave number of Taylor vortices. However, the azimuthal wave speed remains unchanged with all the cases tested. The predicted axial location of the maximum temperature fluctuation on the shaft is in a good agreement with the experimental data, identifying the region potentially affected by the thermal fatigue. The physical understandings of such flow instabilities presented in this paper would be useful for future PLR pump design optimization.

  1. Shafting Alignment Calculation Based on APDL%基于APDL的轴系校中计算

    Institute of Scientific and Technical Information of China (English)

    张兴涛; 蒋岚岚

    2012-01-01

    本文介绍了轴系合理校中的必要性以及基于APDL的校中计算方法,并通过对比计算结果,说明该计算方法是完全适用的。%This paper introduces the necessity of shafting alignment and the calculation method based on APDL. By comparing the calculation results, it is proved that the method is completely applicable.

  2. Gearbox Reliability Collaborative Investigation of High-Speed-Shaft Bearing Loads

    Energy Technology Data Exchange (ETDEWEB)

    Keller, Jonathan [National Renewable Energy Lab. (NREL), Golden, CO (United States); Guo, Yi [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2016-06-01

    The loads and contact stresses in the bearings of the high speed shaft section of the Gearbox Reliability Collaborative gearbox are examined in this paper. The loads were measured though strain gauges installed on the bearing outer races during dynamometer testing of the gearbox. Loads and stresses were also predicted with a simple analytical model and higher-fidelity commercial models. The experimental data compared favorably to each model, and bearing stresses were below thresholds for contact fatigue and axial cracking.

  3. INTERNAL FRICTION OF 51CrV4 SHAFT INFLUENCED BY THERMO-MECHANICAL COUPLING

    Institute of Scientific and Technical Information of China (English)

    J. G(o)ken; M. Maikranz-Valentin; K. Steinhoff; T.S. Pavlova; T.V. Ivleva; I.S. Golovin

    2008-01-01

    The simultaneous influence of thermal and mechanical treatment was applied to produce a geometrically complex shaft from 51CrV4 steel leading to the formation of microstructures which were significantly different from each other. These microstructural differences were accompanied by a local change of mechanical properties in terms of hardness, electrical resistivity and especially internal friction. The Snoek-Koster peak was recognized and analyzed in the structure of this steel.

  4. COMPARISON OF PNEUMATIC FLEXIBLE SHAFT COUPLING STATIC LOAD CHARACTERISTICS OBTAINED EXPERIMENTALLY AND BY CALCULATION

    Directory of Open Access Journals (Sweden)

    Peter KAŠŠAY

    2014-12-01

    Full Text Available Pneumatic flexible shaft couplings allow the change of their stiffness by the pressure change of gaseous medium in their pneumatic flexible elements, allowing their use as a device for continuous tuning of torsional oscillating mechanical systems directly during operation. The aim of this paper is to verify the accuracy of compression volume modeling method on existing pneumatic flexible coupling, by comparison of static load characteristics obtained experimentally with characteristics calculated from mathematical and physical model.

  5. Effect of rain boot shaft length on lower extremity muscle activity during treadmill walking

    Science.gov (United States)

    Kim, Young-Hwan; Yoo, Kyung-Tae

    2016-01-01

    [Purpose] This study aimed to determine the extent of lower extremity muscle activity before and after walking based on rain boot shaft length. [Subjects and Methods] The subjects, 12 young and healthy females, were divided into three groups based on rain boot shaft length (long, middle, and short). They walked on a treadmill for 30 minutes. Activity of the rectus femoris, vastus lateralis, semitendinosus, tibialis anterior, peroneus longus, and gastrocnemius was measured using electromyography before and after walking. Two-way repeated measures analysis of variance was performed to compare the muscle activities of each group. [Results] There were no significant differences in terms of the interactive effects between group and time for all muscles, the main effects of group, or the main effects of time. [Conclusion] The results of this study may indicate that movement of the lower extremities was not significantly limited by friction force based on the characteristics of the boot material or the circumference of the boot shaft. Thus, it may be helpful instead to consider the material of the sole or the weight of the boots when choosing which rain boots to wear. PMID:27799685

  6. An adaptive turbo-shaft engine modeling method based on PS and MRR-LSSVR algorithms

    Institute of Scientific and Technical Information of China (English)

    Wang Jiankang; Zhang Haibo; Yan Changkai; Duan Shujing; Huang Xianghua

    2013-01-01

    In order to establish an adaptive turbo-shaft engine model with high accuracy,a new modeling method based on parameter selection (PS) algorithm and multi-input multi-output recursive reduced least square support vector regression (MRR-LSSVR) machine is proposed.Firstly,the PS algorithm is designed to choose the most reasonable inputs of the adaptive module.During this process,a wrapper criterion based on least square support vector regression (LSSVR) machine is adopted,which can not only reduce computational complexity but also enhance generalization performance.Secondly,with the input variables determined by the PS algorithm,a mapping model of engine parameter estimation is trained off-line using MRR-LSSVR,which has a satisfying accuracy within 5‰.Finally,based on a numerical simulation platform of an integrated helicopter/turbo-shaft engine system,an adaptive turbo-shaft engine model is developed and tested in a certain flight envelope.Under the condition of single or multiple engine components being degraded,many simulation experiments are carried out,and the simulation results show the effectiveness and validity of the proposed adaptive modeling method.

  7. Comparison of minimally invasive plate osteosynthesis and conventional plate osteosynthesis for humeral shaft fracture

    Science.gov (United States)

    Yu, Bin-feng; Liu, Liang-le; Yang, Guo-jing; Zhang, Lei; Lin, Xi-peng

    2016-01-01

    Abstract Background: The objective of this meta-analysis was to compare the efficacy and safety of minimally invasive plate osteosynthesis (MIPO) and conventional plate osteosynthesis (CPO) for humeral shaft fracture. Methods: Potential academic articles were identified from the Cochrane Library, Medline (1966–2016.3), PubMed (1966–2016.3), Embase (1980–2016.3), and ScienceDirect (1966–2016.3). Gray studies were identified from the references of the included literature. Randomized controlled trials (RCTs) and non-RCT involving MIPO and CPO for humeral shaft fracture were included. Two independent reviewers performed independent data abstraction. I2 statistic was used to assess heterogeneity. Fixed or random effects model was used for meta-analysis. Results: Two RCTs and 3 non-RCTs met the inclusion criteria. There was a lower incidence of iatrogenic radial nerve palsy in patients with MIPO (P = 0.006). There was no statistically significant difference in in the risk of developing nonunion, delay union, malformation, screw loosening, infection, operation time, UCLA, and MEPS function score between the 2 groups. Conclusion: MIPO decreased incidence of iatrogenic radial nerve palsy and is an efficacy and safety technique for humeral shaft fracture. Due to the limited quality and data of the evidence currently available, more high-quality RCTs are required. PMID:27684839

  8. Atypical subtrochanteric and femoral shaft fractures and possible association with bisphosphonates.

    Science.gov (United States)

    Nieves, Jeri W; Cosman, Felicia

    2010-03-01

    Several case series and multiple individual case reports suggest that some subtrochanteric and femoral shaft fractures might occur in patients who have been treated with long-term bisphosphonates. Several unique clinical and radiographic features are emerging: prodromal thigh pain prior to the fracture, complete absence of trauma precipitating the fracture, and bilateral fractures in some patients. Radiographic features include presence of stress reaction, transverse or short oblique fractures, and thick femoral cortices. The overall incidence of subtrochanteric and shaft fractures combined is below 30 per 100,000 person-years, so this type of fracture is much less common than proximal femur (hip) fracture. Furthermore, the unique "atypical" fracture type is a subset of all subtrochanteric and femoral shaft fractures. The putative mechanism is unknown, and more research is needed to identify distinctive characteristics and the pathophysiology of these atypical fractures. There is no rationale to withhold bisphosphonate therapy from patients with osteoporosis, although continued use of bisphosphonate therapy beyond a treatment period of 3 to 5 years should be re-evaluated annually.

  9. Mobility factors of cracked ore in vibrating-ore draw shafts

    Institute of Scientific and Technical Information of China (English)

    WU Ai-xiang; JIANG Li-chun; CHEN Jia-sheng

    2005-01-01

    The mobile factors of cracked ore in vibrating-ore draw shafts were analyzed. The results show that the mobile coefficient of cracked ores will be mainly influenced by the combination of ore physical factors if the structure dimension and parameters of vibrating ore-draw shafts are sure. It decreases with increasing the cohesion, lump content, lump size and powder content and increases with increasing the porosity. The coefficient decreases with increasing the moisture content, but increases after the moisture content reaches a certain value. Uniform grain leads to better mobility, non-uniform grain leads to worse mobility. The value of the mobile coefficient should be in a range of 0.31.1 when designing the vibrating ore-draw shafts. According to correlation degree of grey system theory, the effects of factors on the mobility of cracked ore are given in the weight decreasing consequence as follows: moisture content, lump content, distribution of grain size, lump size, porosity, cohesion and powder ore content. It is unreasonable to neglect any one because the values of their weights are not obvious.

  10. Human hair shaft proteomic profiling: individual differences, site specificity and cuticle analysis

    Directory of Open Access Journals (Sweden)

    Chelsea N. Laatsch

    2014-08-01

    Full Text Available Hair from different individuals can be distinguished by physical properties. Although some data exist on other species, examination of the individual molecular differences within the human hair shaft has not been thoroughly investigated. Shotgun proteomic analysis revealed considerable variation in profile among samples from Caucasian, African–American, Kenyan and Korean subjects. Within these ethnic groups, prominent keratin proteins served to distinguish individual profiles. Differences between ethnic groups, less marked, relied to a large extent on levels of keratin associated proteins. In samples from Caucasian subjects, hair shafts from axillary, beard, pubic and scalp regions exhibited distinguishable profiles, with the last being most different from the others. Finally, the profile of isolated hair cuticle cells was distinguished from that of total hair shaft by levels of more than 20 proteins, the majority of which were prominent keratins. The cuticle also exhibited relatively high levels of epidermal transglutaminase (TGM3, accounting for its observed low degree of protein extraction by denaturants. In addition to providing insight into hair structure, present findings may lead to improvements in differentiating hair from various ethnic origins and offer an approach to extending use of hair in crime scene evidence for distinguishing among individuals.

  11. Generalized solution of design optimization and failure analysis of composite drive shaft

    Energy Technology Data Exchange (ETDEWEB)

    Kollipalli, K.; Shivaramakrishna, K.V.S.; Prabhakaran, R.T.D. [Birla Institute of Technology and Science, Goa (India)

    2012-07-01

    Composites have an edge over conventional metals like steel and aluminum due to higher stiffness-to-weight ratio and strength-to-weight ratio. Due to these advantages, composites can bring out a revolutionary change in materials used in automotive engineering, as weight savings has positive impacts on other attributes like fuel economy and possible noise, vibration and harshness (NVH). In this paper, the drive line system of an automotive system is targeted for use of composites by keeping constraints in view such as such as torque transmission, torsional buckling load and fundamental natural frequency. Composite drive shafts made of three different composites ('HM Carbon/HS Carbon/E-glass'-epoxy) was modeled using Catia V5R16 CPD workbench and a finite element analysis with boundary conditions, fiber orientation and stacking sequence was performed using ANSYS Composite module. Results obtained were compared to theoretical results and were found to be accurate and in the limits. This paper also speaks on drive shaft modeling and analysis generalization i.e., changes in stacking sequence in the future can be incorporated directly into ANSYS model without modeling it again in Catia. Hence the base model and analysis method made up in this analysis generalization facilitated by CAD/CAE can be used to carry out any composite shaft design optimization process. (Author)

  12. Numerical Study on Pressure Drop Factor in the Vent-Cap of CDQ Shaft

    Institute of Scientific and Technical Information of China (English)

    Bo Song; Yanhui Feng; Xinxin Zhang

    2008-01-01

    In CDQ (Coke Dry Quenching) shaft, the vent-cap with complex structure is installed in the cone-shaped funnel under the cooling chamber. It acts to introduce cooling gas and support the descending coke in the chamber. The designing and installation of vent-cap aim to get relatively uniform gas distribution, to reduce the temperature fluctuation of cokes at outlet and realize stable operation of CDQ apparatus. In this paper, the turbulent flow of gas in vent-cap of 1:7 scale CDQ experimental shaft is numerically simulated by using CFD (Computational Fluid Dynamics) software, CFX. The velocity field, the outlet flux distribution and the pressure drop factor of each outlet under three kinds of vent-cap (called high vent-cap, low vent-cap and elliptic vent-cap) are analysed and compared. The results turn out that the pressure drop factor of elliptic vent-cap is larger than the other two vent-caps, and that the pressure drop factors of high vent-cap and low vent-cap almost have the same value.While for a specified vent-cap, the pressure drop factor with pressing brick is larger than that without pressing brick. The work in this paper is valuable for the designing of vent-cap for large-acale CDQ shaft.

  13. A CLINICAL STUDY OF FIXATION O FRACTURE OF SHAFT OF HUMERUS WITH INTERLOCKING NAIL

    Directory of Open Access Journals (Sweden)

    Jayachandra Reddy

    2015-02-01

    Full Text Available the aim of the present study is to evaluate the results of closed interlocking intramedullary nail in the management of fractures of shaft humerus.20 humeral shaft fractures were treated by closed reduction and intramedullary interlocking nailing in the department of orthopaedics , government medical college , government general hospital , anantapuramu from November 2010 to A ug 2012. The cause of fracture was RTA in 17 cases and fall in 3 cas es. Age incidence varied from 20 years to 60 years , 14 were male 6 female. Out of 20 cases in 18 cases fracture united by 3 to 4 months. 2 non - unions occurred after 6 months. , Excellent results were obtained in 40% of the cases , good results in 20%of the cases , fair results in 25% and Poor results in 15% of the cases. M ost common complication was shoulder stiffness occurring in 5 cases. W e conclude that interlocking nailing for humerus shaft fractures is an effective means of fixation. T he most common complication is shoulder stiffness which can be minimized by preventing proximal protrusion of nail , proper repair of rotator cuff and early rehabilitation.

  14. CONTROLLING SMALL MOVEMENTS OF ULTRA PRECISE DC ELECTRIC DRIVE WITH ELASTIC SHAFTING

    Directory of Open Access Journals (Sweden)

    Dobrobaba Y. P.

    2015-10-01

    Full Text Available Control of the movement and positioning are the most intensive tasks of automatic control and regulation. However, these problems must be solved in the automation objects such as assembly and production lines, manufacturing machines, conveyors, hoisting machines, packaging machines, filling lines for liquids, metal-working machines. One problem lies in the fact that all the real drives are connected to the actuators with not perfectly tough shafting, but has some elasticity. This leads to the difficulty of motion of the executive body of the drive automatic control systems which consists of signal source generating signal due optimum speed diagrams for small movements of electric drive’s actuating device and automatic regulation system, which allows to work out optimum speed diagrams for small movements of electric drive’s actuating device with ultra-precision. In this article were developed optimum speed diagram for small movements of ultra-precise electric drive with elastic shafting. Were have identified all parameters of diagrams and its range of existence and also developed a device for generating the optimum speed diagram for small movements of ultra-precise electric drive with elastic shafting. The implementation of the proposed hardware software complex will significantly improve the accuracy of motion actuators of various ultra- precise DC drives

  15. CONTROL OF MEDIUM MOVEMENTS OF ULTRA PRECISE DC ELECTRIC DRIVE WITH ELASTIC SHAFTING

    Directory of Open Access Journals (Sweden)

    Dobrobaba Y. P.

    2015-12-01

    Full Text Available Control of the movement and positioning are the most intensive tasks of automatic control and regulation. However, these problems must be solved in the automation objects such as assembly and production lines, manufacturing machines, conveyors, hoisting machines, packaging machines, filling lines for liquids, metal-working machines. One problem lies in the fact that all the real drives are connected to the actuators with not perfectly tough shafting, but has some elasticity. This leads to the difficulty of motion of the executive body of the drive automatic control systems which consists of signal source generating signal due optimum speed diagrams for medium movements of electric drive’s actuating device and automatic regulation system, which allows to work out optimum speed diagrams for medium movements of electric drive’s actuating device with ultra-precision. In this article were developed optimum speed diagram for medium movements of ultra-precise electric drive with elastic shafting. Were identified all parameters of diagrams and its range of existence. Also developed device for generating the optimum speed diagram for medium movements of ultra-precise electric drive with elastic shafting. Implementation of the proposed hardware software complex will significantly improve the accuracy of motion actuators of various ultra- precise DC drives

  16. Construction Method of Coal Bunker in Vertical Shaft%立井煤仓施工法

    Institute of Scientific and Technical Information of China (English)

    周乐平

    2014-01-01

    Coal bunker construction is difficult in the cavern of a project ,in which raised -shaft method-concrete support is frequently applied under the conditions of stable strata at workface without gas and water gushing . Taking the 300-meter coal bunker with No .2 belt in Xianting Colliery as an example ,the author expounds the application of general raised -shaft method in the construction of coal bunker in vertical shaft under certain con-ditions ,which provides the reference for similar roadway construction .%煤仓是煤矿硐室中施工难度较大的一项工程,在工作面岩层稳定、无瓦斯和涌水的情况下,施工直立式煤仓多采用普通反井法---混凝土支护。本文以仙亭煤矿2#皮带+300 m煤仓为例阐述了普通反井法在特定条件下立井煤仓中的应用,为该类巷道施工提供经验借鉴。

  17. Influence of pre-load coefficient of TPJBs with even number pads on shaft lateral vibration

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    For a rotating machine with one or more tilting pad journal bearings (TPJBs), it is acommon state that pad-to-journal assembling clearances are uneven in one bearing, or inconsis-tent relationship of assembling clearances are encountered among all the bearings. Consideringthe structural characteristics of a TPJB, a concept named as "pad pair pre-load coefficient" corre-sponding to bearing pre-load coefficient is proposed. Firstly, the influence of bearing pre-load coef-ficient and pad pair pre-load coefficient on shaft vibration in a Jeffcot rotor is analyzed. Then takingNo.1 unit with two TPJBs in Guangzhou pumped storage power plant (GPSP) as an example, theinfluence of inconsistent relationship of the two bearing pre-load coefficients on shaft vibration isanalyzed. The results show that variety of one bearing pre-load coefficient will only influence vibra-tion amplitude, not involving the shape of shaft center orbit. But variety of one or more "pad pairpre-load coefficient" will influence not only vibration amplitude, but also the shape of orbit-whichwill be turned from a circle to an ellipse. By investigating variation characteristics of shape andvibration amplitude of orbits at the TPJBs, some theoretical bases will be supplied for diagnosingthe condition of the unit bearings.

  18. Compaction and stressing - a new stabilisation concept for deep shafts; Verdichten und Verspannen - ein neuartiges Sicherungskonzept fuer tiefe Schaechte

    Energy Technology Data Exchange (ETDEWEB)

    Daude, E.; Ossenbuehl, I. [Gebhardt und Koenig Berg- und Bautechnik GmbH, Recklinghausen (Germany); Scherbeck, R. [TABERG Ingenieure GmbH, Luenen (Germany)

    2006-10-23

    Placing Bullflex-geotextiles in boreholes from ground level is part of a new stabilization technique for deep old shafts filled up with non cohesive materials. Bullflex-elements increase the material's density when filled with cement-based grout under pressure by radial movements of the fill material. The global stability of an old shaft can be analyzed easily when relying on results from Bullflex installations actually proved by measurements. (orig.)

  19. Analysis of fatigue transverse cracks in turbine shafts; Analyse des fissures transverses de fatigue dans les arbres de turbines

    Energy Technology Data Exchange (ETDEWEB)

    Aubry, P. [Alstom Power, service client, 93 - Stains (France); Cailleaux, J.P. [Electricite de France (EDF), Pole Industrie Div. Production Nucleaire, 93 - Saint-Denis (France)

    2001-07-01

    During a safety control of the low pressure turbines CP0/CP1 shafts, some transverse cracks have been identified. In a first step, the crack propagation has been studied by the following three actions: improvement of the control methods, material characterization to calculate the crack propagation threshold taking into account the operating conditions, a 3-D numerical analysis of the shaft solicitations with the calculation of KI KII KIII for the crack propagation estimation. (A.L.B.)

  20. Studies of the quality and cost-effectiveness of a novel conceptof open-die forged powerplant main shaft

    Directory of Open Access Journals (Sweden)

    P. Skubisz

    2015-04-01

    Full Text Available An innovatory concept of open-die forging of windmill main shaft is described. Comparative study of the new technology based on the concept of cogging hollow shaft on mandrel featuring material savings and higher quality of a finished part versus traditional production chain of this component is presented, indicating benefits and technological setbacks of industrial implementation. Results of industrial sampling aided with numerical simulation form guidelines for technological realization.

  1. Nickel-Titanium swan-like memory connector:a new tool to treat humeral shaft nonunion

    Institute of Scientific and Technical Information of China (English)

    沈洪兴; 张春才; 许硕贵; 王家林

    2004-01-01

    Objective: To explore a new strategy to treat humeral shaft nonunion efficiently. Methods: In the light of mechanical characteristics of Nickel-Titanium memory and the anatomic morphology of humeral shaft, we designed the swan-like shape memory alloy connector (SMC). SMC was clinically applied in treating 55 cases of humeral shaft nonunion. Success rate of nonunion repair, reinterventions, complications, range of motion, and patient satisfaction were evaluated. Results: Fifty-five humeral shaft nonunion patients were treated with autogenous bone grafting and SMC internal fixation. The average follow-up period was 32 months. In 50 patients with complete follow-up data, 49 were recovered from nonunion by lamellar bone healing. The excellent and good rate was 98%; one patient suffering from re-fracture in a fall refused further treatment. Neither infection nor re-fracture after SMC extraction or joint dysfunction was found in the whole group. Conclusion: SMC facilitates safe internal fixation and bone grafting; its memory biomechanic properties promote osteosynthesis, resulting in accelerated and high quality healing of humeral shaft nonunion. SMC internal fixation with bone grafting is creative, efficient and promising in treating humeral shaft nonunion.

  2. INVESTIGATION OF MECHANICAL STRESSES IN THE DRIVE SHAFT OF MV VACUUM CIRCUIT BREAKER

    Directory of Open Access Journals (Sweden)

    E. I. Baida

    2017-03-01

    Full Text Available Introduction. In the last 10-15 years a dominant position in the market of medium voltage circuit breakers, vacuum circuit breakers have taken in which as an actuator mono- or bistable actuators with permanent magnets are used. Such circuit breakers are characterized by simplicity of design, high reliability, require preventive maintenance for many years. Development, research and improvement of vacuum circuit breakers are carried out at the Department for Electrical Apparatus, National Technical University «Kharkiv Polytechnic Institute». While working on the circuit breakers, developers have to deal with two related objectives – electrical and mechanical. This paper considers the solution of one of these problems – calculation of mechanical forces in the drive shaft of the vacuum circuit breaker in static and dynamic modes. This work was preceded by the failure of the results of measurements of the prototype circuit breakers’ contacts. Measurements have shown that these values do not match the expected values (there were less than the value of 0.8 to 1 mm. The assumption about the reasons for this discrepancy needed to be detailed checked. The results of the work done are presented in this paper. Purpose. Investigation of static and dynamic mechanical stresses and strains in the drive shaft of the vacuum circuit breaker mechanism to determine its characteristics and material selection. Methods. The investigation of mechanical processes is performed by the finite element method in the COMSOL software package. Results. We obtain the static and dynamic characteristics of the circuit breaker drive shaft: deformations, reaction forces, stresses. These characteristics made it possible to determine the actual course of the contacts, select shaft material and calculate the forces acting on the bearings. Conclusions. It is shown that the contact velocity and contact pressure are different from the theoretical value due to the deformation of the

  3. Biomechanical Study of the Fixation Strength of Anteromedial Plating for Humeral Shaft Fractures

    Institute of Scientific and Technical Information of China (English)

    Yin-Feng Zheng; Jun-Lin Zhou; Xiao-Hong Wang; Lei Shan; Yang Liu

    2016-01-01

    Background:Open reduction and internal fixation with plate and screws are the gold standard for the surgical treatment of humeral shaft fractures,this study was to compare the mechanical properties of anteromedial,anterolateral,and posterior plating for humeral shaft fractures.Methods:A distal third humeral shaft fracture model was constructed using fourth-generation sawbones (#3404,composite bone).Atotal of 24 sawbones with a distal third humeral shaft fracture was randomly divided into three Groups:A,B,and C (n =8 in each group) for anteromedial,anterolateral,and posterior plating,respectively.All sawbones were subjected to horizontal torsional fatigue tests,horizontal torsional and axial compressive fatigue tests,four-point bending fatigue tests in anteroposterior (AP) and mediolateral (ML) directions and horizontal torsional destructive tests.Results:In the horizontal torsional fatigue tests,the mean torsional angle amplitude in Groups A,B,and C were 6.12°,6.53°,and 6.81°.In horizontal torsional and axial compressive fatigue tests,the mean torsional angle amplitude in Groups A,B,and C were 5.66°,5.67°,and 6.36°.The mean plate displacement amplitude was 0.05 mm,0.08 mm,and 0.10 mm.Group A was smaller than Group C (P < 0.05).In AP four-point bending fatigue tests,the mean plate displacement amplitude was 0.16 mm,0.13 mm,and 0.20 mm.Group B was smaller than Group C (P < 0.05).In ML four-point bending fatigue tests,the mean plate displacement amplitude were 0.16 mm,0.19 mm,and 0.17 mm.In horizontal torsional destructive tests,the mean torsional rigidity in Groups A,B,and C was 0.82,0.75,and 0.76 N.m/deg.The yielding torsional angle was 24.50°,25.70°,and 23.86°.The mean yielding torque was 18.46,18.05,and 16.83 N·m,respectively.Conclusions:Anteromedial plating was superior to anterolateral or posterior plating in all mechanical tests except in AP four-point bending fatigue tests compared to the anterolateral plating group.We can suggest that

  4. Vibration instability of laser base and atmospheric refraction in the process of aligning and operational control of underground mine shafts: effects and methods of mitigation

    Science.gov (United States)

    Passia, Henryk; Szade, Adam; Motyka, Zbigniew; Bochenek, Wojciech; Lipowczan, Adam

    2004-06-01

    Reliable operation of underground mine shafts is strongly conditioned by the proper position of the shaft frame and the installations inside the shaft tube in relation to the vertical direction. For operational reasons and safety, they are subject to periodical control and emergency control in the case when the permissible values of the operational parameters are likely to be exceeded. These can be, for instance, the values of tilt of the shaft frame or of the irregularity of the bars which guide the conveyance (i.e. cage or skip) in the shaft. One of the reasons of such a situation to occur can be the movement of the ground in the closer or farther proximity of the shaft, as a consequence of the effects of mining, hydro-geological changes in the ground, etc.

  5. STUDY ON EFFECTS TO SHAFT WALL DEFORMATIONS AND FAILURES INDUCED BY LAYER'S CONSOLIDATION DUE TO WATER WTI~HDRAWAL OF EXTRA-THICK UNCONSOLIDATED AQUIFERS

    Institute of Scientific and Technical Information of China (English)

    GENGDeyong; XUYanchun; SHENBaohong

    1995-01-01

    Accordance with more than 10 shaft wall deformation and failure events in Huang-Huai regions in the east of China, this paper discusses effects to shaft wall deformations and failures induced by layer's consolidation due to water withdrawal of extra-thick unconsolidated aquifers and its further deformation or damage trends, based on data obtained from simultaneous monitoring of both damaged and undamaged shafts, their correspondent unconsolidated layers and atmospheric precipitation etc.for more then 3 years.

  6. Modeling of shaft tombs in western Mexico by mean of resistive tomography

    Science.gov (United States)

    Alatorre-Zamora, M. A.; Gutierrez-Peña, Q. J.; Gomez-Gomez, G.; Rosas-Elguera, J.

    2013-05-01

    The archaeological affluence of Mexico is huge. However, the western part of the country is viewed as lacking of important prehispanic constructions. Discoveries since 1970 have exposed an ancient culture that has been termed as Teuchitlan Tradition. This culture is characterized by ceremonial centers formed with circular pyramids and several rectangular platforms surrounding them, and tombs below any of these structures. The tombs in turn are typically composed of a vertical shaft and one to three horizontal chambers, where bodies were placed. Due to this character is also referred to as Shaft Tombs Culture. The tombs are located mainly in low cohesion pumice, welded tephras and volcanic ash deposits. The vertical shafts were usually filled, and there was always the camera. Two major centers developed by this culture are found in Teuchitlan and El Arenal, in the western state of Jalisco. The former has been rebuilt and is currently open to tourism, while the latter is not restored yet. The latter apparently has two ceremonial centers located at two different altitudes. We conducted a survey in both sites with resistive tomography. The first study was conducted in Teuchitlan, on a circular platform. In this structure there are already located three shaft tombs. The results obtained using the Wenner alpha array with equidistance of 0.5 and 1 meter, are successful. The data have been modeled using the program RES2DINV, and models obtained show the presence of a boot-shaped tomb and other like bottle. The graves are identified with higher resistivity values, while values lower than 30 ohm-m indicate moisture leaks at the ends of the structure. Theoretical modeling of the tombs and the building was carried out, which is compared with the actual sections and their inversion models. Coincidences are appreciable. With this results, were conducted two lines in ceremonial centers of El Arenal, to identify the occurrence of shaft tombs. The two centers are separated by

  7. Internal derangement of the knee after ipsilateral femoral shaft fracture: MR imaging findings

    Energy Technology Data Exchange (ETDEWEB)

    Blacksin, M.F.; Zurlo, J.V. [Department of Radiology, University of Medicine and Dentistry of New Jersey, Newark, NJ (United States); Levy, A.S. [Department of Orthopedic Surgery, University of Medicine and Dentistry of New Jersey, University Hospital, Newark, NJ 07103-2426 (United States)

    1998-08-01

    Objective. This study uses magnetic resonance (MR) imaging to delineate the types and frequencies of injuries seen in the knee after ipsilateral femoral shaft fracture. We also compare the results of the orthopedic knee examination with the MR findings. Design and patients. MR imaging of the ipsilateral knee was performed on 34 patients with closed femoral shaft fractures. Indications for knee MR imaging included knee pain at the time of fracture, soft tissue swelling or an effusion of the knee, or a positive knee examination under anesthesia. The patients had a mean age of 27 years and all were stabilized with intramedullary nails. Imaging was performed a mean time of 2.5 days after surgery. All patients had knee examinations done under anesthesia, and the MR results were compiled and compared with the clinical examinations. Results. Ninety-seven percent of patients demonstrated knee effusions. Twenty-seven percent of patients demonstrated meniscal tears, with the posterior horn of the medial meniscus most frequently torn. The medial collateral ligament was the most frequent site of ligamentous injury (38%) followed by the posterior cruciate ligament (21%). Fifty percent of patients had injuries of the extensor mechanism. Bone bruises were noted in 32% of patients. Articular cartilage injuries were confined to the patella in four cases. One occult tibial plateau fracture and one meniscocapsular separation were seen. Conclusions. There is a common incidence of both ligamentous and meniscal injury to the knee after ipsilateral femoral shaft fracture. MR imaging can be useful in assessing the extent of injury, and may reveal findings unsuspected after clinical examination of the knee. (orig.) With 4 figs., 2 tabs., 13 refs.

  8. Changes in the Serum Level of Vitamin D During Healing of Tibial and Femoral Shaft Fractures

    Directory of Open Access Journals (Sweden)

    Ettehad

    2014-01-01

    Full Text Available Background: Several systemic factors and hormones are thought to regulate the fracture healing process. Vitamin D has emerged as a compound or hormone that actively participates in the regulation of calcium homeostasis and bone metabolism. Objectives: The aim of this study is to determine the serum changes in the level of vitamin D during the acute healing period of tibial and femoral shaft fractures. Patients and Methods: This cross-sectional study included of 73 patients with tibial and femoral shaft fractures referred to the Poursina Hospital between February 2011 and February 2012. Changes in the serum levels of vitamin D were assessed three times in a period of three weeks (at the first visit, end of first week, and end of the third week. Variables such as age, gender, fractured bone, concomitant fracture of tibia and fibula, type of fracture, time of measurement and serum levels of 25-hydroxyvitamin D were assessed. All statistical analyses were performed using the SPSS software. Results: Forty tibial fractures and 33 femoral fractures were recorded. Mean vitamin D levels at the time of admission, after one week and at the end of the third week for the 73 participants included in the study were 39.23, 31.49, and 28.57 ng/mL, respectively. The overall reduction of vitamin D level was significantly more evident in the first week versus the following (P < 0.0001. Conclusions: Serum levels of vitamin D in patients with tibial or femoral fractures were reduced during the curative period of the fracture. This can be related the role of vitamin D in the formation and mineralization of the callus. Patients with tibial or femoral shaft fractures may benefit from the administration of vitamin D supplements during the fracture healing process.

  9. Mechanism of ad5 vaccine immunity and toxicity: fiber shaft targeting of dendritic cells.

    Directory of Open Access Journals (Sweden)

    Cheng Cheng

    2007-02-01

    Full Text Available Recombinant adenoviral (rAd vectors elicit potent cellular and humoral immune responses and show promise as vaccines for HIV-1, Ebola virus, tuberculosis, malaria, and other infections. These vectors are now widely used and have been generally well tolerated in vaccine and gene therapy clinical trials, with many thousands of people exposed. At the same time, dose-limiting adverse responses have been observed, including transient low-grade fevers and a prior human gene therapy fatality, after systemic high-dose recombinant adenovirus serotype 5 (rAd5 vector administration in a human gene therapy trial. The mechanism responsible for these effects is poorly understood. Here, we define the mechanism by which Ad5 targets immune cells that stimulate adaptive immunity. rAd5 tropism for dendritic cells (DCs was independent of the coxsackievirus and adenovirus receptor (CAR, its primary receptor or the secondary integrin RGD receptor, and was mediated instead by a heparin-sensitive receptor recognized by a distinct segment of the Ad5 fiber, the shaft. rAd vectors with CAR and RGD mutations did not infect a variety of epithelial and fibroblast cell types but retained their ability to transfect several DC types and stimulated adaptive immune responses in mice. Notably, the pyrogenic response to the administration of rAd5 also localized to the shaft region, suggesting that this interaction elicits both protective immunity and vector-induced fevers. The ability of replication-defective rAd5 viruses to elicit potent immune responses is mediated by a heparin-sensitive receptor that interacts with the Ad5 fiber shaft. Mutant CAR and RGD rAd vectors target several DC and mononuclear subsets and induce both adaptive immunity and toxicity. Understanding of these interactions facilitates the development of vectors that target DCs through alternative receptors that can improve safety while retaining the immunogenicity of rAd vaccines.

  10. Limited open reduction is better for simple- distal tibial shaft fractures than minimally invasive plate osteosynthesis.

    Science.gov (United States)

    Li, Q; Zeng, B F; Luo, C F; Song, S; Zhang, C Q; Kong, W Q

    2014-07-24

    The aim of this study was to compare the effects and indications of minimally invasive plate osteosynthesis (MIPO) and limited open reduction (LOR) for managing distal tibial shaft fractures. A total of 79 cases of distal tibial shaft fractures were treated surgically in our trauma center. The 79 fracture cases were classified into type A, B, and C (C1) according to the Arbeitsgemeinschaft für Osteosynthesefragen (AO) classification, with 28, 32, and 19 cases, respectively. Among the 79 fracture cases, 52 were closed fractures and 27 were open fractures (GUSTILO, I-II). After adequate preparation, 48 cases were treated with LOR and 31 cases were treated with MIPO. All cases were followed up for 12 to 18 months, with an average of 16.4 months. During the follow-up period, 76 fracture cases were healed in the first stage, whereas the 3 cases that developed non-union were treated by changing the fixation device and autografting. For types A, B, and some of C simple fractures (C1), LOR accelerated the fracture healing and lowered the non-union rate. One case suffered from regional soft tissue infection, which was controlled by wound dressing and intravenous antibiotics. Another case that developed local skin necrosis underwent local flap transplant. LOR promoted bone healing and lowered the non-union rate of several simple-distal tibial shaft fractures. Thereafter, the incidence of soft tissue complication was not significantly increased. However, for complex and comminuted fractures, MIPO was the preferred method for correcting bone alignment and protecting soft tissue, leading to functional recovery.

  11. Infant bone age estimation based on fibular shaft length: model development and clinical validation

    Energy Technology Data Exchange (ETDEWEB)

    Tsai, Andy; Stamoulis, Catherine; Bixby, Sarah D.; Breen, Micheal A.; Connolly, Susan A.; Kleinman, Paul K. [Boston Children' s Hospital, Harvard Medical School, Department of Radiology, Boston, MA (United States)

    2016-03-15

    Bone age in infants (<1 year old) is generally estimated using hand/wrist or knee radiographs, or by counting ossification centers. The accuracy and reproducibility of these techniques are largely unknown. To develop and validate an infant bone age estimation technique using fibular shaft length and compare it to conventional methods. We retrospectively reviewed negative skeletal surveys of 247 term-born low-risk-of-abuse infants (no persistent child protection team concerns) from July 2005 to February 2013, and randomized them into two datasets: (1) model development (n = 123) and (2) model testing (n = 124). Three pediatric radiologists measured all fibular shaft lengths. An ordinary linear regression model was fitted to dataset 1, and the model was evaluated using dataset 2. Readers also estimated infant bone ages in dataset 2 using (1) the hemiskeleton method of Sontag, (2) the hemiskeleton method of Elgenmark, (3) the hand/wrist atlas of Greulich and Pyle, and (4) the knee atlas of Pyle and Hoerr. For validation, we selected lower-extremity radiographs of 114 normal infants with no suspicion of abuse. Readers measured the fibulas and also estimated bone ages using the knee atlas. Bone age estimates from the proposed method were compared to the other methods. The proposed method outperformed all other methods in accuracy and reproducibility. Its accuracy was similar for the testing and validating datasets, with root-mean-square error of 36 days and 37 days; mean absolute error of 28 days and 31 days; and error variability of 22 days and 20 days, respectively. This study provides strong support for an infant bone age estimation technique based on fibular shaft length as a more accurate alternative to conventional methods. (orig.)

  12. Fracture of the femoral shaft in children: advantages of the descending medullary nailing.

    Science.gov (United States)

    Bourdelat, D

    1996-01-01

    In a 7-year period, 70 children aged 5-15 years (mean 9.2 years) were treated for a fracture of the femoral shaft (73 fractures: 71 closed and 2 open) by flexible medullary nailing, either ascending (12 cases) or descending (61 cases). Although the classic treatment is use of the ascending route described by the Nancy team, the subtrochanteric descending route was preferred for its simplicity. Noninvolvement of the knee by the insertion of the nail allows earlier autonomy in children. Results were satisfactory and no complications related to the method were observed. Biomechanical principles are also respected by such treatment.

  13. Method of indicating the position of a drill head of a shaft drilling unit

    Energy Technology Data Exchange (ETDEWEB)

    Gudkov, G.D.; Fayner, L.B.; Gurerich, D.I.

    1982-01-01

    A method of indicating the position of a drill head of a shaft drilling unit consists of duplicating its position by an indicator which moves along with movement of the drill head during its forward and backward movements. In order to reduce time spent on auxilliary operations mismatching of the reading of the indicator and the position of the drill head is accomplished due to automatic rejection of the accumulated air during backward motion. The indicated mismatching is rejected at the end of the backward cycle.

  14. NEW TECHNOLOGY AND MACHINE TOOL FOR THE FORMING OF THE REAR AXLE SHAFT OF LIGHT TRUCK

    Institute of Scientific and Technical Information of China (English)

    Han Yingchun; Yu Duonian; Wang Xueming

    2004-01-01

    A new technology of forward extrusion and cross rolling has been developed to process the rear axle shaft sleeve of light truck with the use of tube billets. This technology is characterized by large reductions of material, energy and cost of production and has significant economical benefits. This technology is stable and reliable. The three rolls transverse rolling mill built based on this technology has novelty construction, higher production efficiency, non-vibration and noise. The research results have been extensively applied to light trucks and farm transport with load of 1 to 3 tones.

  15. HE NEW METHOD OF MINIMALLY INVASIVE OSTEOSYTHESIS OF HUMERAL SHAFT FRACTURES WITH HELICAL PLATES

    Directory of Open Access Journals (Sweden)

    A. Y. Kochish

    2016-01-01

    Full Text Available The purpose of investigation is to approve the new method of minimally invasive plate osteosynthesis in cases of diaphyseal humeral shaft fractures with helical plate.Materials and methods. During experimental cadaveric part of the study implantation of long helical plate on humerus using minimally invasive technique on 14 fresh cadaveric shoulders was done. plate was inserted from two incisions 3-5 cm long in the upper part of the shoulder on the lateral side and in the lower part on the anterior side. Clinical part of the study included 31 patients with isolated humeral shaft fractures and humeral shaft fractures associated with fractures of proximal humerus and treated by minimally invasive fixation with helical plate.Results. Cadaveric study included preparation and special measuring and showed that implantation of the helical plate in proposed way gives safe distances between plate and axial, radial, musculocutaneous, median nerves, main humeral vessels and tendon of the long head of the biceps.Results of the clinical part of the study: radiological evidence of bone healing were observed on the 12 weeks in 10 from 28 cases (36%, on the 18 weeks in 18 from 25 (72%, on the 24 weeks in all 25 cases (100%. On the 24 weeks after surgery results on the DASH scale in average were 13±3,6 (from 3 to 36. Where in good results were in 17 (68% cases, satisfactory in 8 (32% cases. On the Constant Shoulder Score at the same time averege results were 80±4,63 (from 60 to 91. Exellent result was in 7 (28% cases, good in 12 (48%, satisfactory in 5 (20% cases and bad in one (4% case with subacromial impidgement after wrong plate positioning. There were no any cases of vascular and neurological complications and nonunions.Conclusion. Minimally invasive fixation of humeral shaft fractures with helical plates is safe and effective method of surgical treatment with good dynamic of functional rehabilitation and can be recommended for clinical use.

  16. Long term stability analysis of cast iron shaft linings after Coal Mine closure and flooding

    Energy Technology Data Exchange (ETDEWEB)

    Hadj-Hassen, F. [Ecole des Mines de Paris - CGES, 77 - Fontainebleau (France); Bienvenu, Y. [Ecole des Mines de Paris, CM, 91 - Evry (France); Noirel, J.F. [Charbonnages de France, DTN, 57 - Freyming Merlebach (France); Metz, M. [charbonnages de France, ESA, 57 - Freyming Merlebach (France)

    2005-07-01

    This paper presents the results of a study conducted to analyse the long term stability of the cast iron shaft lining after coal mine closure and flooding. The attention is mainly focused on the behaviour during the critical phase of flooding as well as the phase corresponding to the disappearance of the water pressure and the stabilization of the environment. This pluri-disciplinary study was conducted by a team combining specialists in rock mechanics who identified the main risks and the conditions of stability of the lining and specialists in metallurgy who studied the composition of the cast iron and its corrosion behaviour after exposure to mine water. (authors)

  17. Comparison of two kinds of intramedullary nails in the treatment of femoral shaft fractures in adults

    Institute of Scientific and Technical Information of China (English)

    CHEN Wei; WANG Juan; SU Yan-ling; ZHAGN Qi; WANG Bo; LI Zhi-yong; ZHANG Ying-ze

    2011-01-01

    Background Intramedullary nails have been widely used in treating femoral shaft fractures.However,end caps falling into soft tissue intraoperatively may cause trouble to surgeons,prolong operative time and increase radiation exposure.Additionally,difficulties may be encountered when removing nails because of callus formation over the nail tip.We performed a prospective study to compare two types of nails in managing femoral shaft fractures.Methods Group I consisted of seventy-four patients with unilateral femoral shaft fractures treated with cannulated interlocking anatomical femoral intramedullary nails.Group Ⅱ consisted of seventy-eight patients treated with cannulated interlocking anatomical femoral intramedullary nails with tail wires.The patients' ages,fracture severity,duration of operation,fluoroscopy time,blood loss and falls of end caps into soft tissue were recorded.Nails were removed after fracture healing.The duration of operation and blood loss during nail removal were recorded.Results There were no significant differences between groups with respect to age and fracture severity (P>0.05).End caps fell into soft tissue 17 times in 15 cases in group Ⅰ and 21 times in 16 cases in group Ⅱ.An average of seven minutes was spent recovering a lost cap in group Ⅰ.In group Ⅱ,all lost caps were recovered immediately.The duration of operation and fluoroscopy time in group Ⅱ was significantly less than in group Ⅰ (P <0.05).Asymptomatic palpable nodules were detected in 4 cases in group Ⅱ.Nail removals were performed on 58 patients in group Ⅰ and 69 patients in group Ⅱ.The duration of operation,blood loss and complications in group Ⅱ were less than in group Ⅰ (P<0.05).Conclusion Intramedullary nails with tail wires facilitate both fracture fixation and nail removal,which can be used to treat femoral shaft fractures with less radiation exposure,shorter surgical time and fewer complications.

  18. New configuration of bearings for rotor shafts in wind turbines; Neue Lagerkonfiguration fuer Windturbinen-Rotorwellen

    Energy Technology Data Exchange (ETDEWEB)

    Pontius, Thierry [The Timken Company, Canton, OH (United States); Ionescu, Laurentiu

    2010-07-01

    Nowadays, the main bearings of a wind turbine consist of a double-serial pendulum roller bearing as a fixed bearing. This is not an ideal solution. Under this aspect, the authors of the contribution under consideration report on a new configuration of bearings for rotor shafts in wind turbines. A combination of a double-serial tapered roller bearing and a cylinder roller bearing has clear advantages in relation to the use of two pendulum roller bearings: (1) Outstanding radial and axial load carrying capacity; (2) Improved load zone with a balanced distribution of load distribution and an optimized L10 lifetime; (3) Particularly good static and dynamic rigidity.

  19. Nevada Nuclear Waste Storage Investigations: exploratory shaft. Phase I. Conceptual design report

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, D.C.; Merson, T.J.; McGuire, P.L.; Sibbitt, W.L.

    1982-06-01

    It is proposed that an Exploratory Shaft (ES) be constructed in Yucca Mountain on or near the southwest portion of the Nevada Test Site (NTS) as part of the Nevada Nuclear Waste Storage Investigations. This document describes a conceptual design for an ES and a cost estimate based on a set of construction assumptions. Included in this document are appendixes consisting of supporting studies done at NTS by Fenix and Scisson, Inc. and Holmes and Narver, Inc. These appendixes constitute a history of the development of the design and are included as part of the record.

  20. Behavior of primary coolant pump shaft seals during station blackout conditions

    Energy Technology Data Exchange (ETDEWEB)

    Hill, R.C.; Rhodes, D.B.

    1986-09-12

    An assessment is made of the ability of typical Reactor Coolant Pump (RCP) Shaft Seals to withstand the conditions predicted for a station blackout (loss of all alternating current power) at a nuclear power station. Several factors are identified that are key to seal stability including inlet fluid conditions, pressure downstream of the seal, and geometrical details of the seal rings. Limits for stable seal operation are determined for various combinations of these factors, and the conclusion is drawn that some RPC seals would be near the threshold of instability during a station blackout. If the threshold were exceeded, significant leakage of coolant from the primary coolant system could be expected.

  1. Ipsilateral Fracture Shaft Femur with Neglected Dislocation of Prosthesis: A Case Report

    Directory of Open Access Journals (Sweden)

    Mantu Jain

    2013-10-01

    Full Text Available Introduction: Neglected hip dislocation is rare in today’s world and after prosthesis replacement even rarer finding. However such patients may not report to surgeons until they develop secondary complications. Management of such patient’s is a challenge to the treating surgeon and need to be tailored suiting to patient’s demands, expectations and constraints of financial resources. We did not find a similar case in the electronic and print media and therefore report this case which was innovatively managed. Case Report: A 60 year farmer presented with fracture shaft femur and ipsilateral dislocation prosthesis of right hip. He had a hemiarthroplasty done for fracture neck of femur in the past but used to walk with a lurch since he started to ambulate after discharge. However he was satisfied despite “some problems” which had caused shortening of his limb. The patient was informed of the various treatment options and their possible complications. He expressed his inability to afford a Total Hip Arthroplasty (THA at any stage and consented for other options discussed with him. The patient was positioned supine and adductor tenotomy done. Next he was positioned laterally and the fracture was fixed with heavy duty broad dynamic compression plate and screws. The wound was temporarily closed. Now through the previous scar via posterior approach the hip was exposed. The prosthesis was found to be firmly fixed to the proximal femur. The acetabulum was cleared with fibrous tissue. All attempts the prosthesis to relocate the prosthesis failed after several attempts and it was best decided to leave alone. Post operatively period was uneventful. At follow up he refused for any further manoeuvre in future inform of heavy traction and attempts to reduce the same. At one year when he was walking unaided and his X-rays showed that fracture had well united his SF-36 score was PCS – 49.6 and MCS – 51.9. Conclusion: Ipsilateral shaft femur fracture

  2. Treatment of a femoral shaft fracture in a patient with congenital hip disease: a case report

    Directory of Open Access Journals (Sweden)

    Koutsostathis Stefanos D

    2010-07-01

    Full Text Available Abstract Introduction We present a rare case of two concomitant morbidities treated in one operation. To our knowledge, this is the first report of its kind in the literature. Case presentation A 57-year-old Greek woman was admitted to the emergency department having sustained a spiral mid-shaft femoral fracture. She also suffered from an ipsilateral hip congenital dysplasia with ankylosed hip joint due to severe arthritis. She was treated with a total hip arthroplasty using a long stem performing as an intramedullary nail. Conclusion We undertook a complex operative treatment of both co-morbidities in a one stage procedure with a satisfactory clinical result.

  3. Cephalomedullary fixation for femoral neck/intertrochanteric and ipsilateral shaft fractures: surgical tips and pitfalls

    Institute of Scientific and Technical Information of China (English)

    Kamal Bali; Nitesh Gahlot; Sameer Aggarwal; Vijay Goni

    2013-01-01

    Objective:Surgical management options for femoral shaft fracture and ipsilateral proximal femur fracture vary from single-implant to double-implant fixation.Cephalomedullary fixation in such fractures has relative advantages over other techniques especially because of less soft tissue dissection and immediate postoperative weight beating with accelerated rehabilitation.However,the surgery is technically demanding and there is a paucity of literature describing the surgical techniques for this fixation.The aim of the study was to describe the surgical technique of cephalomedullary fixation for femoral shaft fracture and ipsilateral proximal femur fracture.Methods:Sixteen cases (10 males and 6 females with a mean age of 41.8 years) ofipsilateral proximal femur and shaft fractures were treated by single-stage cephalomedullary fixation at tertiary level trauma center in northern India.The fractures were classified according to AO classification.An intraoperative record of duration of surgery as well as technical challenges unique to each fracture pattern was kept for all the patients.ResuRs:The most common proximal femoral pattern was AO B2.1 observed in 9 of our patients.The AO B2.3 fractures were seen in 4 patients while the AO A1.2 fractures in 3 patients.Four of the AO B2.1 and 2 of the AO B2.3 fractures required open reduction with Watson-Jones approach.The mean operative time was around 78 minutes,which tended to decrease as the surgical experience increased.There was only one case of malreduction,which required revision surgery.Conclusion:Combination of ipsilateral femoral shaft fracture and neck/intertrochanteric fracture is a difficult fracture pattern for trauma surgeons.Cephalomedullary nail is an excellent implant for such fractures but it requires careful insertion to avoid complications.Surgery is technically demanding with a definite learning curve.Nevertheless,a majority of these fractures can be surgically managed by singleimplant cephaiomedullary

  4. Research into the impact of shafts misalignment of turbocompressor installation on power characteristics of a drive engine

    Science.gov (United States)

    Kipervasser, M. V.; Gerasimuk, A. V.

    2016-10-01

    In the present paper the emergency situation in operation of a turbocompressor installation is considered, which leads to shafts misalignment, connected by rigid couplings, of the drive synchronous electric motor and multiplicator is considered. Misalignment of shafts causes vibrations in the course of work of a turbine unit that, in its turn, can result in untimely wear of bearings, loosening of different fasteners and breakdown of the whole installation. The analysis of shafts misalignment of electric motor and planetary gearbox (multiplicator) regarding the emergence of mechanical power surge and derivation of corresponding equations is performed. The mathematical modelling of a turbine unit operation taking into account misalignment in MatLAB Simulink is carried out. The graphs of mechanical power surges on the shaft of the electric motor and current surges in the phase of its stator are received. The conclusion about the possibility of recording stator current surges by standard measurement methods and use of this fact for development of a current protection against misalignment of shafts is made.

  5. Study of Effect of Quenching Deformation Influenced by 17CrNiMo6 Gear Shaft of Carburization

    Science.gov (United States)

    Pang, Zirui; Yu, Shenjun; Xu, Jinwu

    The 17CrNiMo6 steel is mainly used for the gear shaft of large modulus in many fields of heavy industry such as mining, transit, hoist, forging and so on[1]. The size of addendum circle and common normal line is changed a lot beyond the tolerance because of the long time of carburizing process and the out-of-step structural stress and thermal stress during the quenching process. And thus the posterior grinding efficiency and quality are influenced. In the paper comparison and analysis of the deformation affected by solid and hollow gear shafts were done and the methods of simulation and practice were both used. The results are as follows: the deformation of gear shaft was small before and after carburizing while that of gear shaft was large before and after quenching because of different cooling velocity, structure and hardness of each position. And the deformation of hollow was much smaller than that of solid. Therefore, if the hollow gear shaft is used, the waste of material will be decreased, and finishing cost will be reduced, and thus the technology of heat treatment will be optimized.

  6. FE-simulation of the Presta joining process for assembled camshafts - local widening of shafts through rolling

    Science.gov (United States)

    Scherzer, R.; Silbermann, C. B.; Ihlemann, J.

    2016-03-01

    Considerable weight benefits and the option to combine various steel alloys of the single parts are the major advantages of assembled over conventional camshafts. The Presta joining process is the leading manufacturing method of assembled camshafts in the global market. The process is divided into two substeps. At first, the outer diameter of the shaft is widened with a profile oriented orthogonal to the shaft axis at the intended cam seat. At this position the shaft is subsequently joined with a cam with an internal profile oriented parallel to the shaft axis. As a result, these perpendicular profiles form a tight fit due to plastic deformations. Consequently the simulation of the manufacturing process has to start with the simulation of the rolling of the shaft. The resulting profile requested in this step is axisymmetric, but the arrangement of tools is not. Thus a three-dimensional model is required, which is presented in this work. Furthermore, the infeed of the rolling tool is unknown and controlled by the stiffness of the holders of the rolling tool. This work shows the modeling of this behavior. To predict realistic results for the underlying process, the use of precise material models is essential in order to take several hardening mechanisms into account. However, the use of complex material models implies additional effort, which is shown in this work.

  7. Construction Experiences of Mine Main Shaft in Shaozhai Mine%邵寨煤矿主井施工经验

    Institute of Scientific and Technical Information of China (English)

    李治祥

    2014-01-01

    A common method was applied to the early stage construction of the mine main shaft in Shao-zhai Mine ,when the mine shaft was in an aquifer of Cretaceous Luohe Formation ,due to the water in‐flow too high ,a pre-grouting at the shaft sinking face ,backfill grouting ,cut-off trench set in the shaft liner ,enlarged water drainage capacity and other comprehensive water prevention and control measures were applied to control the water inflow .The results were small ,the mine shaft was hard to continue the downward sinking and the common construction method had to change to the ground freezing method construction .The ground freezing method construction was taken 189 days and was success‐fully completed.%邵寨煤矿主井前期采用普通法施工,在进入白垩系洛河组含水地层后,由于涌水量太大,采用工作面预注浆、壁后注浆、井壁设置截水槽、增大排水能力等综合防治水措施加以治理,收效甚微,井筒难以继续向下掘进,不得不改用冻结法施工。冻结法施工历时189d ,顺利完成。

  8. Extension of the 7{sup th} level south shaft-landing, 10 shaft, RAG Prosper Haniel colliery; Auffahrung des suedlichen Fuellorts Schacht 10, 7. Sohle auf dem Bergwerk Prosper-Haniel

    Energy Technology Data Exchange (ETDEWEB)

    Schlueter, Hartmut [RAG Steinkohle AG, Bottrop (Germany). Bereich Sonderprojekte auf dem Bergwerk Prosper-Haniel; Luettig, Frank [RAG Deutsche Steinkohle AG, Herne (Germany). Servicebereich Technik und Logistikdienste; Barth, Ulrich [Thyssen Schachtbau GmbH, Muelheim an der Ruhr (Germany)

    2011-03-15

    During the further sinking of shaft 10 the landing on the 7{sup th} level was bilaterally discontinued for approx. 10 m. In September 2008, with the drifting of the lateral C467 the interconnection was effected at the northern landing. Based on a further detail investigation of the rock mechanics and the experience gathered in the establishment of the northern landing the recommendation for the southern landing was to perform the further drifting by starting from shaft 10 and not to head for the shaft once more. Owing to the large cross section of the southern landing the planning of the drifting required solutions that are not normally applied in ordinary roadheading business. (orig.)

  9. Forced Axial and Torsional Vibrations of a Shaft Line Using the Transfer Matrix Method Related to Solution Coefficients

    Institute of Scientific and Technical Information of China (English)

    Kandouci Chahr-Eddine; Adjal Yassine

    2014-01-01

    This present paper deals with a mathematical description of linear axial and torsional vibrations. The normal and tangential stress tensor components produced by axial-torsional deformations and vibrations in the propeller and intermediate shafts, under the influence of propeller-induced static and variable hydrodynamic excitations are also studied. The transfer matrix method related to the constant coefficients of differential equation solutions is used. The advantage of the latter as compared with a well-known method of transfer matrix associated with state vector is the possibility of reducing the number of multiplied matrices when adjacent shaft segments have the same material properties and diameters. The results show that there is no risk of buckling and confirm that the strength of the shaft line depends on the value of the static tangential stresses which is the most important component of the stress tensor.

  10. Comparison of residual stresses in sand- and chill casting of ductile cast iron wind turbine main shafts

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Frandsen, J. O.; Hattel, Jesper Henri

    2015-01-01

    In this work, simulations of pouring, solidification and cooling, and residual stress evolution of sand and chill cast wind turbine main shafts is performed. The models are made in the commercial software MAGMAsoft. As expected, the cooling rate of the sand casting is shown to be much lower than...... for the chill casting, resulting in a very course microstructure.From the simulations the nodule count is found to be 17 nodules per mm2 and 159 nodules permm2 for the sand and chill casting, respectively, in the critical region of the main bearing seat.This is verified from nodule counts performed on the real...... cast main shafts. Residual stressevaluations show an overall increase of the maximum principal stress field for the chill casting,which is expected. However, the stresses are found to be in compression on the surface of thechill cast main shaft, which is unforeseen....

  11. Femoral shaft fracture callus formation after intramedullary nailing: a comparison of interlocking and Ender nailing.

    Science.gov (United States)

    Yamaji, Tetsuo; Ando, Kenichi; Nakamura, Toshiyasu; Washimi, Ohsuke; Terada, Nobuki; Yamada, Harumoto

    2002-01-01

    Intramedullary nailing is widely used for the operative treatment of femoral fractures. Recently, the biologic healing of fractures has become better understood from fundamental investigations. However, there has been no clinical comparison between the fracture healing process with these two fixation methods. The purpose of this study was to use radiographs to compare callus formation with two types of intramedullary nailing for femoral shaft fractures: reamed interlocking (IL) nails and Ender nails. Femoral shaft type A fractures (AO classification) were studied. Twenty-seven fractures were treated with reamed IL nailing, and 81 fractures were treated with Ender nailing. The callus area was calculated from the maximum cross-sectional area on the anteroposterior and lateral radiographs. The callus appeared at a mean of 3.9 weeks after surgery in the IL group, and at a mean of 2.8 weeks in the Ender group ( P Ender groups, fracture healing was noted at a mean of 3.4 and 2.0 months, respectively. The mean area of callus formation in the IL and Ender nailing groups was 439.5 mm(2) and 699.4 mm(2), respectively ( P Ender nailing results in abundant callus, which forms at an earlier stage after the procedure than in patients treated with IL nailing. Dynamization at the fracture site is reported to increase external callus formation. Our results indicate that the elasticity of the fixation obtained with Ender nailing promotes callus formation.

  12. P Voltage Control of DFIG with Two-Mass-Shaft Turbine Model Under Utility Voltage Disturbance

    Directory of Open Access Journals (Sweden)

    Hengameh Kojooyan Jafari

    2016-06-01

    Full Text Available Doubly fed induction generators as a variable speed induction generators are applied instead of other electric machines in wind power plants to be connected to the grid with flexible controllers. Nowadays one of the most important subjects in wind farms is control of output power delivered to the grid under utility disturbance. In this paper, a doubly-fed induction generator with external rotor resistance and power converters model as an external voltage source having an adjustable phase and amplitude with an ordinary turbine connected to one mass shaft model and also two mass shaft model, is used and controlled by a P voltage controller to control the output active power for typical high and low wind speeds under two conditions of utility disturbance; while time of disturbance is not too long to change the domain of external rotor voltage source and also while time is long and the domain of external rotor voltage decreases.Simulation results show that P voltage controller can control output active power under 27% stator voltage drop down for typical low wind speed and 11% stator voltage drop down for typical high wind speed in long time disturbance while 80% of rotor external voltage domain drops down under short time utility disturbance.

  13. Development and Simulation of a Type of Four-Shaft ECVT for a Hybrid Electric Vehicle

    Directory of Open Access Journals (Sweden)

    Yong Zhang

    2016-02-01

    Full Text Available In hybrid electric vehicles with power-split configurations, the engine can be decoupled from the wheel and operated with improved fuel economy, while the entire efficiency of the powertrain is affected by the circular electric power flow. Two planetary gear (2-PG sets with adding brakes/clutches, namely a type of four shaft elelctric continuously variable transmission (ECVT can provide multi-mode operation for the powertrain and extend the efficient area. First, a conventional 2-PG AT (Automatic Transmission architecture is investigated. By analyzing and comparing the connection and operating modes based on the kinematic relationship and lever analogy, a feasible four-shaft ECVT architecture with two brakes and two simplified versions are picked. To make a trade-off between fuel economy and configuration complexity, an instantaneous optimal control strategy based on the equivalent consumption minimization strategy (ECMS concept is then developed and employed as the unified optimization method in the simulations of three different configurations. Finally, the simulation results show that the simplified versions are suboptimal sets and the fuel economy is sacrificed by the limits of different modes. From the viewpoint of concept design, a multi-mode power-split configuration is more suitable for hybrid electric vehicles. This research applied a systematic methodology from concept design to energy management optimization, which can provide the guidelines for researchers to select a suitable multi-mode power-split hybrid powertrain.

  14. Femoral shaft fracture osteosynthesis in a critically ill patient under Extracorporeal Membrane Oxygenation (ECMO

    Directory of Open Access Journals (Sweden)

    Calvo Cristobal

    2016-01-01

    Full Text Available Introduction: Extracorporeal Membrane Oxygenation (ECMO is an invasive procedure used in critically ill patients with catastrophic pulmonary failure or cardiogenic shock in which conventional management has failed. These patients are managed with permanent anticoagulation, with increased bleeding risk. Hemorrhage is the main reported complication. Case: A 25-year-old polytraumatized woman, both lower limbs amputated and a left femoral shaft fracture with catastrophic pulmonary failure (Murray score 4 that required intensive management care with ECMO. During her evolution definitive femoral shaft osteosynthesis with a nail as required and the medical team decided to operate on the patient under ECMO. She recovered with fluctuations in her hematocrit, but was hemodynamically stable. The patient recovered satisfactorily, was weaned from ECMO and commenced her rehabilitation program. At 16 months, she was almost autovalent, and full consolidation was achieved, with no complication of the implants. Discussion: ECMO is a life-saving support, but requires permanent anticoagulation, which implies a high risk of hemorrhages, specially for surgical treatment. This patient underwent an osteosynthesis surgery satisfactorily. Hematoma was the only complication of her intramedullary femoral nail, without compromising hemodynamics. This case shows that patients on ECMO can undergo a major orthopedic surgery in selected cases.

  15. Study on double-shaft mixing paddle undergoing planetary motion in the laminar flow mixing system

    Directory of Open Access Journals (Sweden)

    Jiaqi Zhang

    2015-06-01

    Full Text Available This article has studied the impact of double-shaft mixing paddle undergoing planetary motion on laminar flow mixing system using flow field visualization experiment and computational fluid dynamics simulation. Digital image processing was conducted to analyze the mixing efficiency of mixing paddle in co-rotating and counter-rotating modes. It was found that the double-shaft mixing paddle undergoing planetary motion would not produce the isolated mixing regions in the laminar flow mixing system, and its mixing efficiency in counter-rotating modes was higher than that in co-rotating modes, especially at low rotating speed. According to the tracer trajectory experiment, it was found that the path line of the tracer in the flow field in co-rotating modes was distributed in the opposite direction to the path line in counter-rotating modes. Planetary motion of mixing paddle had stretching, shearing, and folding effects on the trajectory of the tracer. By means of computational fluid dynamics simulation, it was found that axial flows and tangential flows produced in co-rotating and counter-rotating modes have similar flow velocity but opposite flow directions. It is deduced from the distribution rule of axial flow, radial flow, and tangential flow in the flow field that axial flow is the main reason for causing different mixing efficiencies between co-rotating and counter-rotating modes.

  16. Analysis of Gear Wheel-shaft Joint Characterized by Comparable Pitch Diameter and Mounting Diameter

    Directory of Open Access Journals (Sweden)

    J. Ryś

    2003-01-01

    Full Text Available This paper presents the design procedure for a gear wheel-shaft direct frictional joint. The small difference between the operating pitch diameter of the gear and the mounting diameter of the frictional joint is the key feature of the connection. The contact surface of the frictional joint must be placed outside the bottom land of the gear, and the geometry of the joint is limited to the specific type of solutions.The strength analysis is based on the relation between the torque and statistical load intensity of the gear transmission. Several dimensionless parameters are introduced to simplify the calculations. Stress-strain verifying analysis with respect to combined loading, the condition of appropriate load-carrying capacity of the frictional joint and the fatigue strength of the shaft are applied to obtain the relations between the dimensions of the joint and other parameters. The final engineering solution may then be suggested. The approach is illustrated by a numerical example.The proposed procedure can be useful in design projects for small, high-powered modern reducers and new-generation geared motors, in particular when manufactured in various series of types.

  17. HOMOGENIZATION—BASED TOPOLOGY DESIGN FOR PURE TORSION OF COMPOSITE SHAFTS

    Institute of Scientific and Technical Information of China (English)

    袁振; 吴长春; 李华

    2003-01-01

    In conjunction with the homogenization theory and the finite element method, themathematical models for designing the cross-section of composite shafts by maximizing the torsionrigidity axe developed in this paper. To obtain the extremal torsion rigidity, both the cross-section ofthe macro scale shaft and the representative microstructure of the composite material are optimizedusing the new models. The micro scale computational model addresses the problem of finding theperiodic microstructures with extreme shear moduli. The optimal microstructure obtained with thenew model and the homogenization method can be used to improve and optimize natural or artificialmaterials. In order to be more practical for engineering applications, cellular materials rather thanranked materials are used in the optimal process in the existence of optimal bounds for the elasticproperties. Moreover, the macro scale model is proposed to optimize the cross-section of the torsionalshaft based on the tailared composites. The validating optimal results show that the models are veryeffective in obtaining composites with extreme elastic properties, and the cross-section of the compositeshaft with the extremal torsion rigidity.

  18. Correlation of drillhole and shaft logs. Waste Isolation Pilot Plant (WIPP) project, southeastern New Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Jarolimek, L.; Timmer, M.J.; Powers, D.W.

    1983-03-01

    This report on stratigraphic correlations from drillhole and shaft data along a generally north-south section across the potential extent of underground excavations of the Waste Isolation Pilot Plant (WIPP) facility was prepared as part of the Site Validation Field Program Plan. The results provide (1) input for the report entitled ''Results of Site Validation Experiments,'' (2) input for other WIPP-related investigations, including the Design Validation Program, and (3) a framework for further underground activities at WIPP. In general, this correlation study confirmed previous findings, including: relatively high consistency of thickness and lateral continuity of all beds within the Salado Formation, especially in the host rock interval; gentle, generally south and southeastward dips/slopes of the host rock interval strata; close correspondence between stratigraphic data obtained from the present underground excavations and data derived from the previous investigative drillholes and shafts; and depositional origin of the undulations on the top of Marker Bed (MB) 139 and relatively small variation in its thickness (1.2 to 4.1 feet).

  19. Impact of Shaft Stiffness on Inertial Response of Fixed Speed Wind Turbines

    Institute of Scientific and Technical Information of China (English)

    2012-01-01

    Future power' system faces several challenges, one of them is the high penetration level of intermittent wind power generation, providing small or even no inertial response and being not contributing to the frequency stability. The effect of shaft stiffness on inertial response of fixed speed wind turbines is presented. Four different drive-train models based on the multi-body system are developed. The small-signal analysis demonstrates no significant differences between models in terms of electro-mechanical eigen-values for increasing shaft stiffness. The natural resonance frequency of drive-train torsion modes shows slightly different values between damped and undamped models, but no significant differences are found in the number-mass models. Time-domain simulations show the changes in the active power contribution of a wind farm based on a fixed speed wind turbine during the system frequency disturbance. The changes in the kinetic energy during the dynamic process are calculated and their contribution to the inertia constant is small and effective. The largest contribution of the kinetic energy is provided at the beginning of the system frequency disturbance to reduce the rate of the frequency change, it is positive for the frequency stability.

  20. DNA extraction from hair shafts of wild Brazilian felids and canids.

    Science.gov (United States)

    Alberts, C C; Ribeiro-Paes, J T; Aranda-Selverio, G; Cursino-Santos, J R; Moreno-Cotulio, V R; Oliveira, A L D; Porchia, B F M M; Santos, W F; Souza, E B

    2010-12-21

    Wild felids and canids are usually the main predators in the food chains where they dwell and are almost invisible to behavior and ecology researchers. Due to their grooming behavior, they tend to swallow shed hair, which shows up in the feces. DNA found in hair shafts can be used in molecular studies that can unravel, for instance, genetic variability, reproductive mode and family structure, and in some species, it is even possible to estimate migration and dispersion rates in given populations. First, however, DNA must be extracted from hair. We extracted successfully and dependably hair shaft DNA from eight wild Brazilian felids, ocelot, margay, oncilla, Geoffroy's cat, pampas cat, jaguarundi, puma, and jaguar, as well as the domestic cat and from three wild Brazilian canids, maned wolf, crab-eating fox, and hoary fox, as well as the domestic dog. Hair samples came mostly from feces collected at the São Paulo Zoo and were also gathered from non-sedated pet or from recently dead wild animals and were also collected from museum specimens. Fractions of hair samples were stained before DNA extraction, while most samples were not. Our extraction protocol is based on a feather DNA extraction technique, based in the phenol:chloroform:isoamyl alcohol general method, with proteinase K as digestive enzyme.

  1. One-stage emergency treatment of open grade IIIB tibial shaft fractures with bone loss.

    Science.gov (United States)

    Tropet, Y; Garbuio, P; Obert, L; Jeunet, L; Elias, B

    2001-02-01

    The purpose of this study was to report the authors' experience with emergency reconstruction of severe tibial shaft fractures. Five male patients were admitted to the emergency room with a grade IIIB open tibial shaft fracture with bone loss (average age, 33 years; age range, 18-65 years). Injuries were the result of motorcycle accidents (N = 2), pedestrian accidents (N = 1), gunshot wound (N = 1), and paragliding fall (N = 1). Primary emergent one-stage management for all patients consisted of administration of antibiotics, debridement, stabilization by locked intramedullary nailing, bone grafting from the iliac crest, and coverage using free muscle flaps (four latissimus dorsi and one gracilis). The average follow-up was 21 months (range, 8 months-3.5 years). Partial weight bearing with no immobilization was started at 3 months, and full weight bearing began 5 months after trauma. No angular complications and no nonunions were observed. There was one case of superficial infection without osteitis. All fractures healed within 6 months in 4 patients and within 10 months in 1 patient. At the last follow-up examination, ankle and knee motion was normal and no pain was noted, except for 1 patient who had associated lesions (ankle motion reduced by 50%). Aggressive emergency management of severe open tibial fractures provides good results. It improves end results markedly, not only by reducing tissue loss from infection, but also reducing healing and rehabilitation times.

  2. The shaft fractures of the radius and ulna in children: current concepts.

    Science.gov (United States)

    Sinikumpu, Juha-Jaakko; Serlo, Willy

    2015-05-01

    The incidence of forearm shaft fractures in children has increased in recent years. They are challenging to treat and they can result in several long-lasting complications. The treatment of children's fractures needs to be individualized to their needs. Nonoperative care will be satisfactory for young, preschool children and it is primarily treatment in stable fractures of children at every age. Injury mechanism must be understood to perform appropriate closed reduction. Immobilization using a long-arm cast needs to be focused against the deforming muscle forces - in particular those that rotate - in the forearm, keeping the bones in alignment until bone healing. Operative stabilization by elastic stable intramedullary nailing is the primarily method of treatment in cases of unstable fractures, in particular, in children between preschool age and adolescence. For older children near to skeletal maturity, a rigid plate and screw fixation will be justified. The most common complication after closed treatment is worsening of the alignment and need for repetitive interventions. elastic stable intramedullary nailing results usually in good outcome, and range of forearm rotation is the main feature determining the clinical result. In this article, we report the current concept of paediatric shaft fractures in the radius and ulna.

  3. Minimally invasive plate osteosynthesis for humeral shaft fractures: are results reproducible?

    Science.gov (United States)

    Concha, Juan M; Sandoval, Alejandro; Streubel, Philipp N

    2010-12-01

    Minimally invasive plate osteosynthesis (MIPO) has been advocated as a safe approach to humeral shaft fracture management. We evaluated the reproducibility of this technique in a regional hospital. Thirty-five patients underwent MIPO of humerus shaft fractures. Fifteen patients had an open fracture, six a preoperative radial nerve palsy, and nine a concomitant thoracic, musculoskeletal or vascular injury. At an average 12-month follow-up, 91% of fractures healed after a mean of 12 weeks (range, 8-16). Two infections occurred. Final alignment averaged 4° of varus (range, 5° of valgus to 20° of varus). Active elbow ROM averaged 114° (range, 60-135°) and was less than 100° in nine elbows. Five of six preoperative radial nerve injuries recovered spontaneously. Healing and infection rates in this study are consistent with those reported in the literature. Lower elbow ROM and higher fracture angulation at healing were nevertheless found. MIPO is technically demanding and requires adequate intraoperative imaging and surgical experience in order to obtain adequate fracture alignment. Brachialis muscle scarring and inadequate postoperative rehabilitation may be involved in limited elbow range of motion.

  4. Minimally invasive plating osteosynthesis for mid-distal third humeral shaft fractures.

    Science.gov (United States)

    Lian, Kejian; Wang, Lei; Lin, Dasheng; Chen, Zhiwen

    2013-08-01

    Mid-distal third humeral shaft fractures can be effectively treated with minimally invasive plating osteosynthesis and intramedullary nailing (IMN). However, these 2 treatments have not been adequately compared. Forty-seven patients (47 fractures) with mid-distal third humeral shaft fractures were randomly allocated to undergo either minimally invasive plating osteosynthesis (n=24) or IMN (n=23). The 2 groups were similar in terms of fracture patterns, fracture location, age, and associated injuries. Intraoperative measurements included blood loss and operative time. Clinical outcome measurements included fracture healing, radial nerve recovery, and elbow and shoulder discomfort. Radiographic measurements included fracture alignment, time to healing, delayed union, and nonunion. Functional outcome was satisfactory in both groups. Mean American Shoulder and Elbow Surgeons score and Mayo score were both better for the minimally invasive plating osteosynthesis group than for the IMN group (98.2 vs 97.6, respectively, and 93.5 vs 94.1, respectively; Pshaft fractures. Minimally invasive plating osteosynthesis is more suitable for complex fractures, especially for radial protection and motion recovery of adjacent joints, compared with IMN for simple fractures.

  5. Portable mixed abrasive water jet equipment for rescue in high gas mine shaft

    Institute of Scientific and Technical Information of China (English)

    ZENG Rui; DU Chang-long; XU Rui; ZHAO Jing

    2011-01-01

    In order to rescue a trapped miner and clean out roadways quickly in a high gas mine shaft after a mining mishap, a special portable cold-cutting equipment is needed, the main technology parameters were calculated according to the advanced cold-cutting technology of high pressure abrasive water jet and the portable mixed abrasive water jet equipment (PAWE) was designed to meet the needs of emergency rescue in high gas mine shafts. Tested the PAWE in a high gas environment, and the result shows that the maximum cutting depth of solid iron pipe is 18 mm and the recoilforce of the sprayer is 28.9 N under the conditions that actual cutting pressure is 29 MPa, starting target distance is 10 mm, cutting speed is 180 mm/min and concentration of abrasive is 32%. The course of the experiment in the high gas environment was smooth and continuous, without any explosion. The PAWE is easy to move and operate, but the nozzle which was worn badly in the sprayer should be changed every 8 minutes.

  6. Repacking practice for G-3 engineering driller power unit with drive shaft of dual channel reverse circulation

    Institute of Scientific and Technical Information of China (English)

    Lihong ZHU; Kun YIN; Qingyan WANG; Yong HUANG

    2008-01-01

    In order to satisfy operating requirements for constant core drilling technology in reverse circulation with hollow-through DTH,the power unit of G-3 engineering driller was ameliorated. The new one with dual channel drive shaft, achieved the perfect assemble with transmission structure of the original power unit. It could interconvert according to need by using two sets of drive shafts with direct and reverse circulation. The repacked G-3 engineering driller carried on experiment in the field test in Luanchuan molybdenum mine of Henan, whose effect was very good.

  7. Control Circuitry Using Electronic Emulation of a Synchro Signal for Accurate Control of Position and Rate of Rotation for Shafts

    Science.gov (United States)

    Howard, David E. (Inventor); Smith, Dennis A. (Inventor)

    1992-01-01

    The invention herein disclosed is a digital circuit which emulates a synchro signal in a synchro-resolver follower system for precise control of shaft position and rotation at very low rotational rates. The subject invention replaces the synchro and drive motor in a synchroresolver follower system with a digital and analog synchro emulation circuit for generating the resolver control signal. The synchro emulation circuit includes amplitude modulation means to provide relatively high frequency resolver excitation signals for accurate resolver response even with very low shaft rotation rates.

  8. In-service fatigue cracking of the propeller shafts joined by a spline-pinned construction to the engines of AN-24, AN-26, and IL-18 aircrafts

    Directory of Open Access Journals (Sweden)

    A. Shanyavskiy

    2014-10-01

    Full Text Available The paper delivers a critical review of the research data on the crack initiation and crack growth patterns characteristic of the components of the spline-bolted joints between the propeller shaft and reducer shaft at An-24, An-26, and Il-18 aircrafts. Cracks in the shafts nucleated because of reduced bolt-fastening force. Actually, the bolt (bolts failed first (also by fatigue and then fatigue cracks nucleated and grew in the shafts, the spline surface fretting zones and/or sharp edges of the attachment (bolt-conducting holes making the crack origin sites. The crack growth history shows itself through the regular Macro-Beach Marks, each mark sequentially pointing to the next loading event of the propeller shaft, i.e., to each next flight. The cracks cease growing for some while in the airscrews and their shafts just replaced to another aircraft. For the airscrew shafts, the critically assessed data show the crack growth period Np ranging as five to ten percent of a total running period Nf . We recommend performing nondestructive inspection of the airscrew shafts on every 250- hour running period to ensure the safety flights.

  9. 风力发电机轴电压轴电流对轴承影响及改进措施%Wind turbine generator shaft voltage and shaft current on the bearing and preventive measures

    Institute of Scientific and Technical Information of China (English)

    陈国强; 陈国忠; 徐明; 张杰; 高坡; 刘志强

    2014-01-01

    风力发电机轴承失效频繁发生,在研究应用条件和调查轴承失效的基础上,基本确认了造成轴承失效的根本原因:双馈感应发电机变频驱动所导致的轴承过电流和相应的电腐蚀及润滑、磨损等。本文分析了轴电压轴电流产生的原理和造成的危害,叙述了对轴电压的抑制措施,并在风电场推广应用,实践验证了轴电流抑制技术的有效性。%Bearing failures of windturbine generator are occurring frequently. Based on application studies and bearing investiga-tions main root causes have been identified: electrical current passage, electrical erosion respectively, due to frequency convert-er supply of doubly-fedinduction generator sand lubrication and wear related problems.This paper analyzed the cause of shaft voltage and shaft current and its related harm in doubly-fed wind turbine architecture. Measures to suppress the shaft voltage and shaft current are detailed and put into practice in pilot wind farms. The effectiveness of the measures are approved by field data.

  10. ASSESSMENT OF RELATIONSHIP BETWEEN NECK SHAFT ANGLE AND NECK LENGTH WITH INTEREPICONDYLAR DISTANCE IN FEMUR

    Directory of Open Access Journals (Sweden)

    Ishita Ghosh

    2015-12-01

    Full Text Available Background: Femur is the longest and strongest bone of the body. It transmits body weight from hip bone to tibia in standing position. Femoral neck is a constricted part connecting head with shaft at an angle of about 125°-known as angle of inclination or neck shaft angle (NSA; this facilitates the movement of hip joint enabling the limb to swing clear of pelvis. Abnormal femoral neck angle (FNA may be associated with various clinical problems ranging from harmless in toeing gait in childhood to disabling osteoarthritis in adults. The current study attempted to find out if a co-relation exists between those parameters and other clinically measurable variables like inter-epicondylar distance or distance between greater trochanter to lateral epicondyle. This may help to predict the risk of fracture neck femur without any risk of radiation exposure and proper prophylactic measures can be undertaken (Vit-D, calcium to decrease risk of fracture. Results: Measurements were taken in dry femora mostly in East Indian population. Variables that were measured in 158 dry femora (85 femora from left side and 73 from the right side are: - a Neck shaft angle of femur, b Neck length of femur, c Neck circumference of femur, d Inter-epicondylar distance of femur, e Distance between lateral epicondyle and greater trochanter of femur. No significant difference was found between the right and left sided femoral groups regarding any of the study variables. From the analysis it was revealed that no positive or negative correlation exists between the study variables. Therefore, it is not possible to predict the value of one or more of them from the magnitude of the other variable(s. Conclusions: Our study attempted to find out if it was possible to predict the risk of fracture neck femur by simple clinical procedure without exposing the subjects to radiation hazards associated with a radiological imaging. A screening test and subsequent prophylactic measures could

  11. 考虑船舶轴系校中与弯曲振动的轴承优化布置%Optimization of ship shaft bearings location considering shaft alignment and lateral vibration

    Institute of Scientific and Technical Information of China (English)

    刘学伟; 何其伟; 蒋竞超; 俞翔

    2016-01-01

    船舶在航行过程中,螺旋桨所受到的激振力通过船舶轴系传递给船体并引起尾部振动和噪声,给船舶的乘坐舒适性和安全性带来危害。本文利用传递矩阵法分别建立船舶轴系校中数学模型和弯曲振动数学模型,并使用拟定常法得到螺旋桨叶频和二倍叶频的激励力幅值比值,成比例输入到轴系系统当中,设置轴承间距和轴承标高为变量,以尾轴后轴承受力幅值最小为目标函数。在满足船舶轴系校中标准下,对轴承位置的轴向和径向进行双向优化,得到实例的最优布置方案,通过比较优化前后的尾轴后轴承受力响应幅值,可以发现优化效果明显,对船舶轴系设计与布置具有一定的指导意义。%The exciting force from propeller always transmits through the ship shaft to ship body, and induce vibration of ship stern and noise, causing damage for the ride comfort and safety. In order to solve this problem, shaft alignment and lateral vibration of a shaft are modeled by the transfer matrix method respectively. Quasi-steady empirical method is used for getting the ratio between exciting force of propeller blade frequency and double blade frequency, and then put them into the model according to the ratio. Set the bearing distance and bearing elevation as variables, and minimum force of the propeller shaft rear bearing as objective function, obtaining the optimal solution for bearings location of this shaft under the requirement of shaft alignment. The result shows a good effect after optimization when comparing the response amplitude of rear bearing force. It provides a guide for ship shaft design and bearing arrangement optimization.

  12. 30 CFR 57.4660 - Work in shafts, raises, or winzes and other activities involving hazard areas.

    Science.gov (United States)

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Work in shafts, raises, or winzes and other activities involving hazard areas. 57.4660 Section 57.4660 Mineral Resources MINE SAFETY AND HEALTH... non-fire-retardant wood. Thawing pipes electrically, except with heat tape More than 10 pounds...

  13. Analysis of Mixing Principle and Optimization of Parameter on the Single-shaft Horizontal Total Mixed Ration Mixer

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yu; WANG Defu

    2008-01-01

    The main structure and working principle of the single-shaft horizontal total mixed ration mixer was discussed.For studying the mixing principle,the analysis of force and motion of the material on the paddle were made,and paddle angle and rotational speed of the rotor were determined by the experiment,the main mixing ways were explained.

  14. A non-linear mathematical model for dynamic analysis of spur gears including shaft and bearing dynamics

    Science.gov (United States)

    Ozguven, H. Nevzat

    1991-01-01

    A six-degree-of-freedom nonlinear semi-definite model with time varying mesh stiffness has been developed for the dynamic analysis of spur gears. The model includes a spur gear pair, two shafts, two inertias representing load and prime mover, and bearings. As the shaft and bearing dynamics have also been considered in the model, the effect of lateral-torsional vibration coupling on the dynamics of gears can be studied. In the nonlinear model developed several factors such as time varying mesh stiffness and damping, separation of teeth, backlash, single- and double-sided impacts, various gear errors and profile modifications have been considered. The dynamic response to internal excitation has been calculated by using the 'static transmission error method' developed. The software prepared (DYTEM) employs the digital simulation technique for the solution, and is capable of calculating dynamic tooth and mesh forces, dynamic factors for pinion and gear, dynamic transmission error, dynamic bearing forces and torsions of shafts. Numerical examples are given in order to demonstrate the effect of shaft and bearing dynamics on gear dynamics.

  15. A non-linear mathematical model for dynamic analysis of spur gears including shaft and bearing dynamics

    Science.gov (United States)

    Özgüven, H. N.

    1991-03-01

    A six-degree-of-freedom non-linear semi-definite model with time varying mesh stiffness has been developed for the dynamic analysis of spur gears. The model includes a spur gear pair, two shafts, two inertias representing load and prime mover, and bearings. As the shaft and bearing dynamics have also been considered in the model, the effect of lateral-torsional vibration coupling on the dynamics of gears can be studied. In the non-linear model developed several factors such as time varying mesh stiffness and damping, separation of teeth, backlash, single- and double-sided impacts, various gear errors and profile modifications have been considered. The dynamic response to internal excitation has been calculated by using the "static transmission error method" developed. The software prepared (DYTEM) employs the digital simulation technique for the solution, and is capable of calculating dynamic tooth and mesh forces, dynamic factors for pinion and gear, dynamic transmission error, dynamic bearing forces and torsions of shafts. Numerical examples are given in order to demonstrate the effect of shaft and bearing dynamics on gear dynamics.

  16. DEVELOPMENT OF OPTIMUM SPEED DIAGRAMS FOR SMALL MOVEMENT OF AN ACTUATING DEVICE OF AС ELECTRIC DRIVE-WITH ELASTIC SHAFTING

    Directory of Open Access Journals (Sweden)

    Dobrobaba Y. P.

    2013-10-01

    Full Text Available In this article we describe the optimum speed diagram of moving actuating device of АС electric drive with elastic shafting. Parameters, conditions of existence and dependence of the duration of the cycle from the angle of rotation of actuating device are defined as well

  17. Exploration of Ship Shaft Alignment Technological Process%船舶轴系校中工艺流程探究

    Institute of Scientific and Technical Information of China (English)

    王建政; 张文平; 曹贻鹏; 郑大远

    2011-01-01

    Through some researches, a three-step method for shaft alignment is proposed. The theory takes shaft alignment as the main thread and further sorts out the whole technological process of the installation and alignment of the stern tube, propeller shaft, propeller, intermediate shaft and the main diesel engine. The construction conditions and technical requirements are also studied The three-step method is expected to reduce working hours, increase productivity and improve the quality of shipbuilding.%经过多方调研,提出了轴系校中的三步法,即以轴系校中为主线,对艉轴管、艉轴、螺旋桨、中间轴及主柴油机的安装及校中的整个工艺流程进行梳理,并对其施工条件和技术要求进行了探究.三步法有望缩减工时,提高生产效率,促进造船质量的提高.

  18. Percutaneous clamping of spiral and oblique fractures of the tibial shaft: a safe and effective reduction aid during intramedullary nailing.

    Science.gov (United States)

    Collinge, Cory A; Beltran, Michael J; Dollahite, Henry A; Huber, Florian G

    2015-06-01

    The reduction of tibial shaft fractures during intramedullary nailing is important if limb alignment is to be restored and successful clinical outcomes are expected. We have used a percutaneously applied (or open) clamp or clamps to achieve and maintain reduction during nailing of all amendable tibial shaft fractures. In this article, we describe the technique and preliminary results comparing closed, simple spiral and oblique tibial shaft fractures (OTA 42-A1 and A2) managed with percutaneous clamp-assisted nailing (CAN) versus nailing using manual reduction (MRN) held by the surgical team. In the MRN group, there were an increased fracture gap (P = 0.04) and trends toward malalignment (P = 0.07) and healing time (P = 0.06) compared with the CAN group. There were also trends in clinical; no wound complications occurred in either group. We have found that percutaneous CAN of closed, simple spiral and oblique tibial shaft fractures seems safe and allows for early predictable union with reproducible alignment compared with nailing using MRN.

  19. Modeling ohmic heating in the drying zone of the plasma shaft electric furnace, when recycling the technogenic waste

    Science.gov (United States)

    Aliferov, A. I.; Anshakov, A. S.; Sinitsyn, V. A.; Domarov, P. V.; Danilenko, A. A.

    2016-10-01

    Efficient use of ohmic heating in the drying zone of the plasma shaft furnace for gasification of organic and technogenic wastes is studied. It is shown that by using ohmic heating in the drying zone, energy release takes place in the filling along the entire zone.

  20. Computational fluid dynamics modeling of rope-guided conveyances in two typical kinds of shaft layouts.

    Directory of Open Access Journals (Sweden)

    Renyuan Wu

    Full Text Available The behavior of rope-guided conveyances is so complicated that the rope-guided hoisting system hasn't been understood thoroughly so far. In this paper, with user-defined functions loaded, ANSYS FLUENT 14.5 was employed to simulate lateral motion of rope-guided conveyances in two typical kinds of shaft layouts. With rope-guided mine elevator and mine cages taken into account, results show that the lateral aerodynamic buffeting force is much larger than the Coriolis force, and the side aerodynamic force have the same order of magnitude as the Coriolis force. The lateral aerodynamic buffeting forces should also be considered especially when the conveyance moves along the ventilation air direction. The simulation shows that the closer size of the conveyances can weaken the transverse aerodynamic buffeting effect.

  1. Risk of hip, subtrochanteric, and femoral shaft fractures among mid and long term users of alendronate

    DEFF Research Database (Denmark)

    Abrahamsen, Bo; Eiken, Pia; Prieto-Alhambra, Daniel;

    2016-01-01

    and women aged 50-94 at the start of treatment, who had not previously taken alendronate, 1996-2007. INTERVENTIONS: Treatment with alendronate. MAIN OUTCOME MEASURES: Incident fracture of the subtrochanteric femur or femoral shaft (ST/FS) or the hip. Non-fracture controls from the cohort were matched...... to fracture cases by sex, year of birth, and year of initiation of alendronate treatment. Conditional logistic regression models were fitted to calculate odds ratios with and without adjustment for comorbidity and comedications. Sensitivity analyses investigated subsequent treatment with other drugs...... for osteoporosis. RESULTS: 1428 participants sustained a ST/FS (incidence rate 3.4/1000 person years, 95% confidence interval 3.2 to 3.6), and 6784 sustained a hip fracture (16.2/1000 person years, 15.8 to 16.6). The risk of ST/FS was lower with high adherence to treatment with alendronate (medication possession...

  2. Improved Mathieu repair for coronal and distal shaft hypospadias with moderate chordee.

    Science.gov (United States)

    de Jong, T P; Boemers, T M

    1993-12-01

    A modified Mathieu "flip-flap" technique is described for coronal and distal shaft hypospadias with moderate chordee. The first improvement is the creation of a well vascularised skin flap by leaving the dartos tunica attached to the mobilised skin, thus making it possible to bridge urethral defects up to 2.5 cm. The second improvement is the correction of congenital curvature by partial chordectomy and dorsal plication of the tunica albuginea without the need for circumcision. Preputial reconstruction is possible if required. Twenty patients underwent the procedure with a follow-up of at least 2.5 years; 96 patients had a shorter follow-up. Complications in the group of 20 patients consisted of 1 fistula, 2 meatal stenoses and 1 glanular dehiscence due to severe wound infection. There were no late complications.

  3. Tests of Shaft Seal Systems of Circulation Pumps during Station Blackout

    Energy Technology Data Exchange (ETDEWEB)

    Beisiegel, A.; Foppe, F.; Wich, M.

    2014-07-01

    AREVA GmbH operates a unique Thermal-hydraulic plat form in Germany, France and USA. It is recognised as a test body according to ISO 17025. The Deutsche Akkreditierungsstelle GmbH (DAkkS - German Society for Accreditation) has also certified the Thermal-hydraulic platform as an independent inspection body Type C according to ISO 17020. A part of this platform is the Component Laboratory located in Karlstein, Germany which is in operation since more than 50 years. The testing activities cover a wide range as: Critical Heat Flux Tests, Valve Testing and Environmental Qualification for safety related components. Since 2011 the Component Qualification Karlstein extended their testing scope for different types of Shaft Seal Systems. (Author)

  4. Methodologies of Measuring Mechanical Power Delivered at the Shaft of an Induction Motor Driven by VFD

    Directory of Open Access Journals (Sweden)

    Mariana MANEA

    2012-12-01

    Full Text Available Measuring precise power used by a load of an induction motor driven by a VFD implies a few facts that need to be considered. First, the real electric power. When dealing with waveforms of electric current that contain harmonics, traditional methods of power measuring could lead to inaccurate results. Therefore, further investigation needs to be performed in order to provide meaningful values. Then there is the efficiency. Motor losses are to be taken into account for finding out exactly how much power is being used for a specific application.This paper shows a method of measuring and calculating the electric real power of fundamental harmonic and of extracting an actual output value of mechanical power at the motor shaft. For this purpose we used a data acquisition system made of a basic power quality analyzer and data acquisition software. Harmonic analysis of the waveforms is considered, combined with the use of the true power factor.

  5. Using a Configuration System to Design Toilets and Place Installation Shafts

    DEFF Research Database (Denmark)

    Kudsk, Anders; Hvam, Lars; Thuesen, Christian Langhoff

    2013-01-01

    The aim of this research is to discover how configuration systems can support a product's design process when a high degree of variation is required and a very open or endless space exists for possible configurations. The article is based on an industrial case involving a firm that wishes to offer...... a bathroom configurator to architects. The aim of the configurator is to help architects design a bathroom according to relevent requirements and norms. In offering the configurator, the firm aims to enable a design that can be coordinated with a prefabricated installation shaft sold by the firm, and also...... to create customer leads. Four scenarios are developed for how design can be supported by four different types of configuration technologies. The four scenarios are evaluated in relation to a number of functional and technical requirements. The scenarios indicate that a good and varied range...

  6. Injury of the knee ligaments associated with ipsilateral femoral shaft fractures

    Directory of Open Access Journals (Sweden)

    Marco Tulio Lopes Caldas

    2013-09-01

    Full Text Available OBJECTIVE: With the objective of identifying the incidence of ipsilateral knee ligament injury, thirty-six patients with femoral shaft fractures were evaluated. METHODS: During the osteosynthesis procedure to repair the femur while under anesthesia, all patients underwent a physical examination and X-ray examination. RESULTS: The most common mechanism of injury observed was motorcycle accidents. Of the thirty-six patients that were studied, eleven patients (30.5% had a knee ligament injury. Of the eleven patients, 64% had a cruciate ligament injury. The ligament injury was not treated at the time of the osteosynthesis procedure. CONCLUSION: We highlight the difficulty of diagnosis at the time of admission and the need for systematic physical examination before and after surgical treatment of femoral fracture.

  7. Semiextending Nailing for Combined Shaft and Ankle Injuries of the Leg.

    Science.gov (United States)

    Probe, Robert

    2016-08-01

    Over recent years, orthopaedic traumatologists have been gaining experience with tibial nailing in the extended position. Originally developed to address the complexities of alignment in proximal tibial fractures, this technique has also proven valuable in the treatment of tibial shaft fractures combined with ankle injuries. Depicted in this video presentation is the surgical techniques used to simultaneously address a spiral fracture of the distal tibia associated with a large coronal plane fracture of the tibial articular surface. Discussed are leg positioning, technical aspects of the medial approach, strategies for preliminary ankle stabilization, and fine details of aligning the tibial component of the injury. With a growing body of evidence suggesting similar knee outcomes with semiextended and conventional infrapatellar approaches, it is anticipated that this technique will become increasingly popular in coming years.

  8. Treatment of pathological humeral shaft fractures with intramedullary nailing. A retrospective study.

    Science.gov (United States)

    Pretell, Juan; Rodriguez, Juan; Blanco, David; Zafra, Alberto; Resines, Carlos

    2010-04-01

    A consecutive series of 22 pathological fractures of the humeral shaft in 21 patients treated at one institution were included in this retrospective study. Patients were treated with anterograde locked intramedullary nailing. Mean follow-up was 22.7 months (range 3-60). Mean VAS score improved from 89.5 (range 80-100) to 14.5 (range 0-40). In most patients there was a satisfactory return to daily activities within six weeks of surgery. Seventeen of 19 patients reported to be satisfied. Mean duration of hospitalization after surgery was 4.3 days (range 2-15). There were no complications related to the implants. There were no operative complications and the average operation time was 48 minutes (range 35-160). The consolidation rate was 80%. We emphasize that suspicion of fracture and interdisciplinary work between oncologists and orthopaedic surgeons are of crucial importance for survival time and individual treatment.

  9. Biomechanical performance of locked intramedullary nail systems in comminuted femoral shaft fractures.

    Science.gov (United States)

    Johnson, K D; Tencer, A F; Blumenthal, S; August, A; Johnston, D W

    1986-05-01

    The biomechanical properties of commercially available locked nail systems designed for use in comminuted femoral shaft fractures were compared and evaluated. Ender nails as well as three forms of interlocking nails, Brooker-Wills (B-W), Klenm-Schellman (K-S), and Grosse-Kempf (G-K), were implanted in cadaver femora. The femora were tested in torsion, bending, and axial loading to failure. Two fracture models were tested--a 3 cm subtrochanteric defect and an 8 cm midshaft defect. Results of the testing revealed the three interlocking nails to be comparable to each other and superior to Ender nails in bending and torsion. However, the distally bolted locked nails (K-S, G-K) resisted significantly higher loads than either the distally bladed locked nail (B-W) or Ender nails when tested to failure by axial loading.

  10. FATIGUE LIVES FOR INDUCTION HARDENED SHAFTS MATERIALS ACCORDING TO THE ENVIRONMENTAL TEMPERATURES

    Institute of Scientific and Technical Information of China (English)

    D.G. Lee; K.C.Jang; J.M. Kuk; I.S. Kim

    2005-01-01

    Rotary bending fatigue tests were carried out with two kinds of materials, S43C and S50C, using the front engine and front drive shaft (FF shaft) of vehicle. The specimens were induction hardened about 1.0mm depth from the specimen surface, and the hardness value on the surface was about HRC56-60. The tested environment temperatures were -30, 25 and 80℃ in order to look over effect of the induction hardening and the environmental temperatures on the fatigue characteristics. The fatigue limit of induction hardened specimens increased more about 45%than non-hardened specimens showing that the endurances of S43C and S50C were 98.1 and 107.9MPa in non-hardened samples, 147.1 and 156.9MPa in hardened samplesrespectably. The maximum tensile and compressive stress on the small circular defect was about +250 and -450MPa respectively when circular defect is situated on top and bottom. The fatigue life increased 80, 25and -30℃ in order regardless of hardening. In comparison of the fatigue lives on the basis of tested result at 25℃, the fatigue lives of non-hardened specimens decreased about 35%, but that of hardened specimens decreased about only 5% at 80℃ more than at 25℃. And fatigue life of non-hardened and hardened specimens were about 110% and 120% higher at -30℃ than that of 25℃. Based on the result of stress distribution near the defect, the tensile and compressive stress repeatedly generated by load direction were the largest on the small circular defect due to the stress concentration.

  11. Nonlinear Dynamic Modeling for a Diesel Engine Propeller Shafting Used in Large Marines

    Institute of Scientific and Technical Information of China (English)

    ZHANG Qinglei; DUAN Jianguo; ZHANG Suohuai; FU Yumin

    2014-01-01

    Longitudinal vibration, torsional vibration and their coupled vibration are the main vibration modes of the crankshaft-sliding bearing system. However, these vibrations of the propeller-crankshaft-sliding bearing system generated by the fluid exciting force on the propeller are much more complex. Currently, the torsional and longitudinal vibrations have been studied separately while the research on their coupled vibration is few, and the influence of the propeller structure to dynamic characteristics of a crankshaft has not been studied yet. In order to describe the dynamic properties of a crankshaft accurately, a nonlinear dynamic model is proposed taking the effect of torsional-longitudinal coupling and the variable inertia of propeller, connecting rod and piston into account. Numerical simulation cases are carried out to calculate the response data of the system in time and frequency domains under the working speed and over-speed, respectively. Results of vibration analysis of the propeller and crankshaft system coupled in torsional and longitudinal direction indicate that the system dynamic behaviors are relatively complicated especially in the components of the frequency response. For example, the 4 times of an exciting frequency acting on the propeller by fluid appears at 130 r/min, while not yield at 105 r/min. While the possible abnormal vibration at over-speed just needs to be vigilant. So when designing the propeller shafting used in marine diesel engines, strength calculation and vibration analysis based only on linear model may cause great errors and the proposed research provides some references to design diesel engine propeller shafting used in large marines.

  12. Comparative study between reamed versus unreamed interlocking intramedullary nailing in compound fractures of shaft tibia

    Directory of Open Access Journals (Sweden)

    Subhash Puri

    2013-01-01

    Full Text Available Background: Tibia is the commonest bones to sustain open injury because of subcutaneous position. Treatment of open fractures requires simultaneous management of both skeletal and soft tissue injury. Intramedullary nailing with reaming is generally considered to be contraindicated for open fractures tibia, because it damages the endosteal blood supply which will lead to non-union, deep infection. However, recent studies with or without reaming in open fracture tibia shows no influence in healing of fracture. Purpose: To compare the clinical and radiological results of intramedullary interlocking nailing of open fractures of the tibial shaft after reaming versus unreamed medullary canal. Materials and Methods: Between 2008 and 2011, we have treated 40 patients with compound tibia fracture (type I, II, IIIA by simultaneous care of wound and skeletal injury. Primary fixation for fracture stabilization was done by closed intramedullary interlock nailing either reamed or unreamed; the allocation to the two groups made on alternating basis. Wound was managed by thorough debridement with primary/delayed primary closure by suturing, split thickness skin grafting or fasciocutaneous flap cover. Active, non-weight bearing exercises were started from next post-op day. Partial weight bearing after suture removal was started on 12 th day. Further follow-up was done at 6 weeks interval for union. Results: Open fractures of shaft of tibia treated with unreamed/reamed interlocking nailing gave excellent results. In present series, 19 fractures (95% treated by unreamed and 19 (95% fractures treated by reamed technique, united within 6 months of injury. Delay in union was noticed in one patient treated by unreamed technique who had segmental and extensive soft tissue injury and in reamed nailing there was one patient with deep infection, which was treated with antibiotic coated nail. Conclusion: Time to complete union was similar in both groups. Adequate

  13. Dynamic Modeling of a Roller Chain Drive System Considering the Flexibility of Input Shaft

    Institute of Scientific and Technical Information of China (English)

    XU Lixin; YANG Yuhu; CHANG Zongyu; LIU Jianping

    2010-01-01

    Roller chain drives are widely used in various high-speed, high-load and power transmission applications, but their complex dynamic behavior is not well researched. Most studies were only focused on the analysis of the vibration of chain tight span, and in these models, many factors are neglected. In this paper, a mathematical model is developed to calculate the dynamic response of a roller chain drive working at constant or variable speed condition. In the model, the complete chain transmission with two sprockets and the necessary tight and slack spans is used. The effect of the flexibility of input shaft on dynamic response of the chain system is taken into account, as well as the elastic deformation in the chain, the inertial forces, the gravity and the torque on driven shaft. The nonlinear equations of movement are derived from using Lagrange equations and solved numerically. Given the center distance and the two initial position angles of teeth on driving and driven sprockets corresponding to the first seating roller on each side of the tight span, dynamics of any roller chain drive with two sprockets and two spans can be analyzed by the procedure. Finally, a numerical example is given and the validity of the procedure developed is demonstrated by analyzing the dynamic behavior of a typical roller chain drive. The model can well simulate the transverse and longitudinal vibration of the chain spans and the torsional vibration of the sprockets. This study can provide an effective method for the analysis of the dynamic characteristics of all the chain drive systems.

  14. ANTEGRADE INTRAMEDULLARY FIXATION OF HUMERAL SHAFT FRACTURES WITH INTERLOCKING NAIL - AN ANALYSIS OF COMPLICATIONS

    Directory of Open Access Journals (Sweden)

    Arvinder

    2013-11-01

    Full Text Available ABSTRACT : Fractures of the humeral shaft account for 3% of all the fractures . Primary cause of these fractures i s high energy traumas. Goals in managing these fractures are osseous union, minimal deformity and return of maximal extremity function. The union rate of simple fractures of humerus treated conservatively is over 90%. Surgical management of these fractures is preferred in Segmental fractures, Polytrauma patients, Pathological fractures, Open fractures , Failed conservative treatment, Associated progressive neurological deficit , Vascular injury, Morbid obesity. We analysed intraoperative and postoperative com plications in twelve patients with humeral shaft fractures managed with antegrade interlocking nails. There were seven males and five females. Their ages ranged between 20 – 60 years with an average of 32.6 years. There were 11 close and one Gustilo grade I open fractures. There were six comminuted , four transverse, and two oblique fractures. Nine fractures were in middle third one in proximal third and two in distal third. Five patients had associated injuries. We faced difficulty in localizing entry port al in 2 patients . There was difficulty in reduction in 2 patients We had one patient with iatrogenic comminution . Three patients had improper locking screw size. One had nail protrusion proximally , one patient had distraction at the fracture site . There we re two superficial entry portal skin infections and one deep proximal cross screw infection. We had two patients with shoulder and one patient with elbow stiffness. Chronic rotator cuff irritation was present in three patients. We recorded three delayed un ions, one nonunion and one rotatory malunion The results of the present study indicate that antegrade intramedullary interlocked nailing is one of the best method of treatment among the currently available methods.

  15. Fraturas da diáfise do úmero Humeral shaft fractures

    Directory of Open Access Journals (Sweden)

    Eduardo Benegas

    2010-01-01

    Full Text Available As fraturas da diáfise do úmero (FDU representam 3% das fraturas do aparelho locomotor; o terço médio da diáfise direita é o mais acometido. Seu tratamento é, na sua maioria, realizado por meio de métodos não cirúrgicos, mas as indicações cirúrgicas nas FDU são adotadas em situações cada vez mais frequentes. A diversidade de opiniões torna difícil o consenso sobre qual o tipo de osteossíntese, qual a técnica cirúrgica, a quantidade e a qualidade dos materiais de síntese a serem utilizados. Temos a impressão de que o melhor método para o tratamento cirúrgico das FDU está longe de ter um consenso entre os especialistas. Acreditamos que os métodos menos invasivos e que privilegiam a estabilidade relativa são os mais adequados, pois complicações mais temidas são menos frequentes.Humeral shaft fractures (HSF represent 3% of fractures of the locomotor apparatus, the mid-third section of the shaft being the most commonly affected. In the majority of cases, it is treated by non-surgical methods, but surgical indications in HSF are increasingly being adopted. The diversity of opinions makes it difficult to reach a consensus regarding to the type of osteosynthesis, surgical technique, and quantity and quality of the synthesis materials to be used. It would appear that specialists are far from reaching a consensus as to the best method for the surgical treatment of HSF. We believe that less invasive methods, which favor relative stability, are the most appropriate methods, as the most feared complications are less frequent.

  16. Quick determination of gas pressure before uncovering coal in cross-cuts and shafts

    Institute of Scientific and Technical Information of China (English)

    JIANG Cheng-lin; DENG Su-hua; ZHANG Chao-jie; CHENG Song-li; LV Shu-wen; WANG Chen; LI Xiao-wei; CHEN Yu-jia; XIE Qing-xue; LIU Ying; TANG Jun; YANG Fei-long; WANG Fa-kai

    2008-01-01

    The determination of gas pressure before uncovering coal in cross-cuts and in shafts is one of the important steps in predicting coal and gas outbursts. However, the time spent for testing gas pressure is, at present, very long, seriously affecting the application of outburst prediction techniques in opening coal seams in cross-cuts and shafts. In order to reduce the time needed in gas pressure tests and to improve the accuracy of tests, we analyzed the process of gas pressure tests and examined the effect of the length of boreholes in coal seams in tests. The result shows that 1) the shorter the borehole, the easier the real pressure value of gas can be obtained and 2) the main factors affecting the time spent in gas pressure tests are the length of the borehole in coal seams,the gas emission time after the borehole has been formed and the quality of the borehole-sealing. The longer the length of the borehole, the longer the gas emission time and the larger the pressure-relief circle formed around the borehole, the longer the time needed for pressure tests. By controlling the length of the borehole in a test case in the Huainan mining area, and adopting a quick sealing technique using a sticky liquid method, the sealing quality was clearly improved and the gas emission time as well as the amount of gas discharged greatly decreased. Before the method described, the time required for the gas pressure to increase during the pressure test process, was more than 10 days. With our new method the required time is only 5 hours. In addition, the accuracy of the gas pressure test is greatly improved.

  17. 毛干DNA提取方法概述%Review of Different DNA Extraction Methods in Hair Shafts

    Institute of Scientific and Technical Information of China (English)

    管政; 陈爱亮

    2012-01-01

    Hair shaft can be a valuable source of DNA for the noninvasive study of human and nonhuman populations because it' s easy to get, transport and store. However, hair shafts contain extremely small quantities of DNA but a large quantity of impurities like keratin and pigment, making the method used to extract the DNA of paramount importance. In order to provide sufficient documentation to help hair shaft DNA extraction, a review of recent 30 years literatures on procedures for obtaining DNA from hair shaft was presented and some conclusions for high efficiency DNA extraction in hair shaft were drawed.%毛干作为最容易取得的一种无创、运输和储存方便的生物样本,对从核酸分子水平上进行各方面研究有着十分重要的意义.但毛干中DNA含量低,不易提取,而且存在大量角蛋白和色素,纯化不净会对下游PCR扩增等反应产生抑制作用.基于毛干DNA提取现状,综述并比较了近三十年动物及人类毛发的毛干DNA提取、纯化等相关方法,拟为毛干DNA提取在分子生物学各领域的推广应用提供充分的文献支持和参考.

  18. Intramedullary nail versus dynamic compression plate fixation in treating humeral shaft fractures: grading the evidence through a meta-analysis.

    Directory of Open Access Journals (Sweden)

    JianXiong Ma

    Full Text Available There is a debate regarding the choice of operative intervention in humeral shaft fractures that require surgical intervention. The choices for operative interventions include intramedullary nailing (IMN and dynamic compression plate (DCP. This meta-analysis was performed to compare fracture union, functional outcomes, and complication rates in patients treated with IMN or DCP for humeral shaft fractures and to develop GRADE (Grading of Recommendations, Assessment, Development, and Evaluation-based recommendations for using the procedures to treat humeral shaft fractures. A systematic search of all the studies published through December 2012 was conducted using the Medline, Embase, Sciencedirect, OVID and Cochrane Central databases. The randomized controlled trials (RCTs and quasi-RCTs that compared IMN with DCP in treating adult patients with humeral shaft fractures and provided data regarding the safety and clinical effects were identified. The demographic characteristics, adverse events and clinical outcomes were manually extracted from all of the selected studies. Ten studies that included a total of 448 patients met the inclusion criteria. The results of a meta-analysis indicated that both IMN and DCP can achieve similar fracture union with a similar incidence of radial nerve injury and infection. IMN was associated with an increased risk of shoulder impingement, more restriction of shoulder movement, an increased risk of intraoperative fracture comminution, a higher incidence of implant failure, and an increased risk of re-operation. The overall GRADE system evidence quality was very low, which reduces our confidence in the recommendations of this system. DCP may be superior to IMN in the treatment of humeral shaft fractures. Because of the low quality evidence currently available, high-quality RCTs are required.

  19. EXPERIMENTAL ANALYSIS AND ISHIKAWA DIAGRAM FOR BURN ON EFFECT ON MANGANESE SILICON ALLOY MEDIUM CARBON STEEL SHAFT

    Directory of Open Access Journals (Sweden)

    AsmamawTegegne

    2013-12-01

    Full Text Available Burn on/metal penetration is one of the surface defects of metal castings in general and steel castings in particular. A research on the effect of burn on the six ton medium carbon steel shaft for making a roller of cold rolled steel sheet produced at one of the metals industry was carried out. The shaft was cast using sand casting by pouring through riser/feeding head step by step (with time interval of pouring. As it was required to use foam casting method for better surface finish and dimensional accuracy of the cast, the pattern was prepared from polystyrene and embedded by silica sand. Physical observations, photographic analysis, visual inspection, measurement of depth of penetration and fish bone diagram were used as method of results analysis. The shaft produced has strongly affected by sand sintering (burn on/metal penetration. Many reasons may be the case for these defects, however analysis results showed that the use of poorly designed gating system led to turbulence flow, uncontrollable high temperature fused the silica sand and liquid polystyrene penetrated the poorly reclaimed and rammed sand mold as a result of which eroded sand has penetrated the liquid metal deeply and reacted with it, consequently after solidification and finishing the required 240mm diameter of the shaft has reduced un evenly to 133mm minimum and 229mm maximum mm that end in the rejection of the shaft from the product since it is below the required standard for the designed application. In addition, it was not possible to remove the adhered sand by grinding. Thus burn on is included in mechanical type burn on.

  20. The Influence of a Mistuned Blade’s Staggle Angle on the Vibration and Stability of a Shaft-Disk-Blade Assembly

    Directory of Open Access Journals (Sweden)

    Yi-Jui Chiu

    2008-01-01

    Full Text Available The influence on coupling vibrations and stability among shaft-torsion, disk-transverse and blade-bending of a rotor system with a mistuned blade's staggle angle was investigated analytically. A shaft-disk-blade system has been found existing two types of coupling vibrations, disk-blade (DB, and blade-blade (BB modes when the shaft was assumed rigid. If the shaft's torsional flexibility was taken into account, an additional type of coupling modes, shaft-disk-blade (SDB, appeared. When an angle-mistuned blade existed, the blades periodicity was destroyed and it was found to change not only the natural frequencies but also the types of modes. Due to blade's mistune, the shaft torsion had to participate to balance such that DB modes vanished and replaced by SDB modes. A mistuned staggle angle was numerically found to alter the natural frequencies in an almost linear trend. At last, the rotational effects were found to merge frequency loci and eventually reached an instability point. Very interestingly, a mistuned blade diminished the possible instability caused by blade-dominating modes, which existed in a perfect and periodic rotor. In words, the rotor might benefit from a mistuned blade from the stability viewpoint. The shaft-dominating mode, yet, was unaffected by the mistune and retained a possible instability.

  1. 3000DWT成品油船轴系布置优化分析%Optimal Shafting Arrangement for 3000DWT Product Oil Tanker

    Institute of Scientific and Technical Information of China (English)

    李徐嘉; 张丹; 何小龙

    2015-01-01

    By analyzing three shafting arrangements and alignment results for 3000 DWT product oil tanker, the optimal shafting arrangement and design method for short shafting are proposed in this paper.%本文通过比较分析3000DWT成品油船三种不同的轴系布置方案、轴系校中计算结果,得出了最优布置方案和短轴系的布置方法。

  2. Study on Multi-bearings of Shipping Shaft System Alignment%船舶轴系校中多支承问题的研究

    Institute of Scientific and Technical Information of China (English)

    魏海军; 王宏志

    2001-01-01

    Shipping shaft system alignment is essential to ensuring the long-term's reliable operation of shaft.This paper studied multi-bearings of sterntube bearing using the transition matrix method of shipping shaft system alignment.%船舶轴系合理校中对保证轴系长期可靠运转极为重要。本文运用传递矩阵法对船舶轴系合理校中计算的多支承问题进行研究,从而进一步完善船舶轴系校中理论。

  3. 柔性转轴动力学分析与拍振现象%Dynamic Formulations and Beating Phenomena of Rotating Euler-Bernoulli Flexible Shafts

    Institute of Scientific and Technical Information of China (English)

    朱怀亮

    2002-01-01

    In this paper, the intrinsic behavior of rotating Euler-Benoulli flexible shafts was studied due to coupled bending and torsional vibrations. The equations of motion of the shaft with unbalanced eccentricity and viscous material damping were derived by the Hamilton principle. The numerical solution was obtained using the perturbation approach and mode-assuming method. The influences of the coupled vibrations between the bending and torsion, the rotating speed, material damping and the slenderness ratio of the shaft were analyzed. It is clearly shown that the beating phenomena can occur when the interaction of torsion and flexure is considered.

  4. Expert system for failure analysis of shafts; Sistema experto para analisis de falla de ejes

    Energy Technology Data Exchange (ETDEWEB)

    Jacobo Armendariz, V.H.; Cerrud Sanchez, S.M.; Ramirez Rodriguez, M.A.; Ortiz Prado, A. [Facultad de Ingenieria, UNAM, Mexico, D.F. (Mexico)

    2002-09-01

    An expert system for the failure analysis in metallic mechanical devices is being Developer at the Mechanical Engineering departments of the Faculty of Engineering of the Universidad Nacional Autonoma de Mexico (UNAM) to provide a solution for the failure analysis in cases where considerable experience in needed. The system pretends to resolve the scarceness of experts in the field of failure analysis and is oriented toward the metal-mechanics industry and will also have didactic applications. The main complication in the development of the system is the broad range of applications envisioned, like gears, shafts, bolts and springs between others. Therefore, it was decided to develop the system in a modular way, using the experience obtained in a first module to proceed faster in the others. The present paper presents the elaboration of the module that analyses shafts. This will serve as the base to expand the system toward other components. It uses the general structure of the global system, including an auxiliary software for the determination of maximum stresses in the corresponding parts. [Spanish] Con el fin de contar con un medio eficaz para la solucion de problemas relacionados con el analisis de falla, en donde la experiencia juega un papel fundamental, el Departamento de Ingenieria Mecanica de la Facultad de ingenieria de la Universidad Nacional Autonoma de Mexico (UNAM) , esta desarrollando el proyecto Sistema experto para analisis de falla de elementos mecanicos, dicho sistema busca resolver el inconveniente de la escasez de expertos y se orienta, tanto a la necesidad de la industria metalmecanica como a la de la docencia. Presenta tambien complicaciones en su desarrollo, ya que se pretende la posibilidad de realizar analisis de falla de elementos como ejes, engranes, pernos, bielas, resortes, tornillos etc. Por lo anterior, se establecio como estrategia el desarrollo del sistema por modulos, ya que teniendo la experiencia de elaboracion de un primer

  5. 冻结立井壁后出水分析及处理%Analysis and Treatment on Water Inflow f rom Backwall of Mine Shaft Liner in Mine Freezing Shaft

    Institute of Scientific and Technical Information of China (English)

    佟强; 杨广详; 孙德林; 杜丙启

    2014-01-01

    A mine ventilation shaft in the east block of Inner Mongolia Changcheng No.1 Mine was sunk with a ground freezing method.After an operation of a freezing machine stopped for one month,during a downward excavation conducted in a mine shaft,a water inflow occurred from a backwall of the mine shaft liner at the freezing section,a max water inflow was 60m3 /h and a safety construction was influenced. According to the analysis on the causes of the water inflow from the backwall of the mine shaft liner,a location of the water flow channel was found. Then a water detection and grouting borehole was drilled in the backwall,a chemical grouting material ——— Marithan E was applied to seal the water flow channel. The water inflow from the backwall was sealed within 5 days only and an ex pected effect was obtained.%内蒙长城一矿东区风井采用冻结法凿井。冻结停机1个月后,井筒向下掘进时,冻结段井壁后面出现涌水,涌水量最大达60 m3/h ,影响施工安全。根据对壁后出水原因的分析,找到了导水通道位置。然后施工壁后探水注浆孔,采用化学注浆材料马丽散E,对导水通道进行封堵;只用了5d ,就封堵住了壁后涌水,收到了预期效果。

  6. Implementation of preform-LCM process chain for the manufacturing of rotor hub shaft combination[Liquid Composite Molding

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2006-07-01

    Concept of a waste-free preform-liquid composite molding (LCM) process chain for the production of composite parts is developed and implemented for an integral lightweight construction with improvement in their ecological and economical properties. This also enables new applications for the composite materials. A prototype of rotor hub and shaft combination (HSC) of a horizontal axis wind turbine was designed and manufactured using integral components and composite materials. The aim of this study was to reduce the costs and weight in comparison with individual parts of standard metallic hub and shaft. This approach in the later stage facilitates to reduce the system costs of wind turbines. In this paper, the basic concept of the HSC component and the preform-LCM process chain used for its manufacturing is presented. Major advantageous features of preform and LCM technology for the large structures are described in detail. (au)

  7. An unconventional indication of the Sauve' - Kapandji procedure in a radial shaft pseudoarthrosis and chronic DRUJ dislocation: a case report.

    Science.gov (United States)

    Theodorakis, E; Fanelli, M; Ottolenghi, P; Pappalardo, S

    2013-01-01

    We present a 42-years-old male who developed a radial shaft pseudoartrosis and a chronic DRUJ dislocation/instability, following a Galeazzi fracture. He presented to our Office with a severe inability of wrist and forearm motion. A Sauve'-Kapandji procedure was adopted, performing a lateral approach to the ulna and grafting the excised ulnar block to retrieve radial length at the pseudoarthrosis level. Cancellous bone grafts from the iliac crest were also applied and mixed with autologous platelet rich plasma to promote callus formation. The goal was to create an intentional pseudoarthrosis of the distal ulna combined with a DRUJ arthrodesis, in order to resolve instability and regain forearm pronation/supination. We obtained bone healing, an excellent clinical recovery, and the patient returned to all his previous activities six months after surgery. To our knowledge, this is the first reported case of a radial shaft psudoarthrosis treated with the Sauve'-Kapandji technique.

  8. Investigation of the Influence Factors on Distortion in Induction-Hardened Steel Shafts Manufactured from Cold-Drawn Rod

    Science.gov (United States)

    Dong, Juan; Epp, Jeremy; Rocha, Alexandre da Silva; Nunes, Rafael Menezes; Zoch, Hans Werner

    2016-02-01

    In this study, the distortion of steel shafts was investigated before and after induction hardening. Several essential influencing factors in the manufacturing process chain regarding cold drawing, cutting method, notches on the shafts, and induction hardening were analyzed by design of experiment (DoE). Further necessary examinations of microstructures, hardness profile, segregation of chemical composition, and residual stress state were conducted for understanding the distortion behavior. The results of the statistical analysis of the DoE showed that the drawing process is the most important factor influencing distortion. The surface hardening depth of induction hardening is the second main factor. The relationship between inhomogeneities in the work pieces and the distortion was finally discussed.

  9. Renovation Application of Shafting Alignment Process%船舶轴系精确校中工艺工法

    Institute of Scientific and Technical Information of China (English)

    汪红兵; 金攀峰; 王友成; 张伟

    2013-01-01

    分析实船校中结果与校中计算偏差较大的几点原因,并创造性地提出一套校中方法,以实现从纸面到实质的合理轴系校中,减少振动,延长轴系使用寿命。%The reasons for the different between shaft alignment calculation and site alignment result are analyzed. One method to reduce the difference is creatively put forward,which is that the site alignment is closed to reason alignment, then the vibration reduces, the prolong service life of the shafting achieves.

  10. Development of a fixation device for robot assisted fracture reduction of femoral shaft fractures: a biomechanical study.

    Science.gov (United States)

    Weber-Spickschen, T S; Oszwald, M; Westphal, R; Krettek, C; Wahl, F; Gosling, T

    2010-01-01

    Robot assisted fracture reduction of femoral shaft fractures provides precise alignment while reducing the amount of intraoperative imaging. The connection between the robot and the fracture fragment should allow conventional intramedullary nailing, be minimally invasive and provide interim fracture stability. In our study we tested three different reduction tools: a conventional External Fixator, a Reposition-Plate and a Three-Point-Device with two variations (a 40 degrees and a 90 degrees version). We measured relative movements between the tools and the bone fragments in all translation and rotation planes. The Three-Point-Device 90 degrees showed the smallest average relative displacement and was the only device able to withstand the maximum applied load of 70 Nm without failure of any bone fragment. The Three-Point-Device 90 degrees complies with all the stipulated requirements and is a suitable interface for robot assisted fracture reduction of femoral shaft fractures.

  11. Estimation of shock loss factors at shaft bottom junction using computational fluid dynamics and scale model studies

    Energy Technology Data Exchange (ETDEWEB)

    Purushotham, T. [Alaska Univ., Fairbanks, AK (United States); Sastry, B.S.; Samanta, B. [Indian Inst. of Technology, Kharagpur (India)

    2010-07-01

    This article described the design of an effective ventilation system for underground mines that meets the air and pressure requirements of a mine. The distribution of the air quantity in the mine network is determined by the mine operating conditions and the characteristics of the mine fans. Shock losses generally account for 40 percent of the total pressure losses in mines. These losses must therefore be quantified for the different flow geometries found in mine ventilation systems. The shaft bottom junction in a mine ventilation system is an important source of shock loss due to the combined effect of bend and area change. Computational fluid dynamic techniques were used in this study examined the effects of the plat roughness and the shaft bottom length on the shock loss factor values. The results will be useful in designing effective air-crossings that minimize the amount of shock losses and reduce ventilation costs. 26 refs., 6 tabs., 6 figs.

  12. Rethinking the Business Model in Construction by the Use of Off-Site System Deliverance: Case of the Shaft Project

    DEFF Research Database (Denmark)

    Thuesen, Christian; Hvam, Lars

    2013-01-01

    in the existing design and production practices. More specifically the development of system deliveries requires: (1) an explicit market focus, enabling the achievement of economy of scale, (2) a coordinated and coherent development around the system deliverance focusing on its internal and external modularity...... of installation shafts. Findings from the development and production of the installation shaft show that system deliveries represent a promising strategy for moving from red ocean competitive environment with the predominant cost+ business model, to a blue ocean situation in which the competition emerges....... (3) development of processes and configuration practices which make it possible to put together (configure) the product matching the needs of the individual building project. (4) development of alliances between companies in enabling value chain integration....

  13. Forming of Hollow Shaft Forging From Titanium Alloy Ti6Al4V by Means of Rotary Compression

    Directory of Open Access Journals (Sweden)

    Tomczak J.

    2015-04-01

    Full Text Available This paper presents chosen results of theoretical-experimental works concerning forming of hollow shafts forgings from titanium alloys, which are applied in aviation industry. At the first stage of conducted analysis, the forging forming process was modeled by means of finite element method. Calculations were made using software Simufact Forming. On the basis of performed simulations optimal parameters of rotary compression process were determined. Next, experimental tests of forging forming in laboratory conditions were made. For the research needs, a forging aggregate, designed by the Authors, was used. Conducted research works confirmed the possibility of metal forming (by means of rotary compression of hollow shafts from hard workable titanium alloys. Numerous advantages of rotary compression process, make it attractive both for low series production (aircraft industry and for mass production (automotive industry.

  14. Synchronous motor with soft start element formed between the motor rotor and motor output shaft to successfully synchronize loads that have high inertia and/or high torque

    Energy Technology Data Exchange (ETDEWEB)

    Umans, Stephen D; Nisley, Donald L; Melfi, Michael J

    2014-10-28

    A line-start synchronous motor has a housing, a rotor shaft, and an output shaft. A soft-start coupling portion is operatively coupled to the output shaft and the rotor shaft. The soft-start coupling portion is configurable to enable the synchronous motor to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling. The synchronous motor is sufficiently rated to obtain synchronous operation and to drive, at least near synchronous speed during normal steady state operation of the motor, a load having characteristics sufficient to prevent obtaining normal synchronous operation of the motor when the motor is operatively connected to the load in the absence of the soft-start coupling.

  15. 艉轴轴系中心线的调正与端面密封%Stern Shaft Centerline Alignment and Sealing Device

    Institute of Scientific and Technical Information of China (English)

    周立彬; 赵利家; 陈焕国

    2011-01-01

    艉轴作为船舶传递动力的装置,是极其重要的零件,因此在其轴系中心线调正时选用正确的方法,并选用合适的艉轴端面密封的方式尤为重要.介绍了轴系中心线调正方法和要求,以及艉轴承端面密封的要求与工艺.%Stem shaft is one of the most important parts in marina transmission. So it is necessary to use the correct method and to choose the appropriate stem shaft seal method In the shaft centerline alignment. It also introduces the shaft centeriine alignment methods and sealing device of stem bearings.

  16. TO THE QUESTION ABOUT THE INFLUENCE OF THE STRESSES IN THE ELEMENTS OF THE REINFORCEMENT SHAFTS AT THE RATE OF CORROSION

    Directory of Open Access Journals (Sweden)

    V. V. Kovalenko

    2008-03-01

    Full Text Available On the basis of laboratory explorations the features of conducting the corrosive process in the shaft reinforcement parts under the load from lifting buckets and rock mass were determined.

  17. 细长轴车削加工工艺%The slender shaft turning processing technology

    Institute of Scientific and Technical Information of China (English)

    李铭勳

    2014-01-01

    In this paper, factors influencing the machining parts precision slender shaft is not high, analyzes how to raise processing precision of slender axle parts, gives the specific methods to solve the problem.%文章针对影响加工细长轴零件精度不高等因素,分析了如何提细长轴零件的加工精度,给出解决问题的具体方法。

  18. Microwave ablation: results in ex vivo and in vivo porcine livers with 2450-MHz cooled-shaft antenna

    Institute of Scientific and Technical Information of China (English)

    ZHOU Qi; JIN Xing; JIAO De-chao; ZHANG Fu-jun; ZHANG Liang; HAN Xin-wei; DUAN Guang-feng; LI Chuan-xing; HAN Jian-jun

    2011-01-01

    Background Imaging-guided thermal ablation using different energy sources continues to gain favor as a minimally invasive technique for the treatment of primary and metastatic hepatic malignant tumors.This study aimed to evaluate the performance of microwave ablation with 2450-MHz internally cooled-shaft antenna in ex vivo and in vivo porcine livers.Methods All studies were animal care and ethics committee approved.Microwave ablation was performed using a noncooled or cooled-shaft antenna in 23 ex vivo (92 ablations) and eight in vivo (36 ablations) porcine livers.Diameters of the coagulation zone were observed on gross specimens.The coagulation diameters achieved in different microwave ablation parameter groups were compared.Curve estimation analysis was performed to characterize the relationship between applied power and treatment duration and coagulation diameter (including short-axis and long-axis diameter).Results Coagulation zones were elliptical and an arrowed-shaped carbonization zone around the shaft was observed in all groups.But the antenna track was also coagulated in the noncooled-shaft antenna groups.In ex vivo livers,the short-axis diameter correlated with the power output in a quadratic curve fashion (R2=0.95) by fixing ablation duration to 10 minutes,and correlated with the ablation duration in a logarithmic curve fashion (R2=0.98) by fixing power output to 80 W.The short-axis reached a relative plateau within 25 minutes.In in vivo livers,short-axis diameter correlated with the coagulation duration in a sigmoidal curve fashion (60 W group R2=0.76,80 W group R2=0.87),with a relative plateau achieved within 10 minutes for power settings of 60 W and 80 W.Conclusions The internally cooled microwave antenna may be advantageous to minimize collateral damage.The short-axis diameter enlargement has a plateau by fixing power output.

  19. Whole shaft visibility and mechanical performance for active MR catheters using copper-nitinol braided polymer tubes

    Directory of Open Access Journals (Sweden)

    McVeigh Elliot R

    2009-08-01

    Full Text Available Abstract Background Catheter visualization and tracking remains a challenge in interventional MR. Active guidewires can be made conspicuous in "profile" along their whole shaft exploiting metallic core wire and hypotube components that are intrinsic to their mechanical performance. Polymer-based catheters, on the other hand, offer no conductive medium to carry radio frequency waves. We developed a new "active" catheter design for interventional MR with mechanical performance resembling braided X-ray devices. Our 75 cm long hybrid catheter shaft incorporates a wire lattice in a polymer matrix, and contains three distal loop coils in a flexible and torquable 7Fr device. We explored the impact of braid material designs on radiofrequency and mechanical performance. Results The incorporation of copper wire into in a superelastic nitinol braided loopless antenna allowed good visualization of the whole shaft (70 cm in vitro and in vivo in swine during real-time MR with 1.5 T scanner. Additional distal tip coils enhanced tip visibility. Increasing the copper:nitinol ratio in braiding configurations improved flexibility at the expense of torquability. We found a 16-wire braid of 1:1 copper:nitinol to have the optimum balance of mechanical (trackability, flexibility, torquability and antenna (signal attenuation properties. With this configuration, the temperature increase remained less than 2°C during real-time MR within 10 cm horizontal from the isocenter. The design was conspicuous in vitro and in vivo. Conclusion We have engineered a new loopless antenna configuration that imparts interventional MR catheters with satisfactory mechanical and imaging characteristics. This compact loopless antenna design can be generalized to visualize the whole shaft of any general-purpose polymer catheter to perform safe interventional procedures.

  20. 鼓风机轴断裂失效分析%Fracture failure analysis of blower shaft

    Institute of Scientific and Technical Information of China (English)

    王若民; 陈国宏; 施鹏; 缪春辉

    2016-01-01

    In order to find out the fracture reason of the imported blower shaft in a thermal power generating unit, methods of macro-observation, chemical composition analysis, metallographic examination, spectrum analysis, mechanical properties test and microhardness test were used to analyze the failure shaft. The results show that the main reason for the high cycle fatigue fracture of the shaft is due to abnormal secondary quenching, which results in the generation of harmful microstructure such as hardy and brittle quenched martensite and massive soft ferrite along the shaft neck.%针对某火力发电机组进口鼓风机主轴断裂问题,采用宏观断口分析、化学成分分析、金相分析、能谱分析、力学性能和显微硬度检测等手段对其断裂原因进行了分析。结果表明:轴断裂的主要原因是由于异常的二次淬火导致轴颈基体表面形成硬而脆的粗大淬火马氏体和软化的块状铁素体等不良组织,降低了轴颈处的抗疲劳性能,运行过程中在高周交变应力作用下发生疲劳断裂。