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Sample records for injection moulding parameters

  1. Characterisation of demoulding parameters in micro‑injection moulding

    DEFF Research Database (Denmark)

    Griffiths, C.A.; Tosello, Guido; Dimov, S.S.

    2015-01-01

    on the process factors that affect parts’ quality. Using a Cyclic Olefin Copolyme (COC) microfluidics demonstrator, the demoulding performance was studied as a function of four process parameters (melt temperature, mould temperature, holding pressure and injection speed), employing the design of experiment...

  2. Optimization of injection moulding process parameters in the ...

    African Journals Online (AJOL)

    In this study, optimal injection moulding conditions for minimum shrinkage during moulding of High Density Polyethylene (HDPE) were obtained by Taguchi method. The result showed that melting temperature of 190OC, injection pressure of 55 MPa, refilling pressure of 85 MPa and cooling time of 11 seconds gave ...

  3. Optimization of Injection Moulding Process Parameters in the ...

    African Journals Online (AJOL)

    ADOWIE PERE

    https://www.ajol.info/index.php/jasem ... Cooling time was found to be the factor with most significant effect on ... Keywords: High Density Polyethylene (HDPE), Injection Moulding, Process .... value of shrinkage behavior is expected to be.

  4. Effect of process parameters on flow length and flash formation in injection moulding of high aspect ratio polymeric micro features

    DEFF Research Database (Denmark)

    Eladl, Abdelkhalik; Mostafa, Rania; Islam, Aminul

    2018-01-01

    This paper reports an investigation of the effects of process parameters on the quality characteristics of polymeric parts produced by micro injection moulding (µIM) with two different materials. Four injection moulding process parameters (injection velocity, holding pressure, melt temperature an...

  5. Effect of Process Parameters on Flow Length and Flash Formation in Injection Moulding of High Aspect Ratio Polymeric Micro Features

    Directory of Open Access Journals (Sweden)

    Abdelkhalik Eladl

    2018-01-01

    Full Text Available This paper reports an investigation of the effects of process parameters on the quality characteristics of polymeric parts produced by micro injection moulding (μIM with two different materials. Four injection moulding process parameters (injection velocity, holding pressure, melt temperature and mould temperature were investigated using Polypropylene (PP and Acrylonitrile Butadiene Styrene (ABS. Three key characteristics of the mouldings were evaluated with respect to process settings and the material employed: part mass, flow length and flash formation. The experimentation employs a test part with four micro fingers with different aspect ratios (from 21 up to 150 and was carried out according to the Design of Experiments (DOE statistical technique. The results show that holding pressure and injection velocity are the most influential parameters on part mass with a direct effect for both materials. Both parameters have a similar effect on flow length for both PP and ABS at all aspect ratios and have higher effects as the feature thickness decreased below 300 μm. The study shows that for the investigated materials the injection speed and packing pressure were the most influential parameters for increasing the amount of flash formation, with relative effects consistent for both materials. Higher melt and mould temperatures settings were less influential parameters for increasing the flash amount when moulding with both materials. Of the two investigated materials, PP was the one exhibiting more flash formation as compared with ABS, when corresponding injection moulding parameters settings for both materials were considered.

  6. Study of process parameters effect on the filling phase of micro injection moulding using weld lines as flow markers

    DEFF Research Database (Denmark)

    Tosello, Guido; Gava, Alberto; Hansen, Hans Nørgaard

    2010-01-01

    , the relationships between the filling pattern and the different process parameter settings have to be established. In this paper, a novel approach based on the use of weld lines as flow markers to trace the development of the flow front during the filling is proposed. The effects on the filling stage of process......Micro-injection moulding (micro-moulding) is a process which enables the mass production of polymer microproducts. In order to produce high-quality injection moulded micro-parts, a crucial aspect to be fully understood and optimised is the filling of the cavity by the molten polymer. As a result...... manufactured by micro-electrodischarge machining. A commercially available polystyrene grade polymer has been moulded using a high-speed injection moulding machine. The design of experiment technique was employed to determine the effect of the process parameters on the filling phase of the micro...

  7. Injection moulding antireflective nanostructures

    DEFF Research Database (Denmark)

    Christiansen, Alexander Bruun; Clausen, Jeppe Sandvik; Mortensen, N. Asger

    2014-01-01

    We present a method for injection moulding antireflective nanostructures on large areas, for high volume production. Nanostructured black silicon masters were fabricated by mask-less reactive ion etching, and electroplated with nickel. The nickel shim was antistiction coated and used in an inject......We present a method for injection moulding antireflective nanostructures on large areas, for high volume production. Nanostructured black silicon masters were fabricated by mask-less reactive ion etching, and electroplated with nickel. The nickel shim was antistiction coated and used...

  8. Injection moulding antireflective nanostructures

    DEFF Research Database (Denmark)

    Christiansen, Alexander Bruun; Clausen, Jeppe Sandvik; Mortensen, N. Asger

    We present a method for injection moulding antireflective nanostructures on large areas, for high volume production. Nanostructured black silicon masters were fabricated by mask-less reactive ion etching, and electroplated with nickel. The nickel shim was antistiction coated and used in an inject......We present a method for injection moulding antireflective nanostructures on large areas, for high volume production. Nanostructured black silicon masters were fabricated by mask-less reactive ion etching, and electroplated with nickel. The nickel shim was antistiction coated and used...

  9. Examination of injection moulded thermoplastic maize starch

    Directory of Open Access Journals (Sweden)

    2007-12-01

    Full Text Available This paper focuses on the effect of the different injection moulding parameters and storing methods on injection moulded thermoplastic maize starch (TPS. The glycerol and water plasticized starch was processed in a twin screw extruder and then with an injection moulding machine to produce TPS dumbbell specimens. Different injection moulding set-ups and storing conditions were used to analyse the effects on the properties of thermoplastic starch. Investigated parameters were injection moulding pressure, holding pressure, and for the storage: storage at 50% relative humidity, and under ambient conditions. After processing the mechanical and shrinkage properties of the manufactured TPS were determined as a function of the ageing time. While conditioning, the characteristics of the TPS changed from a soft material to a rigid material. Although this main behaviour remained, the different injection moulding parameters changed the characteristics of TPS. Scanning electron microscope observations revealed the changes in the material on ageing.

  10. Surface Micro Topography Replication in Injection Moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Kjær, Erik Michael

    2005-01-01

    The surface micro topography of injection moulded plastic parts can be important for aesthetical and technical reasons. The quality of replication of mould surface topography onto the plastic surface depends among other factors on the process conditions. A study of this relationship has been...... carried out with rough EDM (electrical discharge machining) mould surfaces, a PS grade, and by applying established three-dimensional topography parameters. Significant quantitative relationships between process parameters and topography parameters were established. It further appeared that replication...

  11. Computational design of mould sprue for injection moulding thermoplastics

    Directory of Open Access Journals (Sweden)

    Muralidhar Lakkanna

    2016-01-01

    Full Text Available To injection mould polymers, designing mould is a key task involving several critical decisions with direct implications to yield quality, productivity and frugality. One prominent decision among them is specifying sprue-bush conduit expansion as it significantly influences overall injection moulding; abstruseness anguish in its design criteria deceives direct determination. Intuitively designers decide it wisely and then exasperate by optimising or manipulating processing parameters. To overwhelm that anomaly this research aims at proposing an ideal design criteria holistically for all polymeric materials also tend as a functional assessment metric towards perfection i.e., criteria to specify sprue conduit size before mould development. Accordingly, a priori analytical criterion was deduced quantitatively as expansion ratio from ubiquitous empirical relationships specifically a.k.a an exclusive expansion angle imperatively configured for injectant properties. Its computational intelligence advantage was leveraged to augment functionality of perfectly injecting into an impression gap, while synchronising both injector capacity and desired moulding features. For comprehensiveness, it was continuously sensitised over infinite scale as an explicit factor dependent on in-situ spatio-temporal injectant state perplexity with discrete slope and altitude for each polymeric character. In which congregant ranges of apparent viscosity and shear thinning index were conceived to characteristically assort most thermoplastics. Thereon results accorded aggressive conduit expansion widening for viscous incrust, while a very aggressive narrowing for shear thinning encrust; among them apparent viscosity had relative dominance. This important rationale would certainly form a priori design basis as well diagnose filling issues causing several defects. Like this the proposed generic design criteria, being simple would immensely benefit mould designers besides serve

  12. Demoulding force in micro-injection moulding

    DEFF Research Database (Denmark)

    Griffiths, C.A.; Dimov, S.S.; Scholz, S.

    2012-01-01

    The paper reports an experimental study that investigates part demoulding behavior in micro injection moulding (MIM) with a focus on the effects of pressure (P) and temperature (T) on the demoulding forces. Demoulding of a microfluidics part is conducted and the four processing parameters of melt...... temperature (Tb), mould temperature (Tm), holding pressure (Ph) and injection speed (Vi) are analysed. The result using different combinations of process parameters were used to identify the best processing conditions in regards to demoulding forces when moulding micro parts....

  13. Micro Injection Moulding

    DEFF Research Database (Denmark)

    Kjær, Erik Michael; Johansen, Bjørn B.; Sørensen, Hans H.

    2000-01-01

    Microstructures were created in SiO2 wafers using RIE and KOH etching. The mould inserts was manufactured by Ni electroplating the wafers. Different types of microstructures were made in the mould; rows of quadratic columns, rows of pyramids and of pyramid stumps. The structures (from the SiO2...

  14. Process Condition Monitoring of Micro Moulding Using a Two-plunger Micro Injection Moulding Machine

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Guerrier, Patrick

    2010-01-01

    The influence of micro injection moulding (µIM) process parameters (melt and mould temperature, piston injection speed and stoke length) on the injection pressure was investigated using Design of Experiments. Direct piston injection pressure measurements were performed and data collected using...... a micro injection moulding machine equipped with a two-pluger injection unit. Miniaturized dog-bone shaped speciments on polyoxymethylene (POM) were moulded over a wide range of processing cpnditions in order to characterize the process and assess its capability. Experimental results obtained under...

  15. Cavity Pressure Behaviour in Micro Injection Moulding

    DEFF Research Database (Denmark)

    Griffiths, C.A.; Dimov, S.S.; Scholz, S.

    2010-01-01

    as well as with the filling of the cavity by the polymer melt. In this paper, two parameters derived from cavity pressure over time (i.e. pressure work). The influence of four µIM parameters (melt temperature, mould temperature, injection speed, aand packing pressure) on the two pressure-related outputs...... has been investigated by moulding a micro fluidic component on three different polymers (PP, ABS, PC) using the design of experiment approach. Similar trends such as the effects of a higher injection speed in decreasing the pressure work and of a lower temperature in decreasing pressure rate have been......Process monitoring of micro injection moulding (µIM) is of crusial importance to analyse the effect of different parameter settings on the process and to assess its quality. Quality factors related to cavity pressure can provide useful information directly connected with the dyanmics of the process...

  16. Investigation of process parameters influence on flash formation in injection moulding of polymer micro features through design of experiments

    DEFF Research Database (Denmark)

    Eladl, Abdelkhalik; Tosello, Guido; Mostafa, Rania

    Micro injection moulding is one of the key technologies for micro manufacture due to its mass-production capability and relatively low component cost. Flash defects are among the most critical issues in the replication of micro features and constitute a manufacturing constrain in applying injecti...

  17. Injection moulding of optical functional micro structures using laser structured, PVD-coated mould inserts

    Energy Technology Data Exchange (ETDEWEB)

    Hopmann, Ch.; Weber, M.; Schöngart, M.; Schäfer, C., E-mail: weber@ikv-aachen.de [Institute of Plastics Processing (IKV) at RWTH Aachen University (Germany); Bobzin, K.; Bagcivan, N.; Brögelmann, T.; Theiß, S.; Münstermann, T. [Surface Engineering Institute (IOT), RWTH Aachen University, Aachen (Germany); Steger, M. [Fraunhofer Institute for Laser Technology (ILT), Aachen (Germany)

    2015-05-22

    Micro structured optical plastics components are intensively used i. e. in consumer electronics, for optical sensors in metrology, innovative LED-lighting or laser technology. Injection moulding has proven to be successful for the large-scale production of those parts. However, the production of those parts still causes difficulties due to challenges in the moulding and demoulding of plastics parts created with laser structured mould inserts. A complete moulding of the structures often leads to increased demoulding forces, which then cause a breaking of the structures and a clogging of the mould. An innovative approach is to combine PVD-coated (physical vapour deposition), laser structured inserts and a variothermal moulding process to create functional mic8iüro structures in a one-step process. Therefore, a PVD-coating is applied after the laser structuring process in order to improve the wear resistance and the anti-adhesive properties against the plastics melt. In a series of moulding trials with polycarbonate (PC) and polymethylmethacrylate (PMMA) using different coated moulds, the mould temperature during injection was varied in the range of the glass transition and the melt temperature of the polymers. Subsequently, the surface topography of the moulded parts is evaluated by digital 3D laser-scanning microscopy. The influence of the moulding parameters and the coating of the mould insert on the moulding accuracy and the demoulding behaviour are being analysed. It is shown that micro structures created by ultra-short pulse laser ablation can be successfully replicated in a variothermal moulding process. Due to the mould coating, significant improvements could be achieved in producing micro structured optical plastics components.

  18. Warpage analysis in injection moulding process

    Science.gov (United States)

    Hidayah, M. H. N.; Shayfull, Z.; Nasir, S. M.; Fathullah, M.; Hazwan, M. H. M.

    2017-09-01

    This study was concentrated on the effects of process parameters in plastic injection moulding process towards warpage problem by using Autodesk Moldflow Insight (AMI) software for the simulation. In this study, plastic dispenser of dental floss has been analysed with thermoplastic material of Polypropylene (PP) used as the moulded material and details properties of 80 Tonne Nessei NEX 1000 injection moulding machine also has been used in this study. The variable parameters of the process are packing pressure, packing time, melt temperature and cooling time. Minimization of warpage obtained from the optimization and analysis data from the Design Expert software. Integration of Response Surface Methodology (RSM), Center Composite Design (CCD) with polynomial models that has been obtained from Design of Experiment (DOE) is the method used in this study. The results show that packing pressure is the main factor that will contribute to the formation of warpage in x-axis and y-axis. While in z-axis, the main factor is melt temperature and packing time is the less significant among the four parameters in x, y and z-axes. From optimal processing parameter, the value of warpage in x, y and z-axis have been optimised by 21.60%, 26.45% and 24.53%, respectively.

  19. Two Component Injection Moulding for Moulded Interconnect Devices

    DEFF Research Database (Denmark)

    Islam, Aminul

    component (2k) injection moulding is one of the most industrially adaptive processes. However, the use of two component injection moulding for MID fabrication, with circuit patterns in sub-millimeter range, is still a big challenge. This book searches for the technical difficulties associated...... with the process and makes attempts to overcome those challenges. In search of suitable polymer materials for MID applications, potential materials are characterized in terms of polymer-polymer bond strength, polymer-polymer interface quality and selective metallization. The experimental results find the factors...... which can effectively control the quality of 2k moulded parts and metallized MIDs. This book presents documented knowledge about MID process chains, 2k moulding and selective metallization which can be valuable source of information for both academic and industrial users....

  20. Two component micro injection moulding for moulded interconnect devices

    DEFF Research Database (Denmark)

    Islam, Aminul

    2008-01-01

    Moulded interconnect devices (MIDs) contain huge possibilities for many applications in micro electro-mechanical-systems because of their capability of reducing the number of components, process steps and finally in miniaturization of the product. Among the available MID process chains, two...... component injection moulding is one of the most industrially adaptive processes. However, the use of two component injection moulding for MID fabrication, with circuit patterns in the sub-millimeter range, is still a big challenge at the present state of technology. The scope of the current Ph.D. project...... and a reasonable adhesion between them. • Selective metallization of the two component plastic part (coating one polymer with metal and leaving the other one uncoated) To overcome these two main issues in MID fabrication for micro applications, the current Ph.D. project explores the technical difficulties...

  1. Surface Microstructure Replication in Injection Moulding

    DEFF Research Database (Denmark)

    Hansen, Hans Nørgaard; Arlø, Uffe Rolf

    2005-01-01

    topography is transcribed onto the plastic part through complex mechanisms. This replication however, is not perfect, and the replication quality depends on the plastic material properties, the topography itself, and the process conditions. This paper describes and discusses an investigation of injection...... moulding of surface microstructures. Emphasis is put on the ability to replicate surface microstructures under normal injection moulding conditions, notably with low cost materials at low mould temperatures. The replication of surface microstructures in injection moulding has been explored...... for Polypropylene at low mould temperatures. The process conditions were varied over the recommended process window for the material. The geometry of the obtained structures was analyzed. Evidence suggests that step height replication quality depends linearly on structure width in a certain range. Further...

  2. Injection moulding for macro and micro products

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul

    used for macro products but with the ages it is going deep into the micro areas having machine and process improvements. Extensive research work on injection moulding is going on all over the world. New ideas are flowing into the machines, materials and processes. The technology has made significant......The purpose of the literature survey is to investigate the injection moulding technology in the macro and micro areas from the basic to the state-of-the-art recent technology. Injection moulding is a versatile production process for the manufacturing of plastic parts and the process is extensively...

  3. Micro-powder injection moulding of tungsten

    International Nuclear Information System (INIS)

    Zeep, B.

    2007-12-01

    For He-cooled Divertors as integral components of future fusion power plants, about 300000 complex shaped tungsten components are to be fabricated. Tungsten is the favoured material because of its excellent properties (high melting point, high hardness, high sputtering resistance, high thermal conductivity). However, the material's properties cause major problems for large scale production of complex shaped components. Due to the resistance of tungsten to mechanical machining, new fabrication technologies have to be developed. Powder injection moulding as a well established shaping technology for a large scale production of complex or even micro structured parts might be a suitable method to produce tungsten components for fusion applications but is not yet commercially available. The present thesis is dealing with the development of a powder injection moulding process for micro structured tungsten components. To develop a suitable feedstock, the powder particle properties, the binder formulation and the solid load were optimised. To meet the requirements for a replication of micro patterned cavities, a special target was to define the smallest powder particle size applicable for micro-powder injection moulding. To investigate the injection moulding performance of the developed feedstocks, experiments were successfully carried out applying diverse cavities with structural details in micro dimension. For debinding of the green bodies, a combination of solvent debinding and thermal debinding has been adopted for injection moulded tungsten components. To develop a suitable debinding strategy, a variation of the solvent debinding time, the heating rate and the binder formulation was performed. For investigating the thermal consolidation behaviour of tungsten components, sinter experiments were carried out applying tungsten powders suitable for micro-powder injection moulding. First mechanical tests of the sintered samples showed promising material properties such as a

  4. Surface micro topography replication in injection moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf

    Thermoplastic injection moulding is a widely used industrial process that involves surface generation by replication. The surface topography of injection moulded plastic parts can be important for aesthetical or technical reasons. With the emergence of microengineering and nanotechnology additional...... importance of surface topography follows. In general the replication is not perfect and the topography of the plastic part differs from the inverse topography of the mould cavity. It is desirable to be able to control the degree of replication perfection or replication quality. This requires an understanding...... of the physical mechanisms of replication. Such understanding can lead to improved process design and facilitate in-line process quality control with respect to surface properties. The purpose of the project is to identify critical factors that affect topography replication quality and to obtain an understanding...

  5. Process Optimization for Injection Moulding of Passive Microwave Components

    DEFF Research Database (Denmark)

    Scholz, Steffen G.; Mueller, Tobias; Santos Machado, Leonardo

    2016-01-01

    The demand for micro components has increased during the last decade following the overall trend towards miniaturization. Injection moulding is the favoured technique for the mass manufacturing of micro components or larger parts with micro-structured areas due to its ability to cost effectively ...... algorithm for modelling, the influence of different moulding parameters on the final part quality was assessed. Firstly a process model and secondly a quality model has been calculated. The results shows that part quality can be controlled by monitoring characteristic numbers....

  6. Quality control of injection moulded micro mechanical parts

    DEFF Research Database (Denmark)

    Gasparin, Stefania; Tosello, Guido; Hansen, Hans Nørgaard

    2009-01-01

    Quality control of micro components is an increasing challenge. Smaller mechanical parts are characterized by smaller tolerance to be verified. This paper focuses on the dimensional verification of micro injection moulded components selected from an industrial application. These parts are measured...... using an Optical Coordinate Measuring Machine (OCMM), which guarantees fast surface scans suitable for in line quality control. The uncertainty assessment of the measurements is calculated following the substitution method. To investigate the influence parameters in optical coordinate metrology two...

  7. Exercise in injection moulding: Predicting the non-uniform shrinkage from PVT data

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Koblitz; Eriksson, Torbjörn Gerhard

    Injection moulding is a widely spread technique for producing plastic parts of many kinds, for example bowls, chairs, coverings for mobile phones etc. The basic principle of injection moulding is to inject molten plastic into a closed, cooled mould (i. e. tool), where it solidifies to give......) is manufactured using two types of commercial plastics (Polypropylene (PP) and Polycarbonate (PC)). Pressure transducers measure the pressure in the mould during the injection and the solidification. The temperature is measured by inserting a thermometer in the plastic melt. The difference in dimensions between...... the product. The product is recovered by opening the mould to release it. The quality of the product is highly dependent on tool design, process parameters such as pressure and temperature and which type of polymer that is used. Here, a plastic bar with four indentions (in the form of parallel lines...

  8. Compression and Injection Moulding of Nano-Structured Polymer Surfaces

    DEFF Research Database (Denmark)

    Pranov, Henrik; Rasmussen, Henrik Koblitz

    2006-01-01

    In our research we investigate the non-isothermal replication of complex nano and micro surface structures in injection and compression moulding.......In our research we investigate the non-isothermal replication of complex nano and micro surface structures in injection and compression moulding....

  9. Improving the accuracy of micro injection moulding process simulations

    DEFF Research Database (Denmark)

    Marhöfer, David Maximilian; Tosello, Guido; Islam, Aminul

    and are therefore limited in the capability of modelling the polymer flow in micro cavities. Hence, new strategies for comprehensive simulation models which provide more precise results open up new opportunities and will be discussed. Modelling and meshing recommendations are presented, leading to a multi......Process simulations in micro injection moulding aim at the optimization and support of the design of the mould, mould inserts, the plastic product, and the process. Nevertheless, dedicated software packages for micro injection moulding are not available. They are developed for macro plastic parts...

  10. Optimisation of warpage on plastic injection moulding part using response surface methodology (RSM) and genetic algorithm method (GA)

    Science.gov (United States)

    Miza, A. T. N. A.; Shayfull, Z.; Nasir, S. M.; Fathullah, M.; Hazwan, M. H. M.

    2017-09-01

    In this study, Computer Aided Engineering was used for injection moulding simulation. The method of Design of experiment (DOE) was utilize according to the Latin Square orthogonal array. The relationship between the injection moulding parameters and warpage were identify based on the experimental data that used. Response Surface Methodology (RSM) was used as to validate the model accuracy. Then, the RSM and GA method were combine as to examine the optimum injection moulding process parameter. Therefore the optimisation of injection moulding is largely improve and the result shown an increasing accuracy and also reliability. The propose method by combining RSM and GA method also contribute in minimising the warpage from occur.

  11. Low pressure powder injection moulding of stainless steel powders

    Energy Technology Data Exchange (ETDEWEB)

    Zampieron, J.V.; Soares, J.P.; Mathias, F.; Rossi, J.L. [Powder Processing Center CCP, Inst. de Pesquisas Energeticas e Nucleares, Sao Paulo, SP (Brazil); Filho, F.A. [IPEN, Inst. de Pesquisas Energeticas e Nucleares, Cidade Univ., Sao Paulo, SP (Brazil)

    2001-07-01

    Low-pressure powder injection moulding was used to obtain AISI 316L stainless steel parts. A rheological study was undertaken using gas-atomised powders and binders. The binders used were based on carnauba wax, paraffin, low density polyethylene and microcrystalline wax. The metal powders were characterised in terms of morphology, particle size distribution and specific surface area. These results were correlated to the rheological behaviour. The mixture was injected in the shape of square bar specimens to evaluate the performance of the injection process in the green state, and after sintering. The parameters such as injection pressure, viscosity and temperature were analysed for process optimisation. The binders were thermally removed in low vacuum with the assistance of alumina powders. Debinding and sintering were performed in a single step. This procedure shortened considerably the debinding and sintering time. (orig.)

  12. Assessment methods of injection moulded nano-patterned surfaces

    DEFF Research Database (Denmark)

    Menotti, S.; Bisacco, G.; Hansen, H. N.

    2014-01-01

    algorithm for feature recognition. To compare the methods, the mould insert and a number of replicated nano-patterned surfaces, injection moulded with an induction heating aid, were measured on nominally identical locations by means of an atomic force microscope mounted on a manual CMM....

  13. Transcription of Small Surface Structures in Injection Moulding - An Experimental Study

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Kjær, Erik Michael

    2000-01-01

    The ability to replicate the surface roughness from mold wall to the plastic part in injection moldning has many functional and cosmetic important implications from medical use to designer products. Generally the understanding of surface transcription i.e the the replication of the surface...... structure from the mould to plastic part, also relates to micro injection moulding and moulding of parts with specific micro structures on the surface such as optical parts. The present study concerns transcription of surface roughness as a function of process parameters. The study is carried out...

  14. Bond strength of two component injection moulded MID

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2006-01-01

    Most products of the future will require industrially adapted, cost effective production processes and on this issue two-component (2K) injection moulding is a potential candidate for MID manufacturing. MID based on 2k injection moulded plastic part with selectively metallised circuit tracks allows...... the two different plastic materials in the MID structure require good bonding between them. This paper finds suitable combinations of materials for MIDs from both bond strength and metallisation view-point. Plastic parts were made by two-shot injection moulding and the effects of some important process...... the integration of electrical and mechanical functionalities in a real 3D structure. If 2k injection moulding is applied with two polymers, of which one is plateable and the other is not, it will be possible to make 3D electrical structures directly on the component. To be applicable in the real engineering field...

  15. Yield stress distribution in injection-moulded glassy polymers

    NARCIS (Netherlands)

    Verbeeten, W.M.H.; Kanters, M.J.W.; Engels, T.A.P.; Govaert, L.E.

    2015-01-01

    A methodology for structural analysis simulations is presented that incorporates the distribution of mechanical propertiesalong the geometrical dimensions of injection-moulded amorphous polymer products. It is based on a previously developedmodelling approach, where the thermomechanical history

  16. Replication quality assessment and uncertainty evaluation of a polymer precision injection moulded component

    DEFF Research Database (Denmark)

    Baruffi, Federico; Calaon, Matteo; Tosello, Guido

    2017-01-01

    Precision injection moulding holds a central role in manufacturing as only replication process currently capable of accurately producing complex shaped polymer parts integrating micrometric features on a mass scale production. In this scenario, a study on the replication quality of a polymer...... injection moulded precision component for telecommunication applications is presented. The effects of the process parameters on the component dimensional variation have been investigated using a statistical approach. Replication fidelity of produced parts has been assessed using a focus variation microscope...... with sub-micrometric resolution. Measurement uncertainty has then been evaluated, according to the GUM considering contributions from different process settings combinations and mould geometries. The analysis showed that the injection moulding manufacturing process and the utilized measurement chain...

  17. Development and characterisation of injection moulded, all-polypropylene composites

    Directory of Open Access Journals (Sweden)

    A. Kmetty

    2013-02-01

    Full Text Available In this work, all-polypropylene composites (all-PP composites were manufactured by injection moulding. Prior to injection moulding, pre-impregnated pellets were prepared by a three-step process (filament winding, compression moulding and pelletizing. A highly oriented polypropylene multifilament was used as the reinforcement material, and a random polypropylene copolymer (with ethylene was used as the matrix material. Plaque specimens were injection moulded from the pellets with either a film gate or a fan gate. The compression moulded sheets and injection moulding plaques were characterised by shrinkage tests, static tensile tests, dynamic mechanical analysis and falling weight impact tests; the fibre distribution and fibre/matrix adhesion were analysed with light microscopy and scanning electron microscopy. The results showed that with increasing fibre content, both the yield stress and the perforation energy significantly increased. Of the two types of gates used, the fan gate caused the mechanical properties of the plaque specimens to become more homogeneous (i.e., the differences in behaviour parallel and perpendicular to the flow direction became negligible.

  18. Development of injection moulded, ultrasonically welded immiscible phase filtration devices

    DEFF Research Database (Denmark)

    Kistrup, Kasper

    for ultrasonic welding, suitable for microfluidic systems. A methodology has been established where energy directors can be quickly added to existing mould inserts, using laser micromachining. The produced device was performance tested by isolating methicillin-resistant Staphylococcus aureus from bovine whole....... The device appliesmagnetic bead-based solid-phase extraction for nucleic acid extraction from biological samples, using the immiscible phase filtration (IPF) approach. Device development has employed injection moulding for part fabrication and ultrasonic welding for bonding. Rapid prototyping...

  19. Replication of micro structured surface by injection moulding of PEEK

    DEFF Research Database (Denmark)

    Zhang, Yang; Hansen, Hans Nørgaard; Sørensen, Søren

    A micro-structured Ni insert was investigated for PEEK injection moulding. The micro features are circular holes 4 μm in diameter and 2 μm deep, with a 2 μm edge-to-edge distance. 6000 moulding cycles was operated. Half of the insert was coated by 200nm CrN. PEEK parts produced by the coated side...

  20. Influence of the recycled material percentage on the rheological behaviour of HDPE for injection moulding process.

    Science.gov (United States)

    Javierre, C; Clavería, I; Ponz, L; Aísa, J; Fernández, A

    2007-01-01

    The amount of polymer material wasted during thermoplastic injection moulding is very high. It comes from both the feed system of the part, and parts necessary to set up the mould, as well as the scrap generated along the process due to quality problems. The residues are managed through polymer recycling that allows reuse of the materials in the manufacturing injection process. Recycling mills convert the parts into small pieces that are used as feed material for injection, by mixing the recycled feedstock in different percentages with raw material. This mixture of both raw and recycled material modifies material properties according to the percentage of recycled material introduced. Some of the properties affected by this modification are those related to rheologic behaviour, which strongly conditions the future injection moulding process. This paper analyzes the rheologic behaviour of material with different percentages of recycled material by means of a capillary rheometer, and evaluates the influence of the corresponding viscosity curves obtained on the injection moulding process, where small variations of parameters related to rheological behaviour, such as pressure or clamping force, can be critical to the viability and cost of the parts manufactured by injection moulding.

  1. Free-form nanostructured tools for plastic injection moulding

    DEFF Research Database (Denmark)

    Kafka, Jan; Sonne, Mads Rostgaard; Lam, Yee Cheong

    realized and successfully transferred to plastic parts during injection moulding.As an example, we present theory and results regarding the imprint of pillar nanostructures on a semi-spherical mold surface, followed by injection molding of the same. The deformation of the flexible stamp is characterized...... by measurement of inter-pillar distance on various points on the sphere, and compared to predictions provided by a geometrical model. Moulded plastic parts show good replication of the pillar structure.There are various practical advantages to the new process: the application of the coating is possible on both...

  2. Characterization and analysis of weld lines on micro-injection moulded parts using atomic force microscopy (AFM)

    DEFF Research Database (Denmark)

    Tosello, Guido; Gava, Alberto; Hansen, Hans Nørgaard

    2009-01-01

    In recent years plastic moulding techniques, such as injection moulding, have been developed to fulfil the needs of micro-components fabrication. Micro-injection moulding (SLIM) is the process which enables the mass production of polymer micro-systems such as micro-mechanical parts, micro...... the two original flows will generate and a weld line is formed on the surface of the micro-moulded part. This phenomenon has to be avoided or at least reduced, since in the weld line area the mechanical properties are poorer than in the bulk part, creating strength problems on the final part. Although...... injection moulding parameters on the weld lines' dimensions is presented, using an atomic force microscope (AFM). Depth and width of weld lines were chosen as parameters to be optimized....

  3. C-stop production by micro injection moulding

    DEFF Research Database (Denmark)

    Islam, Aminul

    of engineering micro product which integrate many features like beam snapfit, annular snapfit, hinge connection, filter grid, house, lid etc in a single product. All the features are in micro dimensional scale and manufactured by single step of injection moulding. This presentation will cover industrial...

  4. The computation of properties of injection-moulded products

    NARCIS (Netherlands)

    Douven, L.F.A.; Baaijens, F.P.T.; Meijer, H.E.H.

    1995-01-01

    Injection moulding is a flexible production technique for the manufacture of complex shaped, thin walled polymer products that require minimal finishing. During processing, the polymer experiences a complex deformation and temperature history that affects the final properties of the product. In a

  5. Injection Moulding of Plastic Parts with Surface Microstructures

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Kjær, Erik Michael

    2003-01-01

    structures with heights of 9 µm and aspect ratios from 0.2 to 1. For topographical characterisation a confocal laser scanning microscope was used. The injection moulding process conditions were varied over the recommended process window for the material, and the process was analysed using commercial...

  6. Quality of topographical micro replication in injection moulding

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Hansen, Hans Nørgaard; Bariani, Paolo

    2003-01-01

    The quality of tool-to-part rough surface topography replication in injection moulding has been investigated. Quantitative descriptors suitable for detecting process conditions induced topography changes have been identified using a statistical criterion. The experimental work is based on a tool ...

  7. Binder Development for Metal Injection Moulding: A CSIR Perspective

    CSIR Research Space (South Africa)

    Machaka, R

    2014-05-01

    Full Text Available The paper reviews the CSIR’s progress and challenges concerning the development of a wax-based binder system suitable for metal injection moulding (MIM). It reports on a consolidation study wherein different widely used wax-based feedstock...

  8. Characterization and analysis of sub-micron surface roughness of injection moulded microfluidic systems using White Light Interferometry

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2009-01-01

    Surface topography is of great importance in polymer micro fluidics, therefore the replication capability of the process and the surface quality of the tool has to be suitably optimized. In this paper, optical profilometry (white light interferometry, WLI) is implemented for topographical...... characterization of polymer surfaces. In particular the study considers replication performance of injection moulding applied for the realization of microfluidic systems for blood analysis. Parts were produced by means of a series of statistically designed injection moulding experiments. Three process parameters...

  9. Gas-assisted injection moulding: adding two components and moveable inserts

    NARCIS (Netherlands)

    Neerincx, P.E.; Meijer, H.E.H.

    2009-01-01

    Gas assisted injection moulding (GAIM) is a technique that is successfully used for compensating shrinkage during injection moulding of thick walled but still accurate products with low levels of internal stresses and frozen-in orientation. In this study the authors apply GAIM in moulding 28 mm

  10. Inner centering in parting line area of injection mould using side locks

    DEFF Research Database (Denmark)

    Mahshid, Rasoul; Hansen, Hans Nørgaard

    2017-01-01

    Injection moulding is characterized by high precision requirements. In particular, the demands regarding the mould plates alignment are in order of few micro meters. This research introduces a methodology to measure the misalignment in injection moulding. Eddy current sensors are used in the system...

  11. A new approach for the validation of filling simulations in micro injection moulding

    DEFF Research Database (Denmark)

    Gava, Alberto; Tosello, Guido; Lucchetta, Giovanni

    2007-01-01

    In manufacturing polymer micro products, numerical simulations are used with the same purposes as in conventional injection moulding, mainly the optimization of micro components design, the optimization of process parameters and the decrease of production costs. Dedicated simulations softwares fail...... to be improved. The main objective of this work is to evaluate whether the present numerical codes are suitable to characterize melt flow patterns in a micro cavity. In order to test the accuracy of the software, real and simulated experiments were performed and used to investigate the filling of a micro moulded...

  12. Assessment of sub-mm features replication capability in injection moulding using a multi-cavity tool produced by additive manufacturing

    DEFF Research Database (Denmark)

    Davoudinejad, A.; Charalambis, A.; Zhang, Y.

    This research investigates the effect of injection moulding process parameters on photopolymer mould inserts produced with the Digital Light Processing (DLP) additive manufacturing (AM) method. The main motivation of applying AM to produce mould inserts, is the potential of reducing lead time...... and manufacturing cost, as well as achieving a more flexible manufacturing method in case of non-mass produced products such as prototypes. In this research moulds inserts of 20 x 20 x 2.7 mm with mould cavities as small as 5 x 4 mm in dimensions are tested. The parts are analyzed and evaluated by the measurements...

  13. Two component injection moulding: an interface quality and bond strength dilemma

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2008-01-01

    on quality parameters of the two component parts. Most engineering applications of two component injection moulding calls for high bond strength between the two polymers, on the other hand a sharp and well-defined interface between the two polymers are required for applications like selective metallization...... of polymers, parts for micro applications and also for the aesthetic purpose of the final product. The investigation presented in this paper indicates a dilemma between obtaining reasonably good bond strength and at the same time keeping the interface quality suitable for applications. The required process...... conditions for a sharp and well-defined interface are exactly the opposite of what is congenial for higher bond strength. So in the production of two component injection moulded parts, there is a compromise to make between the interface quality and the bond strength of the two polymers. Also the injection...

  14. PROTVINO: Mass-production of scintillator tiles by injection moulding

    International Nuclear Information System (INIS)

    Anon.

    1994-01-01

    The technique of the segmented sandwich-calorimeters with wavelength-shifting readout, especially its large-scale application in big detectors, requires enormous quantities of a cheap scintillator tiles of moderate dimensions (20 x 20 cm 2 ). Initial trials carried out in the Institute for High Energy Physics (IHEP), Protvino, Russia almost ten years ago showed that manufacturing such scintillator tiles was possible using an ordinary commercially-available granulated optical polystyrene, an existing technology of plastic dyeing, and a well-known process of the injection moulding, used to produce plastic goods (like buttons!)

  15. Decreasing the Functioning Consumptions of Plastics Injection Moulding Machines

    Science.gov (United States)

    Vasilache, V.; Vasilache, M.; Vasilache, A.

    2017-06-01

    A share of about 75% in the cost of a plastic moulded part is held by the energy consumption of the injection machine. It is the heating system of the plasticising unit which is responsible for the energophague character of the process. The transfer rate from the heating elements to the plasticising cylinder depends hardly on the geometry of the system. A new heating system is designed, replacing the classical systems which are applied on the exterior of the cylinder with an “engrooved system”. Proposed heating system leads to decreasing of energy consumption up to 30 % and maintenance costs up to 10 %. A supplementary possibility to decrease the maintenance costs is to modify the geometry of the injection torpedo. The proposed geometry eliminates the possibility of any breaking or gripping related to the injection torpedo.

  16. Micro injection moulding process validation for high precision manufacture of thermoplastic elastomer micro suspension rings

    DEFF Research Database (Denmark)

    Calaon, M.; Tosello, G.; Elsborg Hansen, R.

    Micro injection moulding (μIM) is one of the most suitable micro manufacturing processes for flexible mass-production of multi-material functional micro components. The technology was employed in this research used to produce thermoplastic elastomer (TPE) micro suspension rings identified...... main μIM process parameters (melt temperature, injection speed, packing pressure) using the Design of Experiment statistical technique. Measurements results demonstrated the importance of calibrating mould´s master geometries to ensure correct part production and effective quality conformance...... on the frequency in order to improve the signal quality and assure acoustic reproduction fidelity. Production quality of the TPE rings drastically influence the product functionality. In the present study, a procedure for μIM TPE micro rings production optimization has been established. The procedure entail using...

  17. Weld line optimization on thermoplastic elastomer micro injection moulded components using 3D focus variation optical microscopy

    DEFF Research Database (Denmark)

    Hasnaes, F.B.; Elsborg, R.; Tosello, G.

    2015-01-01

    The presented study investigates weld line depth development across a micro suspension ring. A focus variation microscope was used to obtain 3D images of the weld line area. Suspension rings produced with different micro injection moulding process parameters were examined to identify the correlat......The presented study investigates weld line depth development across a micro suspension ring. A focus variation microscope was used to obtain 3D images of the weld line area. Suspension rings produced with different micro injection moulding process parameters were examined to identify...

  18. Selected parameters of moulding sands for designing quality control systems

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2010-07-01

    Full Text Available One of the modern methods of production optimisation are artificial neural networks. Neural networks owe their popularity to the fact thatthey are convenient tools, which can be utilised in a wide scope of problems. They are capable of reflecting complex functions. Especiallytheir non-linearity should be emphasised. They are gaining wider and wider application in the foundry industry, among others, to controlmelting processes in cupolas and arc furnaces, designing castings and supply systems, control of moulding sands treatments, prediction ofproperties of cast alloys as well as selecting die casting.An attempt of the application neural networks to the quality control of moulding sands with bentonite is presented in the paper. This isa method of assessing the suitability of moulding sands by finding correlations in between individual parameters, by means of artificialneural network systems. The presented investigations were performed with the application of the Statistica 8.0 program.The investigations were aimed at the selection of the proper kind of a neural network for prediction a sand moistness on the bases ofcertain moulding sand properties such as: permeability, compactibility and friability. These parameters – determined as sand moistness functions - were introduced as initial parameters.Application of the Statistica program allowed for an automatic selection of the most suitable network for the reflection of dependencies and interactions existing among the proposed parameters. The best results were obtained for unidirectional multi-layer perception network (MLP. The neural network sensitivity to individual moulding sand parameters was determined, which allowed to reject not important parameters when constructing the network.

  19. Additive manufacturing for the production of inserts for micro injection moulding

    DEFF Research Database (Denmark)

    Mischkot, Michael; Hansen, Hans Nørgaard; Pedersen, David Bue

    2015-01-01

    The production of inserts for micro injection moulding using additive manufacturing technology has the potential to greatly improve the efficiency of pilot production and reduce overall time to market. In this work, Digital Light Processing (DLP) was used to produce micro injection moulding inserts...

  20. On the performance of micro injection moulding process simulations of TPE micro rings

    DEFF Research Database (Denmark)

    Baruffi, Federico; Calaon, Matteo; Tosello, Guido

    , a case study based on the micro injection moulding process of thermoplastic elastomer (TPE) micro rings (volume: 1.5 mm3, mass: 2.2 mg) for sensors application is treated. Injection moulding process simulations using Autodesk Moldflow Insight 2016® were applied with the aim of accomplishing two main...

  1. Improved Processing of Titanium Alloys by Metal Injection Moulding

    International Nuclear Information System (INIS)

    Sidambe, A T; Figueroa, I A; Todd, I; Hamilton, H

    2011-01-01

    The commercially pure (CP-Ti) and Ti6Al4V (Ti-64) powders with powder size of sub 45-micron were mixed with a water soluble binder consisting of a major fraction of Polyethylene Glycol (PEG), a minor fraction of Polymethylmethacrylate (PMMA) and some stearic acid as surfactant. The pelletised mix was injection-moulded into standard tensile bar specimens and then subjected solvent debinding by water leaching and thermal debinding in an argon atmosphere. The titanium compacts were then subjected to sintering studies using the Taguchi method. The results of the oxygen impurity levels of the sintered parts are presented in this paper. Titanium parts conforming to Grade 2 requirements were achieved for CP-Ti whilst those conforming to Grade 5 were achieved for Ti-64.

  2. GTE blade injection moulding modeling and verification of models during process approbation

    Science.gov (United States)

    Stepanenko, I. S.; Khaimovich, A. I.

    2017-02-01

    The simulation model for filling the mould was developed using Moldex3D, and it was experimentally verified in order to perform further optimization calculations of the moulding process conditions. The method described in the article allows adjusting the finite-element model by minimizing the airfoil profile difference between the design and experimental melt motion front due to the differentiated change of power supplied to heating elements, which heat the injection mould in simulation. As a result of calibrating the injection mould for the gas-turbine engine blade, the mean difference between the design melt motion profile and the experimental airfoil profile of no more than 4% was achieved.

  3. Effects of moulding and environmental conditions on the mechanical and surface properties of injection moulded santoprene rubber

    DEFF Research Database (Denmark)

    Islam, Aminul; Ruby, Tobias M.; Jessen, Rikke L.

    the electronics inside from environmental hazards. The sealing ring is injection moulded in Santoprene-a thermoplastic vulcanizate consisting of Polypropelene and highly vulcanized EPDM rubber. The scope of the project was therefore to investigate the properties of Santoprene and make an immediate evaluation...

  4. Replication of Micro pillars by PEEK injection moulding with CrN coated Ni tool

    DEFF Research Database (Denmark)

    Zhang, Yang; Hansen, Hans Nørgaard; Sørensen, Søren

    2015-01-01

    A micro-structured nickel insert was investigatedfor polyether ether ketone (PEEK) injection moulding. Themicro-features were circular holes 4 μm in diameter and2 μm deep, with a 2-μm edge-to-edge distance. Six thousand moulding cycles were operated. Half of the insert was coatedby approximately...

  5. High Accuracy Three-dimensional Simulation of Micro Injection Moulded Parts

    DEFF Research Database (Denmark)

    Tosello, Guido; Costa, F. S.; Hansen, Hans Nørgaard

    2011-01-01

    Micro injection moulding (μIM) is the key replication technology for high precision manufacturing of polymer micro products. Data analysis and simulations on micro-moulding experiments have been conducted during the present validation study. Detailed information about the μIM process was gathered...

  6. Replication of microstructures on three-dimensional geometries by injection moulding of liquid silicone rubber

    DEFF Research Database (Denmark)

    Zhang, Yang; Mischkot, Michael; Hansen, Hans Nørgaard

    2015-01-01

    In this paper, liquid silicon rubber (LSR) parts with micro pillars are studied. The LSR parts were produced by injection moulding and are used as anchoring device for electrode implants inside humans. Micro-structures with specific dimension on implant surfaces can reduce encapsulation...... by the human body, thereby improving implant performance. This paper presents a method of applying micro structure on 3D parts. A Ni-plate with micro holes on the surface was cut into inserts and stuck in a cavity for injection moulding. 1000 injection moulding cycles were performed. Key dimensions...

  7. High Power Picosecond Laser Surface Micro-texturing of H13 Tool Steel and Pattern Replication onto ABS Plastics via Injection Moulding

    Science.gov (United States)

    Otanocha, Omonigho B.; Li, Lin; Zhong, Shan; Liu, Zhu

    2016-03-01

    H13 tool steels are often used as dies and moulds for injection moulding of plastic components. Certain injection moulded components require micro-patterns on their surfaces in order to modify the physical properties of the components or for better mould release to reduce mould contamination. With these applications it is necessary to study micro-patterning to moulds and to ensure effective pattern transfer and replication onto the plastic component during moulding. In this paper, we report an investigation into high average powered (100 W) picosecond laser interactions with H13 tool steel during surface micro-patterning (texturing) and the subsequent pattern replication on ABS plastic material through injection moulding. Design of experiments and statistical modelling were used to understand the influences of laser pulse repetition rate, laser fluence, scanning velocity, and number of scans on the depth of cut, kerf width and heat affected zones (HAZ) size. The characteristics of the surface patterns are analysed. The process parameter interactions and significance of process parameters on the processing quality and efficiency are characterised. An optimum operating window is recommended. The transferred geometry is compared with the patterns generated on the dies. A discussion is made to explain the characteristics of laser texturing and pattern replication on plastics.

  8. High accuracy and precision micro injection moulding of thermoplastic elastomers micro ring production

    DEFF Research Database (Denmark)

    Calaon, Matteo; Tosello, Guido; Elsborg, René

    2016-01-01

    The mass-replication nature of the process calls for fast monitoring of process parameters and product geometrical characteristics. In this direction, the present study addresses the possibility to develop a micro manufacturing platform for micro assembly injection moulding with real-time process....../product monitoring and metrology. The study represent a new concept yet to be developed with great potential for high precision mass-manufacturing of highly functional 3D multi-material (i.e. including metal/soft polymer) micro components. The activities related to HINMICO project objectives proves the importance...

  9. Polyolefin backbone substitution in binders for low temperature powder injection moulding feedstocks.

    Science.gov (United States)

    Hausnerova, Berenika; Kuritka, Ivo; Bleyan, Davit

    2014-02-27

    This paper reports the substitution of polyolefin backbone binder components with low melting temperature carnauba wax for powder injection moulding applications. The effect of various binder compositions of Al₂O₃ feedstock on thermal degradation parameters is investigated by thermogravimetric analysis. Within the experimental framework 29 original feedstock compositions were prepared and the superiority of carnauba wax over the polyethylene binder backbone was demonstrated in compositions containing polyethylene glycol as the initial opening agent and governing the proper mechanism of the degradation process. Moreover, the replacement of synthetic polymer by the natural wax contributes to an increase of environmental sustainability of modern industrial technologies.

  10. Polyolefin Backbone Substitution in Binders for Low Temperature Powder Injection Moulding Feedstocks

    Directory of Open Access Journals (Sweden)

    Berenika Hausnerova

    2014-02-01

    Full Text Available This paper reports the substitution of polyolefin backbone binder components with low melting temperature carnauba wax for powder injection moulding applications. The effect of various binder compositions of Al2O3 feedstock on thermal degradation parameters is investigated by thermogravimetric analysis. Within the experimental framework 29 original feedstock compositions were prepared and the superiority of carnauba wax over the polyethylene binder backbone was demonstrated in compositions containing polyethylene glycol as the initial opening agent and governing the proper mechanism of the degradation process. Moreover, the replacement of synthetic polymer by the natural wax contributes to an increase of environmental sustainability of modern industrial technologies.

  11. Two-component micro injection moulding for hearing aid applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Marhöfer, David Maximilian

    2012-01-01

    . The moulding machine was a state-of-the-art 2k micro machine from DESMA. The fabricated micro part was a socket house integrated with a sealing ring for the receiver-in-canal hearing instrument. The test performed on the demonstrator showed the potential of the 2k moulding technology to be able to solve some...

  12. Surface wear of TiN coated nickel tool during the injection moulding of polymer micro Fresnel lenses

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Gasparin, Stefania

    2012-01-01

    Limited tool life of nickel mould inserts represents an issue for the mass-production of polymer optics with complex micro three-dimensional geometries by injection moulding. TiN coating was applied to a nickel insert for the injection moulding of polycarbonate micro Fresnel lenses. Surface wear...

  13. Evaluation of optical functional surfaces on the injection moulding insert by micro milling process

    DEFF Research Database (Denmark)

    Li, Dongya; Davoudinejad, Ali; Zhang, Yang

    2017-01-01

    This study presents the optimization of micro milling process for manufacturing injection moulding inserts with an optical functionalsurface. The objective is the optimal surface functionality. Micro ridges were used as the microstructures to realize the function to generate contrast between...

  14. Examining the influence of injection speed and mould temperature on the tensile strength of polypropylene and ABS

    DEFF Research Database (Denmark)

    Aarøe, Esben Raahede; Blaimschein, Karl Stephan; Deker, Lasse

    This report is the final task of course “41738 Experimental Plastics Technology” in the three weeks period of June 2009 at DTU, IPL. The aim of this project has been to investigate the ultimate tensile strength behaviour of two different polymers, with different structural composition, by varying...... the injection speed and the mold temperature independently while keeping all other process parameters fixed. In addition the scaling from production of large to small geometries has been investigated by doing two parallel productions and test setups of respectively injection moulded and micro injection moulded...... specimens. After production and tensile testing the specimens were examined with a microscope to underpin conclusions from the tensile test data. It was experienced that the injection speed in general increased the the tensile strength by orienting the polymeric-chains lengthwise in the specimens and thus...

  15. Experimental investigation of the factors influencing the polymer-polymer bond strength during two component injection moulding

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2007-01-01

    Two component injection moulding is a commercially important manufacturing process and a key technology for Moulded Interconnect Devices (MIDs). Many fascinating applications of two component or multi component polymer parts are restricted due to the weak interfacial adhesion of the polymers...... effectively control the adhesion between two polymers. The effects of environmental conditions on the bond strength after moulding are also investigated. The material selections and environmental conditions were chosen based on the suitability of MID production, but the results and discussion presented....... A thorough understanding of the factors that influence the bond strength of polymers is necessary for multi component polymer processing. This paper investigates the effects of the process and material parameters on the bond strength of two component polymer parts and identifies the factors which can...

  16. Yttria coating on quartz mould inner surface for fabrication of metal fuel slug using injection casting process

    International Nuclear Information System (INIS)

    Vinod, A.V.; Hemanth Kumar, S.; Manivannan, A.; Muralidaran, P.; Anthonysamy, S.; Sudha, R.

    2016-01-01

    Quartz moulds are used for casting metal alloy of U-Zr slugs by injection casting process. Ceramic (Y_2O_3) coating on inner surface of the quartz mould is provided to avoid silica contamination in the fuel slugs during casting. Experiments were carried out to standardise the coating process and optimising various parameters such as particle size of Y_2O_3, choice of suitable binder, method for application of coating, drying and sintering at high temperature to ensure uniformity and strength of coating. Required Coating thickness of ∼40 μm was achieved on a quartz mould of inner diameter of 4.98±0.01mm. Experimental procedure for coating on inner surface of the quartz tubes using yttrium oxide is described in this work. (author)

  17. Effect of processing conditions on shrinkage in injection moulding

    NARCIS (Netherlands)

    Jansen, K.M.B.; van Dijk, D.J.; Husselman, M.H.

    1998-01-01

    A systematic study on the effect of processing conditions on mold shrinkage was undertaken for seven common thermoplastic polymers. It turned out that the holding pressure was always the key parameter. The effect of the melt temperature is slightly less important. Injection velocity and mold

  18. Injection Moulding Simulation and Experimental Validation of Hearing Aid Shells

    DEFF Research Database (Denmark)

    Islam, Aminul; Li, Xiaoliu

    and warpage were taken as the main comparison criteria. Different parameter settings in Moldex3D were investigated to find their influence on the accuracy of the simulation. Results showed that the injection molding process prediction from the simulation was relatively precise when the nozzle geometry...

  19. Rheological and thermal analysis of the filling stage of injection moulding

    Directory of Open Access Journals (Sweden)

    A. Szucs

    2012-08-01

    Full Text Available Flow conditions are different in the cavity of the injection mould from the capillary flow of a laboratory rheological instrument. An injection moulding slit die rheometer (Rheo-mould was designed with a series of slit and orifice dies. Four pressure sensors were built in the stationary side of the mould, therefore the pressure could be measured at four different places. A changeable slit die insert was designed in the moving side. The shear stress and the shear rate can be calculated from the pressure gradient and from the flow rate of the melt, respectively. Flow curves of low density polyethylene were determined using Bagley, Rabinowitsch and Mooney corrections. The results were compared to the flow curves determined by Göttfert and Haake capillary equipments. It was found that the agreement between the methods is excellent.

  20. Micro-MID Manufacturing By Two-Shot Injection Moulding

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2008-01-01

    a specific MID process chain is used for micro products, many technical challenges are encountered which would not be problems for macro scale products. This paper investigates on a specific MID process chain (two shot moulding) and discusses the technical difficulties associated with the production process...

  1. Closed-Loop Tension Control System for Injection Moulding Machine

    African Journals Online (AJOL)

    When the mould unit is full, this drive keeps transporting filament materials without proper control. This project developed a closed loop feedback tension control system and it is to replace servo motor drive system for the transportation of filament and it demonstrated a new technological advancement and the theory of ...

  2. Air Flow and Gassing Potential in Micro-injection Moulding

    DEFF Research Database (Denmark)

    Griffithsa, C.A.; Dimova, S.S.; Scholz, S.

    2011-01-01

    valuable information about the process dynamics and also about the filling of a cavity by a polymer melt. In this paper, a novel experimental set-up is proposed to monitor maximum air flow and air flow work as an integral of the air flow over time by employing a MEMS gas sensor mounted inside the mould...

  3. Evaluation of Injection Molding Process Parameters for Manufacturing Polyethylene Terephthalate

    Directory of Open Access Journals (Sweden)

    Marwah O.M.F.

    2017-01-01

    Full Text Available Quality control is an important aspect in manufacturing process. The quality of product in injection moulding is influenced by injection moulding process parameter. In this study, the effect of injection moulding parameter on defects quantity of PET preform was investigated. Optimizing the parameter of injection moulding process is critical to enhance productivity where parameters must operate at an optimum level for an acceptable performance. Design of Experiment (DOE by factorial design approach was used to find an optimum parameter setting and reduce the defects. In this case study, Minitab 17 software was used to analyses the data. The selected input parameters were mould hot runner temperature, water cooling chiller temperature 1 and water cooling chiller temperature 2. Meanwhile, the output for the process was defects quantity of the preform. The relationship between input and output of the process was analyzed using regression method and Analysis of Variance (ANOVA. In order to interpolate the experiment data, mathematical modeling was used which consists of different types of regression equation. Next, from the model, 95% confidence level (p-value was considered and the significant parameter was figured out. This study involved a collaboration with a preform injection moulding company which was Nilai Legasi Plastik Sdn Bhd. The collaboration enabled the researchers to collect the data and also help the company to improve the quality of its production. The results of the study showed that the optimum parameter setting that could reduce the defect quantity of preform was MHR= 88°C, CT1= 24°C and CT2= 27°C. The comparison defect quantity analysis between current companies setting with the optimum setting showed improvement by 21% reduction of defect quantity at the optimum setting. Finally, from the optimization plot, the validation error between the prediction value and experiment was 1.72%. The result proved that quality of products

  4. Micro injection moulding process optimization of an ultra-small POM three-dimensional component

    DEFF Research Database (Denmark)

    Baruffi, Federico; Calaon, Matteo; Tosello, Guido

    Replication-based manufacturing processes are a cost effective method for producing complex and net-shaped components [1]. Micro injection moulding has a prominent place among them for its capability of accurately and precisely produce micro plastic parts in large production scale [2], [3......]. In this study, the optimization of the micro injection moulding process of an ultra-small (volume: 0.07 mm3; mass: 0.1 mg) three-dimensional Polyoxymethylene (POM) micro component for medical applications (see Figure 1) is presented. Preliminary experiments highlighted the need for venting channels in order...... with respect to design specifications, the flash areal size was utilized as quality indicator. A design of the experiments approach was carried out in order to study the effects of melt temperature, mould temperature, holding pressure and injection speed. For this task, a two-level full factorial design...

  5. Influence of tribological additives on friction and impact performance of injection moulded polyacetal

    DEFF Research Database (Denmark)

    Laursen, Jens Lolle; Sivebæk, Ion Marius; Christoffersen, L.W.

    2009-01-01

    Tribological additives are used to improve frictional properties of injection moulded thermoplastics. The additives might however also affect the mechanical properties of the material. The influence of processing conditions on both frictional and mechanical properties is highly relevant in the de......Tribological additives are used to improve frictional properties of injection moulded thermoplastics. The additives might however also affect the mechanical properties of the material. The influence of processing conditions on both frictional and mechanical properties is highly relevant...... in the development of tribologically modified grades. In the present study we investigate how two commonly used tribological additives, polydimethylsiloxane and polytetrafluoroethylene, affect friction and impact properties of polyacetal (polyoxymethylene). A new injection mould provides test specimens for both...

  6. Quality control and process capability assessment for injection-moulded micro mechanical parts

    DEFF Research Database (Denmark)

    Gasparin, Stefania; Tosello, Guido; Hansen, Hans Nørgaard

    2013-01-01

    Quality control of micro components is an increasing challenge. Smaller mechanical parts are characterized by smaller tolerance to be verified. This paper focuses on the dimensional verification of micro injection-moulded components selected from an industrial application. These parts are measured...... using an optical coordinate measuring machine, which guarantees fast surface scans suitable for inline quality control. The uncertainty assessment of the measurements is calculated and three analyses are carried out and discussed in order to investigate the influence parameters in optical coordinate...... metrology. The estimation of the total variability of the optical measurements and the instrument repeatability are reported; moreover, the measurement system capability is evaluated according to the measurement system capability indices Cg and Cgk....

  7. An image-based method for objectively assessing injection moulded plastic quality

    DEFF Research Database (Denmark)

    Hannemose, Morten; Nielsen, Jannik Boll; Zsíros, László

    2017-01-01

    In high volume productions based on casting processes, like high-pressure die casting (HPDC) or injection moulding, there is a wide range of variables that affect the end quality of produced parts. These variables include production parameters (temperature, pressure, mixture), and external factors...... (humidity, temperature, etc.). With this many variables it is a challenge to maintain a stable output quality, wherefore massive amounts of resources are spent on quality assurance (QA) of produced parts. Currently, this QA is done manually through visual inspection. We demonstrate how a multispectral...... imaging system can be used to automatically rate the quality of a produced part using an autocorrelation and a Fourier-based method. These methods are compared with human rankings and achieve good correlations on a variety of samples....

  8. Micro-Injection Moulding In-Line Quality Assurance Based on Product and Process Fingerprints

    DEFF Research Database (Denmark)

    Baruffi, Federico; Calaon, Matteo; Tosello, Guido

    2018-01-01

    significant dimensional features of the micro part were measured using a focus variation microscope. Their dependency on the variation of µIM process parameters was studied with a Design of Experiments (DoE) statistical approach. A correlation study allowed the identification of the product fingerprint, i...... of the study showed that the dimensional quality of the micro component could be effectively controlled in-line by combining the two fingerprints, thus opening the door for future µIM in-line process optimization and quality assessment.......Micro-injection moulding (μIM) is a replication-based process enabling the cost-effective production of complex and net-shaped miniaturized plastic components. The micro-scaled size of such parts poses great challenges in assessing their dimensional quality and often leads to time...

  9. The Optimisation of Processing Condition for Injected Mould Polypropylene-Nanoclay-Gigantochloa Scortechinii based on Melt Flow Index

    Science.gov (United States)

    Othman, M. H.; Rosli, M. S.; Hasan, S.; Amin, A. M.; Hashim, M. Y.; Marwah, O. M. F.; Amin, S. Y. M.

    2018-03-01

    The fundamental knowledge of flow behaviour is essential in producing various plastic parts injection moulding process. Moreover, the adaptation of advanced polymer-nanocomposites such as polypropylene-nanoclay with natural fibres, for instance Gigantochloa Scortechinii may boost up the mechanical properties of the parts. Therefore, this project was proposed with the objective to optimise the processing condition of injected mould polypropylene-nanoclay-Gigantochloa Scortechini fibres based on the flow behaviour, which was melt flow index. At first, Gigantochloa Scortechinii fibres have to be preheated at temperature 120°C and then mixed with polypropylene, maleic anhydride modified polypropylene oligomers (PPgMA) and nanoclay by using Brabender Plastograph machine. Next, forms of pellets were produced from the samples by using Granulator machine for use in the injection moulding process. The design of experiments that was used in the injection moulding process was Taguchi Method Orthogonal Array -L934. Melt Flow Index (MF) was selected as the response. Based on the results, the value of MFI increased when the fiber content increase from 0% to 3%, which was 17.78 g/10min to 22.07 g/10min and decreased from 3% to 6%, which was 22.07 g/10min to 20.05 g/10min and 3%, which gives the highest value of MFI. Based on the signal to ratio analysis, the most influential parameter that affects the value of MFI was the melt temperature. The optimum parameter for 3% were 170°C melt temperature, 35% packing pressure, 30% screw speed and 3 second filling time.

  10. THE WEAR OF INJECTION MOULD FUNCTIONAL PARTS IN CONTACT WITH POLYMER COMPOSITES

    Directory of Open Access Journals (Sweden)

    Janette Brezinová

    2009-02-01

    Full Text Available The paper deals with the evaluation of material wear of injection moulds made of aluminium alloy Alumec 89 and copper alloy Moldmax HH in friction couples with plastomer materials with various filler contents. The friction relations in injection moulding were simulated in an adhesion dry wear test using an Amsler machine, with an area contact of the friction couple materials. The wear intensity was evaluated by determination of friction coefficient and relative wearing by the mass loss. Surface morphology changes of evaluated alloys after wear and the thermal conditions in particular friction couples were analysed simultaneously.

  11. Induction Heating System Applied to Injection Moulding of Micro and Nano Structures

    DEFF Research Database (Denmark)

    Menotti, Stefano

    The present Ph.D. thesis contains a study concerning induction heating system applied to injection moulding of micro and nano structures. The overall process chain was considered and investigated during the project including part design, simulation, conventional and non-conventional tooling...... part. In fact one of the main problems in micro injection moulding is the premature freezing of the polymer flow inside the cavity and often is not possible to obtain a full replica of the nano/micro structures embed on the surfaces. Some other defects that can be avoided with the use of an additional...

  12. Simulation and Validation of Injection-Compression Filling Stage of Liquid Moulding with Fast Curing Resins

    Science.gov (United States)

    Martin, Ffion A.; Warrior, Nicholas A.; Simacek, Pavel; Advani, Suresh; Hughes, Adrian; Darlington, Roger; Senan, Eissa

    2018-03-01

    Very short manufacture cycle times are required if continuous carbon fibre and epoxy composite components are to be economically viable solutions for high volume composite production for the automotive industry. Here, a manufacturing process variant of resin transfer moulding (RTM), targets a reduction of in-mould manufacture time by reducing the time to inject and cure components. The process involves two stages; resin injection followed by compression. A flow simulation methodology using an RTM solver for the process has been developed. This paper compares the simulation prediction to experiments performed using industrial equipment. The issues encountered during the manufacturing are included in the simulation and their sensitivity to the process is explored.

  13. Economic trade-offs of additive manufacturing integration in injection moulding process chain

    DEFF Research Database (Denmark)

    Charalambis, Alessandro; Kerbache, Laoucine; Tosello, Guido

    2017-01-01

    Additive Manufacturing has emerged as an innovative set of novel technologies capable of replacing established manufacturing processes due to fabrication of highly complex parts and its continuous improvements of efficiency and cost effectiveness. This study is based on the idea that through...... the creation of synergies between additive and conventional manufacturing technologies it is possible to achieve greater cost advantages and operational benefits than by substituting injection moulding with additive manufacturing. The analysis presented explores the cost advantages that can be secured when...... additive manufacturing is used to support the fabrication of mould inserts for the product development phase of the injection moulding process chain. This study shows that fabrication of soft tooling by mean of AM is economically convenient with a cost reduction between 80% and 90%. Break-even points...

  14. ALGORITHMS FOR THE PROGRAMMING OF FOOTWEAR SOLES MOULDS ON WORKING POSTS OF INJECTION MACHINES

    Directory of Open Access Journals (Sweden)

    LUCA Cornelia

    2014-05-01

    Full Text Available The moulds stock necessary for realization in rhythmically conditions, a certain volume of footwear soles depends on some criterions such as: the range of soles for footwear volume daily realized, the sizes structure of those soles for footwear and, respectively, the sizes tally, the technological cycle for an used mould depending on the equipment efficiency, the provide necessity of spare moulds, the using and fixing conditions etc. From the efficiency point of view, the equipments may have two working posts, or more working posts (always, an even number, as 6, 12, 24, 40 posts. Footwear soles manufacturing takes into account the percentage distribution of the size numbers of the size series. When o portative assembly is used for the manufacturing of the footwear soles using the injection with “n” working posts, it is very important an optimum distribution of the working posts. The disadvantages of these equipments are the situations of the no equilibrium programming of the moulds, so that, in one time, some working posts spread out of the work. The paper presents some practical and theoretical solutions for moulds stock programming in portative assembly for footwear soles injection, so that an optimum equilibrium degree of the working posts will obtain

  15. Performance Evaluation of a Software Engineering Tool for Automated Design of Cooling Systems in Injection Moulding

    DEFF Research Database (Denmark)

    Jauregui-Becker, Juan M.; Tosello, Guido; van Houten, Fred J.A.M.

    2013-01-01

    This paper presents a software tool for automating the design of cooling systems for injection moulding and a validation of its performance. Cooling system designs were automatically generated by the proposed software tool and by applying a best practice tool engineering design approach. The two...

  16. Micro Engineering: Experiments conducted on the use of polymeric materials in micro injection moulding

    DEFF Research Database (Denmark)

    Griffiths, Christian; Tosello, Guido; Nestler, Joerg

    2008-01-01

    To advance micro injection moulding it is necessary to study systematically the factors affecting process and tooling reliability. This paper reviews the main findings of Cardiff Universities 4M and SEMOFS research in this field. In particular, the factors affecting the manufacturability of micro...

  17. Simultaneous Replication of both Refractive and Diffractive Optical Components using Electroformed Tools and Injection Moulding

    DEFF Research Database (Denmark)

    Tang, Peter Torben; Christensen, Thomas R.

    2003-01-01

    This research project has demonstrated that with carefully selected processes it is possible to fabricate tools for injection moulding of both diffractive and refractive optical components. The fabrication procedure is based on an aluminium disc on which selected optical components (gratings and ...

  18. Modelling the deformation of nickel foil during manufacturing of nanostructures on injection moulding tool inserts

    DEFF Research Database (Denmark)

    Sonne, Mads Rostgaard; Cech, Jiri; Pranov, H.

    2016-01-01

    In the present work, a manufacturing process for transferring nanostructures from a glass wafer, to a double-curvedinsert for injection moulding is demonstrated. A nanostructure consisting of sinusoidal cross-gratings with a period of 426 nm issuccessfully transferred to hemispheres on an aluminium...

  19. Microstructure, surface topography and mechanical properties of slip cast and powder injection moulded microspecimens made of zirconia

    International Nuclear Information System (INIS)

    Auhorn, M.; Kasanicka, B.; Beck, T.; Schulze, V.; Loehe, D.

    2003-01-01

    Investigations on ceramic microspecimens made of Y 2 O 3 -stabilized ZrO 2 produced by slip casting or micro powder injection moulding are introduced. During the production of the microspecimens, feedstocks and sintering conditions were varied. Differently moulded specimens were examined with respect to their microstructure and surface topography using light microscopy, scanning electron microscopy (SEM) and confocal white light microscopy. Additionally, the mechanical characteristics were investigated by three-point bending tests using a micro universal testing device. The statistical analysis was realised by means of the Weibull theory and interpreted by the aid of SEM images of fracture surfaces. This research allowed to understand correlations between different feedstocks used, process parameters like the sintering conditions applied and the resulting characteristics as well as material properties of the microspecimens. These results could be used to improve the production process. (orig.)

  20. Two-component injection moulding simulation of ABS-POM micro structured surfaces

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Islam, Aminul

    2013-01-01

    Multi-component micro injection moulding (μIM) processes such as two-component (2k) μIM are the key technologies for the mass fabrication of multi-material micro products. 2k-μIM experiments involving a miniaturized test component with micro features in the sub-mm dimensional range and moulding...... a pair of thermoplastic materials (ABS and POM) were conducted. Three dimensional process simulations based on the finite element method have been performed to explore the capability of predicting filling pattern shape at component-level and surface micro feature-level in a polymer/polymer overmoulding...

  1. Advancements on the simulation of the micro injection moulding process

    DEFF Research Database (Denmark)

    Marhöfer, David Maximilian; Tosello, Guido; Hansen, Hans Nørgaard

    2013-01-01

    injection molding, because they are developed for macro plastic parts and they are therefore limited in the capability of modeling the polymer flow in micro cavities properly. However, new opportunities for improved accuracy have opened up due to current developments of the simulation technology. Hence, new......Process simulations are applied in micro injection molding with the same purpose as in conventional injection molding: aiming at optimization and support of the design of mold, inserts, plastic products, and the process itself. Available software packages are however not well suited for micro...

  2. Development of Metal/Polymer Mixtures Dedicated to Macro and Micro powder Injection Moulding : Experiments and Simulations

    International Nuclear Information System (INIS)

    Quinard, C.; Barriere, T.; Gelin, J. C.; Song, J. P.; Cheng, Z. Q.; Liu, B. S.

    2007-01-01

    Important research tasks at ENSMM/LMA are concerned for the development of mixtures of fine powders associated to polymer binders dedicated to the powder injection moulding (PIM) and to the powder injection micro-moulding (μPIM) in accordance with many works already carried out with different feedstock suppliers dedicated to the macro-components. These research tasks are completed with the simulations of injection and sintering for solid state diffusion for to validate the mumerical models

  3. Effects of carbon fibres on the life cycle assessment of additively manufactured injection moulding inserts for rapid prototyping

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael

    2017-01-01

    properties and lifetime. The additively manufactured inserts are compared to the standard materials steel, aluminium and brass. The investigated part of the production and prototyping phase considers the insert itself, the moulded part, and resulting waste material of the injection moulding process....

  4. Comparison of conventional Injection Mould Inserts to Additively Manufactured Inserts using Life Cycle Assessment

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Bey, Niki; Mischkot, Michael

    2016-01-01

    Polymer Additive Manufacturing can be used to produce soft tooling inserts for injection moulding. Compared to conventional tooling, the energy and time consumption during production are significantly lower. As the life time of such inserts is significantly shorter than the life time of traditional...... of their potential environmental impact and yield throughout the development and pilot phase. Insert geometry is particularly advantageous for pilot production and small production sizes. In this research, Life Cycle Assessment is used to compare the environmental impact of soft tooling by Additive Manufacturing...... (using Digital Light Processing) and three traditional methods for the manufacture of inserts (milling of brass, steel, and aluminium) for injection moulds during the pre-production phase....

  5. Injection moulding of plastic parts with laser textured surfaces with optical applications

    Science.gov (United States)

    Pina-Estany, J.; García-Granada, A. A.; Corull-Massana, E.

    2018-05-01

    The purpose of this work is to manufacture micro and nanotextured surfaces on plastic injection moulds with the aim of replicating them and obtaining plastic parts with optical applications. Different patterns are manufactured with nanosecond and femtosecond lasers in order to obtain three different optical applications: (i) homogeneous light diffusion (ii) 1D light directionality and (iii) 2D light directionality. Induction heating is used in the injections in order to improve the textures degree of replication. The steel mould and the plastic parts are analyzed with a confocal/focus variation microscope and with a surface roughness tester. A mock-up and a luminance camera are used to evaluate the homogeneity and luminance of the homogeneous light diffusion application in comparison with the current industrial solutions.

  6. Modelling injection moulding machines for micro manufacture applications through functional analysis

    DEFF Research Database (Denmark)

    Fantoni, G.; Tosello, Guido; Gabelloni, D.

    2012-01-01

    The paper presents the analysis of an injection moulding machine using functional analysis to identify both its critical components and possible working problems when such a machine is employed for the production of polymer-based micro products. The step-by-step procedure starts from the study...... of the process phases of a machine and then it employs functional analysis to decompose the phases and attributes functions to part features. Part features are subsequently analyzed to understand the causal chains bringing either to the desired behaviour or to failures to avoid. The assessment of the design...... solution is finally performed by gathering quantitative data from experiments. The case study investigates the design motivations and functional drivers of a micro injection moulding machine. The analysis allows identifying the correlations between failures and advantages with the design of the machine...

  7. Computation of Thermal Development in Injection Mould Filling, based on the Distance Model

    OpenAIRE

    Andersson, Per-Åke

    2002-01-01

    The heat transfer in the filling phase of injection moulding is studied, based on Gunnar Aronsson’s distance model for flow expansion ([Aronsson], 1996). The choice of a thermoplastic materials model is motivated by general physical properties, admitting temperature and pressure dependence. Two-phase, per-phase-incompressible, power-law fluids are considered. The shear rate expression takes into account pseudo-radial flow from a point inlet. Instead of using a finite element (FEM) solver for ...

  8. The Use of Particulate Injection Moulding for Fabrication of Sports and Leisure Equipment from Titanium Metals

    Directory of Open Access Journals (Sweden)

    Paul D. Ewart

    2018-02-01

    Full Text Available Advanced materials such as metal alloys, carbon fibre composites and engineered polymers have improved athlete performances in all sporting applications. Advances in manufacturing has enabled increases in design complexity and the ability to rapidly prototype bespoke products using additive manufacturing also known as 3D printing. Another recent fabrication method widely used by medical, electronics and armaments manufacturers is particulate injection moulding. This process uses exact quantities of the required material, in powder form, minimising resource and energy requirements in comparison to conventional manufacturing techniques. The process utilises injection moulding techniques and tooling methods developed and used in the plastics industry. It can produce highly complex component geometries with excellent repeatability and reduced cost where volume manufacturing is required. This is especially important when considering materials such as titanium that are not only expensive in comparison to other metals but are difficult to process by regular machining and fabrication methods. This work presents a review of titanium use in the sporting sector with a focus on sporting devices and equipment. It also proposes that the sports engineering sector could increase performance and enable improvements in safety by switching to design methods appropriate to processing via the particulate injection moulding route.

  9. Integrating measuring uncertainty of tactile and optical coordinate measuring machines in the process capability assessment of micro injection moulding

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Gasparin, Stefania

    2010-01-01

    Process capability of micro injection moulding was investigated in this paper by calculating the Cp and Cpk statistics. Uncertainty of both optical and tactile measuring systems employed in the quality control of micro injection moulded products was assessed and compared with the specified...... tolerances. Limits in terms of manufacturing process capability as well as of suitability of such measuring systems when employed for micro production inspection were quantitatively determined....

  10. Utilizing of inner porous structure in injection moulds for application of special cooling method

    International Nuclear Information System (INIS)

    Seidl, M; Bobek, J; Habr, J; Běhálek, L; Šafka, J; Nováková, I

    2016-01-01

    The article is focused on impact evaluation of controlled inner structure of production tools and new cooling method on regulation of thermal processes for injection moulding technology. The mould inserts with porous structure were cooled by means of liquid CO 2 which is very progressive cooling method and enables very fast and intensive heat transfer among the plastic product, the production tool and cooling medium. The inserts were created using rapid prototype technology (DLSM) and they had a bi-component structure consisting of thin compact surface layer and defined porous inner structure of open cell character where liquid CO 2 was flowing through. This analyse includes the evaluation of cooling efficiency for different inner structures and different time profiles for dosing of liquid CO 2 into the porous structure. The thermal processes were monitored using thermocouples and IR thermal analyse of product surface and experimental device. Intensive heat removal influenced also the final structure and the shape and dimensional accuracy of the moulded parts that were made of semi-crystalline polymer. The range of final impacts of using intensive cooling method on the plastic parts was defined by DSC and dimensional analyses. (paper)

  11. Cycle time improvement for plastic injection moulding process by sub groove modification in conformal cooling channel

    Science.gov (United States)

    Kamarudin, K.; Wahab, M. S.; Batcha, M. F. M.; Shayfull, Z.; Raus, A. A.; Ahmed, Aqeel

    2017-09-01

    Mould designers have been struggling for the improvement of the cooling system performance, despite the fact that the cooling system complexity is physically limited by the fabrication capability of the conventional tooling methods. However, the growth of Solid Free Form Technology (SFF) allow the mould designer to develop more than just a regular conformal cooling channel. Numerous researchers demonstrate that conformal cooling channel was tremendously given significant result in the improvement of productivity and quality in the plastic injection moulding process. This paper presents the research work that applies the passive enhancement method in square shape cooling channel to enhance the efficiency of cooling performance by adding the sub groove to the cooling channel itself. Previous design that uses square shape cooling channel was improved by adding various numbers of sub groove to meet the best sub groove design that able reduced the cooling time. The effect of sub groove design on cooling time was investigated by Autodesk Modlflow Insight software. The simulation results showed that the various sub groove designs give different values to ejection time. The Design 7 showed the lowest value of ejection time with 24.3% increment. The addition of sub groove significantly increased a coolant velocity and a rate of heat transfer from molten plastic to coolant.

  12. Laser confocal microscope noise evaluation on injection compression moulded (ICM) transparent polymer Fresnel lenses

    DEFF Research Database (Denmark)

    Loaldi, D.; Calaon, Matteo; Quagliotti, Danilo

    , on an injection compression moulded (ICM) Fresnel lens, is defined. A set of two different objectives is considered, i.e. a standard series (SO), against a long working distance one (LWD); two different magnifications objectives, 50x and 100x and the use or not of a dark environment. The noise evaluation...... are measuring working distance, objective magnification and room lighting. The result confirms a strong difference of noise, using the considered objectives. The most interesting result is that the performance of SO 50x objective is better than LWD 100x....

  13. Fabrication and modelling of injection moulded all-polymer capillary microvalves for passive microfluidic control

    International Nuclear Information System (INIS)

    Kistrup, Kasper; Østergaard, Peter Friis; Taboryski, Rafael; Wolff, Anders; Hansen, Mikkel Fougt; Haugshøj, Kenneth Brian; Poulsen, Carl Esben

    2014-01-01

    Rapid prototyping is desirable when developing products. One example of such a product is all-polymer, passive flow controlled lab-on-a-chip systems that are preferential when developing low-cost disposable chips for point-of-care use. In this paper we investigate the following aspects of going from rapid prototyping to pilot (mass) production. (1) Fabrication of an all-polymer microfluidic system using a rapid prototyped master insert for injection moulding and ultrasonic welding, including a systematic experimental characterisation of chip featured geometric capillary microvalve test structures. (2) Numerical modelling of the microvalve burst pressures. Numerical modelling of burst pressures is challenging due to its non-equilibrium nature. We have implemented and tested the level-set method modified with a damped driving term and show that the introduction of the damping term leads to numerically robust results with limited computational demands and a low number of iterations. Numerical and simplified analytical results are validated against the experimental results. We find that injection moulding and ultrasonic welding are effective for chip production and that the experimental burst pressures could be estimated with an average accuracy of 5% using the presented numerical model. (paper)

  14. Investigation of Plasma Treatment on Micro-Injection Moulded Microneedle for Drug Delivery

    Directory of Open Access Journals (Sweden)

    Karthik Nair

    2015-10-01

    Full Text Available Plasma technology has been widely used to increase the surface energy of the polymer surfaces for many industrial applications; in particular to increase in wettability. The present work was carried out to investigate how surface modification using plasma treatment modifies the surface energy of micro-injection moulded microneedles and its influence on drug delivery. Microneedles of polyether ether ketone and polycarbonate and have been manufactured using micro-injection moulding and samples from each production batch have been subsequently subjected to a range of plasma treatment. These samples were coated with bovine serum albumin to study the protein adsorption on these treated polymer surfaces. Sample surfaces structures, before and after treatment, were studied using atomic force microscope and surface energies have been obtained using contact angle measurement and calculated using the Owens-Wendt theory. Adsorption performance of bovine serum albumin and release kinetics for each sample set was assessed using a Franz diffusion cell. Results indicate that plasma treatment significantly increases the surface energy and roughness of the microneedles resulting in better adsorption and release of BSA.

  15. Paraffin wax removal from metal injection moulded cocrmo alloy compact by solvent debinding process

    Science.gov (United States)

    Dandang, N. A. N.; Harun, W. S. W.; Khalil, N. Z.; Ahmad, A. H.; Romlay, F. R. M.; Johari, N. A.

    2017-10-01

    One of the most crucial and time consuming phase in metal injection moulding (MIM) process is “debinding”. These days, in metal injection moulding process, they had recounted that first debinding practice was depend on thermal binder degradation, which demanding more than 200 hours for complete removal of binder. Fortunately, these days world had introduced multi-stage debinding techniques to simplified the debinding time process. This research study variables for solvent debinding which are temperature and soaking time for samples made by MIM CoCrMo powder. Since wax as the key principal in the binder origination, paraffin wax will be removed together with stearic acid from the green bodies. Then, debinding process is conducted at 50, 60 and 70°C for 30-240 minutes. It is carried out in n-heptane solution. Percentage weight loss of the binder were measured. Lastly, scanning electron microscope (SEM) analysis and visual inspection were observed for the surface of brown compact. From the results, samples debound at 70°C exhibited a significant amount of binder loss; nevertheless, sample collapse, brittle surface and cracks were detected. But, at 60°C temperature and time of 4 hours proven finest results as it shows sufficient binder loss, nonappearance of surface cracks and easy to handle. Overall, binder loss is directly related to solvent debinding temperature and time.

  16. Experimental investigation on shrinkage and surface replication of injection moulded ceramic parts

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian

    2014-01-01

    Ceramic moulded parts are increasingly being used in advanced components and devices due to their unprecedented material and performance attributes. The surface finish, replication quality and material shrinkage are of immense importance for moulded ceramic parts intended for precision applications....... The current paper presents a thorough investigation on the process of ceramic moulding where it systematically characterizes the surface replication and shrinkage behaviours of precision moulded ceramic components. The test parts are moulded from Catamold TZP-A which is Y2O3-stabilised ZrO2 having widespread...... distribution for the moulded ceramic parts is presented....

  17. Injection moulded microneedle sensor for real-time wireless pH monitoring.

    Science.gov (United States)

    Mirza, Khalid B; Zuliani, Claudio; Hou, Benjamin; Ng, Fu Siong; Peters, Nicholas S; Toumazou, Christofer

    2017-07-01

    This paper describes the development of an array of individually addressable pH sensitive microneedles using injection moulding and their integration within a portable device for real-time wireless recording of pH distributions in biological samples. The fabricated microneedles are subjected to gold patterning followed by electrodeposition of iridium oxide to sensitize them to 0.07 units of pH change. Miniaturised electronics suitable for the sensors readout, analog-to-digital conversion and wireless transmission of the potentiometric data are embodied within the device, enabling it to measure real-time pH of soft biological samples such as muscles. In this paper, real-time recording of the cardiac pH distribution, during ischemia followed by reperfusion cycles in cardiac muscles of male Wistar rats has been demonstrated by using the microneedle array.

  18. Fabrication and modelling of injection moulded all-polymer capillary microvalves for passive microfluidic control

    DEFF Research Database (Denmark)

    Kistrup, Kasper; Poulsen, Carl Esben; Østergaard, Peter Friis

    2014-01-01

    Rapid prototyping is desirable when developing products. One example of such a product is all-polymer, passive flow controlled lab-on-a-chip systems that are preferential when developing low-cost disposable chips for point-of-care use. In this paper we investigate the following aspects of going...... from rapid prototyping to pilot (mass) production. (1) Fabrication of an all-polymer microfluidic system using a rapid prototyped master insert for injection moulding and ultrasonic welding, including a systematic experimental characterisation of chip featured geometric capillary microvalve test...... structures. (2) Numerical modelling of the microvalve burst pressures. Numerical modelling of burst pressures is challenging due to its non-equilibrium nature. We have implemented and tested the level-set method modified with a damped driving term and show that the introduction of the damping term leads...

  19. On the use of titanium hydride for powder injection moulding of titanium-based alloys

    International Nuclear Information System (INIS)

    Carrenoo-Morelli, E.; Bidaux, J.-E.

    2009-01-01

    Full text: Titanium and titanium-based alloys are excellent materials for a number of engineering applications because of their high strength, lightweight, good corrosion resistance, non magnetic characteristic and biocompatibility. The current processing steps are usually costly, and there is a growing demand for net-shape solutions for manufacturing parts of increasing complexity. Powder injection moulding is becoming a competitive alternative, thanks to the advances in production of good quality base-powders, binders and sintering facilities. Titanium hydride powders, have the attractiveness of being less reactive than fine titanium powders, easier to handle, and cheaper. This paper summarizes recent advances on PIM of titanium and titanium alloys from TiH2 powders, including shape-memory NiTi alloys. (author)

  20. Modeling of Cooling Channels of Injection Mould using Functionally Graded Material

    International Nuclear Information System (INIS)

    Shin, Ki Hoon

    2011-01-01

    The cycle time in injection moulding greatly depends on the cooling time of the plastic part that is controlled by cooling channels. Cooling channels are required to facilitate the heat transfer rate from the die to the coolant without reducing the strength of the die. Employing layered manufacturing techniques (LMT), a die embedding conformal cooling channels can be fabricated directly while conventional cooling channels are usually made of straight drilled hole. Meanwhile, H13 tool steel is widely used as the die material because of its high thermal resistance and dimensional stability. However, H13 with a low thermal conductivity is not efficient for certain part geometries. In this context, the use of functionally graded materials (FGMs) between H13 and copper may circumvent a tradeoff between the strength and the heat transfer rate. This paper presents a method for modeling of conformal cooling channels made of FGMs

  1. The influence of particle size distribution on the properties of metal-injection-moulded 17-4 PH stainless steel

    CSIR Research Space (South Africa)

    Seerane, Mandy

    2016-10-01

    Full Text Available Metal injection moulding (MIM) is a near-net-shaping powder metallurgy technique suitable for the cost-effective mass production of small and complex components. In this paper, the effects of the metal powder particle size on the final properties...

  2. Modelling the deformations during the manufacturing of nanostructures on non-planar surfaces for injection moulding tool inserts

    DEFF Research Database (Denmark)

    Sonne, M. R.; Cech, J.; Pranov, H.

    2016-01-01

    This paper presents a new manufacturing process for transferring nanostructures from a glass wafer to a curved aluminium insert for polymer injection moulding. A nanostructure consisting of sinusoidal cross-gratings with a period of 426 nm is successfully transferred to hemispheres with different...

  3. Characterization and analysis of micro channels and sub-micron surface roughness of injection moulded microfluidic systems using optical metrology

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2012-01-01

    measuring machine and a white light interferometer respectively. The effect of the dimensional scale range on the micro/nano features replication was evaluated and it was found to be the dominant parameter if compared with the effect of the other process-related parameters investigated (melt and mould...

  4. Characterization and analysis of micro channels and sub-micron surface roughness of injection moulded microfluidic systems using optical metrology

    DEFF Research Database (Denmark)

    Tosello, Guido; Marinello, Francesco; Hansen, Hans Nørgaard

    2009-01-01

    measuring machine and a white light interferometer respectively. The effect of the dimensional scale range on the micro/nano features replication was evaluated and it was found to be the dominant parameter if compared with the effect of the other process-related parameters investigated (melt and mould...

  5. Study of injection moulded long glass fibre-reinforced polypropylene and the effect on the fibre length and orientation distribution

    Science.gov (United States)

    Parveeen, B.; Caton-Rose, P.; Costa, F.; Jin, X.; Hine, P.

    2014-05-01

    Long glass fibre (LGF) composites are extensively used in manufacturing to produce components with enhanced mechanical properties. Long fibres with length 12 to 25mm are added to a thermoplastic matrix. However severe fibre breakage can occur in the injection moulding process resulting in shorter fibre length distribution (FLD). The majority of this breakage occurs due to the melt experiencing extreme shear stress during the preparation and injection stage. Care should be taken to ensure that the longer fibres make it through the injection moulding process without their length being significantly degraded. This study is based on commercial 12 mm long glass-fibre reinforced polypropylene (PP) and short glass fibre Nylon. Due to the semi-flexiable behaviour of long glass fibres, the fibre orientation distribution (FOD) will differ from the orientation distribution of short glass fibre in an injection molded part. In order to investigate the effect the change in fibre length has on the fibre orientation distribution or vice versa, FOD data was measured using the 2D section image analyser. The overall purpose of the research is to show how the orientation distribution chnages in an injection moulded centre gated disc and end gated plaque geometry and to compare this data against fibre orientation predictions obtained from Autodesk Moldflow Simulation Insight.

  6. Mechanical properties test and microstructure analysis of polyoxymethylene (POM) micro injection moulded standard parts

    DEFF Research Database (Denmark)

    Tosello, Guido; Lucchetta, Giovanni; Hansen, Hans Nørgaard

    2009-01-01

    to factorial plans, in which the factors of interest were mould temperature, melt temperature and dimensional range of the specimen (i.e. macro and micro parts). Micro structure analysis was performed by means of plastography techniques and revealed that high mould and melt temperatures resulted on a thin skin...

  7. Report on best practice for improved μ-IM injection moulding simulation

    DEFF Research Database (Denmark)

    Tosello, Guido; Costa, Franco; Hansen, Hans Nørgaard

    2010-01-01

    Data analysis and simulations on micro-moulding experiments have been conducted. Micro moulding simulations have been executed taking into account actual processing conditions implementation in the software. Numerous aspects of the simulation set-up have been considered in order to improve the si...

  8. Micro Injection Moulding High Accuracy Three-Dimensional Simulations and Process Control

    DEFF Research Database (Denmark)

    Tosello, Guido; Costa, F.S.; Hansen, Hans Nørgaard

    2011-01-01

    Data analysis and simulations of micro‐moulding experiments have been conducted. Micro moulding simulations have been executed by implementing in the software the actual processing conditions. Various aspects of the simulation set‐up have been considered in order to improve the simulation accurac...

  9. LIMITED RUN PRODUCTION USING ALUMIDE® TOOLING FOR THE PLASTIC INJECTION MOULDING PROCESS#1

    Directory of Open Access Journals (Sweden)

    J. Combrinck

    2012-01-01

    Full Text Available

    ENGLISH ABSTRACT: Existing techniques for the production of conventional steel tooling for plastic injection moulding are expensive and time-consuming. As a result, many new products often do not advance beyond the prototype stage. This paper describes an investigation into the possibility of using laser sintered Alumide® (an aluminium-filled nylon material in a novel alternative process for producing hybrid rapid tooling tools. Initial experiments performed by researchers at the Central University of Technology have shown excellent results. An Alumide® tool can be manufactured in a shorter time and at a significantly lower cost than the same size direct metal laser sintered tool.

    AFRIKAANSE OPSOMMING: Bestaande tegnieke vir die vervaardiging van konvensionele staal gietstukke vir die plastiek spuit-giet proses is duur en tydrowend. Die gevolg hiervan is dat baie nuwe produkte nie verder as die prototipe stadium vorder nie. Hierdie artikel ondersoek die moontlikheid om laser gesinterde Alumide® (aluminium gevulde nylon materiaal in ’n nuwe benadering as ’n alternatiewe proses vir die vervaardiging van snel hibried-gietvorms te gebruik. Aanvanklike eksperimente uitgevoer deur navorsers aan die Sentrale Universiteit vir Tegnologie het uitstekende resultate gelewer. ’n Alumide® gietvorm kan vinniger en goedkoper vervaardig word as dieselfde grootte direk metaal gesinterde gietvorm.

  10. Ultrasound based monitoring of the injection moulding process - Methods, applications and limitations

    International Nuclear Information System (INIS)

    Praher, B.; Straka, K.; Usanovic, J.; Steinbichler, G.

    2014-01-01

    We developed novel non-invasive ultrasound based systems for the measurement of temperature distributions in the screw-ante chamber, the detection of unmelted granules and for the monitoring of the plasticizing process along the screw channel. The temperature of the polymer melt stored in the screw ante-chamber after the plasticization should be homogeneous. However, in reality the polymer melt in the screw ante-chamber is not homogeneous. Due to the fact the sound velocity in a polymer melt is temperature depending, we developed a tomography system using the measured transit times of ultrasonic pulses along different sound paths for calculating the temperature distribution in radial direction of a polymer melt in the screw ante-chamber of an injection moulding machine. For the detection of unmelted granules in the polymer melt we implemented an ultrasound transmission measurement. By analyzing the attenuation of the received pulses it is possible to detect unwanted inclusions. For the monitoring of the plasticizing process in the channels of the screw an ultrasonic pulse is transmitted into the barrel. By analyzing the reflected pulses it is possible to estimate solid bed and melt regions in the screw channel. The proposed systems were tested for accuracy and validity by simulations and test measurements

  11. Debinding behaviour of a water soluble PEG/PMMA binder for Ti metal injection moulding

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Gang [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Cao, Peng, E-mail: p.cao@auckland.ac.nz [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Wen, Guian [Department of Chemical and Materials Engineering, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand); Edmonds, Neil [School of Chemical Science, The University of Auckland, Private Bag 92019, Auckland 1142 (New Zealand)

    2013-05-15

    Polyethylene glycol (PEG) has been becoming a common component in the design of water soluble binder systems for metal injection moulding. Similar to solvent debinding, PEG can be leached out by water and the mechanism of debinding was proposed in the literature with somehow misleading information about the debinding mechanism, particularly about the formation of PEG gel. This work investigates the debinding behaviours of a PEG-based binder in titanium compacts. Titanium powder is formulated with PEG, poly(methyl methacrylate) (PMMA) and stearic acid (SA) to formulate titanium feedstock. To determine the debinding kinetics, the PEG removal percentages are measured at three different temperatures and for various specimen thicknesses. A mathematic model based on diffusion-controlled debinding process is established. The evolution of porous microstructure during the water debinding process is observed using scanning electron microscopy. Based on these observations, a water debinding mechanism for titanium alloy compacts formulated with PEG-based binders is proposed. - Highlights: ► The water-debinding behaviours of the PEG binder system were investigated. ► PEG dissolution and transportation, and the pore structure development. ► A water debinding mechanism of PEG-based binders is proposed. ► Incorrect explanation of PEG gelling in the literature is corrected. ► Correction/modification made as per the reviewers' comments and suggestions.

  12. Molecular orientation of individual LCP particles in injection-moulded PPS/LCP blends

    Directory of Open Access Journals (Sweden)

    Kestenbach H.-J.

    2003-01-01

    Full Text Available Polarized light microscopy was used to investigate the presence of preferred molecular orientation in the LCP phase of PPS/LCP blends after injection moulding. Normal birefringence effects appeared to be complicated by artifacts due to sample preparation and by the complex nature of polarized light transmission through a multicomponent sample. It was found, however, that, during low-temperature cutting of optically transparent thin sections on a standard microtome, individual LCP particles could be separated from the PPS matrix, and their birefringence analyzed separately. Preferred orientation was detected only in LCP fibrils which dominated in skin regions, but not in droplet-shaped particles which had formed in core regions. Quantitative measurements indicated that the molecular orientation of the fibrils increased linearly with their length-to-diameter aspect ratios which ranged from 15 to 50. Even for the highest aspect ratios, however, the degree of orientation was always less than that which could easily be introduced into pure LCP thin-film samples by manual shearing.

  13. In vitro bioactivity of micro metal injection moulded stainless steel with defined surface features

    Directory of Open Access Journals (Sweden)

    C Brose

    2012-05-01

    Full Text Available Micrometre- and nanometre-scale surface structuring with ordered topography features may dramatically enhance orthopaedic implant integration. In this study we utilised a previously optimised micron metal injection moulding (µ-MIM process to produce medical grade stainless steel surfaces bearing micrometre scale, protruding, hemispheres of controlled dimensions and spatial distribution. Additionally, the structured surfaces were characterised by the presence of submicrometre surface roughness resulting from metal grain boundary formation. Following cytocompatibility (cytotoxicity evaluation using 3T3 mouse fibroblast cell line, the effect on primary human cell functionality was assessed focusing on cell attachment, shape and cytoskeleton conformation. In this respect, and by day 7 in culture, significant increase in focal adhesion size was associated with the microstructured surfaces compared to the planar control. The morphological conformation of the seeded cells, as revealed by fluorescence cytoskeleton labelling, also appeared to be guided in the vertical dimension between the hemisphere bodies. Quantitative evaluation of this guidance took place using live cytoplasm fluorescence labelling and image morphometry analysis utilising both, compactness and elongation shape descriptors. Significant increase in cell compactness was associated with the hemisphere arrays indicating collective increase in focused cell attachment to the hemisphere bodies across the entire cell population. Micrometre-scale hemisphere array patterns have therefore influenced cell attachment and conformation. Such influence may potentially aid in enhancing key cellular events such as, for example, neo-osteogenesis on implanted orthopaedic surfaces.

  14. Development of crayfish bio-based plastic materials processed by small-scale injection moulding.

    Science.gov (United States)

    Felix, Manuel; Romero, Alberto; Cordobes, Felipe; Guerrero, Antonio

    2015-03-15

    Protein has been investigated as a source for biodegradable polymeric materials. This work evaluates the development of plastic materials based on crayfish and glycerol blends, processed by injection moulding, as a fully biodegradable alternative to conventional polymer-based plastics. The effect of different additives, namely sodium sulfite or bisulfite as reducing agents, urea as denaturing agent and L-cysteine as cross-linking agent, is also analysed. The incorporation of any additive always yields an increase in energy efficiency at the mixing stage, but its effect on the mechanical properties of the bioplastics is not so clear, and even dampened. The additive developing a greater effect is L-cysteine, showing higher Young's modulus values and exhibiting a remnant thermosetting potential. Thus, processing at higher temperature yields a remarkable increase in extensibility. This work illustrates the feasibility of crayfish-based green biodegradable plastics, thereby contributing to the search for potential value-added applications for this by-product. © 2014 Society of Chemical Industry.

  15. Debinding and Sintering of an Injection-Moulded Hypereutectic Al–Si Alloy

    Directory of Open Access Journals (Sweden)

    Jiaqi Ni

    2018-05-01

    Full Text Available Hypereutectic Al–Si (20 wt.% alloy parts were fabricated by employing a powder injection moulding (PIM technique with a developed multi-component binder system composed of high-density polyethylene (35 wt.%, carnauba wax (62 wt.% and stearic acid (3 wt.%. The feedstocks contained 83 wt.% metal powders. The debinding process was carried out by a combination of solvent extraction and thermal decomposition. The effects of solvent debinding variables such as kind of solvents, debinding temperatures and time, and the bulk surface area to volume ratios on the debinding process were investigated. Thermal debinding and the subsequent sintering process were carried out in a heating sequence under a nitrogen atmosphere. The influences of sintering temperature and sintering time on the mechanical properties and structure were considered. Under the optimal sintering condition, sintering at 550 °C for 3 h, the final sintering parts were free of distortion and exhibited good mechanical properties. Relative sintered density, Brinell hardness, and tensile strength were ~95.5%, 58 HBW and ~154, respectively.

  16. Debinding and Sintering of an Injection-Moulded Hypereutectic Al⁻Si Alloy.

    Science.gov (United States)

    Ni, Jiaqi; Yu, Muhuo; Han, Keqing

    2018-05-16

    Hypereutectic Al⁻Si (20 wt.%) alloy parts were fabricated by employing a powder injection moulding (PIM) technique with a developed multi-component binder system composed of high-density polyethylene (35 wt.%), carnauba wax (62 wt.%) and stearic acid (3 wt.%). The feedstocks contained 83 wt.% metal powders. The debinding process was carried out by a combination of solvent extraction and thermal decomposition. The effects of solvent debinding variables such as kind of solvents, debinding temperatures and time, and the bulk surface area to volume ratios on the debinding process were investigated. Thermal debinding and the subsequent sintering process were carried out in a heating sequence under a nitrogen atmosphere. The influences of sintering temperature and sintering time on the mechanical properties and structure were considered. Under the optimal sintering condition, sintering at 550 °C for 3 h, the final sintering parts were free of distortion and exhibited good mechanical properties. Relative sintered density, Brinell hardness, and tensile strength were ~95.5%, 58 HBW and ~154, respectively.

  17. An automated optofluidic biosensor platform combining interferometric sensors and injection moulded microfluidics.

    Science.gov (United States)

    Szydzik, C; Gavela, A F; Herranz, S; Roccisano, J; Knoerzer, M; Thurgood, P; Khoshmanesh, K; Mitchell, A; Lechuga, L M

    2017-08-08

    A primary limitation preventing practical implementation of photonic biosensors within point-of-care platforms is their integration with fluidic automation subsystems. For most diagnostic applications, photonic biosensors require complex fluid handling protocols; this is especially prominent in the case of competitive immunoassays, commonly used for detection of low-concentration, low-molecular weight biomarkers. For this reason, complex automated microfluidic systems are needed to realise the full point-of-care potential of photonic biosensors. To fulfil this requirement, we propose an on-chip valve-based microfluidic automation module, capable of automating such complex fluid handling. This module is realised through application of a PDMS injection moulding fabrication technique, recently described in our previous work, which enables practical fabrication of normally closed pneumatically actuated elastomeric valves. In this work, these valves are configured to achieve multiplexed reagent addressing for an on-chip diaphragm pump, providing the sample and reagent processing capabilities required for automation of cyclic competitive immunoassays. Application of this technique simplifies fabrication and introduces the potential for mass production, bringing point-of-care integration of complex automated microfluidics into the realm of practicality. This module is integrated with a highly sensitive, label-free bimodal waveguide photonic biosensor, and is demonstrated in the context of a proof-of-concept biosensing assay, detecting the low-molecular weight antibiotic tetracycline.

  18. Debinding behaviour of a water soluble PEG/PMMA binder for Ti metal injection moulding

    International Nuclear Information System (INIS)

    Chen, Gang; Cao, Peng; Wen, Guian; Edmonds, Neil

    2013-01-01

    Polyethylene glycol (PEG) has been becoming a common component in the design of water soluble binder systems for metal injection moulding. Similar to solvent debinding, PEG can be leached out by water and the mechanism of debinding was proposed in the literature with somehow misleading information about the debinding mechanism, particularly about the formation of PEG gel. This work investigates the debinding behaviours of a PEG-based binder in titanium compacts. Titanium powder is formulated with PEG, poly(methyl methacrylate) (PMMA) and stearic acid (SA) to formulate titanium feedstock. To determine the debinding kinetics, the PEG removal percentages are measured at three different temperatures and for various specimen thicknesses. A mathematic model based on diffusion-controlled debinding process is established. The evolution of porous microstructure during the water debinding process is observed using scanning electron microscopy. Based on these observations, a water debinding mechanism for titanium alloy compacts formulated with PEG-based binders is proposed. - Highlights: ► The water-debinding behaviours of the PEG binder system were investigated. ► PEG dissolution and transportation, and the pore structure development. ► A water debinding mechanism of PEG-based binders is proposed. ► Incorrect explanation of PEG gelling in the literature is corrected. ► Correction/modification made as per the reviewers' comments and suggestions

  19. Ultrasound based monitoring of the injection moulding process - Methods, applications and limitations

    Energy Technology Data Exchange (ETDEWEB)

    Praher, B., E-mail: bernhard.praher@jku.at, E-mail: klaus.straka@jku.at, E-mail: jesenka.usanovic@jku.at, E-mail: georg.steinbichler@jku.at; Straka, K., E-mail: bernhard.praher@jku.at, E-mail: klaus.straka@jku.at, E-mail: jesenka.usanovic@jku.at, E-mail: georg.steinbichler@jku.at; Usanovic, J., E-mail: bernhard.praher@jku.at, E-mail: klaus.straka@jku.at, E-mail: jesenka.usanovic@jku.at, E-mail: georg.steinbichler@jku.at; Steinbichler, G., E-mail: bernhard.praher@jku.at, E-mail: klaus.straka@jku.at, E-mail: jesenka.usanovic@jku.at, E-mail: georg.steinbichler@jku.at [Institute of Polymer Injection Moulding and Process Automation, Johannes Kepler University Linz (Austria)

    2014-05-15

    We developed novel non-invasive ultrasound based systems for the measurement of temperature distributions in the screw-ante chamber, the detection of unmelted granules and for the monitoring of the plasticizing process along the screw channel. The temperature of the polymer melt stored in the screw ante-chamber after the plasticization should be homogeneous. However, in reality the polymer melt in the screw ante-chamber is not homogeneous. Due to the fact the sound velocity in a polymer melt is temperature depending, we developed a tomography system using the measured transit times of ultrasonic pulses along different sound paths for calculating the temperature distribution in radial direction of a polymer melt in the screw ante-chamber of an injection moulding machine. For the detection of unmelted granules in the polymer melt we implemented an ultrasound transmission measurement. By analyzing the attenuation of the received pulses it is possible to detect unwanted inclusions. For the monitoring of the plasticizing process in the channels of the screw an ultrasonic pulse is transmitted into the barrel. By analyzing the reflected pulses it is possible to estimate solid bed and melt regions in the screw channel. The proposed systems were tested for accuracy and validity by simulations and test measurements.

  20. New processing route for ZrSiO{sub 4} by powder injection moulding using an eco-friendly binder system

    Energy Technology Data Exchange (ETDEWEB)

    Abajo, C.; Jimenez-Morales, A.; Torralba, J. M.

    2015-10-01

    New processing route has been developed for zircon based on powder injection moulding (PIM). Raw zircon powders, obtained from mineral sands, have been processed using a new water soluble binder system composed of PEG and CAB. Water solvent debinding stage has been studied in depth. On one hand, influence of some debinding parameters (temperature, debinding rate, additives and the use of climate chamber) has been tested. On the other hand, new binder systems were tested and compared with previous studied ones. The full PIM process has been carried out. Mixing, injection molding, solvent and thermal debinding and finally sintering, have been performed with the optimal binder system composition. Homogeneity along the process has been assessed by thermo-gravimetric analysis and by density measurements. After sintering, dimensional variation, density and fracture surface obtained after flexural strength test, have been analyzed. A competitive flexural strength has been achieved for injected zircon samples. (Author)

  1. High-Throughput Fabrication of Nanocone Substrates through Polymer Injection Moulding For SERS Analysis in Microfluidic Systems

    DEFF Research Database (Denmark)

    Viehrig, Marlitt; Matteucci, Marco; Thilsted, Anil H.

    analysis. Metal-capped silicon nanopillars, fabricated through a maskless ion etch, are state-of-the-art for on-chip SERS substrates. A dense cluster of high aspect ratio polymer nanocones was achieved by using high-throughput polymer injection moulding over a large area replicating a silicon nanopillar...... structure. Gold-capped polymer nanocones display similar SERS sensitivity as silicon nanopillars, while being easily integrable into a microfluidic chips....

  2. Experimental investigation of the factors influencing the polymer-polymer bond strength during two-component injection moulding

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Bondo, Martin

    2010-01-01

    Two-component injection moulding is a commercially important manufacturing process and a key technology for combining different material properties in a single plastic product. It is also one of most industrially adaptive process chain for manufacturing so-called moulded interconnect devices (MIDs......). Many fascinating applications of two-component or multi-component polymer parts are restricted due to the weak interfacial adhesion of the polymers. A thorough understanding of the factors that influence the bond strength of polymers is necessary for multi-component polymer processing. This paper...... investigates the effects of the process conditions and geometrical factors on the bond strength of two-component polymer parts and identifies the factors which can effectively control the adhesion between two polymers. The effects of environmental conditions on the bond strength are also investigated...

  3. A new approach for the validation of filling simulations in micro injection moulding

    DEFF Research Database (Denmark)

    Gava, Alberto; Tosello, Guido; Lucchetta, Giovanni

    2007-01-01

    to be improved. The main objective of this work is to evaluate whether the present numerical codes are suitable to characterize melt flow patterns in a micro cavity. In order to test the accuracy of the software, real and simulated experiments were performed and used to investigate the filling of a micro moulded...

  4. INFLUENCE OF REGRIND ON PROPERTIES OF PLASTICS PRODUCED BY INJECTION MOULDING

    Directory of Open Access Journals (Sweden)

    Ľudmila Dulebová

    2011-07-01

    Full Text Available The contribution deals with the evaluation of results of selected mechanical tests. Materials Crastin® PBT (with 30 % glass fibre and Celanex® 2004-2 PBT (without filler were used at tests with various percentage of added regrind into basic material. The mechanical properties were obtained by tensile test and Shore hardness test. Utilization of regrind at the production of new moulded parts is important from aspect of reduction plastics waste and pollution abatement of environment.

  5. Physical characterisation of particles and rheological of a heterogeneous system used in low-pressure injection moulding

    International Nuclear Information System (INIS)

    Zampieron, Joao Vicente

    2002-01-01

    The powder injection moulding process is a recent technology, which offers as advantages a high production of complex geometry metal parts, with low cost, where secondary operations of machinery are unnecessary. The main of this thesis was centered on a coarse powders feedstock injection. The process begins with the composition of the mass, that is the combination of metal powders with organic binders. The following steps succeed injection in moulds, debinding, sintering and, if necessary, cleaning. For the formulation of the feedstock it is indispensable the characterisation of the powders. This is little mentioned in the open literature and brings up controversy among authors. At first, a series of powders characterisations of AISI 316 L stainless steel (below 25 μm) was adopted. The next step was to characterise the rheological behaviour of the feedstock using different rheological apparatus, so as to find the most appropriate equipment to the low-pressure powder injection molding process. The mass has to present a favourable rheological behaviour, which is low viscosity. The results of the physical characterisation were correlated among themselves and with the rheological characterisation. This was undertaken with the purpose of finding agreement among their values. Finally, the possibility of injection of water and gas atomised stainless steel coarse powders feedstock was studied. This presents as main advantage, the reduction of costs for the process. According to the literature, only powders with size below 25 μm are possible to be injected. Hence, starting from the physical characterisation of particles and rheological characterisation of the feedstock, the formulation of an appropriate mass was found for the coarse powders. These coarse powders were characterised by particles below 45 μm. In this case it was necessary to alter drastically the feedstock composition, using high amounts of wax, which lead to unstable rheological conditions. But, it was

  6. Tool path planning of hole-making operations in ejector plate of injection mould using modified shuffled frog leaping algorithm

    Directory of Open Access Journals (Sweden)

    Amol M. Dalavi

    2016-07-01

    Full Text Available Optimization of hole-making operations in manufacturing industry plays a vital role. Tool travel and tool switch planning are the two major issues in hole-making operations. Many industrial applications such as moulds, dies, engine block, automotive parts etc. requires machining of large number of holes. Large number of machining operations like drilling, enlargement or tapping/reaming are required to achieve the final size of individual hole, which gives rise to number of possible sequences to complete hole-making operations on the part depending upon the location of hole and tool sequence to be followed. It is necessary to find the optimal sequence of operations which minimizes the total processing cost of hole-making operations. In this work, therefore an attempt is made to reduce the total processing cost of hole-making operations by applying relatively new optimization algorithms known as shuffled frog leaping algorithm and proposed modified shuffled frog leaping algorithm for the determination of optimal sequence of hole-making operations. An industrial application example of ejector plate of injection mould is considered in this work to demonstrate the proposed approach. The obtained results by the shuffled frog leaping algorithm and proposed modified shuffled frog leaping algorithm are compared with each other. It is seen from the obtained results that the results of proposed modified shuffled frog leaping algorithm are superior to those obtained using shuffled frog leaping algorithm.

  7. Investigation of the powder loading of gas-atomized Ti6Al4V powder using an ‘in-house’ binder for metal injection moulding

    CSIR Research Space (South Africa)

    Seerane, MN

    2013-10-01

    Full Text Available Powder loading is one of the most critical factors in metal injection moulding (MIM) technology. It largely determines the success or failure of the subsequent MIM processes. A gas-atomized Ti6Al4V powder was investigated to determine an optimum...

  8. Rheological parameters used for deliberate deformation of a flexible mould after casting

    NARCIS (Netherlands)

    Grunewald, S.; Schipper, H.R.; Raghunath, P.

    2013-01-01

    This paper describes how curved precast concrete elements can be manufactured in an open and reusable flexible mould. The proposed method reduces formwork costs of architectural freeform elements in concrete. First, the method is described briefly, then a series of tests are discussed, demonstrating

  9. Design of conformal cooling for plastic injection moulding by heat transfer simulation

    Directory of Open Access Journals (Sweden)

    Sabrina Marques

    2015-12-01

    Full Text Available The cooling channels of a mold for plastic injection have to be as close as possible to the part geometry in order to ensure fast and homogeneous cooling. However, conventional methods to manufacture cooling channels (drilling can only produce linear holes. Selective laser melting (SLM is an additive manufacturing technique capable to manufacture complex cooling channels (known as conformal cooling. Nevertheless, because of the high costs of SLM the benefits of conformal collings are still not clear. The current work investigates two designs of conformal coolings: i parallel circuit; ii serial circuit. Both coolings are evaluated against to traditional cooling circuits (linear channels by CAE simulation to produce parts of polypropylene. The results show that if the conformal cooling is not properly designed it cannot provide reasonable results. The deformation of the product can be reduced significantly after injection but the cycle time reduced not more than 6%.

  10. A MILP for multi-machine injection moulding sequencing in the scope of C2NET Project

    Directory of Open Access Journals (Sweden)

    Beatriz Andrés

    2018-01-01

    Full Text Available The goal of C2NET European H2020 Funded Project is the creation of cloud-enabled tools for supporting the SMEs supply network optimization of manufacturing and logistic assets based on collaborative demand, production and delivery plans. In the scope of C2NET Project, and particularly in the Optimisation module (C2NET OPT, this paper proposes a novel holistic mixed integer linear programing (MILP model to optimise the injection sequencing in a multi-machine case. The results of the MILP will support the production planner decision-making process in the calculation of (i moulds setup in certain machines, and (ii the amount of products to produce in order to minimise the setup, inventory, and backorders costs. The designed MILP takes part of the algorithms repository created in C2NET European Funded Project to solve realistic industry planning problems. The MILP is verified in realistic data considering three data sets with different sizes, in order to test it’s the computation efficiency.

  11. PEM fuel cells with injection moulded bipolar plates of highly filled graphite compounds; PEM-Brennstoffzellen mit spritzgegossenen Bipolarplatten aus hochgefuelltem Graphit-Compound

    Energy Technology Data Exchange (ETDEWEB)

    Kreuz, Can

    2008-04-11

    This work concerns with the injection moulding of highly filled graphite compounds to bipolar plates for PEM fuel cells in a power output range between 100 - 500 Watts. A particular focus is laid on the combination of the three multidisciplinary scopes like material development, production technology and component development / design. The results of the work are specified by the process-oriented characterisation of the developed and manufactured bipolar plates as well as their application in a functioning fuel cell. (orig.)

  12. Improvement of replication fidelity in injection moulding of nano structures using an induction heating system

    DEFF Research Database (Denmark)

    Menotti, Stefano; Hansen, Hans Nørgaard; Bissacco, Giuliano

    2014-01-01

    In today’s industry, applications involving surface pattering with sub-μm scale structures have shown a high interest. The replication of these structures by injection molding leads to special requirements for the mold in order to ensure proper replication and an acceptable cycle time. A tool ins...... quantitatively characterized by atomic force microscopy comparing the measurement in the nickel insert with the corresponding polymer nano-features. The experimental results show that the use of the induction heating system is an efficient way to improve the pattern replication....

  13. Chopped basalt fibres: A new perspective in reinforcing poly(lactic acid to produce injection moulded engineering composites from renewable and natural resources

    Directory of Open Access Journals (Sweden)

    P. Tamas

    2013-02-01

    Full Text Available This paper focuses on the reinforcing of Poly(lactic acid with chopped basalt fibres by using silane treated and untreated basalt fibres. Composite materials with 5–10–15–20–30–40 wt% basalt fibre contents were prepared from silane sized basalt fibres using extrusion, and injection moulding, while composites with 5–10–15 wt% basalt fibre contents were also prepared by using untreated basalt fibres as control. The properties of the injection moulded composites were extensively examined by using quasi-static (tensile, three-point bending and dynamic mechanical tests (notched and unnotched Charpy impact tests, dynamic mechanical analysis (DMA, differential scanning calorimetry (DSC, heat deflection temperature (HDT analysis, dimensional stability test, as well as melt flow index (MFI analysis and scanning electron microscopic (SEM observations. It was found that silane treated chopped basalt fibres are much more effective in reinforcing Poly(lactic acid than natural fibres; although basalt fibres are not biodegradable but they are still considered as natural (can be found in nature in the form of volcanic rocks and biologically inert. It is demonstrated in this paper that by using basalt fibre reinforcement, a renewable and natural resource based composite can be produced by injection moulding with excellent mechanical properties suitable even for engineering applications. Finally it was shown that by using adequate drying of the materials, composites with higher mechanical properties can be achieved compared to literature data.

  14. Assembly injection moulding joins metal and thermoplastics; Montagespritzgiessen verbindet Metall und Thermoplast

    Energy Technology Data Exchange (ETDEWEB)

    Drummer, Dietmar; Meister, Steve [Erlangen-Nuernberg Univ., Erlangen (Germany). Lehrstuhl fuer Kunststofftechnik; Reichart, Marc [HBW Gubesch Kunststoff Engineering GmbH, Wilhelmsdorf (Germany)

    2010-03-08

    Automotive safety restraint system components increasingly use flexible styrenic and olefinic TPEs. With continued evolution in automotive interior design and performance requirements, demands on material technology are concomitantly rising. A growing trend towards molded in color solutions with low gloss aesthetics require TPE materials with ery low gloss, improved scratch resistance, and low temperature ductility. Innovations utilizing Teknor Apex's compounding technology have enabled the development of low gloss styrenic elastomers for airbag door applications that provide an optimized combination of low temperature performance, surface aesthetics (low gloss and improved scratch resistance), and ease of processing. This paper highlights the salient features of these new compounds and the effect of injection molding condition on the gloss at the surface of the cover.

  15. Tribological evaluation for experimental design Al_2O_3 obtained via low pressure injection moulding (LPIM)

    International Nuclear Information System (INIS)

    Dotta, A.L.B.; Costa, C.A.; Farias, M.C.M.; Cunha, M.A da

    2016-01-01

    This work represents the tribological study of Al_2O_3 obtained by LPIM using the experimental design technique to evaluate the interaction of the tribological parameters with the friction and wear. The LPIM process was performed at 90 °C for 24 h. The average friction coefficient for the factorial experimental design varied significantly with the load and the speed when Al_2O_3 was tested with the steel counter body. In general, the wear coefficient was lower for the tribological pair Al_2O_3-steel, in which occurred the formation of an iron oxide tribofilm on the surface. As for the Al_2O_3-Al_2O_3 pair, an intergranular fracture of the surface occurred, in addition to the presence of material adhered on the tracks. (author)

  16. Effects of holding pressure and process temperatures on the mechanical properties of moulded metallic parts

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Esteves, N.M.

    2013-01-01

    Metal injection moulding is gaining more and more importance over the time and needs more research to be done to understand the sensitivity of process to different process parameters. The current paper makes an attempt to better understand the effects of holding pressure and process temperatures...... on the moulded metallic parts. Stainless steel 316L is used in the investigation to produce the specimen by metal injection moulding (MIM) and multiple analyses were carried out on samples produced with different combinations of holding pressure, mould temperature and melt temperature. Finally, the parts were...... characterized to investigate mechanical properties like density, ultimate tensile strength, shrinkage etc. The results are discussed in the paper. The main conclusion from this study is unlike plastic moulding, the tensile properties of MIM parts doesn’t vary based on the flow direction of the melt, and tensile...

  17. A microfluidic control system with re-usable micropump/valve actuator and injection moulded disposable polymer lab-on-a-slide

    DEFF Research Database (Denmark)

    Bu, Minqiang; Perch-Nielsen, Ivan R.; Yi, Sun

    2011-01-01

    A microfluidic control system consisting of micropump/valves with a re-usable pneumatic actuator and a disposable polymer lab-on-a-slide is presented. The lab-on-a-slide was fabricated using low cost methods, such as injection moulding of TOPAS® cyclic olefin copolymer (COC) slide, lamination...... of different layers of polymer, and ultrasonic welding of TOPAS® lid to the slide. The re-usable pneumatic actuator not only simplifies the design of the lab-on-a-slide and reduces the fabrication cost, but also reduces the possibility of cross contamination during replacement of the disposable lab...

  18. Worldwide Injection Technique Questionnaire Study: Population Parameters and Injection Practices.

    Science.gov (United States)

    Frid, Anders H; Hirsch, Laurence J; Menchior, Astrid R; Morel, Didier R; Strauss, Kenneth W

    2016-09-01

    From February 1, 2014, through June 30, 2015, 13,289 insulin-injecting patients from 423 centers in 42 countries took part in one of the largest surveys ever performed in diabetes. The goal was to assess patient characteristics, as well as historical and practical aspects of their injection technique. Results show that 4- and 8-mm needle lengths are each used by nearly 30% of patients and 5- and 6-mm needles each by approximately 20%. Higher consumption of insulin (as measured by total daily dose) is associated with having lipohypertrophy (LH), injecting into LH, leakage from the injection site, and failing to reconstitute cloudy insulin. Glycated hemoglobin values are, on average, 0.5% higher in patients with LH and are significantly higher with incorrect rotation of sites and with needle reuse. Glycated hemoglobin values are lower in patients who distribute their injections over larger injection areas and whose sites are inspected routinely. The frequencies of unexpected hypoglycemia and glucose variability are significantly higher in those with LH, those injecting into LH, those who incorrectly rotate sites, and those who reuse needles. Needles associated with diabetes treatment are the most commonly used medical sharps in the world. However, correct disposal of sharps after use is critically suboptimal. Many used sharps end up in public trash and constitute a major accidental needlestick risk. Use of these data should stimulate renewed interest in and commitment to optimizing injection practices in patients with diabetes. Copyright © 2016 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  19. Liquid carry-over in an injection moulded all-polymer chip system for immiscible phase magnetic bead-based solid-phase extraction

    Energy Technology Data Exchange (ETDEWEB)

    Kistrup, Kasper, E-mail: kkis@nanotech.dtu.dk [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby (Denmark); Skotte Sørensen, Karen, E-mail: karen@nanotech.dtu.dk [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby (Denmark); Center for Integrated Point of Care Technologies (CiPoC), DELTA, Venlighedsvej 4, DK-2870 Hørsholm (Denmark); Wolff, Anders, E-mail: anders.wolff@nanotech.dtu.dk [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby (Denmark); Fougt Hansen, Mikkel, E-mail: mikkel.hansen@nanotech.dtu.dk [Department of Micro- and Nanotechnology, Technical University of Denmark, DTU Nanotech, Building 345 East, DK-2800 Kongens Lyngby (Denmark)

    2015-04-15

    We present an all-polymer, single-use microfluidic chip system produced by injection moulding and bonded by ultrasonic welding. Both techniques are compatible with low-cost industrial mass-production. The chip is produced for magnetic bead-based solid-phase extraction facilitated by immiscible phase filtration and features passive liquid filling and magnetic bead manipulation using an external magnet. In this work, we determine the system compatibility with various surfactants. Moreover, we quantify the volume of liquid co-transported with magnetic bead clusters from Milli-Q water or a lysis-binding buffer for nucleic acid extraction (0.1 (v/v)% Triton X-100 in 5 M guanidine hydrochloride). A linear relationship was found between the liquid carry-over and mass of magnetic beads used. Interestingly, similar average carry-overs of 1.74(8) nL/µg and 1.72(14) nL/µg were found for Milli-Q water and lysis-binding buffer, respectively. - Highlights: • We present an all-polymer mass producible passive filled microfluidic chip system. • Rapid system fabrication is obtained by injection moulding and ultrasonic welding. • The system is made for single-use nucleic acid extraction using magnetic beads. • We systematically map compatibility of the chip system with various surfactants. • We quantify the volume carry-over of magnetic beads in water and 0.1% triton-X solution.

  20. Liquid carry-over in an injection moulded all-polymer chip system for immiscible phase magnetic bead-based solid-phase extraction

    International Nuclear Information System (INIS)

    Kistrup, Kasper; Skotte Sørensen, Karen; Wolff, Anders; Fougt Hansen, Mikkel

    2015-01-01

    We present an all-polymer, single-use microfluidic chip system produced by injection moulding and bonded by ultrasonic welding. Both techniques are compatible with low-cost industrial mass-production. The chip is produced for magnetic bead-based solid-phase extraction facilitated by immiscible phase filtration and features passive liquid filling and magnetic bead manipulation using an external magnet. In this work, we determine the system compatibility with various surfactants. Moreover, we quantify the volume of liquid co-transported with magnetic bead clusters from Milli-Q water or a lysis-binding buffer for nucleic acid extraction (0.1 (v/v)% Triton X-100 in 5 M guanidine hydrochloride). A linear relationship was found between the liquid carry-over and mass of magnetic beads used. Interestingly, similar average carry-overs of 1.74(8) nL/µg and 1.72(14) nL/µg were found for Milli-Q water and lysis-binding buffer, respectively. - Highlights: • We present an all-polymer mass producible passive filled microfluidic chip system. • Rapid system fabrication is obtained by injection moulding and ultrasonic welding. • The system is made for single-use nucleic acid extraction using magnetic beads. • We systematically map compatibility of the chip system with various surfactants. • We quantify the volume carry-over of magnetic beads in water and 0.1% triton-X solution

  1. Process Factors Influence on Cavity Pressure Behavior in Microinjection Moulding

    DEFF Research Database (Denmark)

    Griffiths, C. A.; Dimov, S. S.; Scholz, S.

    2011-01-01

    about the filling behavior of different polymer melts. In this paper, a pressure sensor mounted inside a tool cavity was employed to analyse maximum cavity pressure, pressure increase rate during filling and pressure work. The influence of four mu IM parameters, melt temperature, mould temperature......Process monitoring of microinjection moulding (mu IM) is of crucial importance when analysing the effect of different parameter settings on the process and then in assessing its quality. Quality factors related to cavity pressure can provide valuable information about the process dynamics and also......, injection speed, and packing pressure on these three pressure-related process parameters was investigated. A design of experiment study was conducted by moulding a test part, a microfluidic component, in three different polymer materials, PP, ABS, and PC. The results show a similar process behavior for all...

  2. Moulding of Sub-micrometer Surface Structures

    DEFF Research Database (Denmark)

    Pranov, Henrik; Rasmussen, Henrik K.; Larsen, Niels Bent

    2006-01-01

    The experiments strongly suggest that the possibility to injection mould sub-micrometer surface structures in polymers mainly relates to the forces originating from the adhesive energy between polymer and shim.......The experiments strongly suggest that the possibility to injection mould sub-micrometer surface structures in polymers mainly relates to the forces originating from the adhesive energy between polymer and shim....

  3. Liquid carry-over in an injection moulded all-polymer chip system for immiscible phase magnetic bead-based solid-phase extraction

    DEFF Research Database (Denmark)

    Kistrup, Kasper; Sørensen, Karen Skotte; Wolff, Anders

    2014-01-01

    We present an all-polymer, single-use microfluidic chip system produced by injection moulding and bonded by ultrasonic welding. Both techniques are compatible with low-cost industrial mass-production. The chip is produced for magnetic bead-based solid-phase extraction facilitated by immiscible......-binding buffer for nucleic acid extraction (0.1 (v/v)% Triton X-100 in 5 M guanidine hydrochloride). A linear relationship was found between the liquid carry-over and mass of magnetic beads used. Interestingly, similar average carry-overs of 1.74(8) nL/µg and 1.72(14) nL/µg were found for Milli-Q water and lysis...

  4. Micromilling of hardened tool steel for mould making applications

    DEFF Research Database (Denmark)

    Bissacco, Giuliano; Hansen, Hans Nørgaard; De Chiffre, Leonardo

    2005-01-01

    geometries as those characterizing injection moulding moulds. The realization of the micromilling process in connection with hardened tool steel as workpiece material is particularly challenging. The low strength of the miniaturized end mills implies reduction and accurate control of the chip load which...... wear. This paper presents the micromilling process applied to the manufacturing of micro injection moulding moulds in hardened tool steel, presenting experimental evidence and possible solutions to the above-mentioned issues....

  5. Fabrication of nuclear fuel by powder injection moulding: Study of the binders systems and the de-binding of feedstock containing actinide powder

    International Nuclear Information System (INIS)

    Bricout, J.

    2012-01-01

    Powder Injection Moulding (PIM) is identified as an innovative process for the nuclear fuel fabrication. Technological breakthrough compared to the current process of powder metallurgy, the impact of actinide powder's specificities on the different steps of PIM is performed. Alumina powders simulating actinide powder have been implemented with a reference binders system. Thermal and rheological studies show the injectability and the de-binding of feedstocks with adequate solid loading (≥50 %vol), thanks to the de-agglomeration during the mixing step, which allow to obtain net shape fuel pellet. Specific surface area of powders, acting as a key role in behaviour's feedstocks, has been integrated in analysis models of viscosity prediction according to the shear rate. Also conducted studies on uranium oxide powder show that the selected binders systems, which have a compatible rheological behaviour with PIM process, impact the de-agglomeration of powder and final microstructure of the fuel pellet, consistent with the results obtained on alumina powders. Independent behaviour of binders and uranium oxide powder, showing no adverse chemical reaction against the PIM process, show a residual mass of carbon of about 150 ppm after sintering. Binders system using polystyrene, resistant to radiolysis phenomena and loadable more than 50 %(vol) of actinide powder, shows the promising potential of PIM process for the fuel fabrication. (author) [fr

  6. Improving the Wear Resistance of Moulds for the Injection of Glass Fibre–Reinforced Plastics Using PVD Coatings: A Comparative Study

    Directory of Open Access Journals (Sweden)

    Francisco Silva

    2017-02-01

    Full Text Available It is well known that injection of glass fibre–reinforced plastics (GFRP causes abrasive wear in moulds’ cavities and runners. Physical vapour deposition (PVD coatings are intensively used to improve the wear resistance of different tools, also being one of the most promising ways to increase the moulds’ lifespan, mainly when used with plastics strongly reinforced with glass fibres. This work compares four different thin, hard coatings obtained using the PVD magnetron sputtering process: TiAlN, TiAlSiN, CrN/TiAlCrSiN and CrN/CrCN/DLC. The first two are monolayer coatings while the last ones are nanostructured and consist of multilayer systems. In order to carry out the corresponding tribological characterization, two different approaches were selected: A laboratorial method, using micro-abrasion wear tests based on a ball-cratering configuration, and an industrial mode, analysing the wear resistance of the coated samples when inserted in a plastic injection mould. As expected, the wear phenomena are not equivalent and the results between micro-abrasion and industrial tests are not similar due to the different means used to promote the abrasion. The best wear resistance performance in the laboratorial wear tests was attained by the TiAlN monolayer coating while the best performance in the industrial wear tests was obtained by the CrN/TiAlCrSiN nanostructured multilayer coating.

  7. Injection Molding Parameters Calculations by Using Visual Basic (VB) Programming

    Science.gov (United States)

    Tony, B. Jain A. R.; Karthikeyen, S.; Alex, B. Jeslin A. R.; Hasan, Z. Jahid Ali

    2018-03-01

    Now a day’s manufacturing industry plays a vital role in production sectors. To fabricate a component lot of design calculation has to be done. There is a chance of human errors occurs during design calculations. The aim of this project is to create a special module using visual basic (VB) programming to calculate injection molding parameters to avoid human errors. To create an injection mold for a spur gear component the following parameters have to be calculated such as Cooling Capacity, Cooling Channel Diameter, and Cooling Channel Length, Runner Length and Runner Diameter, Gate Diameter and Gate Pressure. To calculate the above injection molding parameters a separate module has been created using Visual Basic (VB) Programming to reduce the human errors. The outcome of the module dimensions is the injection molding components such as mold cavity and core design, ejector plate design.

  8. Liquid carry-over in an injection moulded all-polymer chip system for immiscible phase magnetic bead-based solid-phase extraction

    Science.gov (United States)

    Kistrup, Kasper; Skotte Sørensen, Karen; Wolff, Anders; Fougt Hansen, Mikkel

    2015-04-01

    We present an all-polymer, single-use microfluidic chip system produced by injection moulding and bonded by ultrasonic welding. Both techniques are compatible with low-cost industrial mass-production. The chip is produced for magnetic bead-based solid-phase extraction facilitated by immiscible phase filtration and features passive liquid filling and magnetic bead manipulation using an external magnet. In this work, we determine the system compatibility with various surfactants. Moreover, we quantify the volume of liquid co-transported with magnetic bead clusters from Milli-Q water or a lysis-binding buffer for nucleic acid extraction (0.1 (v/v)% Triton X-100 in 5 M guanidine hydrochloride). A linear relationship was found between the liquid carry-over and mass of magnetic beads used. Interestingly, similar average carry-overs of 1.74(8) nL/μg and 1.72(14) nL/μg were found for Milli-Q water and lysis-binding buffer, respectively.

  9. Influence of 1D and 2D Carbon Fillers and Their Functionalisation on Crystallisation and Thermomechanical Properties of Injection Moulded Nylon 6,6 Nanocomposites

    Directory of Open Access Journals (Sweden)

    Fabiola Navarro-Pardo

    2014-01-01

    Full Text Available Carbon nanotubes (CNTs and graphene were used as reinforcing fillers in nylon 6,6 in order to obtain nanocomposites by using an injection moulding process. The two differently structured nanofillers were used in their pristine or reduced form, after oxidation treatment and after amino functionalisation. Three low nanofiller contents were employed. Crystallisation behaviour and perfection of nylon 6,6 crystals were determined by differential scanning calorimetry and wide angle X-ray diffraction, respectively. Crystallinity was slightly enhanced in most samples as the content of the nanofillers was increased. The dimensionality of the materials was found to provide different interfaces and therefore different features in the nylon 6,6 crystal growth resulting in improved crystal perfection. Dynamical, mechanical analysis showed the maximum increases provided by the two nanostructures correspond to the addition of 0.1 wt.% amino functionalised CNTs, enhancing in 30% the storage modulus and the incorporation of 0.5 wt.% of graphene oxide caused an increase of 44% in this property. The latter also provided better thermal stability when compared to pure nylon 6,6 under inert conditions. The superior properties of graphene nanocomposites were attributed to the larger surface area of the two-dimensional graphene compared to the one-dimensional CNTs.

  10. Mould Design and Material selection for Film Insert Moulding of Direct Methanol Fuel Cell Packaging

    DEFF Research Database (Denmark)

    Wöhner, Timo; Senkbeil, S.; Olesen, T. L.

    2015-01-01

    This paper presents the mould design for an injection moulding (IM) process for the production of a methanol container for the use in small, passive Direct Methanol Fuel Cell (DMFC) systems, which are intended to be used in behind-the-ear hearing aid systems. One of the crucial properties...... for the production of containers with different venting area and location of the venting holes and the use of different membrane thicknesses by using the same mould. Mould design and material selection are presented....

  11. Influence of binder system and temperature on rheological properties of water atomized 316L powder injection moulding feedstocks

    Directory of Open Access Journals (Sweden)

    Uğur GÖKMEN

    2016-02-01

    Full Text Available In order to obtain a proper powder injection molding the rheological behavior of feedstocks should be known. To determine the binder effect on the rheological behavior of 316L stainless steel powders feedstock two different feedstock were prepared. In the current experiments water atomized 316L stainless steel powders (-20 µm were used. Two types of binders, one of which is mainly paraffin wax can be dissolved in heptane and the other Polietilenglikol (PEG based and can be dissolved in water, were used. Polypropylene was used as binder and steric acid was used as lubricant for both binder systems as skeleton binder. Dry binder system were mixed for 30 min in a three dimensional Turbola. Capillary rheometer was used to characterize the rheological properties of feed stocks at 150-200 °C and a pressures of 0.165-2.069 MPa. Powder loading capacity of PEG and PW based feed stocks were found to be %55 and %61 respectively. The lowest viscosity of PEG and PW based feed stocks were found to be 304.707 Pa.s and 48.857 Pa.s respectively.Keywords: PIM, Binder, Rheological properties

  12. Packing parameters effect on injection molding of polypropylene nanostructured surfaces

    DEFF Research Database (Denmark)

    Calaon, Matteo; Tosello, Guido; Hansen, Hans Nørgaard

    2012-01-01

    having a diameter of 500 nm was employed. The tool insert surface was produced using chemical-based-batch techniques such aluminum anodization and nickel electroplating. During the injection molding process, polypropylene (PP) was employed as material and packing phase parameters (packing time, packing...

  13. Local measurement of transport parameters for laser injected trace impurities

    Energy Technology Data Exchange (ETDEWEB)

    Giannella, R; Lauro-Taroni, L [Commission of the European Communities, Abingdon (United Kingdom). JET Joint Undertaking

    1994-07-01

    A procedure has been developed that determines local measurements of transport parameters`s profiles for injected impurities. The measured profiles extend from the plasma centre up to a certain radial position (usually {rho} = 0.6-0.7). In the outer region of the plasma the procedure supplies ``most suitable extensions`` up to the plasma edge of the measured transport profiles. The procedure intrinsically assures consistency and excellent agreement between the simulated and experimental data of local broad band soft X-ray emissivity and intensities of individual emission lines from different ion states of the injected impurities. 4 refs., 3 figs.

  14. Effects of fixed orthodontic treatment using conventional (two-piece) versus metal injection moulding brackets on hair nickel and chromium levels: a double-blind randomized clinical trial.

    Science.gov (United States)

    Khaneh Masjedi, Mashallah; Haghighat Jahromi, Nima; Niknam, Ozra; Hormozi, Elham; Rakhshan, Vahid

    2017-02-01

    Although nickel and chromium are known as allergen and cytotoxic orthodontic metals, very few and controversial studies have assessed the effect of orthodontic treatment on their systemic levels especially those reflected by their best biomarker of exposure, hair. Additionally, metal injection moulding (MIM) brackets are not studied, and there is no study on systemic ion changes following their usage. In this double-blind randomized clinical trial, scalp hair samples of 24 female and 22 male fixed orthodontic patients [as two groups of conventional (two-piece) versus MIM brackets, n = 23×2] were collected before treatment and 6 months later. Randomization was carried out using a computer-generated random number table. The patients, laboratory expert, and author responsible for analyses were blinded of the bracket allocations. Hair nickel and chromium levels were measured using atomic absorption spectrophotometry. The effects of treatment, bracket types, gender, and age on hair ions were analysed statistically (α = 0.05, β ≤ 0.02). In both groups combined (n = 46), nickel increased from 0.1600±0.0890 µg/g dry hair mass (pre-treatment) to 0.3199±0.1706 (6th month). Chromium increased from 0.1657±0.0884 to 0.3066±0.1362 µg/g. Both of these increases were significant (paired t-test, P = 0.0000). Bracket types, age, and gender had no significant influence on ion levels (P > 0.05). ANCOVA indicated different patterns of chromium increases in different genders (P = 0.033) and ages (P = 0.056). Sample size determination should have accounted for the grouping as well. Hair nickel and chromium levels might increase about 185-200% after 6 months. They might not be affected by bracket types. Gender and age might not influence the baseline or 6th-month levels of both metals. Gender might however interact with orthodontic treatment, only in the case of chromium. The research is registered offline (thesis) and online (IR.AJUMS.REC.1394.516). The protocol was pre

  15. Best practice strategies for validation of micro moulding process simulation

    DEFF Research Database (Denmark)

    Costa, Franco; Tosello, Guido; Whiteside, Ben

    2009-01-01

    are the optimization of the moulding process and of the tool using simulation techniques. Therefore, in polymer micro manufacturing technology, software simulation tools adapted from conventional injection moulding can provide useful assistance for the optimization of moulding tools, mould inserts, micro component...... are discussed. Recommendations regarding sampling rate, meshing quality, filling analysis methods (micro short shots, flow visualization) and machine geometry modelling are given on the basis of the comparison between simulated and experimental results within the two considered study cases.......Simulation programs in polymer micro replication technology are used for the same reasons as in conventional injection moulding. To avoid the risks of costly re-engineering, the moulding process is simulated before starting the actual manufacturing process. Important economic factors...

  16. Developments in the implantation of moulding tools

    International Nuclear Information System (INIS)

    Dearnaley, G.; Delves, B.G.

    1983-01-01

    The process of surface hardening by the ion implantation of nitrogen has proved to be remarkably effective for the treatment of moulds, and indeed the whole range of screws, nozzles, sprue bushes, etc., as well as dies for injection moulding or extrusion of filled plastics. Implantation equipment, based upon our designs, is now available commercially. Corrosion and pitting of moulds can be reduced by a new ionic treatment known as ion beam mixing. A thin coating of protective material, such as chromium on silicon, is bombarded with ions so as to mix or key it to the mould surface. Alternatively, hydrocarbon vapour can be cracked on to the metal surface to form a tenacious and protective carbon film. Industrial applications for this novel process are now being sought. (author)

  17. Precision moulding of polymer micro components

    DEFF Research Database (Denmark)

    Tosello, Guido

    2008-01-01

    The present research work contains a study concerning polymer micro components manufacturing by means of the micro injection moulding (µIM) process. The overall process chain was considered and investigated during the project, including part design and simulation, tooling, process analysis, part...... optimization, quality control, multi-material solutions. A series of experimental investigations were carried out on the influence of the main µIM process factors on the polymer melt flow within micro cavities. These investigations were conducted on a conventional injection moulding machine adapted...... to the production of micro polymer components, as well as on a micro injection moulding machine. A new approach based on coordinate optical measurement of flow markers was developed during the project for the characterization of the melt flow. In-line pressure measurements were also performed to characterize...

  18. Relationship between sperm parameters and intracytoplasmic sperm injection outcome

    Directory of Open Access Journals (Sweden)

    Shahla Chaichian

    2015-12-01

    Full Text Available Objectives: With the adventure of intracytoplasmic sperm injection (ICSI technique, great progresses have developed in the treatment of infertility. Concentration on the properties of male’s gamete has been encouraged by the increasing concerns about the causes of ICSI failure. We hence conducted this study to investigate the probable association of sperm parameters with ISCI outcome. Methods: A total of 523 couples referred to Isfahan Fertility and Sterility Center from January 2007 to June 2008 for ICSI. Semen analysis was performed before ICSI procedure according to the WHO criteria. Patients were assigned into successful ICSI (case and failed ICSI (control groups. Sperm parameters were then compared between the 2 groups. Results: One hundred and six patients (20% had successful ICSI results (case group compared with 417 couples (80% with undesirable ICSI outcomes (control group. Among evaluated factors, sperm agglutination (p = 0.007, sperm concentration (p = 0.043, leukocytospermia (p = 0.026 and head abnormality of sperm (p = 0.019 showed statistically significant differences between two groups with differing ICSI results. None of the other semen parameters revealed significant differences between these two groups. Conclusion: Our study showed that some sperm parameters are associated with desirable ICSI outcome. However, it is unclear whether these associations are causal.

  19. Physical characterisation of particles and rheological of a heterogeneous system used in low-pressure injection moulding; Caracterizacao fisica de particulas e reologica de um sistema heterogeneo utilizado em moldagem de pos por injecao a baixa pressao

    Energy Technology Data Exchange (ETDEWEB)

    Zampieron, Joao Vicente

    2002-07-01

    The powder injection moulding process is a recent technology, which offers as advantages a high production of complex geometry metal parts, with low cost, where secondary operations of machinery are unnecessary. The main of this thesis was centered on a coarse powders feedstock injection. The process begins with the composition of the mass, that is the combination of metal powders with organic binders. The following steps succeed injection in moulds, debinding, sintering and, if necessary, cleaning. For the formulation of the feedstock it is indispensable the characterisation of the powders. This is little mentioned in the open literature and brings up controversy among authors. At first, a series of powders characterisations of AISI 316 L stainless steel (below 25 {mu}m) was adopted. The next step was to characterise the rheological behaviour of the feedstock using different rheological apparatus, so as to find the most appropriate equipment to the low-pressure powder injection molding process. The mass has to present a favourable rheological behaviour, which is low viscosity. The results of the physical characterisation were correlated among themselves and with the rheological characterisation. This was undertaken with the purpose of finding agreement among their values. Finally, the possibility of injection of water and gas atomised stainless steel coarse powders feedstock was studied. This presents as main advantage, the reduction of costs for the process. According to the literature, only powders with size below 25 {mu}m are possible to be injected. Hence, starting from the physical characterisation of particles and rheological characterisation of the feedstock, the formulation of an appropriate mass was found for the coarse powders. These coarse powders were characterised by particles below 45 {mu}m. In this case it was necessary to alter drastically the feedstock composition, using high amounts of wax, which lead to unstable rheological conditions. But, it

  20. Investigation of the pressure generated in the mould cavity during polyurethane integral skin foam moulding

    Directory of Open Access Journals (Sweden)

    2008-07-01

    Full Text Available An industrial scale measuring system was set up to investigate the pressure arising in the mould cavity during polyurethane integral skin foaming. The system is able to measure the pressure arising in the mould cavity and the pressure distribution using a piezoresistive pressure sensor. The pressure distribution was measured at 18 points along the mould surface at constant production parameters. Then six production parameters, which affect the pressure, were investigated in detail with the Taguchi method of experimental design. The results of the design were processed by ANOVA (analysis of variance. Three major influencing parameters were estimated by regression analysis. Finally an equation was developed to give a good estimation to the pressure arising in the mould cavity.

  1. Transcription of Small Surface Structures in Injection Molding - an Experimental Study

    DEFF Research Database (Denmark)

    Arlø, Uffe Rolf; Kjær, Erik Michael

    2001-01-01

    The ability to replicate the surface roughness from mold wall to the plastic part in injection moldning has many functional and cosmetic important implications from medical use to designer products. Generally the understanding of surface transcription i.e the the replication of the surface...... structure from the mould to plastic part, also relates to micro injection moulding and moulding of parts with specific micro structures on the surface such as optical parts. The present study concerns transcription of surface roughness as a function of process parameters. The study is carried out...

  2. Modelling the effect of injection pressure on heat release parameters and nitrogen oxides in direct injection diesel engines

    Directory of Open Access Journals (Sweden)

    Yüksek Levent

    2014-01-01

    Full Text Available Investigation and modelling the effect of injection pressure on heat release parameters and engine-out nitrogen oxides are the main aim of this study. A zero-dimensional and multi-zone cylinder model was developed for estimation of the effect of injection pressure rise on performance parameters of diesel engine. Double-Wiebe rate of heat release global model was used to describe fuel combustion. extended Zeldovich mechanism and partial equilibrium approach were used for modelling the formation of nitrogen oxides. Single cylinder, high pressure direct injection, electronically controlled, research engine bench was used for model calibration. 1000 and 1200 bars of fuel injection pressure were investigated while injection advance, injected fuel quantity and engine speed kept constant. The ignition delay of injected fuel reduced 0.4 crank angle with 1200 bars of injection pressure and similar effect observed in premixed combustion phase duration which reduced 0.2 crank angle. Rate of heat release of premixed combustion phase increased 1.75 % with 1200 bar injection pressure. Multi-zone cylinder model showed good agreement with experimental in-cylinder pressure data. Also it was seen that the NOx formation model greatly predicted the engine-out NOx emissions for both of the operation modes.

  3. Conditions for mould growth on typical interior surfaces

    DEFF Research Database (Denmark)

    Møller, Eva B.; Andersen, Birgitte; Rode, Carsten

    2017-01-01

    Prediction of the risk for mould growth is an important parameter for the analysis and design of the hygrothermal performance of building constructions. However, in practice the mould growth does not always follow the predicted behavior described by the mould growth models. This is often explained...... by uncertainty in the real conditions of exposure. In this study, laboratory experiments were designed to determine mould growth at controlled transient climate compared to growth at constant climate. The experiment included three building materials with four different surface treatments. The samples were...

  4. Bond strength investigation of two shot moulded polymer

    DEFF Research Database (Denmark)

    Islam, Mohammad Aminul

    This report on the project “Bond strength investigation of two shot moulded polymers” has been submitted for fulfilling the requirements for the course “Experimental Plastic Technology – 42234” at IPL-DTU. Two shot moulding is a classic manufacturing process to combine two different polymers...... in a single product and it is getting more and more importance day by day. One of the biggest challenges of two shot moulding is to achieve a reasonably good bonding between two polymers. The purpose of this project is to investigate the effects of different process, material and machine parameters...... on the bond strength of two shot moulded polymers. For the experiments two engineering polymers (PS and ABS) were used. After all the experimental work, several parameters were found which could effectively control the bond strength of two shot moulded polymers. This report also presents different aspects...

  5. Moulds in food spoilage

    DEFF Research Database (Denmark)

    Filtenborg, Ole; Frisvad, Jens Christian; Thrane, Ulf

    1996-01-01

    There is an increasing knowledge and understanding of the role played by moulds in food spoilage. Especially the discovery of mycotoxin production in foods has highligh-ted the importance of moulds in food quality. It is, however, only within the last 5-10 years that major progresses have been made...... the associated or critical funga and has been shown to consist of less than 10 species. In this paper the associated funga is described for the following foods: Citrus and pomaceous fruits, potato and yam tubers, onions, rye, wheat, rye bread, cheese and fermented sausages and whenever possible the selective...

  6. Injection Moulding Pilot Production: Performance Assessment of Tooling Process Chains Based on Tool Inserts Made from Brass and A 3d Printed Photopolymer

    DEFF Research Database (Denmark)

    Mischkot, Michael; Tosello, Guido; Nielsen, Daniel K. Y.

    2017-01-01

    -cavity mold. The inserts as well as selected injection molded parts were analyzed with an optical 3D micro-coordinate measuring machine. It was found that additive manufacturing technology can lead to a significantly more cost effective pilot production, both in terms of development time and investment. DLP...

  7. Diesel injector dynamic modelling and estimation of injection parameters from impact response part 2: prediction of injection parameters from monitored vibration

    OpenAIRE

    Gu, Fengshou; Ball, Andrew; Rao, K K

    1996-01-01

    Part 2 of this paper presents the experimental and analytical procedures used in the estimation of injection parameters from monitored vibration. The mechanical and flow‐induced sources of vibration in a fuel injector are detailed and the features of the resulting vibration response of the injector body are discussed. Experimental engine test and data acquisition procedures are described, and the use of an out‐of‐the‐engine test facility to confirm injection dependent vibration response is ou...

  8. Influence of the reclamation method of spent moulding sands on the possibility of creating favourable conditions for gases flow in a mould

    Directory of Open Access Journals (Sweden)

    Łucarz M.

    2017-03-01

    Full Text Available The results of investigations concerning the influence of the applied sand matrix (fresh sand, reclaim on the properties of moulding sands used for production of large dimensional castings (ingot moulds, ladles, are presented in the hereby paper. The performed investigations were aimed at determining the influence of various reclamation methods of spent moulding sands on the quality of the obtained reclaimed material. Moulding sands were prepared on the fresh quartz matrix as well as on sand matrices obtained after various reclamation methods. The selected moulding sand parameters were tested (strength, permeability, grindability, ignition losses, pH reactions. It can be stated, on the basis of the performed investigations, that the kind of the applied moulding sand matrix is of an essential meaning from the point of view of creating conditions minimising formation of large amounts of gases and their directional migration in a casting mould.

  9. Process control and product evaluation in micro molding using a screwless/two-plunger injection unit

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Dormann, B.

    2010-01-01

    A newly developed μ-injection molding machine equipped with a screwless/two-plunger injection unit has been employed to mould miniaturized dog-bone shaped specimens on polyoxymethylene and its process capability and robustness have been analyzed. The influence of process parameters on μ-injection......A newly developed μ-injection molding machine equipped with a screwless/two-plunger injection unit has been employed to mould miniaturized dog-bone shaped specimens on polyoxymethylene and its process capability and robustness have been analyzed. The influence of process parameters on μ......-injection molding was investigated using the Design of Experiments technique. Injection pressure and piston stroke speed as well as part weight and dimensions were considered as quality factors over a wide range of process parameters. Experimental results obtained under different processing conditions were...

  10. Best practice strategies for validation of micro moulding process simulation

    DEFF Research Database (Denmark)

    Costa, Franco; Tosello, Guido; Whiteside, Ben

    2009-01-01

    The use of simulation for injection moulding design is a powerful tool which can be used up-front to avoid costly tooling modifications and reduce the number of mould trials. However, the accuracy of the simulation results depends on many component technologies and information, some of which can...... be easily controlled or known by the simulation analyst and others which are not easily known. For this reason, experimental validation studies are an important tool for establishing best practice methodologies for use during analysis set up on all future design projects. During the validation studies......, detailed information about the moulding process is gathered and used to establish these methodologies. Whereas in routine design projects, these methodologies are then relied on to provide efficient but reliable working practices. Data analysis and simulations on preliminary micro-moulding experiments have...

  11. Parameter Optimization Of Natural Hydroxyapatite/SS316l Via Metal Injection Molding (MIM)

    Science.gov (United States)

    Mustafa, N.; Ibrahim1, M. H. I.; Amin, A. M.; Asmawi, R.

    2017-01-01

    Metal injection molding (MIM) are well known as a worldwide application of powder injection molding (PIM) where as applied the shaping concept and the beneficial of plastic injection molding but develops the applications to various high performance metals and alloys, plus metal matrix composites and ceramics. This study investigates the strength of green part by using stainless steel 316L/ Natural hydroxyapatite composite as a feedstock. Stainless steel 316L (SS316L) was mixed with Natural hydroxyapatite (NHAP) by adding 40 wt. % Low Density Polyethylene and 60 %wt. Palm Stearin as a binder system at 63 wt. % powder loading consist of 90 % wt. of SS316 L and 10 wt. % NHAP prepared thru critical powder volume percentage (CPVC). Taguchi method was functional as a tool in determining the optimum green strength for Metal Injection Molding (MIM) parameters. The green strength was optimized with 4 significant injection parameter such as Injection temperature (A), Mold temperature (B), Pressure (C) and Speed (D) were selected throughout screening process. An orthogonal array of L9 (3)4 was conducted. The optimum injection parameters for highest green strength were established at A1, B2, C0 and D1 and where as calculated based on Signal to Noise Ratio.

  12. Intelligent methods for the process parameter determination of plastic injection molding

    Science.gov (United States)

    Gao, Huang; Zhang, Yun; Zhou, Xundao; Li, Dequn

    2018-03-01

    Injection molding is one of the most widely used material processing methods in producing plastic products with complex geometries and high precision. The determination of process parameters is important in obtaining qualified products and maintaining product quality. This article reviews the recent studies and developments of the intelligent methods applied in the process parameter determination of injection molding. These intelligent methods are classified into three categories: Case-based reasoning methods, expert system- based methods, and data fitting and optimization methods. A framework of process parameter determination is proposed after comprehensive discussions. Finally, the conclusions and future research topics are discussed.

  13. Optimization of parameters for the inline-injection system at Brookhaven Accelerator Test Facility

    International Nuclear Information System (INIS)

    Parsa, Z.; Ko, S.K.

    1995-01-01

    We present some of our parameter optimization results utilizing code PARMLEA, for the ATF Inline-Injection System. The new solenoid-Gun-Solenoid -- Drift-Linac Scheme would improve the beam quality needed for FEL and other experiments at ATF as compared to the beam quality of the original design injection system. To optimize the gain in the beam quality we have considered various parameters including the accelerating field gradient on the photoathode, the Solenoid field strengths, separation between the gun and entrance to the linac as well as the (type size) initial charge distributions. The effect of the changes in the parameters on the beam emittance is also given

  14. Elasticity of Moulding Sands – a Method of Reducing Core Cracking

    Directory of Open Access Journals (Sweden)

    Dobosz St. M.

    2017-03-01

    Full Text Available This paper focuses on mechanical properties of self hardening moulding sands with furfuryl and alkyd binders. Elasticity as a new parameter of moulding sands is investigated. With the use of presented testing equipment, it is possible to determine force kinetics and deformation of moulding sand in real time. The need for this kind of study comes from the modern casting industry. New foundries can be characterized with high intensity of production which is correlated with high level of mechanization and automatization of foundry processes. The increasingly common use of manipulators in production of moulds and cores can lead to generation of new types of flaws, caused by breakage in moulds and cores which could occur during mould assembly. Hence it is required that moulds and cores have high resistance to those kinds of factors, attributing it with the phenomenon of elasticity. The article describes the theoretical basis of this property, presents methods of measuring and continues earlier research.

  15. Effect of injection molding parameters on nanofillers dispersion in masterbatch based PP-clay nanocomposites

    Directory of Open Access Journals (Sweden)

    J. Soulestin

    2012-03-01

    Full Text Available The effect of injection molding parameters (screw rotational speed, back pressure, injec-tion flow rate and holding pressure on the nanofiller dispersion of melt-mixed PP/clay nanocomposites was investigated. The nanocomposites containing 4 wt% clay were obtained by dilution of a PP/clay masterbatch into a PP matrix. The evaluation of the dispersion degree was obtained from dynamic rheological measurements. The storage modulus and complex viscosity exhibit significant dependence on the injection molding parameters. PP/clay nanocomposite molded using more severe injection parameters (high shear and long residence time displays the highest storage modulus and complex viscosity, which illustrates the improved dispersion of clay platelets. This better dispersion leads to better mechanical properties particularly higher Young modulus, tensile strength and unnotched impact strength. A Taguchi analysis was used to identify the influence of individual process parameters. The major individual parameter is the injection flow rate, whose increase improves nanoclay dispersion. The combination of high back pressure and high screw rotational speed is also necessary to optimize the dispersion of clay nanoplatelets.

  16. Effect of injection molding parameters on nanofillers dispersion in masterbatch based PP-clay nanocomposites

    OpenAIRE

    J. Soulestin; J. J. Rajesh; M. F. Lacrampe; P. Krawczak

    2012-01-01

    The effect of injection molding parameters (screw rotational speed, back pressure, injec-tion flow rate and holding pressure) on the nanofiller dispersion of melt-mixed PP/clay nanocomposites was investigated. The nanocomposites containing 4 wt% clay were obtained by dilution of a PP/clay masterbatch into a PP matrix. The evaluation of the dispersion degree was obtained from dynamic rheological measurements. The storage modulus and complex viscosity exhibit significant dependence on the injec...

  17. Warpage improvement on wheel caster by optimizing the process parameters using genetic algorithm (GA)

    Science.gov (United States)

    Safuan, N. S.; Fathullah, M.; Shayfull, Z.; Nasir, S. M.; Hazwan, M. H. M.

    2017-09-01

    In injection moulding process, the defects will always encountered and affected the final product shape and functionality. This study is concerning on minimizing warpage and optimizing the process parameter of injection moulding part. Apart from eliminating product wastes, this project also giving out best recommended parameters setting. This research studied on five parameters. The optimization showed that warpage have been improved 42.64% from 0.6524 mm to 0.30879 mm in Autodesk Moldflow Insight (AMI) simulation result and Genetic Algorithm (GA) respectively.

  18. Challenges of titanium metal injection moulding

    CSIR Research Space (South Africa)

    Benson, JM

    2007-11-01

    Full Text Available Titanium has fired the imagination of engineers and designers for decades by its ‘ideal’ combination of high strength, low density and good corrosion resistance. However, its application has unfortunately been limited to those niche markets where...

  19. Optimization of injection molding process parameters for a plastic cell phone housing component

    Science.gov (United States)

    Rajalingam, Sokkalingam; Vasant, Pandian; Khe, Cheng Seong; Merican, Zulkifli; Oo, Zeya

    2016-11-01

    To produce thin-walled plastic items, injection molding process is one of the most widely used application tools. However, to set optimal process parameters is difficult as it may cause to produce faulty items on injected mold like shrinkage. This study aims at to determine such an optimum injection molding process parameters which can reduce the fault of shrinkage on a plastic cell phone cover items. Currently used setting of machines process produced shrinkage and mis-specified length and with dimensions below the limit. Thus, for identification of optimum process parameters, maintaining closer targeted length and width setting magnitudes with minimal variations, more experiments are needed. The mold temperature, injection pressure and screw rotation speed are used as process parameters in this research. For optimal molding process parameters the Response Surface Methods (RSM) is applied. The major contributing factors influencing the responses were identified from analysis of variance (ANOVA) technique. Through verification runs it was found that the shrinkage defect can be minimized with the optimal setting found by RSM.

  20. Accurate characterisation of post moulding shrinkage of polymer parts

    DEFF Research Database (Denmark)

    Neves, L. C.; De Chiffre, L.; González-Madruga, D.

    2015-01-01

    The work deals with experimental determination of the shrinkage of polymer parts after injection moulding. A fixture for length measurements on 8 parts at the same time was designed and manufactured in Invar, mounted with 8 electronic gauges, and provided with 3 temperature sensors. The fixture w...

  1. Influence of Powder Injection Parameters in High-Pressure Cold Spray

    Science.gov (United States)

    Ozdemir, Ozan C.; Widener, Christian A.

    2017-10-01

    High-pressure cold spray systems are becoming widely accepted for use in the structural repair of surface defects of expensive machinery parts used in industrial and military equipment. The deposition quality of cold spray repairs is typically validated using coupon testing and through destructive analysis of mock-ups or first articles for a defined set of parameters. In order to provide a reliable repair, it is important to not only maintain the same processing parameters, but also to have optimum fixed parameters, such as the particle injection location. This study is intended to provide insight into the sensitivity of the way that the powder is injected upstream of supersonic nozzles in high-pressure cold spray systems and the effects of variations in injection parameters on the nature of the powder particle kinetics. Experimentally validated three-dimensional computational fluid dynamics (3D CFD) models are implemented to study the particle impact conditions for varying powder feeder tube size, powder feeder tube axial misalignment, and radial powder feeder injection location on the particle velocity and the deposition shape of aluminum alloy 6061. Outputs of the models are statistically analyzed to explore the shape of the spray plume distribution and resulting coating buildup.

  2. Real-time parameter optimization based on neural network for smart injection molding

    Science.gov (United States)

    Lee, H.; Liau, Y.; Ryu, K.

    2018-03-01

    The manufacturing industry has been facing several challenges, including sustainability, performance and quality of production. Manufacturers attempt to enhance the competitiveness of companies by implementing CPS (Cyber-Physical Systems) through the convergence of IoT(Internet of Things) and ICT(Information & Communication Technology) in the manufacturing process level. Injection molding process has a short cycle time and high productivity. This features have been making it suitable for mass production. In addition, this process is used to produce precise parts in various industry fields such as automobiles, optics and medical devices. Injection molding process has a mixture of discrete and continuous variables. In order to optimized the quality, variables that is generated in the injection molding process must be considered. Furthermore, Optimal parameter setting is time-consuming work to predict the optimum quality of the product. Since the process parameter cannot be easily corrected during the process execution. In this research, we propose a neural network based real-time process parameter optimization methodology that sets optimal process parameters by using mold data, molding machine data, and response data. This paper is expected to have academic contribution as a novel study of parameter optimization during production compare with pre - production parameter optimization in typical studies.

  3. Two-component microinjection moulding for MID fabrication

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Tang, Peter Torben

    2010-01-01

    Moulded interconnect devices (MIDs) are plastic substrates with electrical infrastructure. The fabrication of MIDs is usually based on injection moulding, and different process chains may be identified from this starting point. The use of MIDs has been driven primarily by the automotive sector......, but recently, the medical sector seems more and more interested. In particular, the possibility of miniaturisation of three-dimensional components with electrical infrastructure is attractive. The present paper describes possible manufacturing routes and challenges of miniaturised MIDs based on two...

  4. Impact of the injection dose of exhaust gases, on work parameters of combustion engine

    Science.gov (United States)

    Marek, W.; Śliwiński, K.

    2016-09-01

    This article is another one from the series in which were presented research results indicated the possible areas of application of the pneumatic injection using hot combustion gases proposed by Professor Jarnuszkiewicz. This publication present the results of the control system of exhaust gas recirculation. The main aim of this research was to determine the effect of exhaust gas recirculation to the operating parameters of the internal combustion engine on the basis of laboratory measurements. All measurements were performed at a constant engine speed. These conditions correspond to the operation of the motor operating an electrical generator. The study was conducted on the four-stroke two-cylinder engine with spark ignition. The study were specifically tested on the air injection system and therefore the selection of the rotational speed was not bound, as in conventional versions of operating parameters of the electrical machine. During the measurement there were applied criterion which used power control corresponding to the requirements of load power, at minimal values of engine speed. Recirculation value determined by the following recurrent position control valve of the injection doses inflator gas for pneumatic injection system. They were studied and recorded, the impact of dose of gases recirculation to the operating and ecological engine parameters such as power, torque, specific fuel consumption, efficiency, air fuel ratio, exhaust gas temperature and nitrogen oxides and hydrocarbons.

  5. Influence of Binding Rates on Strength Properties of Moulding Sands with the GEOPOL Binder

    Directory of Open Access Journals (Sweden)

    Holtzer M.

    2014-03-01

    Full Text Available The results of investigations of moulding sands with an inorganic binder called GEOPOL, developed by the SAND TEAM Company are presented in the paper. Hardeners of various hardening rates are used for moulding sands with this binder. The main aim of investigations was determination of the influence of the hardening rate of moulding sands with the GEOPOL binder on technological properties of these sands (bending strength, tensile strength, permeability and grindability. In addition, the final strength of moulding sands of the selected compositions was determined by two methods: by splitting strength and shear strength measurements. No essential influence of the hardening rate on such parameters as: permeability, grindability and final strength was found. However, the sand in which the slowest hardener (SA 72 were used, after 1 hour of holding, had the tensile and bending strength practically zero. Thus, the time needed for taking to pieces the mould made of such moulding sand will be 1.5 - 2 hours.

  6. Effect of hardening methods of moulding sands with water glass on structure of bonding bridges

    Directory of Open Access Journals (Sweden)

    M. Stachowicz

    2010-07-01

    Full Text Available Research on influence of hardening methods on structure of bonding bridges in moulding sands with sodium water glass is presented.Moulding sands with addition of 2.5 % of binder with molar module 2.0 were hardened with CO2 and dried in traditional way or hardenedwith microwaves. It was proved that the hardening method affects structure of bonding bridges, correlating with properties of the hardened moulding sands. It was found that strength of the moulding sands hardened with microwaves for 4 min is very close to that measured after traditional drying at 110 °C for 120 min. So, application of microwave hardening ensures significant shortening of the process time to the value comparable with CO2 hardening but guaranteeing over 10-fold increase of mechanical properties. Analysis of SEM images of hardened moulding sands permitted explaining differences in quality parameters of moulding sands by connecting them with structure of the created bonding bridges.

  7. Effects of pilot injection parameters on low temperature combustion diesel engines equipped with solenoid injectors featuring conventional and rate-shaped main injection

    International Nuclear Information System (INIS)

    D’Ambrosio, S.; Ferrari, A.

    2016-01-01

    Highlights: • The influence of the principal pilot injection parameters is discussed for low-temperature combustion systems. • Swirl-sweep and dwell-time sweep results are combined to analyze soot emissions. • The pilot injection effects are investigated in injection profiles featuring rate-shaped main injections. - Abstract: The potential of pilot injection has been assessed on a low-temperature combustion diesel engine for automotive applications, which was characterized by a reduced compression-ratio, high EGR rates and postponed main injection timings. Dwell time sweeps have been carried out for pilot injections with distinct energizing times under different representative steady-state working conditions of the medium load and speed area of the New European Driving Cycle. The results of in-cylinder analyses of the pressure, heat-release rate, temperature and emissions are presented. Combustion noise has been shown to decrease significantly when the pilot injected mass increases, while it is scarcely affected by the dwell time between the pilot and main injections. The HC, CO and fuel consumption trends, with respect to both the pilot injection dwell time and mass, are in line with those of conventional combustion systems, and in particular decreasing trends occur as the pilot injection energizing time is increased. Furthermore, a reduced sensitivity of NO_x emissions to both dwell time and pilot injected mass has been found, compared to conventional combustion systems. Finally, it has been observed that soot emissions diminish as the energizing time is shortened, and their dependence on dwell time is influenced to a great extent by the presence of local zones with reduced air-to-fuel ratios within the cylinder. A combined analysis of the results of swirl sweeps and dwell time sweeps is here proposed as a methodology for the detection of any possible interference between pilot combustion burned gases and the main injected fuel. The effect of pilot

  8. Plasma jet source parameter optimisation and experiments on injection into Globus-M spherical tokamak

    International Nuclear Information System (INIS)

    Gusev, V.K.; Petrov, Yu.V.; Sakharov, N.V.; Semenov, A.A.; Voronin, A.V.

    2005-01-01

    Results of theoretical and experimental research on the plasma sources and injection of plasma and gas jet produced by the modified source into tokamak Globus-M are presented. An experimental test stand was developed for investigation of intense plasma jet generation. Optimisation of pulsed coaxial accelerator parameters by means of analytical calculations is performed with the aim of achieving the highest flow velocity at limited coaxial electrode length and discharge current. The optimal parameters of power supply to generate a plasma jet with minimal impurity contamination and maximum flow velocity were determined. A comparison of experimental and calculation results is made. Plasma jet parameters are measured, such as: impurity species content, pressure distribution across the jet, flow velocity, plasma density, etc. Experiments on the interaction of a higher kinetic energy plasma jet with the magnetic field and plasma of the Globus-M tokamak were performed. Experimental results on plasma and gas jet injection into different Globus-M discharge phases are presented and discussed. Results are presented on the investigation of plasma jet injection as the source for discharge breakdown, plasma current startup and initial density rise. (author)

  9. The effect of plasma parameter on the bootstrap current of fast ions in neutral beam injection

    International Nuclear Information System (INIS)

    Huang Qianhong; Gong Xueyu; Cao Jinjia; Yang Lei

    2014-01-01

    The effect of plasma parameters on the distribution of net current density of fast ions produced by neutral beam injection is investigated in a large-aspect-ratio Tokamak with circular cross-section under specific parameters. Numerical results show that the value of net current density increases with the temperature of plasma increasing and decreases with the density of plasma increasing. The value of net current density is weakly affected by the effective charge number, but the peak of net current density moves towards edge plasma with effective charge number increasing. (authors)

  10. Numerical study on injection parameters optimization of thin wall and biodegradable polymers parts

    Science.gov (United States)

    Santos, C.; Mendes, A.; Carreira, P.; Mateus, A.; Malça, C.

    2017-07-01

    Nowadays, the molds industry searches new markets, with diversified and added value products. The concept associated to the production of thin walled and biodegradable parts mostly manufactured by injection process has assumed a relevant importance due to environmental and economic factors. The growth of a global consciousness about the harmful effects of the conventional polymers in our life quality associated with the legislation imposed, become key factors for the choice of a particular product by the consumer. The target of this work is to provide an integrated solution for the injection of parts with thin walls and manufactured using biodegradable materials. This integrated solution includes the design and manufacture processes of the mold as well as to find the optimum values for the injection parameters in order to become the process effective and competitive. For this, the Moldflow software was used. It was demonstrated that this computational tool provides an effective responsiveness and it can constitute an important tool in supporting the injection molding of thin-walled and biodegradable parts.

  11. A stone mould from Klinovac

    Directory of Open Access Journals (Sweden)

    Bulatović Aleksandar

    2002-01-01

    Full Text Available A two-piece stone mould that reached the National Museum at Vranje in 1966 had been recovered from a depth of about one meter at the site known as Tri Kruške (Three Pear-trees, the village of Klinovac. The site is situated on a river terrace on the right bank of the Krševica River some 15 kilometers south of Vranje. The mould was carved out of metamorphic rock from the class of schist, more exactly, of greenschist (with chlorite and mica as its constituent minerals that is widespread in the area, which geologically belongs to the upper (Vlasina complex of the Serbian-Macedonian mass. The mould was intended for casting four kinds of bronze weapons: three chisels and a winged axe. More sensitive as dating evidence, the winged axe (Ärmchenbeil may be broadly dated to the last three centuries of the second millennium BC. The type is geographically related with the Aegean, while its northernmost findspot so far is Pobit Kamak in northern Bulgaria. The chisels cast in this mould do not have direct analogies, although many hoards of similar tools have been registered in Croatia, Romania and Central Europe. Apparently the mould was made by a local workshop and from the locally available raw material. The possible activity of local workshops in the above mentioned period has already been presumed by scholars, and the Klinovac mould constitutes yet another corroboration of the hypothesis. Nevertheless its Aegean origin should not be ruled out completely, because cultural contacts between the Late Bronze Age population inhabiting the region and their southern neighbours seem quite certain, as evidenced by Mycenaean pottery discovered on the site of Resulja at Lučani near Bujanovac.

  12. Mould thermal monitoring: a window on the mould

    Energy Technology Data Exchange (ETDEWEB)

    Normanton, A.S.; Hewitt, P.N.; Hunter, N.S.; Scoones, D.; Harris, B.

    2004-07-01

    Corus R, D and T at Teesside Technology Centre has developed over a number of years a mould thermal monitoring (MTM) system based on an array of thermocouples in the mould copper plates. The system is installed on the Corus slab casters in the UK, on slab casters at Outokumpu (UK), Sidmar (Belgium) and Kosice (Slovakia) and, at the time of the 4th European Continuous Casting Conference, was also on the medium thickness slab caster at Tuscaloosa (USA), which was sold to Nucor in 2004. The MTM system was also under development on the thin slab caster at Trico (USA) before plant closure (subsequently bought by Nucor), and aspects are currently being developed on the Corus DSP (direct sheet plant) thin slab caster at IJmuiden (The Netherlands). While a prime function is detection and prevention of sticker type breakouts, the MTM system allows real time assessment of thermal conditions, provides a valuable input for online grading and, most important, enables modifications to mould powder practices to be assessed. The present paper briefly outlines recent developments to the MTM system and presents examples of the use of the system to assist mould powder developments. (author)

  13. Effect Of Pyridoxine Injection In Japanese Quail Eggs On HATCHABILITY, Performance And Some Physiological Parameters

    International Nuclear Information System (INIS)

    ELSAYED, M.A.; WAKWAK, M.M.; MAHROSE, KH.M.

    2010-01-01

    The present study was carried out at the poultry farm found in the Nuclear Research Center, Atomic Energy Authority, Inshas, Sharkia Governorate, Egypt, during January 2009. A total number of two hundreds and seventy five quail eggs were used in an experiment of a completely randomized design to estimate hatchability percentage, chick weight at hatch, growth performance, some blood parameters and carcass traits of Japanese quails as affected by injecting their eggs with pyridoxine. Eggs were divided into 5 groups (55 eggs each); the first group (without injection) was served as control while the second group was injected in the width end of the egg with 500 μl saline. The third, fourth and fifth groups were injected in the width end of the Japanese quail eggs with 40, 80 and 120 μg pyridoxine, respectively, dissolved in 500 μl saline. Hatchability percentage, live body weight, daily body weight gain and some organ weights (liver, gizzard and heart) were studied. At the end of the experiment, blood samples were collected for analyses. It was observed that the groups of quail eggs received 120 μg pyridoxine injection recorded the highest hatchability percent. Chick weight at hatch was non-significantly affected by saline solution injection. The birds hatched from the groups of quail eggs received 120μg pyridoxine recorded the highest live body weight, especially during the 2 nd and 3 rd weeks of age. The daily body weight gain was significantly affected by pyridoxine injection only during the intervals of 1 to 2, 3 to 4 and from 1 to 6 weeks of age. Serum total protein, albumin and globulin concentrations were highly significantly elevated in the birds hatched from the groups of quail eggs received 120μg pyridoxine than other groups. Serum AST activity was highly significantly increased in the birds hatched from the groups of quail eggs received 40 μg pyridoxine than other groups while serum ALT activity and calcium concentration were non

  14. Automatic estimation of aquifer parameters using long-term water supply pumping and injection records

    Science.gov (United States)

    Luo, Ning; Illman, Walter A.

    2016-09-01

    Analyses are presented of long-term hydrographs perturbed by variable pumping/injection events in a confined aquifer at a municipal water-supply well field in the Region of Waterloo, Ontario (Canada). Such records are typically not considered for aquifer test analysis. Here, the water-level variations are fingerprinted to pumping/injection rate changes using the Theis model implemented in the WELLS code coupled with PEST. Analyses of these records yield a set of transmissivity ( T) and storativity ( S) estimates between each monitoring and production borehole. These individual estimates are found to poorly predict water-level variations at nearby monitoring boreholes not used in the calibration effort. On the other hand, the geometric means of the individual T and S estimates are similar to those obtained from previous pumping tests conducted at the same site and adequately predict water-level variations in other boreholes. The analyses reveal that long-term municipal water-level records are amenable to analyses using a simple analytical solution to estimate aquifer parameters. However, uniform parameters estimated with analytical solutions should be considered as first rough estimates. More accurate hydraulic parameters should be obtained by calibrating a three-dimensional numerical model that rigorously captures the complexities of the site with these data.

  15. Mould growth on building materials

    DEFF Research Database (Denmark)

    Fog Nielsen, K.

    Mould growth in buildings is associated with adverse health effects among the occupants of the building. However actual growth only occurs in damp and water-damaged materials, and is an increasing problem in Denmark, due to less robust constructions, inadequate maintenance, and too little...

  16. Optimizing Injection Molding Parameters of Different Halloysites Type-Reinforced Thermoplastic Polyurethane Nanocomposites via Taguchi Complemented with ANOVA

    Directory of Open Access Journals (Sweden)

    Tayser Sumer Gaaz

    2016-11-01

    Full Text Available Halloysite nanotubes-thermoplastic polyurethane (HNTs-TPU nanocomposites are attractive products due to increasing demands for specialized materials. This study attempts to optimize the parameters for injection just before marketing. The study shows the importance of the preparation of the samples and how well these parameters play their roles in the injection. The control parameters for injection are carefully determined to examine the mechanical properties and the density of the HNTs-TPU nanocomposites. Three types of modified HNTs were used as untreated HNTs (uHNTs, sulfuric acid treated (aHNTs and a combined treatment of polyvinyl alcohol (PVA-sodium dodecyl sulfate (SDS-malonic acid (MA (treatment (mHNTs. It was found that mHNTs have the most influential effect of producing HNTs-TPU nanocomposites with the best qualities. One possible reason for this extraordinary result is the effect of SDS as a disperser and MA as a crosslinker between HNTs and PVA. For the highest tensile strength, the control parameters are demonstrated at 150 °C (injection temperature, 8 bar (injection pressure, 30 °C (mold temperature, 8 min (injection time, 2 wt % (HNTs loading and mHNT (HNTs type. Meanwhile, the optimized combination of the levels for all six control parameters that provide the highest Young’s modulus and highest density was found to be 150 °C (injection temperature, 8 bar (injection pressure, 32 °C (mold temperature, 8 min (injection time, 3 wt % (HNTs loading and mHNT (HNTs type. For the best tensile strain, the six control parameters are found to be 160 °C (injection temperature, 8 bar (injection pressure, 32 °C (mold temperature, 8 min (injection time, 2 wt % (HNTs loading and mHNT (HNTs type. For the highest hardness, the best parameters are 140 °C (injection temperature, 6 bar (injection pressure, 30 °C (mold temperature, 8 min (injection time, 2 wt % (HNTs loading and mHNT (HNTs type. The analyses are carried out by coordinating

  17. Tablet coating by injection molding technology - Optimization of coating formulation attributes and coating process parameters.

    Science.gov (United States)

    Desai, Parind M; Puri, Vibha; Brancazio, David; Halkude, Bhakti S; Hartman, Jeremy E; Wahane, Aniket V; Martinez, Alexander R; Jensen, Keith D; Harinath, Eranda; Braatz, Richard D; Chun, Jung-Hoon; Trout, Bernhardt L

    2018-01-01

    We developed and evaluated a solvent-free injection molding (IM) coating technology that could be suitable for continuous manufacturing via incorporation with IM tableting. Coating formulations (coating polymers and plasticizers) were prepared using hot-melt extrusion and screened via stress-strain analysis employing a universal testing machine. Selected coating formulations were studied for their melt flow characteristics. Tablets were coated using a vertical injection molding unit. Process parameters like softening temperature, injection pressure, and cooling temperature played a very important role in IM coating processing. IM coating employing polyethylene oxide (PEO) based formulations required sufficient room humidity (>30% RH) to avoid immediate cracks, whereas other formulations were insensitive to the room humidity. Tested formulations based on Eudrajit E PO and Kollicoat IR had unsuitable mechanical properties. Three coating formulations based on hydroxypropyl pea starch, PEO 1,000,000 and Opadry had favorable mechanical (35% elongation, >95×10 4 J/m 3 toughness) and melt flow (>0.4g/min) characteristics, that rendered acceptable IM coats. These three formulations increased the dissolution time by 10, 15 and 35min, respectively (75% drug release), compared to the uncoated tablets (15min). Coated tablets stored in several environmental conditions remained stable to cracking for the evaluated 8-week time period. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Deterioration of the fuel injection parameters as a result of Common Rail injectors deposit formation

    Directory of Open Access Journals (Sweden)

    Stępień Zbigniew

    2017-01-01

    Full Text Available The article describes external and internal Common Rail injectors deposits formed in dynamometer engine simulation tests. It discussed not only the key reasons and factors influencing injector deposit formation but also the resulting way of fuel preparation and engine test approaches. The effects of external coking deposit as well as internal deposits two most common form types that is carboxylic soaps and organic amides on deterioration of the fuel injection parameters were assessed. The assessments covered both deposits impacts on quantitative and qualitative changes of the injectors diagnostic parameters and as a result on deterioration of the injector performance. Finally the comparisons between characteristic of dosage of one fuel injector before test and characteristics few injectors after engine tests of simulated deposit formation were made.

  19. Evaluation of wettability of binders used in moulding sands

    Directory of Open Access Journals (Sweden)

    Hutera B.

    2007-01-01

    Full Text Available Binders used in moulding sand have the differential properties. One of the main parameters influencing on moulding sand properties is wettability of the sand grain by binding material. In the article some problems concerned with wettability evaluation have been presented and the importance of this parameter for quantity description of process occurring in system: binder- sand grain has been mentioned. The procedure of wetting angle measurement and operation of prototype apparatus for wettability investigation of different binders used in moulding sand have been described, as well as the results of wetting angle measurement for different binders at different conditions. The addition of little amount of proper diluent to binder results in the state of equilibrium reached almost immediately. Such addition can also reduce the value of equilibrium contact angle. The uniform distribution of binder on the surface of the sand grains and reducing of the required mixing time can be obtained. It has also a positive effect on the moulding sand strength.

  20. Investigation of ecological parameters of four-stroke SI engine, with pneumatic fuel injection system

    Science.gov (United States)

    Marek, W.; Śliwiński, K.

    2016-09-01

    The publication presents the results of tests to determine the impact of using waste fuels, alcohol, to power the engine, on the ecological parameters of the combustion engine. Alternatively fuelled with a mixture of iso- and n-butanol, indicated with "X" and "END, and gasoline and a mixture of fuel and alcohol. The object of the study was a four-stroke engine with spark ignition designed to work with a generator. Motor power was held by the modified system of pneumatic injection using hot exhaust gases developed by Prof. Stanislaw Jarnuszkiewicz, controlled by modern mechatronic systems. Tests were conducted at a constant speed for the intended use of the engine. The subject of the research was to determine the control parameters such as ignition timing, mixture composition and the degree of exhaust gas recirculation on the ecological parameters of the engine. Tests were carried out using partially quality power control. In summary we present the findings of this phase of the study.

  1. Optimization of control parameters for SR in EDM injection flushing type on stainless steel 304 workpiece

    International Nuclear Information System (INIS)

    Reza, M S; Yusoff, A R; Shaharun, M A

    2012-01-01

    The operating control parameters of injection flushing type of electrical discharge machining process on stainless steel 304 workpiece with copper tools are being optimized according to its individual machining characteristic i.e. surface roughness (SR). Higher SR during EDM machining process results for poor surface integrity of the workpiece. Hence, the quality characteristic for SR is set to lower-the-better to achieve the optimum surface integrity. Taguchi method has been used for the construction, layout and analysis of the experiment for each of the machining characteristic for the SR. The use of Taguchi method in the experiment saves a lot of time and cost of machining the experiment samples. Therefore, an L18 Orthogonal array which was the fundamental component in the statistical design of experiments has been used to plan the experiments and Analysis of Variance (ANOVA) is used to determine the optimum machining parameters for this machining characteristic. The control parameters selected for this optimization experiments are polarity, pulse on duration, discharge current, discharge voltage, machining depth, machining diameter and dielectric liquid pressure. The result had shown that the lower the machining diameter, the lower will be the SR.

  2. Evaluation of reconstruction parameters of electrical impedance tomography on aorta detection during saline bolus injection

    Directory of Open Access Journals (Sweden)

    Thürk Florian

    2016-09-01

    Full Text Available An accurate detection of anatomical structures in electrical impedance tomography (EIT is still at an early stage. Aorta detection in EIT is of special interest, since it would favor non-invasive assessment of hemodynamic processes in the body. Here, diverse EIT reconstruction parameters of the GREIT algorithm were systematically evaluated to detect the aorta after saline bolus injection in apnea. True aorta position and size were taken from computed tomography (CT. A comparison with CT showed that the smallest error for aorta displacement was attained for noise figure nf = 0.7, weighting radius rw = 0.15, and target size ts = 0.01. The spatial extension of the aorta was most precise for nf = 0.7, rw = 0.25, and ts = 0.07. Detection accuracy (F1-score was highest with nf = 0.6, rw = 0.15, and ts = 0.04. This work provides algorithm-related evidence for potentially accurate aorta detection in EIT after injection of a saline bolus.

  3. Solar wind parameters responsible for the plasma injection into the magnetospheric ring current region

    International Nuclear Information System (INIS)

    Bobrov, M.S.

    1977-01-01

    Solar wind effect on the magnetospheric ring-current region has been considered. The correlations with solar wind parameters of the magnitude qsub(o) proportional to the total energy of particles being injected into the magnetospheric ring-current region per one hour are studied statistically and by comparison of time variations. The data on 8 sporadic geomagnetic storms of various intensity, from moderate to very severe one, are used. It is found that qsub(o) correlates not only with the magnitude and the direction of the solar-wind magnetic field component normal to the ecliptic plane, Bsub(z), but also with the variability, sigmasub(B), of the total magnetic-field strength vector. The solar-wind flux velocity ν influences the average storm intensity but the time variations of ν during any individual storm do not correlate with those of qsub(o)

  4. Assessing the stretch-blow moulding FE simulation of PET over a large process window

    Science.gov (United States)

    Nixon, J.; Menary, G. H.; Yan, S.

    2017-10-01

    Injection stretch blow moulding has been extensively researched for numerous years and is a well-established method of forming thin-walled containers. This paper is concerned with validating the finite element analysis of the stretch-blow-moulding (SBM) process in an effort to progress the development of injection stretch blow moulding of poly(ethylene terephthalate). Extensive data was obtained experimentally over a wide process window accounting for material temperature, air flow rate and stretch-rod speed while capturing cavity pressure, stretch-rod reaction force, in-mould contact timing and material thickness distribution. This data was then used to assess the accuracy of the correlating FE simulation constructed using ABAQUS/Explicit solver and an appropriate user-defined viscoelastic material subroutine. Results reveal that the simulation was able to pick up the general trends of how the pressure, reaction force and in-mould contact timings vary with the variation in preform temperature and air flow rate. Trends in material thickness were also accurately predicted over the length of the bottle relative to the process conditions. The knowledge gained from these analyses provides insight into the mechanisms of bottle formation, subsequently improving the blow moulding simulation and potentially providing a reduction in production costs.

  5. Scanning probe lithography for nanoimprinting mould fabrication

    International Nuclear Information System (INIS)

    Luo Gang; Xie Guoyong; Zhang Yongyi; Zhang Guoming; Zhang Yingying; Carlberg, Patrick; Zhu Tao; Liu Zhongfan

    2006-01-01

    We propose a rational fabrication method for nanoimprinting moulds by scanning probe lithography. By wet chemical etching, different kinds of moulds are realized on Si(110) and Si(100) surfaces according to the Si crystalline orientation. The structures have line widths of about 200 nm with a high aspect ratio. By reactive ion etching, moulds with patterns free from the limitation of Si crystalline orientation are also obtained. With closed-loop scan control of a scanning probe microscope, the length of patterned lines is more than 100 μm by integrating several steps of patterning. The fabrication process is optimized in order to produce a mould pattern with a line width about 10 nm. The structures on the mould are further duplicated into PMMA resists through the nanoimprinting process. The method of combining scanning probe lithography with wet chemical etching or reactive ion etching (RIE) provides a resistless route for the fabrication of nanoimprinting moulds

  6. Sealing of polymer micro-structures by over-moulding

    DEFF Research Database (Denmark)

    Vingaard, Mathias; Christiansen, Jesper de Claville

    2012-01-01

    A concept for sealing of polymer micro-structures by over-moulding with polystyrene was devised and investigated by both experiments and simulations. The depth to which the melt filled the structure, i.e. a groove in the surface of the insert, before solidification was compared with results from...... simulations by computational fluid dynamics software. In both experiments and simulations, there was clearly an increase of filling depth with groove width and, especially for wide grooves, with injection temperature. In the simulations, changes in prescribed heat transfer coefficient had the largest effect...... on filling depth in the narrowest grooves. Around the experimental groove widths, there was good agreement between experiments and simulations. It was concluded that sealing by over-moulding is feasible if the depth/width ratio of the structure is large enough which in this paper is larger than six, i.e. up...

  7. Effect of injection parameters on mechanical and physical properties of super ultra-thin wall propylene packaging by Taguchi method

    Science.gov (United States)

    Ginghtong, Thatchanok; Nakpathomkun, Natthapon; Pechyen, Chiravoot

    2018-06-01

    The parameters of the plastic injection molding process have been investigated for the manufacture of a 64 oz. ultra-thin polypropylene bucket. The 3 main parameters, such as injection speed, melting temperature, holding pressure, were investigated to study their effect on the physical appearance and compressive strength. The orthogonal array of Taguchi's L9 (33) was used to carry out the experimental plan. The physical properties were measured and the compressive strength was determined using linear regression analysis. The differential scanning calorimeter (DSC) was used to analyze the crystalline structure of the product. The optimization results show that the proposed approach can help engineers identify optimal process parameters and achieve competitive advantages of energy consumption and product quality. In addition, the injection molding of the product includes 24 mm of shot stroke, 1.47 mm position transfer, 268 rpm screw speed, injection speed 100 mm/s, 172 ton clamping force, 800 kgf holding pressure, 0.9 s holding time and 1.4 s cooling time, make the products in the shape and proportion of the product satisfactory. The parameters of influence are injection speed 71.07%, melting temperature 23.31% and holding pressure 5.62%, respectively. The compressive strength of the product was able to withstand a pressure of up to 839 N before the product became plastic. The low melting temperature was caused by the superior crystalline structure of the super-ultra-thin wall product which leads to a lower compressive strength.

  8. DEVELOPMENT OF FLUORINE-FREE MOULD FLUX APPLIED IN LOW CARBON STEEL

    Directory of Open Access Journals (Sweden)

    Jayme Alves de Souza Junior

    2012-12-01

    Full Text Available ract The mould flux is a mixture of non-metallic oxides that, in contact with liquid steel melts, becomes a liquid slag which the mainly function is to lubricate and control heat transfer between mould and strand during the continuous casting process. The mould flux without fluoride has the advantage of decreasing the wear of machine and the SEN in comparison to common mould flux. The application in Continuous Casting of Slabs has been a great challenge in relation to the operational viability together with internal and surface quality of slabs. Another differential is the decrease of environmental issues on account of the contamination of secondary cooling water by the fluorides. It is considered that properties of mould flux as chemical composition, viscosity, softening, melting flowing temperatures, fusion rate, etc, should be suitable to the chemical composition and the mechanical properties at elevated temperatures of steel and also the operational parameters such as casting temperature, casting speed, mould frequency, among others. This work presents a preliminary analysis in relation to operational viability, analysis of surface quality of slabs, measurements of fluorides content in the water of secondary cooling of machine. In addition to that, the analyses of operational features as measurements of wear of SEN, mould flux consumption, slag pool and behavior of thermocouples of detection system break outs (MSD are considered.

  9. Dynamic Double Curvature Mould System

    DEFF Research Database (Denmark)

    Jepsen, Christian Raun; Kristensen, Mathias Kræmmergaard; Kirkegaard, Poul Henning

    2011-01-01

    The present paper describes a concept for a reconfigurable mould surface which is designed to fit the needs of contemporary architecture. The core of the concept presented is a dynamic surface manipulated into a given shape using a digital signal created directly from the CAD drawing of the design....... This happens fast, automatic and without production of waste, and the manipulated surface is fair and robust, eliminating the need for additional, manual treatment. Limitations to the possibilities of the flexible form are limited curvature and limited level of detail, making it especially suited for larger...

  10. Properties and parameters of the electron beam injected into the mirror magnetic trap of a plasma accelerator

    Energy Technology Data Exchange (ETDEWEB)

    Andreev, V. V., E-mail: temple18@mail.ru; Novitsky, A. A.; Vinnichenko, L. A.; Umnov, A. M.; Ndong, D. O. [Peoples’ Friendship University of Russia (Russian Federation)

    2016-03-15

    The parameters of the injector of an axial plasma beam injected into a plasma accelerator operating on the basis of gyroresonance acceleration of electrons in the reverse magnetic field are determined. The trapping of the beam electrons into the regime of gyroresonance acceleration is numerically simulated by the particle- in-cell method. The optimal time of axial injection of the beam into a magnetic mirror trap is determined. The beam parameters satisfying the condition of efficient particle trapping into the gyromagnetic autoresonance regime are found.

  11. Simulation of mould filling process for composite skeleton castings

    OpenAIRE

    M. Dziuba; M. Cholewa

    2008-01-01

    In this work authors showed selected results of simulation and experimental studies on temperature distribution during solidification of skeleton casting and mould filling process. The aim of conducted simulations was the choice of thermal and geometrical parameters for the needs of designed calculations of the skeleton castings and the estimation of the guidelines for the technology of manufacturing. The subject of numerical simulation was the analysis of ability of filling the channels of c...

  12. A proper strategy for combating mould.

    Science.gov (United States)

    Cheong, Cedric

    2014-02-01

    managing director of Mycologia & Mould Worx, MSc, B.(Env. Sci.), TAE40110, examines the topic of mould exposure in healthcare facilities, and the associated duty of care for hospital facility managers and engineers. The article, published here in slightly adapted form, also focuses on the need for additional training of key personnel on the risks associated with exposure to environmental microbial contamination.

  13. Assessment Method of Overheating Degree of a Spent Moulding Sand with Organic Binder, After the Casting Process

    Directory of Open Access Journals (Sweden)

    Dańko R.

    2013-06-01

    Full Text Available A proper management of sand grains of moulding sands requires knowing basic properties of the spent matrix after casting knocking out. This information is essential from the point of view of the proper performing the matrix recycling process and preparing moulding sands with reclaimed materials. The most important parameter informing on the matrix quality - in case of moulding sands with organic binders after casting knocking out - is their ignition loss. The methodology of estimating ignition loss of spent moulding sands with organic binder - after casting knocking out - developed in AGH, is presented in the paper. This method applies the simulation MAGMA software, allowing to determine this moulding sand parameter already at the stage of the production preparation.

  14. Evaluation of the viscoelastic behaviour and glass/mould interface friction coefficient in the wafer based precision glass moulding

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Hattel, Jesper Henri; Hansen, Hans Nørgaard

    2014-01-01

    -placements, internal diameter and thickness of the rings are measured during the tests. Viscoelastic andstructural relaxation behaviour of the glass are implemented into the ABAQUS FEM software through aFORTRAN material subroutine (UMAT) and the FE model is validated with a sandwich seal test. Then, byFE simulation...... of the ring compression test and comparison of the experimental creep with the simulatedone in an iterative procedure, viscoelastic parameters of the glass material are characterized. Finally,interfacial glass/mould friction coefficients at different temperatures are determined through FEM basedfriction...... curves combined with experimental data points. The obtained viscoelastic parameters and inter-facial friction coefficients can later be employed for prediction of the final shape/size as well as the stressdistribution in the glass wafer during a real wafer based precision glass moulding process. © 2014...

  15. Moulds and indoor air quality - a man-made problem

    International Nuclear Information System (INIS)

    Langvad, Finn

    2002-01-01

    In the 1970s and 1980s, many house owners in Norway, in order to save energy, insulated their houses by injecting torn-up mineral wool into the entire cavity of the wall. This made the house warmer to live in, but it also created serious condensation problems followed by rot and mould. The extensive use of gypsum boards is also alarming. If gypsum becomes really wet because of a water leakage, it becomes a ticking bomb from the micro-biologic point of view as it provides growth conditions for some of the most dangerous indoor mould fungi known, the Stachybotrys chart arum. The article discusses the danger of this fungus and surveys some of the ways that mould affect human health. There is at present no definition of a normal number of fungus spores per unit volume of air. But the following principles can be taken as guidelines: (1) The concentration of spores indoor must be lower than outdoors. Otherwise extra spores have been generated in the house. (2) The species composition of the air must be approximately the same indoors and outdoors

  16. Effects of Pre and Post-Rigor Marinade Injection on Some Quality Parameters of Longissimus Dorsi Muscles

    Science.gov (United States)

    Fadıloğlu, Eylem Ezgi; Serdaroğlu, Meltem

    2018-01-01

    Abstract This study was conducted to evaluate the effects of pre and post-rigor marinade injections on some quality parameters of Longissimus dorsi (LD) muscles. Three marinade formulations were prepared with 2% NaCl, 2% NaCl+0.5 M lactic acid and 2% NaCl+0.5 M sodium lactate. In this study marinade uptake, pH, free water, cooking loss, drip loss and color properties were analyzed. Injection time had significant effect on marinade uptake levels of samples. Regardless of marinate formulation, marinade uptake of pre-rigor samples injected with marinade solutions were higher than post rigor samples. Injection of sodium lactate increased pH values of samples whereas lactic acid injection decreased pH. Marinade treatment and storage period had significant effect on cooking loss. At each evaluation period interaction between marinade treatment and injection time showed different effect on free water content. Storage period and marinade application had significant effect on drip loss values. Drip loss in all samples increased during the storage. During all storage days, lowest CIE L* value was found in pre-rigor samples injected with sodium lactate. Lactic acid injection caused color fade in pre-rigor and post-rigor samples. Interaction between marinade treatment and storage period was found statistically significant (p<0.05). At day 0 and 3, the lowest CIE b* values obtained pre-rigor samples injected with sodium lactate and there were no differences were found in other samples. At day 6, no significant differences were found in CIE b* values of all samples. PMID:29805282

  17. Laser cleaning of the contaminations on the surface of tire mould

    Science.gov (United States)

    Ye, Yayun; Jia, Baoshen; Chen, Jing; Jiang, Yilan; Tang, Hongping; Wang, Haijun; Luan, Xiaoyu; Liao, Wei; Zhang, Chuanchao; Yao, Caizhen

    2017-07-01

    During the manufacturing of tires, surface pollutants on tire mould will lead to the production of unqualified tires. Tire moulds need to be regularly cleaned. Laser cleaning is recognized as a non-destructive, effective, precise and environmental friendly method. In this paper, laser cleaning was used to remove contaminants on tire mould surface. First, laser induced damage experiments were performed. The results showed that the roughness and hardness of the cast steel sample surface seldom changed under the energy range of 140.1-580.2 mJ laser irradiation 1 pulse and the energy range of 44.7-168.9 mJ laser irradiation 100 pulses. In the laser cleaning experiments, the cleaning thresholds and the optimal cleaning parameters were obtained. Results indicated that laser cleaning was safe and effective for tire mould contamination removal.

  18. Estimation of operational parameters for a direct injection turbocharged spark ignition engine by using regression analysis and artificial neural network

    Directory of Open Access Journals (Sweden)

    Tosun Erdi

    2017-01-01

    Full Text Available This study was aimed at estimating the variation of several engine control parameters within the rotational speed-load map, using regression analysis and artificial neural network techniques. Duration of injection, specific fuel consumption, exhaust gas at turbine inlet, and within the catalytic converter brick were chosen as the output parameters for the models, while engine speed and brake mean effective pressure were selected as independent variables for prediction. Measurements were performed on a turbocharged direct injection spark ignition engine fueled with gasoline. A three-layer feed-forward structure and back-propagation algorithm was used for training the artificial neural network. It was concluded that this technique is capable of predicting engine parameters with better accuracy than linear and non-linear regression techniques.

  19. Measurement of micro moulded parts by Computed Tomography and comparison to optical and tactile techniques

    DEFF Research Database (Denmark)

    Yagüe, J.A.; Tosello, Guido; Carmignato, S

    2011-01-01

    This paper focuses on dimensional verification of two micro-injection moulded components, selected from actual industrial productions, using CT metrological tools. In addition to CT scanning, also a tactile Coordinate Measuring Machine (CMM) with sub-micrometer uncertainty and an Optical Coordinate...... Measuring Machine (OCMM) allowing fast measurements suitable for in-line quality control were employed as validation instruments. The experimental work carried out and the analysis of the results provide valuable conclusions about the advantages and drawbacks of using CT metrology in comparison with CMM...... and OCMM when these techniques are employed for quality control of micro moulded parts....

  20. A capability study of micro moulding for nano fluidic system manufacture

    DEFF Research Database (Denmark)

    Calaon, Matteo; Hansen, Hans Nørgaard; Tosello, Guido

    2013-01-01

    With the present paper the authors analysed process capability of ultra-precision moulding used for producing nano crosses with the same critical channels dimensions of a nano fluidic system for optical mapping of genomic length DNA. The process variation focused on product tolerances is quantified...... through AFM measurements. Uncertainty assessment of measurements on polymer objects is described and quality control results of sub-micro injection moulded crosses are shown in respect of the tolerance range specified by the end user as limit value for functional design....

  1. Active binder content as a factor of the control system of the moulding sand quality

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2011-01-01

    Full Text Available One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broaderapplication in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castingsand supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressurecastings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is theassessment method of sands suitability by means of detecting correlations between their individual parameters. The presentedinvestigations were obtained by using the Statistica 9.0 program. The presented investigations were aimed at the selection of the neuralnetwork able to predict the active bentonite content in the moulding sand on the basis of this sand properties such as: permeability,compactibility and the compressive strength. An application of the Statistica program allowed to select automatically the type of networkproper for the representation of dependencies occurring in between the proposed moulding sand parameters. The most advantageousconditions were obtained for the uni-directional multi-layer perception (MLP network. Knowledge of the neural network sensitivity to individual moulding sand parameters, allowed to eliminate not essential ones.

  2. Dilatometric examination of moulds with plaster binder

    Directory of Open Access Journals (Sweden)

    M. Nadolski

    2011-01-01

    Full Text Available Investigations concerning thermal expansion of moulding materials with plaster binder have been performed for two mixture compositionsof Authors’ own design, as well as for the material used in jewellery industry under the Prima-Cast trade name, and for ThermoMold 1200moulding material. The results of dilatometric examinations of these materials, carried out within the temperature range from about 20°Cto 650°C by means of the DA-3 automatic dilatometer, have been compared. An analysis of this comparison has revealed that it is thematrix composition which is decisive for the magnitude of dimensional changes of moulds, and that applying components which do notexhibit polymorphic transformations reduces dimensional changes of a mould during its thermal treatment.

  3. Two underestimated threats in food transportation: mould and acceleration.

    Science.gov (United States)

    Janssen, S; Pankoke, I; Klus, K; Schmitt, K; Stephan, U; Wöllenstein, J

    2014-06-13

    Two important parameters are often neglected in the monitoring of perishable goods during transport: mould contamination of fresh food and the influence of acceleration or vibration on the quality of a product. We assert the claim that it is necessary to focus research on these two topics in the context of intelligent logistics in this opinion paper. Further, the technical possibilities for future measurement systems are discussed. By measuring taste deviations, we verified the effect on the quality of beer at different vibration frequencies. The practical importance is shown by examining transport routes and market shares. The general feasibility of a mobile mould detection system is established by examining the measurement resolution of semiconductor sensors for mould-related gases. Furthermore, as an alternative solution, we present a concept for a miniaturized and automated culture-medium-based system. Although there is a lack of related research to date, new efforts can make a vital contribution to the reduction of losses in the logistic chains for several products.

  4. The influence of technological parameters on the dynamic behavior of "liquid wood" samples obtained by injection molding

    Science.gov (United States)

    Plavanescu Mazurchevici, Simona; Carausu, Constantin; Comaneci, Radu; Nedelcu, Dumitru

    2017-10-01

    The plastic products contribute to environmental pollution. Replacing the plastic materials with biodegradable materials with superior properties is an absolute necessity and important research direction for the near future. The first steps in this regard were the creation of composite materials containing natural fibers with positive effects on the environment that have penetrated in different fields. The bioplastics and biocomposites made from natural fibers is a topical solution. The next step was made towards obtaining biodegradable and recyclable materials based on cellulose, lignin and no carcinogens. In this category fall the "liquid wood" with a use up to five times without affecting the mechanical properties. "Liquid wood" is a high quality thermoplastic biocomposite. "Liquid wood" is a biopolymer composite divided in three categories, ARBOFORM®, ARBOBLEND® and ARBOFILL®, which have differed composition in terms of lignin percentage, being delivered by Tecnaro, as granules, [1]. The paper's research was focus on Arboform L V3 Nature and Arboform L V3 Nature reinforced with aramid fiber. In the experimental plan were taken into account six parameters (Dinj - direction of injection [°]; Ttop - melting temperature [°C]; Pinj - injection pressure [MPa] Ss - speed [m/min]; tinj - injection time [s] and tc - cooling time [s]) each with two levels, research carried on by Taguchi methodology. Processing Taguchi method allowed both Taguchi setting work parameters influence on storage modulus and damping as the size and influence their ranking. Experimental research concerning the influence technological parameters on storage modulus of samples obtained by injection from Arboform L V3 Nature yielded an average of 6055MPa and descending order as follows: Trac, Ss, Pinj, Dinj and Ttop. The average of model for reinforced material was 6419MPa and descending order of parameters influence such as: Dinj, Trac, Ttop, tinj, Ss and Pinj.

  5. Impact of hydrogeological and geomechanical properties on surface uplift at a CO2 injection site: Parameter estimation and uncertainty quantification

    Science.gov (United States)

    Newell, P.; Yoon, H.; Martinez, M. J.; Bishop, J. E.; Arnold, B. W.; Bryant, S.

    2013-12-01

    It is essential to couple multiphase flow and geomechanical response in order to predict a consequence of geological storage of CO2. In this study, we estimate key hydrogeologic features to govern the geomechanical response (i.e., surface uplift) at a large-scale CO2 injection project at In Salah, Algeria using the Sierra Toolkit - a multi-physics simulation code developed at Sandia National Laboratories. Importantly, a jointed rock model is used to study the effect of postulated fractures in the injection zone on the surface uplift. The In Salah Gas Project includes an industrial-scale demonstration of CO2 storage in an active gas field where CO2 from natural gas production is being re-injected into a brine-filled portion of the structure downdip of the gas accumulation. The observed data include millimeter scale surface deformations (e.g., uplift) reported in the literature and injection well locations and rate histories provided by the operators. Our preliminary results show that the intrinsic permeability and Biot coefficient of the injection zone are important. Moreover pre-existing fractures within the injection zone affect the uplift significantly. Estimation of additional (i.e., anisotropy ratio) and coupled parameters will help us to develop models, which account for the complex relationship between mechanical integrity and CO2 injection-induced pressure changes. Uncertainty quantification of model predictions will be also performed using various algorithms including null-space Monte Carlo and polynomial-chaos expansion methods. This work will highlight that our coupled reservoir and geomechanical simulations associated with parameter estimation can provide a practical solution for designing operating conditions and understanding subsurface processes associated with the CO2 injection. This work is supported as part of the Center for Frontiers of Subsurface Energy Security, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office

  6. The Impact of Microwave Penetration Depth on the Process of Heating the Moulding Sand with Sodium Silicate

    Directory of Open Access Journals (Sweden)

    Nowak D.

    2017-12-01

    Full Text Available This paper presents the impact of microwave penetration depth on the process of heating the moulding sand with sodium silicate. For each material it is affected by: the wavelength in vacuum and the real and imaginary components of the relative complex electrical permittivity εr for a selected measurement frequency. Since the components are not constant values and they change depending on the electrical parameters of materials and the frequency of the electromagnetic wave, it is indispensable to carry out laboratory measurements to determine them. Moreover, the electrical parameters of materials are also affected by: temperature, packing degree, humidity and conductivity. The measurements of the dielectric properties of moulding sand with sodium silicate was carried out using the perturbation method on a stand of waveguide resonance cavity. The real and imaginary components of the relative complex electrical permittivity was determined for moulding sand at various contents of sodium silicate and at various packing degrees of the samples. On the basis of the results the microwave penetration depth of moulding sand with sodium silicate was established. Relative literature contains no such data that would be essential to predicting an effective process of microwave heating of moulding sand with sodium silicate. Both the packing degree and the amount of sodium silicate in moulding sand turned out to affect the penetration depth, which directly translates into microwave power density distribution in the process of microwave heating of moulding sand with sodium silicate.

  7. Parameter Dependence of Inward Diffusion on Injected Electrons in Helical Non-Neutral Plasmas

    International Nuclear Information System (INIS)

    Wakabayashi, H.; Himura, H.; Fukao, M.; Yoshida, Z.

    2003-01-01

    Experimental studies on an electron injection into a helical magnetic field and characteristics of non-neutral plasmas have been performed. It is found that the space potential φs has a weak dependence on the injection angle except for a narrow 'window' region in which φs significantly drops. A calculation shows that because of the electric field Eg of the electron gun (e-gun), the emitted electrons are launched quasi-parallel to the helical magnetic field B, regardless of α. This seems to agree with the observation. The 'window' seen in the data may be attributed to an current-driven instability which might result in the insufficient electron penetration or the degradation of electron confinement in the magnetic surface

  8. Study on effect of mixing mechanism by the transverse gaseous injection flow in scramjet engine with variable parameters

    Science.gov (United States)

    Yadav, Siddhita; Pandey, K. M.

    2018-04-01

    In scramjet engine the mixing mechanism of fuel and atmospheric air is very complicated, because the fuel have time in milliseconds for mixing with atmospheric air in combustion chamber having supersonic speed. Mixing efficiency of fuel and atmospheric air depends on mainly these parameters: Aspect ratio of injector, vibration amplitude, shock type, number of injector, jet to transverse flow momentum flux ratio, injector geometry, injection angle, molecular weight, incoming air stream angle, jet to transverse flow pressure ratio, spacing variation, mass flow rate of fuel etc. here is a very brief study of these parameters from previously done research on these parameters for the improvement of mixing efficiency. The mixing process have the significant role for the working of engine, and mixing between the atmospheric air and the jet fuel is significant factor for improving the overall thrust of the engine. The results obtained by study of papers are obtained by the 3D-Reynolds Average-Nervier-Stokes(RANS) equations along with the 2-equation k-ω shear-stress-transport (SST) turbulence model. Engine having multi air jets have 60% more mixing efficiency than single air jet, thus if the jets are increased, the mixing efficiency of engine can also be increased up to 150% by changing jet from 1 to 16. When using delta shape of injector the mixing efficiency is inversely proportional to the pressure ratio. When the fuel is injected inside the combustor from the top and bottom walls of the engine efficiency of mixing in reacting zone is higher than the single wall injection and in comparison to parallel flow, the transverse type flow is better as the atmospheric air jet can penetrate smoothly in the fuel jets and mixes well in less time. Hence this study of parameters and their effects on mixing can enhance the efficiency of mixing in engine.

  9. ANN modelling for the determination of moulding sand matrix grain size

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2011-10-01

    Full Text Available One of the modern methods of the production optimisation are artificial neural networks. Neural networks are gaining broader and broader application in the foundry industry, among others for controlling melting processes in cupolas and in arc furnaces, for designing castings and supply systems, for controlling moulding sand processing, for predicting properties of cast alloys or selecting parameters of pressure castings. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. The presented investigations were obtained by using the Statistica 9.0 program. The aim of the investigations was to select the neural network suitable for prediction the moulding sand matrix grain size on the basis of the determined sand properties such as: permeability, compactibility, and compressive strength.

  10. Long-term Effects of Relative Humidity on Properties of Microwave Hardened Moulding Sand with Sodium Silicate

    Directory of Open Access Journals (Sweden)

    Stachowicz M.

    2017-09-01

    Full Text Available Moulding sands containing sodium silicate (water-glass belong to the group of porous mixture with low resistance to increased humidity. Thanks to hydrophilic properties of hardened or even overheated binder, possible is application of effective methods of hydrous reclamation consisting in its secondary hydration. For the same reason (hydrophilia of the binder, moulds and foundry cores made of high-silica moulding sands with sodium silicate are susceptible to the action of components of atmospheric air, including the contained steam. This paper presents results of a research on the effect of (relative humidity on mechanical and technological properties of microwave-hardened moulding mixtures. Specimens of the moulding sand containing 1.5 wt% of sodium water-glass with module 2.5 were subjected, in a laboratory climatic chamber, to long-term action of steam contained in the chamber atmosphere. Concentration of water in atmospheric air was stabilized for 28 days (672 h according to the relative humidity parameter that was ca. 40%, 60% and 80% at constant temperature 20 °C. In three cycles of the examinations, the specimens were taken out from the chamber every 7 days (168 h and their mechanical and technological parameters were determined. It was found on the grounds of laboratory measurements that moulds and cores hardened with microwaves are susceptible to action of atmospheric air and presence of water (as steam intensifies action of the air components on glassy film of sodium silicate. Microwave-hardened moulding sands containing sodium silicate may be stored on a long-term basis in strictly determined atmospheric conditions only, at reduced humidity. In spite of a negative effect of steam contained in the air, the examined moulding mixtures maintain a part of their mechanical and technological properties, so the moulds and foundry cores stored in specified, controlled conditions could be still used in manufacture.

  11. Effect of rheological parameters on curing rate during NBR injection molding

    Science.gov (United States)

    Kyas, Kamil; Stanek, Michal; Manas, David; Skrobak, Adam

    2013-04-01

    In this work, non-isothermal injection molding process for NBR rubber mixture considering Isayev-Deng curing kinetic model, generalized Newtonian model with Carreau-WLF viscosity was modeled by using finite element method in order to understand the effect of volume flow rate, index of non-Newtonian behavior and relaxation time on the temperature profile and curing rate. It was found that for specific geometry and processing conditions, increase in relaxation time or in the index of non-Newtonian behavior increases the curing rate due to viscous dissipation taking place at the flow domain walls.

  12. Effect of in-ovo injection of metformin on blood parameters and ...

    African Journals Online (AJOL)

    Blood parameters, including glucose, cholesterol, LDL (low density ... triglyceride, HDL, LDL and VLDL concentrations were significantly reduced by ... of Pharmaceutical Research is indexed by Science Citation Index (SciSearch), Scopus,.

  13. Warpage optimisation on the moulded part with straight-drilled and conformal cooling channels using response surface methodology (RSM) and glowworm swarm optimisation (GSO)

    Science.gov (United States)

    Hazwan, M. H. M.; Shayfull, Z.; Sharif, S.; Nasir, S. M.; Zainal, N.

    2017-09-01

    In injection moulding process, quality and productivity are notably important and must be controlled for each product type produced. Quality is measured as the extent of warpage of moulded parts while productivity is measured as a duration of moulding cycle time. To control the quality, many researchers have introduced various of optimisation approaches which have been proven enhanced the quality of the moulded part produced. In order to improve the productivity of injection moulding process, some of researches have proposed the application of conformal cooling channels which have been proven reduced the duration of moulding cycle time. Therefore, this paper presents an application of alternative optimisation approach which is Response Surface Methodology (RSM) with Glowworm Swarm Optimisation (GSO) on the moulded part with straight-drilled and conformal cooling channels mould. This study examined the warpage condition of the moulded parts before and after optimisation work applied for both cooling channels. A front panel housing have been selected as a specimen and the performance of proposed optimisation approach have been analysed on the conventional straight-drilled cooling channels compared to the Milled Groove Square Shape (MGSS) conformal cooling channels by simulation analysis using Autodesk Moldflow Insight (AMI) 2013. Based on the results, melt temperature is the most significant factor contribute to the warpage condition and warpage have optimised by 39.1% after optimisation for straight-drilled cooling channels and cooling time is the most significant factor contribute to the warpage condition and warpage have optimised by 38.7% after optimisation for MGSS conformal cooling channels. In addition, the finding shows that the application of optimisation work on the conformal cooling channels offers the better quality and productivity of the moulded part produced.

  14. Optimization of air injection parameters toward optimum fuel saving effect for ships

    Science.gov (United States)

    Lee, Inwon; Park, Seong Hyeon

    2016-11-01

    Air lubrication method is the most promising commercial strategy for the frictional drag reduction of ocean going vessels. Air bubbles are injected through the array of holes or the slots installed onto the flat bottom surface of vessel and a sufficient supply of air is required to ensure the formation of stable air layer by the by the coalescence of the bubbles. The air layer drag reduction becomes economically meaningful when the power gain through the drag reduction exceeds the pumping power consumption. In this study, a model ship of 50k medium range tanker is employed to investigate air lubrication method. The experiments were conducted in the 100m long towing tank facility at the Pusan National University. To create the effective air lubrication with lower air flow rate, various configurations including the layout of injection holes, employment of side fences and static trim have been tested. In the preliminary series of model tests, the maximum 18.13%(at 15kts) of reduction of model resistance was achieved. This research was supported by the National Research Foundation of Korea (NRF) Grant funded by the Korea government (MEST) through GCRC-SOP (Grant No. 2011-0030013).

  15. Investigation of over-moulded hybrid metal/polymer devices

    DEFF Research Database (Denmark)

    Tosello, Guido; Hansen, Hans Nørgaard; Tang, Peter Torben

    2006-01-01

    principles, in-process manufacturing technologies, as well as testing methodologies have to be established in order to be able to develop such integrated devices. In this paper an investigation of the bonding between miniaturized metal insert and a polymer matrix is presented. A special demonstrator...... was designed and manufactured by over-moulding and hot-embossing. The bonding strength between the insert and the plastic part was tested by means of a tensile test. A variety of parameters was studied in order to investigate their influence on the bonding: different polymeric and metallic materials, insert...

  16. A framework of cloud supported collaborative design in glass lens moulds based on aspheric measurement

    Science.gov (United States)

    Zhu, Yongjian; Wang, Yu; Na, Jingxin; Zhi, Yanan; Fan, Yufeng

    2013-09-01

    Aspheric mould design includes the top-down design and reversal design. In this paper, a new framework of reversal design is proposed combining with cloud supported collaborative design (CSCD) based on aspheric measurement. The framework is a kind of collaborative platform, which is composed of eight modules, including the computerized aspheric precision measurement module (CAPM), computer-aided optical design of aspheric lens system (CAOD), computer-aided design of lens mould (CADLM), FEM(finite element method) simulation of lens molding module (FEMLM), computer-aided manufacture of lens and moulds (CAMLM), measurement data analysis module (MDAM), optical product lifecycle management module (OPLM) and cloud computing network module (CCNM). In this framework, the remote clients send an improved requirement or fabrication demand about optical lens system through CCNM, which transfers this signal to OPLM. In OPLM, one main server is in charge of the task distribution and collaborative work of other six modules. The first measurement data of aspheric lens are produced by clients or our proposed platform CAPM, then are sent to CAOD for optimization and the electronic drawings of lens moulds are generated in CADLM module. According the design drawings, the FEMLM could give the lens-molding simulation parameters through FEM software. The simulation data are used for the second design of moulds in CADLM module. In this case, the moulds could be fabricated in CAMLM by ultra-precision machine, and the aspheric lens could be also produced by lens-molding machine in CAMLM. At last, the final shape of aspheric lens could be measured in CAPM and the data analysis could be conducted in MDAM module. Through the proposed framework, all the work described above could be performed coordinately. And the optimum design data of lens mould could be realized and saved, then shared by all the work team.

  17. Results of ionospheric parameters measurements during injections of exhaust streams of TSC "Progress" OMS

    Science.gov (United States)

    Khakhinov, Vitaly; Alsatkin, Sergey; Medvedev, Andrey; Kushnarev, Dmitriy; Lebedev, Valentin; Potekhin, Alexander; Ratovsky, Konstantin; Shpynev, Boris

    Since 2006 we have carried out active space experiments using the transport spacecraft (TSC) "Progress" and the ground-base Radio-Optic Complex of ISTP SB RAS including Irkutsk Incoherent Scatter Radar (IISR). Engine burns of TSC orbital maneuvering subsystem (OMS) were used as a source of ionospheric disturbances and changing radar signature characteristics of TSC. The flight altitudes were about 340 km. The amount of engine exhaust products was varied from 2 to 11 kg. The flow directions relative to IISR and amount of injected exhaust products were changed from flight to flight. The flows directed to IISR were almost parallel to the geomagnetic field line. For these cases the most pronounced effects were observed, the electron density depletion reached 20-40

  18. Development tendencies of moulding and core sands

    Directory of Open Access Journals (Sweden)

    Stanislaw M. Dobosz1

    2011-11-01

    Full Text Available Further development of the technology for making moulding and core sands will be strictly limited by tough requirements due to protection of the natural environment. These tendencies are becoming more and more tense, so that we will reach a point when even processes, that from technological point of view fulfill high requirements of the foundry industry, must be replaced by more ecologically-friendly solutions. Hence, technologies using synthetic resins as binding materials will be limited. This paper presents some predictable development tendencies of moulding and core sands. The increasing role of inorganic substances will be noticed, including silicate binders with significantly improved properties, such as improved knock-out property or higher reclamation strength. Other interesting solutions might also be moulding sands bonded by geo-polymers and phosphate binders or salts and also binders based on degradable biopolymers. These tendencies and the usefulness of these binders are put forward in this paper.

  19. Influence of Injection-Molding Process Parameters on Part Replication of Microstructures with Additively-Manufactured Soft Tooling Inserts WCMNM 2017 No

    DEFF Research Database (Denmark)

    Mischkot, Michael; Zhang, Yang; Segebrecht Gøtje, Asger

    The objective of this research is to investigate the influence of injection molding parameters on the dimensional replication of microstructure surfaces in injection molding with additively manufactured soft tooling inserts in a photopolymer material. The replication degree of micropillars...... diameter and decreases the replication degree of the pillar height. A high melt temperature increases the pillar diameter independently from the pillar height. A higher injection speed affects both pillar diameter and height negatively. In addition, the study showed a significant difference...

  20. Anti-stiction coating of PDMS moulds for rapid microchannel fabrication by double replica moulding

    DEFF Research Database (Denmark)

    Zhuang, Guisheng; Kutter, Jörg Peter

    2011-01-01

    ), which resulted in an anti-stiction layer for the improved release after PDMS casting. The deposition of FDTS on an O2 plasma-activated surface of PDMS produced a reproducible and well-performing anti-stiction monolayer of fluorocarbon, and we used the FDTS-coated moulds as micro-masters for rapid......In this paper, we report a simple and precise method to rapidly replicate master structures for fast microchannel fabrication by double replica moulding of polydimethylsiloxane (PDMS). A PDMS mould was surface-treated by vapour phase deposition of 1H,1H,2H,2H-perfluorodecyltrichlorosilane (FDTS...

  1. MouldingSandDB – a modern database storing moulding sands properties research results

    Directory of Open Access Journals (Sweden)

    J. Jakubski

    2011-01-01

    Full Text Available The complexity of foundry processes requires the use of modern, advanced IT tools for optimization, storage and analysis of t echnicaldata. Properties of moulding and core sands that are collected in research laboratories, manufacturers, and finally in the foundries, are not in use later on. It seems important to create a database that will allow to use the results stored, along with the possibility of searching according to set criteria, adjusted to casting practice. This paper presents part of the database named „MouldingSandDB”, which allows to collect and search data for synthetic moulding sands.

  2. CO2 injection into submarine, CH4-hydrate bearing sediments: Parameter studies towards the development of a hydrate conversion technology

    Science.gov (United States)

    Deusner, Christian; Bigalke, Nikolaus; Kossel, Elke; Haeckel, Matthias

    2013-04-01

    In the recent past, international research efforts towards exploitation of submarine and permafrost hydrate reservoirs have increased substantially. Until now, findings indicate that a combination of different technical means such as depressurization, thermal stimulation and chemical activation is the most promising approach for producing gas from natural hydrates. Moreover, emission neutral exploitation of CH4-hydrates could potentially be achieved in a combined process with CO2 injection and storage as CO2-hydrate. In the German gas hydrate initiative SUGAR, a combination of experimental and numerical studies is used to elucidate the process mechanisms and technical parameters on different scales. Experiments were carried out in the novel high-pressure flow-through system NESSI (Natural Environment Simulator for sub-Seafloor Interactions). Recent findings suggest that the injection of heated, supercritical CO2 is beneficial for both CH4 production and CO2 retention. Among the parameters tested so far are the CO2 injection regime (alternating vs. continuous injection) and the reservoir pressure / temperature conditions. Currently, the influence of CO2 injection temperature is investigated. It was shown that CH4 production is optimal at intermediate reservoir temperatures (8 ° C) compared to lower (2 ° C) and higher temperatures (10 ° C). The reservoir pressure, however, was of minor importance for the production efficiency. At 8 ° C, where CH4- and CO2-hydrates are thermodynamically stable, CO2-hydrate formation appears to be slow. Eventual clogging of fluid conduits due to CO2-rich hydrate formation force open new conduits, thereby tapping different regions inside the CH4-hydrate sample volume for CH4gas. In contrast, at 2 ° C immediate formation of CO2-hydrate results in rapid and irreversible obstruction of the entire pore space. At 10 ° C pure CO2-hydrates can no longer be formed. Consequently the injected CO2 flows through quickly and interaction with

  3. Experimental investigation of urea injection parameters influence on NOx emissions from blended biodiesel-fueled diesel engines.

    Science.gov (United States)

    Mehregan, Mina; Moghiman, Mohammad

    2018-02-01

    The present work submits an investigation about the effect of urea injection parameters on NO x emissions from a four-stroke four-cylinder diesel engine fueled with B20 blended biodiesel. An L 9 (3 4 ) Taguchi orthogonal array was used to design the test plan. The results reveal that increasing urea concentration leads to lower NO x emissions. Urea flow rate increment has the same influence on NO x emission. The same result is obtained by an increase in spray angle. Also, according to the analysis of variance (ANOVA), urea concentration and then urea flow rate are the most effective design parameters on NO x emissions, while spray angle and mixing length have less influence on this pollutant emission. Finally, since the result of confirmation test is in good agreement with the predicted value based on the Taguchi technique, the predictive capability of this method in the present study could be deduced.

  4. Biodegradable materials as binders for IVth generation moulding sands

    OpenAIRE

    K. Major-Gabry

    2015-01-01

    This paper focuses on the possibility of using the biodegradable materials as binders (or parts of binders?compositions) for foundry moulding and core sands. Results showed that there is a great possibility of using available biodegradable materials as foundry moulding sand binders. Using biodegradable materials as partial content of new binders, or additives to moulding sands may not only decrease the toxicity and increase reclamation ability of tested moulding sands, but also accelerate the...

  5. Determination of thermal conductivity in foundry mould mixtures

    Directory of Open Access Journals (Sweden)

    G. Solenički

    2010-01-01

    Full Text Available For a thorough understanding of the behaviour of foundry mould mixtures, a good knowledge of thermal properties of mould materials is needed. Laboratory determination of thermal conductivity of mould mixtures enables a better control over scabbing defects which are a major problem in green sand mould mixtures. A special instrument has been designed for that purpose and it is described in this work.

  6. Changes of gas pressure in sand mould during cast iron pouring

    Directory of Open Access Journals (Sweden)

    J. Mocek

    2011-10-01

    Full Text Available The paper presents a test method developed to measure changes of gas pressure in sand moulds during manufacture of iron castings. The pressure and temperature measurements were taken in the sand mould layers directly adjacent to the metal – mould interface. A test stand was described along with the measurement methodology. The sensors used allowed studying the fast-changing nature of the processes which give rise to the gas-originated casting defects. The study examined the influence of binders, clays and refining additives on the nature of the gas evolution process. The effect of the base sand type - quartz or olivine - on the nature of pressure changes was compared. The test stand design ensured the stability of technological parameters in the examined mould elements, and a repeatable process of making pilot castings. The main outcome was classification of sand mixtures in terms of pressure occurring during pouring of iron castings. The obtained results confirm the usefulness of the described method for testing gas pressure occurrence in a sand mould.

  7. Mould insert fabrication of a single-mode fibre connector alignment structure optimized by justified partial metallization

    International Nuclear Information System (INIS)

    Wissmann, Markus; Barié, Nicole; Guttmann, Markus; Schneider, Marc; Kolew, Alexander; Besser, Heino; Pfleging, Wilhelm; Hofmann, Andreas; Van Erps, Jürgen; Beri, Stefano; Watté, Jan

    2015-01-01

    For mass production of multiscale-optical components, microstructured moulding tools are needed. Metal tools are used for hot embossing or injection moulding of microcomponents made of a thermoplastic polymer. Microstructures with extremely tight specifications, e.g. low side wall roughness and high aspect ratios are generally made by lithographic procedures such as x-ray lithography or deep proton writing. However, these processes are unsuitable for low-cost mass production. An alternative manufacturing method of moulding tools has been developed at the Karlsruhe Institute of Technology (KIT). This article describes a mould insert fabrication and a new replication process for self-centring fibre alignment structures for low loss field installable single-mode fibre connectors, developed and fabricated by the Vrije Universiteit Brussel (VUB) in collaboration with TE Connectivity. These components are to be used in fibre-to-the-home networks and support the deployment and maintenance of fibre optic links. The special feature of this particular fibre connector is a self-centring fibre alignment, achieved by means of a through hole with deflectable cantilevers acting as micro-springs. The particular challenge is the electroforming of through holes with a centre hole diameter smaller than 125 µm. The fibre connector structure is prototyped by deep proton writing in polymethylmethacrylate and used as a sacrificial part. Using joining, physical vapour deposition and electroforming technology, a negative copy of the prototyped connector is transferred into nickel to be used as a moulding tool. The benefits of this replication technique are a rapid and economical fabrication of moulding tools with high-precision microstructures and a long tool life. With these moulding tools low-cost mass production is possible. We present the manufacturing chain we have established. Each individual manufacturing step of the mould insert fabrication will be shown in this report. The

  8. Gadolinium as a CT contrast agent: an experimental study for the effects of injection parameters in the rabbit brain model

    International Nuclear Information System (INIS)

    Kim, Hyun Jin; Choi, Hye Young; Lee, Sun Wha; Hwang, Ji Young

    2005-01-01

    We wanted to investigate the use of gadolinium based contrast agent (Gd-DTPA) for computed tomography (CT), and we also wanted to assess the effects of valuable injection parameters on enhancement in an experimental rabbit brain model. In vitro, attenuation measurements of serial dilutions of Gd-DTPA and iopromide were compared. In five rabbits, single level dynamic gadolinium-enhanced brain CT studies were obtained using different injection parameters. A comparision CT scan after iopromide administration was performed. The time-attenuation curves of the brain vessel and parenchyma were obtained and the magnitude of enhancement (Hmax) and the time to peak enhancement (Tmax) were analyzed. In vitro, the attenuation coefficient of undiluted Gd-DTPA (2,578 HU) was higher than that of iopromide (1,761 HU) at equimolar concentrations. In 5 rabbits, the time-attenuation curve demonstrated a distinct pattern with peak enhancement only in the brain vessel, but not in the brain parenchyma. There was increasing linear relationship between the injection rate of Gd-DTPA and Hmax, and a declining linear relationship with Tmax. The higher the concentration of Gd-DTPA, the higher Hmax was, but no significant difference was found for the Tmax. Higher volumes of Gd-DTPA revealed a higher Hmax and a delayed Tmax. Enhancement of the brain parenchyma on gadolinium-enhanced CT is minimal, while enhancement of the brain vessels is distinctive. The most important factor affecting Hmax of the vessel is the concentration of the contrast medium and the most important factor affecting Tmax of the vessel is volume of the contrast medium. The gadolinium-based contrast agent may be an reasonable alternative contrast agent for brain CT, and especially in cerebral vessels, and it may also be advantageous for brain parenchyma of those patients with BBB dysfunction

  9. Mycotoxigenic and proteolytic potential of moulds associated with ...

    African Journals Online (AJOL)

    Among the 33 moulds isolated from 20 samples of wood-smoked Chlamydoselachus anguincus (shark-fish) 20 isolates were capable of producing metabolites toxic to fertile Hubbard Golden Comet (Niger chick) eggs. Aspergillus and Pencillium isolates were the predominant moulds. Other toxigenic moulds isolated were ...

  10. ELECTROCHEMICAL TECHNOLOGIES FOR OBTAINING MOULDS FOR SOLES OF SHOES

    Directory of Open Access Journals (Sweden)

    Cornelia LUCA

    2013-05-01

    Full Text Available The paper presents contributions in the designing of some electrochemical technologiesfor the manufacturing of the moulds used in the footwear soles obtaining. There are presented a fewmethods for the moulds obtaining, using electro-deposit processes. There are presented thetechnological phases of the obtaining process of the electrolytes and electrodes preparing and thetechnological stages of the moulds manufacturing.

  11. Shape Accuracy of Iron Precision Castings in Terms of Ceramic Moulds Physical Properties Anisotropy

    Directory of Open Access Journals (Sweden)

    Biernacki R.

    2014-03-01

    Full Text Available While analyzing shape accuracy of ferroalloy precision castings in terms of ceramic moulds physical anisotropy, low-alloy steel castings ("cover" and cast iron ("plate" were included. The basic parameters in addition to the product linear shape accuracy are flatness deviations, especially due to the expanded flat surface which is cast plate. For mentioned castings surface micro-geometry analysis was also carried, favoring surface load capacity tp50 for Rmax = 50%. Surface load capacity tp50 obtained for the cast cover was compared with machined product, and casting plate surface was compared with wear part of the conveyor belt. The results were referred to anisotropy of ceramic moulds physical properties, which was evaluated by studying ceramic moulds samples in computer tomography equipment Metrotom 800

  12. Tactile and visual perception of injection moulded plastic parts

    DEFF Research Database (Denmark)

    Jensen, Jacob Tobias; Akbas, Erkan; Madsen, Mads

    In today’s world the technical development have reached high levels in many products. This means that the technical specifications are not as high a competition factor as it has been. Therefore the visual appeal (aesthetics) and tactile perception (ergonomics) have become much more important in t...... in a number of ways including measuring of surface roughness, contact angle, gloss measurement and human perception....

  13. Micro powder-injection moulding of metals and ceramics

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    Development of micro-MIM/-CIM was started at Forschungszen- ... of microsystems products not only possesses a respectable market poten- .... We gratefully acknowledge the financial support of the Deutsche Forschungsgemeinschaft.

  14. Injection moulding and selective metallisation technologies for polymer Microsystems

    DEFF Research Database (Denmark)

    Tenchine, L.; Gout, S.; Dessors, S.

    2016-01-01

    The present paper describes how developing and optimizing high-throughput integrated technologies for theproduction of miniaturised multi-material and multi-functional components at industrial scale. Based on 2 industrialdemonstrators (a band diplexer and a micro aeraulic device), the paper shows...

  15. Micro powder-injection moulding of metals and ceramics

    Indian Academy of Sciences (India)

    Development of micro-MIM/-CIM was started at Forschungszentrum Karlsruhe with the aim of creating a process suitable for a wide range of materials as well as for medium-scale and large-scale production of micro components. Using enhanced machine technology and special tempering procedures, this process enables ...

  16. Influence of process parameters on the weld lines of a micro injection molded component

    DEFF Research Database (Denmark)

    Tosello, Guido; Gava, Alberto; Hansen, Hans Nørgaard

    2007-01-01

    The insufficient entanglement of the molecular chains and the stress amplification at the v-notch of a weld line compromise the mechanical strength of a plastic product, also in the micro scale. To investigate the influence of process parameters on the weld lines formation, a special micro cavity...... was designed and manufactured by µEDM (Electro Discharge Machining). Weld lines were quantitatively characterized both in the two-dimensional (direction and position) and three-dimensional range (surface topography characterization). Results showed that shape and position of weld lines are mainly influenced...

  17. Effect of pressure in mould on the mould cavity filling in Lost Foam process

    Directory of Open Access Journals (Sweden)

    T. Pacyniak

    2010-10-01

    Full Text Available In this study, the analysis of the influence of the pressure in mould on manufacture process of castings by the Lost Foam method wasintroduced. In particular, numerical simulation results of effect of pressure in mould on pouring rate, gas gap pressure and gas gap sizewere analyzed. For simulating investigations of the Lost Foam process introduced mathematical model of the process was used. In thismodel in detail was described and derived equation relating to the changes of the gas pressure in the gas gap. The mathematical description uses the equation of gas state and the equation of Darcy’s rate of filtration. Presented studies indicated, that with decrease of pressure in mould the pouring rate increased and the gas pressure in gas gap and gas gap size decreased. For pressures in mould from the range of 20÷100 kPa, pouring rates achieved values from 30÷3 cm/s respectively.

  18. Geometric accuracy of wax bade models manufactured in silicon moulds

    Directory of Open Access Journals (Sweden)

    G. Budzik

    2010-01-01

    Full Text Available The article presents the test results of the geometric accuracy of wax blade models manufactured in silicon moulds in the Rapid Tooling process, with the application of the Vacuum Casting technology. In batch production casting waxes are designed for the manufacture of models and components of model sets through injection into a metal die. The objective of the tests was to determine the possibility of using traditional wax for the production of casting models in the rapid prototyping process. Blade models made of five types of casting wax were measured. The definition of the geometric accuracy of wax blade models makes it possible to introduce individual modifications aimed at improving their shape in order to increase the dimensional accuracy of blade models manufactured in the rapid prototyping process.

  19. Wood Flour Moulding Technology: Implications for Technical ...

    African Journals Online (AJOL)

    User

    2011-04-19

    Apr 19, 2011 ... be waste product from saw mills, wood working plants or produced from selected dry wood by .... Stop watch-used to indicate the exact time the mould has remained in the press before wood .... There is abundance of saw dust the source of which is the ... Madison, Wisconsin: Wiley Interscience. Usoro, H. S. ...

  20. Flexible Mould for Precast Concrete Elements

    DEFF Research Database (Denmark)

    Jepsen, Christian Raun; Kristensen, Mathias Kræmmergaard; Kirkegaard, Poul Henning

    2010-01-01

    The present paper describes the development of a digitally controlled mou Id that forms a double curved and fair surface directly from the digital CAD model. The primary motivation for the development of the mould is to reduce the cost of constructing double curved, cast elements for architecture...

  1. Wood Flour Moulding Technology: Implications for Technical ...

    African Journals Online (AJOL)

    The intent of this article is to demonstrate how wood waste called sawdust or wood flour can be transformed by plastic moulding machine into items of economic value. Wood flour is wood reduced to very fine particle form. It can be waste product from saw mills, wood working plants or produced from selected dry wood by ...

  2. On the Injection Molding Processing Parameters of HDPE-TiO2 Nanocomposites

    Science.gov (United States)

    Mourad, Abdel-Hamid I.; Mozumder, Mohammad Sayem; Mairpady, Anusha; Pervez, Hifsa; Kannuri, Uma Maheshwara

    2017-01-01

    In recent years, the development and use of polymeric nanocomposites in creating advanced materials has expanded exponentially. A substantial amount of research has been done in order to design polymeric nanocomposites in a safe and efficient manner. In the present study, the impact of processing parameters, such as, barrel temperature, and residence time on the mechanical and thermal properties of high density polyethylene (HDPE)-TiO2 nanocomposites were investigated. Additionally, scanning electron microscopy and X-ray diffraction spectroscopy were used to analyze the dispersion, location, and phase morphology of TiO2 on the HDPE matrix. Mechanical tests revealed that tensile strength of the fabricated HDPE-TiO2 nanocomposites ranged between 22.53 and 26.30 MPa, while the Young’s modulus showed a consistent increase as the barrel temperature increased from 150 °C to 300 °C. Moreover, the thermal stability decreased as the barrel temperature increased. PMID:28772444

  3. On the Injection Molding Processing Parameters of HDPE-TiO₂ Nanocomposites.

    Science.gov (United States)

    Mourad, Abdel-Hamid I; Mozumder, Mohammad Sayem; Mairpady, Anusha; Pervez, Hifsa; Kannuri, Uma Maheshwara

    2017-01-20

    In recent years, the development and use of polymeric nanocomposites in creating advanced materials has expanded exponentially. A substantial amount of research has been done in order to design polymeric nanocomposites in a safe and efficient manner. In the present study, the impact of processing parameters, such as, barrel temperature, and residence time on the mechanical and thermal properties of high density polyethylene (HDPE)-TiO₂ nanocomposites were investigated. Additionally, scanning electron microscopy and X-ray diffraction spectroscopy were used to analyze the dispersion, location, and phase morphology of TiO₂ on the HDPE matrix. Mechanical tests revealed that tensile strength of the fabricated HDPE-TiO₂ nanocomposites ranged between 22.53 and 26.30 MPa, while the Young's modulus showed a consistent increase as the barrel temperature increased from 150 °C to 300 °C. Moreover, the thermal stability decreased as the barrel temperature increased.

  4. The influence of particle size distribution on the properties of metalinjection-moulded 17-4 PH stainless steel

    CSIR Research Space (South Africa)

    Seerane, Mandy

    2016-10-01

    Full Text Available Metal injection moulding (MIM) is a near-net-shaping powder metallurgy technique suitable for the cost-effective mass production of small and complex components. In this paper, the effects of the metal powder particle size on the final properties...

  5. Mathematical model of the metal mould surface temperature optimization

    Energy Technology Data Exchange (ETDEWEB)

    Mlynek, Jaroslav, E-mail: jaroslav.mlynek@tul.cz; Knobloch, Roman, E-mail: roman.knobloch@tul.cz [Department of Mathematics, FP Technical University of Liberec, Studentska 2, 461 17 Liberec, The Czech Republic (Czech Republic); Srb, Radek, E-mail: radek.srb@tul.cz [Institute of Mechatronics and Computer Engineering Technical University of Liberec, Studentska 2, 461 17 Liberec, The Czech Republic (Czech Republic)

    2015-11-30

    The article is focused on the problem of generating a uniform temperature field on the inner surface of shell metal moulds. Such moulds are used e.g. in the automotive industry for artificial leather production. To produce artificial leather with uniform surface structure and colour shade the temperature on the inner surface of the mould has to be as homogeneous as possible. The heating of the mould is realized by infrared heaters located above the outer mould surface. The conceived mathematical model allows us to optimize the locations of infrared heaters over the mould, so that approximately uniform heat radiation intensity is generated. A version of differential evolution algorithm programmed in Matlab development environment was created by the authors for the optimization process. For temperate calculations software system ANSYS was used. A practical example of optimization of heaters locations and calculation of the temperature of the mould is included at the end of the article.

  6. Mathematical model of the metal mould surface temperature optimization

    International Nuclear Information System (INIS)

    Mlynek, Jaroslav; Knobloch, Roman; Srb, Radek

    2015-01-01

    The article is focused on the problem of generating a uniform temperature field on the inner surface of shell metal moulds. Such moulds are used e.g. in the automotive industry for artificial leather production. To produce artificial leather with uniform surface structure and colour shade the temperature on the inner surface of the mould has to be as homogeneous as possible. The heating of the mould is realized by infrared heaters located above the outer mould surface. The conceived mathematical model allows us to optimize the locations of infrared heaters over the mould, so that approximately uniform heat radiation intensity is generated. A version of differential evolution algorithm programmed in Matlab development environment was created by the authors for the optimization process. For temperate calculations software system ANSYS was used. A practical example of optimization of heaters locations and calculation of the temperature of the mould is included at the end of the article

  7. The effect of internal mould water spray cooling on rotationally moulded polyethylene parts

    Science.gov (United States)

    McCourt, Mark P.; Kearns, Mark P.; Martin, Peter J.

    2018-05-01

    The conventional method of cooling during the rotational moulding process is through the use of forced air. During the cooling phase of a typical rotomoulding cycle, large volumes of high velocity room temperature air are forced across the outside of the rotating rotomoulding tool to encourage cooling of the metal mould and molten polymer. Since no cooling is applied to the inside of the mould, the inner surface of the polymer (polyethylene) cools more slowly and will have a tendency to be more crystalline and the polyethylene will have a higher density in this region. The side that cools more quickly (in contact with the inside mould wall) will be less crystalline, and will therefore have a lower density. The major consequence of this difference in crystallinity will be a buildup of internal stresses producing warpage and excessive shrinkage of the part with subsequent increased levels of scrap. Therefore excessive cooling on the outside of the mould should be avoided. One consequence of this effect is that the cooling time for a standard rotationally moulded part can be quite long and this has an effect on the overall economics of the process in terms of part manufacture. A number of devices are currently on the market to enhance the cooling of rotational moulding by introducing a water spray to the inside of the rotomoulding during cooling. This paper reports on one such device 'Rotocooler' which during a series of initial industrial trials has been shown to reduce the cycletime by approximately 12 to 16%, with minimal effect on the mechanical properties, leading to a part which has less warpage and shrinkage than a conventionally cooled part.

  8. A Comparative Analysis of Taguchi Methodology and Shainin System DoE in the Optimization of Injection Molding Process Parameters

    Science.gov (United States)

    Khavekar, Rajendra; Vasudevan, Hari, Dr.; Modi, Bhavik

    2017-08-01

    Two well-known Design of Experiments (DoE) methodologies, such as Taguchi Methods (TM) and Shainin Systems (SS) are compared and analyzed in this study through their implementation in a plastic injection molding unit. Experiments were performed at a perfume bottle cap manufacturing company (made by acrylic material) using TM and SS to find out the root cause of defects and to optimize the process parameters for minimum rejection. Experiments obtained the rejection rate to be 8.57% from 40% (appx.) during trial runs, which is quiet low, representing successful implementation of these DoE methods. The comparison showed that both methodologies gave same set of variables as critical for defect reduction, but with change in their significance order. Also, Taguchi methods require more number of experiments and consume more time compared to the Shainin System. Shainin system is less complicated and is easy to implement, whereas Taguchi methods is statistically more reliable for optimization of process parameters. Finally, experimentations implied that DoE methods are strong and reliable in implementation, as organizations attempt to improve the quality through optimization.

  9. [Invasive mould disease in haematological patients].

    Science.gov (United States)

    Ruiz-Camps, Isabel; Jarque, Isidro

    2014-01-01

    Invasive mould infections (IMI) are a persistent problem with high morbidity and mortality rates among patients receiving chemotherapy for hematological malignancies and hematopoietic stem cell transplant recipients. Management of IMI in this setting has become increasingly complex with the advent of new antifungal agents and diagnostic tests, which have resulted in different therapeutic strategies (prophylactic, empirical, pre-emptive, and directed). A proper assessment of the individual risk for IMI appears to be critical in order to use the best prophylactic and therapeutic approach and increase the survival rates. Among the available antifungal drugs, the most frequently used in the hematologic patient are fluconazole, mould-active azoles (itraconazole, posaconazole and voriconazole), candins (anidulafungin, caspofungin and micafungin), and lipid formulations of amphotericin B. Specific recommendations for their use, and criteria for selecting the antifungal agents are discussed in this paper. Copyright © 2014. Published by Elsevier Espana.

  10. Acute effects of anesthetic lumbar spine injections on temporal spatial parameters of gait in individuals with chronic low back pain: A pilot study.

    Science.gov (United States)

    Herndon, Carl L; Horodyski, MaryBeth; Vincent, Heather K

    2017-10-01

    This study examined whether epidural injection-induced anesthesia acutely and positively affected temporal spatial parameters of gait in patients with chronic low back pain (LBP) due to lumbar spinal stenosis. Twenty-five patients (61.7±13.6years) who were obtaining lumbar epidural injections for stenosis-related LBP participated. Oswestry Disability Index (ODI) scores, Medical Outcomes Short Form (SF-36) scores, 11-point Numerical pain rating (NRS pain ) scores, and temporal spatial parameters of walking gait were obtained prior to, and 11-point Numerical pain rating (NRS pain ) scores, and temporal spatial parameters of walking gait were obtained after the injection. Gait parameters were measured using an instrumented gait mat. Patients received transforaminal epidural injections in the L1-S1 vertebral range (1% lidocaine, corticosteroid) under fluoroscopic guidance. Patients with post-injection NRS pain ratings of "0" or values greater than "0" were stratified into two groups: 1) full pain relief, or 2) partial pain relief, respectively. Post-injection, 48% (N=12) of patients reported full pain relief. ODI scores were higher in patients with full pain relief (55.3±21.4 versus 33.7 12.8; p=0.008). Post-injection, stride length and step length variability were significantly improved in the patients with full pain relief compared to those with partial pain relief. Effect sizes between full and partial pain relief for walking velocity, step length, swing time, stride and step length variability were medium to large (Cohen's d>0.50). Patients with LBP can gain immediate gait improvements from complete pain relief from transforaminal epidural anesthetic injections for LBP, which could translate to better stability and lower fall risk. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Experimental investigation of the effects of direct water injection parameters on engine performance in a six-stroke engine

    International Nuclear Information System (INIS)

    Arabaci, Emre; İçingür, Yakup; Solmaz, Hamit; Uyumaz, Ahmet; Yilmaz, Emre

    2015-01-01

    Highlights: • Exhaust gas temperature and specific fuel consumption decreased with six stroke engine. • Thermal efficiency increased with water injection. • NO emissions decreased with water injection as the temperature decreased at the end of cycle. • Injection timing should be advanced with the increase of engine speed. • HC and CO emissions decrease until 3000 rpm engine speed. - Abstract: In this study, the effects of water injection quantity and injection timing were investigated on engine performance and exhaust emissions in a six-stroke engine. For this purpose, a single cylinder, four-stroke gasoline engine was converted to six-stroke engine modifying a new cam mechanism and adapting the water injection system. The experiments were conducted at stoichometric air/fuel ratio (λ = 1) between 2250 and 3500 rpm engine speed at full load with liquid petroleum gas. Water injection was performed at three different stages as before top dead center, top dead center and after top dead center at constant injection duration and four different injection pressure 25, 50, 75 and 100 bar. The test results showed that exhaust gas temperature and specific fuel consumption decreased by about 7% and 9% respectively. In contrast, fuel consumption and power output increased 2% and 10% respectively with water injection. Thermal efficiency increased by about 8.72% with water injection. CO and HC emissions decreased 21.97% and 18.23% until 3000 rpm respectively. NO emissions decreased with water injection as the temperature decreased at the end of cycle. As a result, it was seen that engine performance improved when suitable injection timing and injected water quantity were selected due to effect of exhaust heat recovery with water injection

  12. Optimisation of process parameters on thin shell part using response surface methodology (RSM) and genetic algorithm (GA)

    Science.gov (United States)

    Faiz, J. M.; Shayfull, Z.; Nasir, S. M.; Fathullah, M.; Hazwan, M. H. M.

    2017-09-01

    This study conducts the simulation on optimisation of injection moulding process parameters using Autodesk Moldflow Insight (AMI) software. This study has applied some process parameters which are melt temperature, mould temperature, packing pressure, and cooling time in order to analyse the warpage value of the part. Besides, a part has been selected to be studied which made of Polypropylene (PP). The combination of the process parameters is analysed using Analysis of Variance (ANOVA) and the optimised value is obtained using Response Surface Methodology (RSM). The RSM as well as Genetic Algorithm are applied in Design Expert software in order to minimise the warpage value. The outcome of this study shows that the warpage value improved by using RSM and GA.

  13. A characteristic of design solutions for flask moulding lines

    OpenAIRE

    Fedoryszyn, A.

    2007-01-01

    Moulding machines used in manufacture of moulds from synthetic bentonite sands constitute basic equipment of mechanised stands, work centres, and production lines. In the present article, a short characteristic of this equipment was given, basing on the generally accepted criteria of classification taking into consideration novel design solutions and principles of cooperation between individual sub-assemblies. Moulding equipment offered by domestic producers was described with emphasis put on...

  14. Clinical analyses of successful and previously failed intracytoplasmic sperm injection cycle parameters in patients with poor ovarian reserve

    Directory of Open Access Journals (Sweden)

    Tayfun Kutlu

    2017-03-01

    Full Text Available Objective: To determine some major characteristic differences between two consecutive successful and unsuccessful intracytoplasmic sperm injection (ICSI cycles in poor responders. Materials and Methods: Sixty women with poor ovarian response as determined using the Bologna criteria underwent ICSI cycles following an unsuccessful trial. Some parameters of both cycles including age, body mass index (BMI, serum follicle-stimulating hormone (FSH and estradiol levels, antral follicle count, gonadotropin dosage, duration of stimulation, antagonist starting day, duration of antagonist administration, endometrial thickness at trigger day, number of total and fertilized oocytes, embryo transfer day, number of embryo cells, and fertilization rate were compared in the same patients to identify predictors of cycles with clinical pregnancy. Results: The mean age, BMI, serum FSH, estradiol concentrations, and antral follicle count were 35.9 years (range, 30-42 years, 25.9 kg/m2 (range, 18.4-33.5 kg/m2, 10.9 IU/mL (range, 7-13 IU/mL, 52.9 pg/mL (range, 11.6-75 pg/mL, and 4.7 (range, 2-10, respectively. A comparison of cycle characteristics showed a significantly higher total number of mature and fertilized oocytes in successful cycles. The fertilization rate was also significantly higher in cycles with clinical pregnancy. Early initiation of antagonist was shown to result in favorable outcomes. A comparison of embryo characteristics showed that transfer of higher-stage embryos and embryos with higher numbers of cells had a significant impact on cycle outcomes. Conclusion: Our comparison of parameters of failed and successful ICSI cycles in poor responders revealed significantly earlier antagonist initiation, higher total number of mature and fertilized oocytes, fertilization rate, and significantly higher stage of embryo development and cell numbers at transfer in cycles that resulted in clinical pregnancy.

  15. Presence of moulds and mycotoxins in spices

    Directory of Open Access Journals (Sweden)

    Karan Dragica D.

    2005-01-01

    Full Text Available In this paper there are presented the results of mycologic and mycotoxicologic analysis of seven spices which are being used for production of meat products. Using standard mycologic methods, in all the tested samples, we noticed a presence of moulds. By quality and quantity, most represented are genera: Aspergillus and Penicillium. With smaller occurrence there are presented genera: Rhizopus, Mucor, Paecylomyces and Absydia. Mycotoxins - ochratoxin, aflatoxins and zearalenon, are detected in samples of ground white pepper, ginger, cloves and ground caraway.

  16. Single peak parameters technique for simultaneous measurements: Spectrophotometric sequential injection determination of Fe(II) and Fe(III).

    Science.gov (United States)

    Kozak, J; Paluch, J; Węgrzecka, A; Kozak, M; Wieczorek, M; Kochana, J; Kościelniak, P

    2016-02-01

    Spectrophotometric sequential injection system (SI) is proposed to automate the method of simultaneous determination of Fe(II) and Fe(III) on the basis of parameters of a single peak. In the developed SI system, sample and mixture of reagents (1,10-phenanthroline and sulfosalicylic acid) are introduced into a vessel, where in an acid environment (pH≅3) appropriate compounds of Fe(II) and Fe(III) with 1,10-phenanthroline and sulfosalicylic acid are formed, respectively. Then, in turn, air, sample, EDTA and sample again, are introduced into a holding coil. After the flow reversal, a segment of air is removed from the system by an additional valve and as EDTA replaces sulfosalicylic acid forming a more stable colorless compound with Fe(III), a complex signal is registered. Measurements are performed at wavelength 530 nm. The absorbance measured at minimum of the negative peak and the area or the absorbance measured at maximum of the signal can be used as measures corresponding to Fe(II) and Fe(III) concentrations, respectively. The time of the peak registration is about 2 min. Two-component calibration has been applied to analysis. Fe(II) and Fe(III) can be determined within the concentration ranges of 0.04-4.00 and 0.1-5.00 mg L(-1), with precision less than 2.8% and 1.7% (RSD), respectively and accuracy better than 7% (RE). The detection limit is 0.04 and 0.09 mg L(-1) for Fe(II) and Fe(III), respectively. The method was applied to analysis of artesian water samples. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Sampling And Identifying Of Mould In The Library Building

    Directory of Open Access Journals (Sweden)

    Abdul Wahab Suriani Ngah

    2016-01-01

    Full Text Available Despite the growing concern over mould and fungi infestations on library building, little has been reported in the literature on the development of an objective tool and criteria for measuring and characterising the mould and fungi. In this paper, an objective based approach to mould and fungi growth assessment using various sampling techniques and its identification using microscopic observation are proposed. This study involved three library buildings of Higher Institution Educational in Malaysia for data collection purpose and study of mould growth. The mould sampling of three libraries was collected using Coriolis air sampler, settling plate air sampling using Malt Extract Agar (MEA, IAQ MOLD Alexeter IAQ-Pro Asp/Pen® Test and swab sampling techniques. The IAQ MOLD Alexeter IAQ-Pro Asp/Pen® Test and traditional method technique identified various mould species immediately on the site, and the microscopic observation identifies common types of the mould such as Aspergillus, Penicillium and Stachybotrys’s. The sample size and particular characteristics of each library will result in the mould growth pattern and finding.

  18. Advances in precision machining and moulding technology bring design opportunities.

    Science.gov (United States)

    Glendening, Paul

    2008-09-01

    Machining of materials for medical applications has moved to a new level of precision. In parallel with this, moulding technology has improved through the increased use of sensors in moulds, enhanced design simulation and processes such as micromoulding. This article examines the opportunities offered by these developments and includes examples of mass produced parts that demonstrate the new capabilities useful to product designers.

  19. Characterization of moulds associated with processed garri stored ...

    African Journals Online (AJOL)

    Characterization of moulds associated with processed white and yellow garri stored at ambient temperature for 40 days was investigated. The moulds isolated from white garri (%) were: Aspergillus spp 35.3, Penicillium spp 23.53, Fusarium spp 2.94, Mucor spp 17.65, Alternaria spp 5.88, Cladosporium sp 2.94 and ...

  20. Modeling and Optimization of Phenol Formaldehyde Resin Sand Mould System

    Directory of Open Access Journals (Sweden)

    Chate G. R.

    2017-06-01

    Full Text Available Chemical bonded resin sand mould system has high dimensional accuracy, surface finish and sand mould properties compared to green sand mould system. The mould cavity prepared under chemical bonded sand mould system must produce sufficient permeability and hardness to withstand sand drop while pouring molten metal through ladle. The demand for improved values of permeability and mould hardness depends on systematic study and analysis of influencing variables namely grain fineness number, setting time, percent of resin and hardener. Try-error experiment methods and analysis were considered impractical in actual foundry practice due to the associated cost. Experimental matrices of central composite design allow conducting minimum experiments that provide complete insight of the process. Statistical significance of influencing variables and their interaction were determined to control the process. Analysis of variance (ANOVA test was conducted to validate the model statistically. Mathematical equation was derived separately for mould hardness and permeability, which are expressed as a non-linear function of input variables based on the collected experimental input-output data. The developed model prediction accuracy for practical usefulness was tested with 10 random experimental conditions. The decision variables for higher mould hardness and permeability were determined using desirability function approach. The prediction results were found to be consistent with experimental values.

  1. Investigation of field temperature in moulds of foamed plaster

    Directory of Open Access Journals (Sweden)

    M. Pawlak

    2007-12-01

    Full Text Available Plaster moulds used in precision foundry are characterized by a very low permeability which, in the case of classic plaster moulds, equals to about 0,01÷0,02 m2/(MPa·s. One of the most effective methods for increasing the permeability is a foaming treatment. Another characteristic feature of plaster is its very good insulating power which has influence on the process of solidification and cooling of a cast and also on a knock-out property. This insulating power is a function of thermophysical properties of plaster which, in turn, depend mainly on the mineralogical composition of the mould material, its bulk density as well as on the temperature of the pouring alloy. In the case of a foamed plaster mould an increase of the degree of foaming increases its porosity which causes a change in its thermophysical properties, thereby increasing susceptibility of the mass to overheating. The susceptibility of the plaster layer surrounding the cast to overheating is favorable because it makes it easier to knock-out of the cast by immersing the hot mould in cold water. Thermal and phase tensions that are created during this process cause fast destruction of plaster. This paper describes our investigations aimed at the determination of the dependence of the mould temperature field on the time of the cast stay in the mould, as recorded in a process of an unsteady heat flow. The determined data were planned to be used for estimation of the technological properties of the plaster mould. The tests were carried out using the plaster α-Supraduro and Alkanol XC (foaming agent. The test mould had a diameter of Ø 120 mm with centrally situated mould cavity of Ø 30 mm. Plaster moulds with a degree of foaming 20; 32,5 and 45% and comparatively from non-foaming plaster were tested and their temperatures were measured at the distance x=2; 9; 21; 25;27; 30 mm from the mould cavity within 25 min. Analysis of the results leads to the conclusion, that the highest

  2. Advances in Physarum machines sensing and computing with Slime mould

    CERN Document Server

    2016-01-01

    This book is devoted to Slime mould Physarum polycephalum, which is a large single cell capable for distributed sensing, concurrent information processing, parallel computation and decentralized actuation. The ease of culturing and experimenting with Physarum makes this slime mould an ideal substrate for real-world implementations of unconventional sensing and computing devices The book is a treatise of theoretical and experimental laboratory studies on sensing and computing properties of slime mould, and on the development of mathematical and logical theories of Physarum behavior. It is shown how to make logical gates and circuits, electronic devices (memristors, diodes, transistors, wires, chemical and tactile sensors) with the slime mould. The book demonstrates how to modify properties of Physarum computing circuits with functional nano-particles and polymers, to interface the slime mould with field-programmable arrays, and to use Physarum as a controller of microbial fuel cells. A unique multi-agent model...

  3. Influence of the Training Set Value on the Quality of the Neural Network to Identify Selected Moulding Sand Properties

    Directory of Open Access Journals (Sweden)

    Jakubski J.

    2013-06-01

    Full Text Available Artificial neural networks are one of the modern methods of the production optimisation. An attempt to apply neural networks for controlling the quality of bentonite moulding sands is presented in this paper. This is the assessment method of sands suitability by means of detecting correlations between their individual parameters. This paper presents the next part of the study on usefulness of artificial neural networks to support rebonding of green moulding sand, using chosen properties of moulding sands, which can be determined fast. The effect of changes in the training set quantity on the quality of the network is presented in this article. It has been shown that a small change in the data set would change the quality of the network, and may also make it necessary to change the type of network in order to obtain good results.

  4. Simulation of Air Entrapment and Resin Curing During Manufacturing of Composite Cab Front by Resin Transfer Moulding Process

    Directory of Open Access Journals (Sweden)

    Kuppusamy Raghu Raja Pandiyan

    2017-09-01

    Full Text Available Mould filling and subsequent curing are the significant processing stages involved in the production of a composite component through Resin Transfer Moulding (RTM fabrication technique. Dry spot formation and air entrapment during filling stage caused by improper design of filling conditions and locations that lead to undesired filling patterns resulting in defective RTM parts. Proper placement of inlet ports and exit vents as well as by adjustment of filling conditions can alleviate the problems during the mould filling stage. The temperature profile used to polymerize the resin must be carefully chosen to reduce the cure time. Instead of trial and error methods that are expensive, time consuming, and non-optimal, we propose a simulation-based optimization strategy for a composite cab front component to reduce the air entrapment and cure stage optimization. In order to be effective, the optimization strategy requires an accurate simulation of the process utilizing submodels to describe the raw material characteristics. Cure reaction kinetics and chemo-rheology were the submodels developed empirically for an unsaturated polyester resin using experimental data. The simulations were performed using commercial software PAM RTM 2008, developed by ESI Technologies. Simulation results show that the use of increase in injection pressure at the inlet filling conditions greatly reduce the air entrapped. For the cab front, the alteration of injection pressure with proper timing of vent opening reduced the air entrapped during mould filling stage. Similarly, the curing simulation results show that the use of higher mould temperatures effectively decreases the cure time as expected.

  5. Effects of Ascorbic Acid Injection in Incubated Eggs Submitted to Heat Stress on Incubation Parameters and Chick Quality

    Directory of Open Access Journals (Sweden)

    S Sgavioli

    2015-06-01

    Full Text Available Dose-dependent positive effects on hatchability and hatchling weight have been attributed to ascorbic acid (AA when eggs were submitted or not to intermittent heat stress during incubation. Fertile breeder (Cobb(r eggs were used to determine if the pre-incubation injection of AA in ovo affects the incubation and hatchling quality of egg incubated under thermoneutral or intermittent heat stress conditions. Eggs were not injected or injected with 0, 2,4, or 6% AA/100µL water and incubated at continuous thermoneutral (37.5ºC or hot (39.0ºC temperature. Eggshell temperature (EST increased in the second half of the incubation period in all experimental groups. The EST of non-injected eggs and of those injected with water was higher when incubated at 39°C than at 37.5°C, but EST was not different among eggs injected with AA. Egg mass loss and eggshell conductance were higher in the eggs incubated at 39°C than at 37.5°C.Hatchability was lower in the eggs injected with AA. Liver and yolk sac weights were higher, whereas heart and liver weights were lower in hatchlings from eggs incubated at 39°C; however, hatchling weight was not affected by incubation temperature. The results showed that AA doses affected egg conductive heat loss and hatchability, and that they did not minimize the effects of high incubation temperature on liver and heart development.

  6. Effect of bentonite addition on residual strength of microwave-hardened waterglass-containing moulding sands

    Directory of Open Access Journals (Sweden)

    M. Stachowicz

    2011-07-01

    Full Text Available The paper presents results of a preliminary research of the effect of bentonite addition on residual strength of microwave-hardened moulding sands, containing sodium waterglass. Strength was determined at ambient temperature, on cylindrical specimens baked in an oven. Moulding sands for examinations were based on high-silica sand with addition of 2.5 % of non-modified, domestic-made waterglass grade 145. The prepared standard cylindrical specimens were hardened using the innovative microwave heating process and next baked for 30 minutes at temperatures between 100 and 1200 °C. Strength parameters of the specimens were determined on the specimens cooled- down to ambient temperature. The obtained results were compared with literature data to evaluate the effect of the applied hardening method and of the special additive on residual strength as a function of baking temperature. A favourable effect was found of both the innovative heating process and the applied bentonite addition.

  7. Numerical modelling of thermal and fluid flow phenomena in the mould channel

    Directory of Open Access Journals (Sweden)

    L. Sowa

    2007-12-01

    Full Text Available In the paper, a mathematical and a numerical model of the solidification of a cylindrical slender shaped casting, which take into account the process of filling the mould cavity with molten metal, has been proposed. Pressure and velocity fields were obtained by solving the momentum equations and the continuity equation, while the thermal fields were obtained by solving the heat conduction equation containing the convection term. Next, the numerical analysis of the solidification process of metals alloy in a cylindrical mould channel has been made. In the model one takes into account interdependence the heat transfer and fluid flow phenomena. Coupling of the thermal and fluid flow phenomena has been taken into consideration by the changes of the fluidity function and thermophysical parameters of alloy with respect to the temperature. The influence of the pressure and the temperature of metal pouring on the solid phase growth kinetics were estimated. The problem has been solved by the finite element method.

  8. CAE applications in a thermoforming mould design

    International Nuclear Information System (INIS)

    Marjuki, AR; Mohd Ghazali, FA; Ismail, N M; Sulaiman, S; Mohd Khairuddin, I; Majeed, Anwar P P A; Jaafar, AA; Basri, S; Mustapha, F

    2016-01-01

    Preparation of honeycomb layer is a critical step for successful fabrications of thermoformed based sandwiched structures. This paper deals with an initial investigation on the rapid manufacturing process of corrugated sheet with 120° dihedral angles. Time history of local displacements and thickness, assuming viscous dominated material model for a 1mm thick thermoformable material, was computed by using ANSYS ® Polyflow solver. The quality of formed surfaces was evaluated for selection of mould geometry and assessment of two common variants of thermoforming process. Inadequate mesh refinement of a membrane elements produces satisfactorily detailing and incomplete forming. A perfectly uniform material distribution was predicted using drape forming process. However, the geometrical properties of vacuum formed part are poorly distributed and difficult to control with increasing inflation volumes. Details of the discrepancies and the contributions of the CAE tool to complement traditional trial and error methodology in the process and design development are discussed. (paper)

  9. Application of microwaves for incinerating waste shell moulds and cores

    Directory of Open Access Journals (Sweden)

    K. Granat

    2008-08-01

    Full Text Available In the paper, investigation results of microwave heating application for incinerating waste shell moulds and cores made of moulding sands with thermosetting resins are presented. It was found that waste shell cores or shell moulds left after casting, separated from moulding sand, can be effectively incinerated. It was evidenced that microwave heating allows effective control of this process and its results. Incineration of waste moulds and cores made of commercial grades of resin-coated moulding sand using microwave heating was found to be an effective way of their utilisation. It was determined that the optimum burning time of these wastes (except those insufficiently disintegrated and not mixed with an activating agent is maximum 240 s at the used magnetron power of 650 W. It was noticed that proper disintegration of the wastes and use of suitable additives to intensify the microwave heating process guarantee significant reduction of the process time and its full stabilisation. Application of microwave heating for incinerating waste shell moulds and cores ensure substantial and measurable economic profits due to shorter process time and lower energy consumption.

  10. Study of process parameters on two phase flow agitated by top blowing lance injection into a bath

    Energy Technology Data Exchange (ETDEWEB)

    Xia Jiliang; Ahokainen, T.; Holappa, L.

    1998-12-31

    Numerical investigation has been carried out for two phase flow in a bath agitated by top blowing lance injection. Eulerian two phase flow model is used. Lance immersion depth, injection gas flow rate, nozzle diameter, and bubble size have been systematically changed to examine their influence on the flow characteristics in the bath. It is found that there appear three typical flow patterns: one-vortex, two-vortex, and three-vortex type, with changing the injection gas flow rate or/and the nozzle diameter at moderate lance immersion depth. Predicted velocities are in a good agreement with Iguchi et al.`s experimental data and the main findings are also consistent with the measurements and observations of Chatterjee and Hsiao and Lehner. (orig.) 24 refs. Computational Fluid Dynamics Technology Programme

  11. The Compositions: Biodegradable Material - Typical Resin, as Moulding Sands’ Binders

    Directory of Open Access Journals (Sweden)

    Major-Gabryś K.

    2015-03-01

    Full Text Available The paper presents possibility of using biodegradable materials as parts of moulding sands’ binders based on commonly used in foundry practice resins. The authors focus on thermal destruction of binding materials and thermal deformation of moulding sands with tested materials. All the research is conducted for the biodegradable material and two typical resins separately. The point of the article is to show if tested materials are compatible from thermal destruction and thermal deformation points of view. It was proved that tested materials characterized with similar thermal destruction but thermal deformation of moulding sands with those binders was different.

  12. Galactomyces geotrichum - moulds from dairy products with high biotechnological potential.

    Science.gov (United States)

    Grygier, Anna; Myszka, Kamila; Rudzińska, Magdalena

    2017-01-01

    The article reviews the properties of the Galactomyces geotrichum species, the mould that is most important for the dairy industry. G. geotrichum mould has been isolated from milk, cheeses and alcoholic beverage. Its presence in food products makes it possible to obtain a characteristic aroma and taste, which corresponds to the needs and preferences of consumers. G. geotrichum plays an important role in ecology, where the mould is employed for the degradation of various hazardous substances and wastewater treatment. It has also been found to have potential for biofuel production. In addition to this, G. geotrichum can be applicable in two further major areas: agriculture and health protection.

  13. Simulation of mould filling process for composite skeleton castings

    Directory of Open Access Journals (Sweden)

    M. Dziuba

    2008-04-01

    Full Text Available In this work authors showed selected results of simulation and experimental studies on temperature distribution during solidification of skeleton casting and mould filling process. The aim of conducted simulations was the choice of thermal and geometrical parameters for the needs of designed calculations of the skeleton castings and the estimation of the guidelines for the technology of manufacturing. The subject of numerical simulation was the analysis of ability of filling the channels of core by liquid metal at estability technological parameters.. Below the assumptions and results of the initial simulated calculations are presented. The total number of the nodes in the casting was 1920 and of the connectors was 5280 what gave filling of 100% for the nodes and 99,56% for the connectors in the results of the simulation. Together it resulted as 99,78 % of filling the volume of the casting. The nodes and connectors were filled up to the 30 level of the casting in the simulation. The all connectors were filled up to the 25 level of the casting in the simulation. Starting from the 25 level individual connectors at the side surface of the casting weren’t filled up. The connectors weren’t supplied by multi-level getting system. The differences of filling the levels are little (maximally 5 per cent.

  14. Evaluation of changes in skin biophysical parameters and appearance after pneumatic injections of non-cross-linked hyaluronic acid in the face.

    Science.gov (United States)

    Cheng, Hai-Yan; Chen, Yu-Xin; Wang, Mei-Fang; Zhao, Jun-Ying; Li, Lin-Feng

    2018-03-15

    Pneumatic injections of non-cross-linked hyaluronic acid are effective in skin rejuvenation, however, the associated biophysical parameters and appearance have not been evaluated. To determine the changes in skin biophysical parameters after facial pneumatic injections of non-cross-linked hyaluronic acid. Twenty-eight healthy female volunteers received pneumatic injections of non-cross-linked hyaluronic acid into the face for consecutive 5 weeks. Skin biophysical parameter assessment and clinical evaluation were performed using the CK Multi-Probe Adapter and Visia system. Five of the volunteers also underwent retroauricular skin biopsy before and after the last treatment. The skin tissues were all stained with Masson-trichrome, Verhoeff-van Gieson stain, and hematoxylin-eosin to evaluate the changes in collagen, elastic fibers, and the epidermis, before and after the last treatment. Transepidermal water loss was significantly lower in week 4 (18.46 ± 4.70 g/h/m 2 ) than at the baseline (22.03 ± 7.15 g/h/m 2 , p pores also improved significantly at week 4 (934.07 ± 458.78) compared to the baseline (1024.57 ± 415.31, p pores, and wrinkles.

  15. TRIGGERING COLLAPSE OF THE PRESOLAR DENSE CLOUD CORE AND INJECTING SHORT-LIVED RADIOISOTOPES WITH A SHOCK WAVE. II. VARIED SHOCK WAVE AND CLOUD CORE PARAMETERS

    Energy Technology Data Exchange (ETDEWEB)

    Boss, Alan P.; Keiser, Sandra A., E-mail: boss@dtm.ciw.edu, E-mail: keiser@dtm.ciw.edu [Department of Terrestrial Magnetism, Carnegie Institution, 5241 Broad Branch Road, NW, Washington, DC 20015-1305 (United States)

    2013-06-10

    A variety of stellar sources have been proposed for the origin of the short-lived radioisotopes that existed at the time of the formation of the earliest solar system solids, including Type II supernovae (SNe), asymptotic giant branch (AGB) and super-AGB stars, and Wolf-Rayet star winds. Our previous adaptive mesh hydrodynamics models with the FLASH2.5 code have shown which combinations of shock wave parameters are able to simultaneously trigger the gravitational collapse of a target dense cloud core and inject significant amounts of shock wave gas and dust, showing that thin SN shocks may be uniquely suited for the task. However, recent meteoritical studies have weakened the case for a direct SN injection to the presolar cloud, motivating us to re-examine a wider range of shock wave and cloud core parameters, including rotation, in order to better estimate the injection efficiencies for a variety of stellar sources. We find that SN shocks remain as the most promising stellar source, though planetary nebulae resulting from AGB star evolution cannot be conclusively ruled out. Wolf-Rayet (WR) star winds, however, are likely to lead to cloud core shredding, rather than to collapse. Injection efficiencies can be increased when the cloud is rotating about an axis aligned with the direction of the shock wave, by as much as a factor of {approx}10. The amount of gas and dust accreted from the post-shock wind can exceed that injected from the shock wave, with implications for the isotopic abundances expected for a SN source.

  16. Imprinted and injection-molded nano-structured optical surfaces

    DEFF Research Database (Denmark)

    Christiansen, Alexander Bruun; Højlund-Nielsen, Emil; Clausen, Jeppe Sandvik

    2013-01-01

    . In this paper, nanostructured polymer surfaces suitable for up-scalable polymer replication methods, such as imprinting/embossing and injection-molding, are discussed. The limiting case of injection-moulding compatible designs is investigated. Anti-reflective polymer surfaces are realized by replication...

  17. Magic with moulds: Meiotic and mitotic crossing over in Neurospora ...

    Indian Academy of Sciences (India)

    2006-02-16

    Feb 16, 2006 ... Home; Journals; Journal of Biosciences; Volume 31; Issue 1. Commentary: Magic with moulds: Meiotic and mitotic crossing over in Neurospora inversions and duplications. Durgadas P Kasbekar. Volume 31 Issue 1 March 2006 pp 3-4 ...

  18. Comparison of test methods for mould growth in buildings

    DEFF Research Database (Denmark)

    Bonderup, Sirid; Gunnarsen, Lars Bo; Knudsen, Sofie Marie

    2016-01-01

    renovation needs. This is of importance when hidden surface testing would require destructive measures and subsequent renovation. After identifying available methods on the Danish market for assessing mould growth in dwellings, a case study was conducted to test the usefulness of the methods in four......The purpose of this work is to compare a range of test methods and kits for assessing whether a building structure is infested by mould fungi. A further purpose of this work is to evaluate whether air-based methods for sampling fungal emissions provide information qualifying decisions concerning...... methods measure different aspects relating to mould growth and vary in selectivity and precision. The two types of air samples indicated low levels of mould growth, even where the results of the other methods indicated high to moderate growth. With methods based on culture and DNA testing some differences...

  19. Are motorways rational from slime mould's point of view?

    NARCIS (Netherlands)

    Adamatzky, A.; Akl, S.; Alonso-Sanz, R.; van Dessel, W.; Ibrahim, Z.; Ilachinski, A.; Jones, J.; Kayem, A.V.D.M.; Martínez, G.J.; de Oliveira, P.; Prokopenko, M.; Schubert, T.; Sloot, P.; Strano, E.; Yang, X.-S.

    2013-01-01

    We analyse the results of our experimental laboratory approximation of motorway networks with slime mould Physarum polycephalum. Motorway networks of 14 geographical areas are considered: Australia, Africa, Belgium, Brazil, Canada, China, Germany, Iberia, Italy, Malaysia, Mexico, the Netherlands, UK

  20. Sharp tipped plastic hollow microneedle array by microinjection moulding

    Science.gov (United States)

    Yung, K. L.; Xu, Yan; Kang, Chunlei; Liu, H.; Tam, K. F.; Ko, S. M.; Kwan, F. Y.; Lee, Thomas M. H.

    2012-01-01

    A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost.

  1. Sharp tipped plastic hollow microneedle array by microinjection moulding

    International Nuclear Information System (INIS)

    Yung, K L; Xu, Yan; Kang, Chunlei; Liu, H; Tam, K F; Ko, S M; Kwan, F Y; Lee, Thomas M H

    2012-01-01

    A method of producing sharp tipped plastic hollow microneedle arrays using microinjection moulding is presented in this paper. Unlike traditional approaches, three mould inserts were used to create the sharp tips of the microneedles. Mould inserts with low surface roughness were fabricated using a picosecond laser machine. Sharp tipped plastic hollow microneedles 500 µm in height were fabricated using a microinjection moulding machine developed by the authors’ group. In addition, the strength of the microneedle was studied by simulation and penetration experiments. Results show that the microneedles can penetrate into skin, delivering liquid successfully without any breakage or severe deformation. Techniques presented in this paper can be used to fabricate sharp tipped plastic hollow microneedle arrays massively with low cost. (paper)

  2. Thermal analysis control of in-mould and ladle inoculated grey cast irons

    Directory of Open Access Journals (Sweden)

    Mihai Chisamera

    2009-05-01

    Full Text Available The effect of addition of 0.05wt.% to 0.25 wt.% Ca, Zr, Al-FeSi alloy on in-ladle and in-mould inoculation of grey cast irons was investigated. In the present paper, the conclusions drawn are based on thermal analysis. For the solidification pattern, some specific cooling curves characteristics, such as the degree of undercooling at the beginning of eutectic solidifi cation and at the end of solidifi cation, as well as the recalescence level, are identifi ed to be more infl uenced by the inoculation technique. The degree of eutectic undercooling of the electrically melted base iron having 0.025% S, 0.003% Al and 3.5% Ce is excessively high (39–40℃, generating a relatively high need for inoculation. Under these conditions, the in-mould inoculation has a more signifi cant effect compared to ladle inoculation, especially at lower inoculant usage (less than 0.20 wt.%. Generally, the efficiency of 0.05wt.%–0.15wt.% of alloy for in-mould inoculation is comparable to, or better than, that of 0.15wt.%–0.25wt.% addition in ladle inoculation procedures. In order to secure stable and controlled processes, representative thermal analysis parameters could be used, especially in thin wall grey iron castings production.

  3. Identifying parameter windows for sulfur removal by direct limestone injection in the rich zone of staged heat engine combustors

    International Nuclear Information System (INIS)

    Colaluca, M.A.

    1990-01-01

    Recent experimental evidence suggests the possibility of sulfur cleanup by direct injection at gas temperatures that do not thermodynamically favor the absorption of sulfur by the limestone. The purpose of this paper is to analytically investigate possible mechanistic explanations of this observed sulfur capture with the goal of evaluating the potential for limestone injection sulfur capture in direct coal fired gas turbine and diesel engine (heat engines) combustion applications. The method was to use current available data on the physical properties of limestone, and the rates of the pertinent reactions, and to develop mathematical models of the processes experienced by the sorbent particles. The models were then used to predict extent of capture at the high-pressure, high-temperature, short residence time conditions of interest. The goal was to first investigate capture in a single-pulse reactor (combustion bomb) and then to extrapolate these results to advanced coal-fired heat engine combustion environments. Model predictions were in good agreement with observed sulfur capture in cold wall combustion bomb studies and suggest that efficient sulfur capture (in excess of 80 percent calcium utilization) may b e possible when limestone sorbents are injected into high-temperature combustion products, even when the gas temperatures exceed the thermodynamically favored temperature window by several hundred kelvins. This behavior is possible because particle temperatures are moderated and held at levels that favor sulfur capture due to the strongly endothermic calcination reaction

  4. Measuring autogenous strain of concrete with corrugated moulds

    DEFF Research Database (Denmark)

    Tian, Qian; Jensen, Ole Mejlhede

    2008-01-01

    A reliable technique to quantify autogenous strain is a prerequisite to numerical modeling in stress calculations for high performance concrete. The introducing of a special kind of corrugated tube mould helps to transforming volume strain measurement into liner strain measurement in horizontal...... direction for fluid concrete, which not only realizes the continuous monitoring of the autogenous shrinkage since casting, but also effectively eliminates the disturbance resulting from gravity, temperature variation and mould restraint on measuring results. Based on this measuring technique, this paper...

  5. Integrated hot-melt extrusion - injection molding continuous tablet manufacturing platform: Effects of critical process parameters and formulation attributes on product robustness and dimensional stability.

    Science.gov (United States)

    Desai, Parind M; Hogan, Rachael C; Brancazio, David; Puri, Vibha; Jensen, Keith D; Chun, Jung-Hoon; Myerson, Allan S; Trout, Bernhardt L

    2017-10-05

    This study provides a framework for robust tablet development using an integrated hot-melt extrusion-injection molding (IM) continuous manufacturing platform. Griseofulvin, maltodextrin, xylitol and lactose were employed as drug, carrier, plasticizer and reinforcing agent respectively. A pre-blended drug-excipient mixture was fed from a loss-in-weight feeder to a twin-screw extruder. The extrudate was subsequently injected directly into the integrated IM unit and molded into tablets. Tablets were stored in different storage conditions up to 20 weeks to monitor physical stability and were evaluated by polarized light microscopy, DSC, SEM, XRD and dissolution analysis. Optimized injection pressure provided robust tablet formulations. Tablets manufactured at low and high injection pressures exhibited the flaws of sink marks and flashing respectively. Higher solidification temperature during IM process reduced the thermal induced residual stress and prevented chipping and cracking issues. Polarized light microscopy revealed a homogeneous dispersion of crystalline griseofulvin in an amorphous matrix. DSC underpinned the effect of high tablet residual moisture on maltodextrin-xylitol phase separation that resulted in dimensional instability. Tablets with low residual moisture demonstrated long term dimensional stability. This study serves as a model for IM tablet formulations for mechanistic understanding of critical process parameters and formulation attributes required for optimal product performance. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Report on converging insert moulding with µ-IM

    DEFF Research Database (Denmark)

    Islam, Aminul

    moulding with µ-IM  Task 5.2.1 and COTECH demonstrator: guide line for 5PRC production based on the concept of Task 5.2.1 Information and results provided by this deliverable will be directly used for one of the COTECH demonstrators production which will call for convergent insert moulding with µ......Task 5.2.1 deals with the technical feasibility of converging the state-of-the-art µ IM process with insert moulding to offer a wide range of multi-material µ components. The main objective of this deliverable is to summarize state-of-the-art information and to make the guideline needed...... for the convergence. In particular the following aspects are summed up in the deliverable:  Need for converging insert moulding with µ-IM  Objectives and expected outcome from task 5.2.1  State-of-the-art micro insert moulding and different scenario of micro insert moulding  Challenges ahead of converging insert...

  7. Biosolubilization gamma irradiate ion result coal by mould trichoderma sp

    International Nuclear Information System (INIS)

    Pingkan Aditiawati; Dea Indriani Astuti; Irawan Sugoro; Dwiwahju Sasongko

    2011-01-01

    Biosolubilization of coal is process of converting solid coal to liquid fuel/chemicals by mean of microorganism. The aim of this research was to study the effect of gamma rays irradiation with varian doses of irradiation into solubilization of subbituminous coal by Trichoderma sp. The dosage used was 5, 10, and 20 kGy and unirradiated coal as control. The method was submerged culture in MSS+ medium and incubated at room temperature and agitated at 150 rpm for 21 th days. The parameters observed were colonization, pH and biosolubilization product based on absorbance value at λ 250nm and λ 450nm and GC/MS analysis for the best treatment. The results showed that coal biosolubilization could be increased by gamma irradiation. The mould could growth well in medium containing irradiated coal and the medium of pH was decreased after incubation. The biosolubilization was increased but the irradiation dosage of coal didn't affect significantly. The best dose was 20 kGy with product biosolubilization similar to gasoline and solar. Based on the result, the pre-treatment of gamma irradiation on coal has potency to increased biosolubilization. (author)

  8. Thermally induced atomic diffusion at the interface between release agent coating and mould substrate in a glass moulding press

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Jun; Fukase, Yasushi [Toshiba Machine Co., Ltd, Ooka 2068-3, Numazu-Shi, Shizuoka-Ken, 410-8510 (Japan); Yan Jiwang; Zhou Tianfeng; Kuriyagawa, Tsunemoto, E-mail: yanjw@pm.mech.tohoku.ac.jp [Department of Mechanical Systems and Design, Graduate School of Engineering, Tohoku University, Aoba 6-6-01, Aramaki, Aoba-ku, Sendai 980-8579 (Japan)

    2011-06-01

    In a glass moulding press (GMP) for refractive/diffractive hybrid lenses, to improve the service life of nickel-phosphorus (Ni-P) plated moulds, it is necessary to control the diffusion of constituent elements from the mould into the release agent coating. In this study, diffusion phenomena of constituents of Ni-P plating are investigated for two types of release agent coatings, iridium-platinum (Ir-Pt) and iridium-rhenium (Ir-Re), by cross-sectional observation, compositional analysis and stress measurements. The results show that Ni atoms in the plating layer flow from regions of compressive stress to regions of tensile stress. In the case of the Ir-Pt coated mould, the diffusion of Ni is promoted from the grain boundaries between the Ni and Ni{sub 3}P phases in the plating towards the surface of the Ir-Pt coating. However, in the Ir-Re coated mould, the diffusion of Ni is suppressed because the diffusion coefficient of Ni in the Ir-Re alloy is smaller than that in the Ir-Pt alloy, although the stress state is similar in both cases. By controlling the diffusion of Ni atoms, the use of Ir-Re alloy as a release agent coating for Ni-P plated moulds is expected to lead to a high degree of durability.

  9. CONTRIBUTIONS TO DIVERSIFY SOLES MOULDS THAT FORMS DIRECTLY ON FACES SHOES

    Directory of Open Access Journals (Sweden)

    IONESCU Cozmin

    2015-05-01

    Full Text Available The classical moulds which are currently used for forming the soles directly on the uppers, allow obtaining one sole model. One mould for each foot is made, and at least one mould for each size number in the size number series. To manufacture one single sole model in the sizes series an average set of 16 moulds are needed. Changing the model implies the entire production of a new set of moulds. Therefore, a large diversification of the soles requires the manufacturing a quantity of moulds sets equal with the quantity of sole models. In this paper are presented solutions to obtain more cavity shapes in the same mould, through the use of modular interchangeable pieces. The moulds with versatile cavities have the same functional characteristics as the moulds with unique cavities, are usable on the same type of machines and can be used independently or together with the classical moulds. A brief analysis on the technological processes for manufacturing moulds with versatile cavities reveals a significant lowering of the manufacturing time for moulds in which will be obtained other sole models. This is due to the fact that some of the mould parts are reused. In conclusion, the producers that chose this type of moulds can launch on the market new models in a shorter time and at lower prices.

  10. Investigation of the effect of nanoclay and processing parameters on the tensile strength and hardness of injection molded Acrylonitrile Butadiene Styrene–organoclay nanocomposites

    International Nuclear Information System (INIS)

    Mamaghani Shishavan, Sajjad; Azdast, Taher; Rash Ahmadi, Samrand

    2014-01-01

    Highlights: • Development of polymer/clay nanocomposites. • Compatibility of ABS and montmorillonite nanoclay and composition capability of them. • Effect of nanoclay content and process parameters on the mechanical properties of nanocomposite. • Analyzing the distribution of nanoclay layers using XRD test. • Dependency of tensile strength and hardness to the nanoclay content and processing conditions. - Abstract: Polymer–clay nanocomposites have attracted considerable interest over recent years due to their dramatic improved mechanical properties. In the present study, compatibility of Acrylonitrile Butadiene Styrene (ABS) and organically modified montmorillonite nanoclay (Cloisite 30B) and composition capability of them are investigated. Polymethylmethacrylate (PMMA) in varying amount (0, 2, and 4 wt%) is used as the compatibilizer. In order to produce nanocomposite parts, the material is first compounded using a twin-screw extruder and then injected into a mold. The effect of the nanoclay percentage and processing parameters on the tensile strength and hardness of nanocomposite parts is also explored using Taguchi Design of Experiments method. Nanoclay content (in three levels: 0, 2 and 4 wt%), melt temperature (in three levels: 190, 200 and 210 °C), holding pressure (in three levels: 80, 105 and 130 MPa) and holding pressure time (in three levels: 1, 2.5 and 4 s) are considered as the variable parameters. Moreover, distribution of nanoclay layers is analyzed using Wide Angle X-ray Diffraction (XRD) test. XRD results displayed that with the presence of PMMA, nanoclay in ABS matrix is compounded in more exfoliated and less intercalated dispersion mode. Adding PMMA also leads to a remarkable increase in the fluidity of the melt during injection molding process. Results also illustrated that nanocomposites with medium loading level (i.e. 2%) of nanoclay have the highest tensile strength, while the highest hardness number belongs to nanocomposites with

  11. ASSESSMENT OF SURFACE FINISH AND DIMENSIONAL ACCURACY OF TOOLS MANUFACTURED BY METAL CASTING IN RAPID PROTOTYPING SAND MOULDS

    Directory of Open Access Journals (Sweden)

    Nyembwe, K.

    2012-11-01

    Full Text Available In this paper, an initial assessment of the quality parameters of the surface finish and dimensional accuracy of tools made by metal casting in rapid prototyping (RP sand moulds is undertaken. A case study from a local tool room, dealing with the manufacturing of an aluminium die for the lost wax process, is employed. Modern techniques, including surface roughness analysis and three dimensional scanning, are used to determine and understand how each manufacturing step influences the final quality of the cast tool. The best surface finish obtained for the cast die had arithmetic average roughness (Ra and mean average roughness (Rz respectively equal to 3.23m and 11.38m. In terms of dimensional accuracy, 82% of cast-die points coincided with the Computer Aided Design (CAD data, which is within the typical tolerances of sand cast products. The investigation shows that mould coating contributes slightly to the improvement of the cast tool surface finish. The study also found that the additive manufacturing of the sand mould was the chief factor responsible for the loss of dimensional accuracy. These findings indicate that machining will always be required to improve the surface finish and the dimensional accuracy of cast tools in RP sand moulds.

  12. The first report on mushroom green mould disease in Croatia.

    Science.gov (United States)

    Hatvani, Lóránt; Sabolić, Petra; Kocsubé, Sándor; Kredics, László; Czifra, Dorina; Vágvölgyi, Csaba; Kaliterna, Joško; Ivić, Dario; Đermić, Edyta; Kosalec, Ivan

    2012-12-01

    Green mould disease, caused by Trichoderma species, is a severe problem for mushroom growers worldwide, including Croatia. Trichoderma strains were isolated from green mould-affected Agaricus bisporus (button or common mushroom) compost and Pleurotus ostreatus (oyster mushroom) substrate samples collected from Croatian mushroom farms. The causal agents of green mould disease in the oyster mushroom were T. pleurotum and T. pleuroticola, similar to other countries. At the same time, the pathogen of A. bisporus was exclusively the species T. harzianum, which is different from earlier findings and indicates that the range of mushroom pathogens is widening. The temperature profiles of the isolates and their hosts overlapped, thus no range was found that would allow optimal growth of the mushrooms without mould contamination. Ferulic acid and certain phenolic compounds, such as thymol showed remarkable fungistatic effect on the Trichoderma isolates, but inhibited the host mushrooms as well. However, commercial fungicides prochloraz and carbendazim were effective agents for pest management. This is the first report on green mould disease of cultivated mushrooms in Croatia.

  13. Early changes in macular optical coherence tomography parameters after Ranibizumab intravitreal injection in patients with exsudative age-related macular degeneration.

    Science.gov (United States)

    de Almeida, Nicole Antunes; de Souza, Osias Francisco

    2018-01-01

    Evaluation of the impact of different macular optical coherence parameters on visual acuity as early as 1 day after injection of ranibizumab in patients with subfoveal exsudative age-related macular degeneration. This was an interventional, non randomized, open label prospective study, where we evaluated 20 eyes of 20 patients affected by exudative age-related macular degeneration. These patients were treated with injections of ranibizumab between February 2013 and January 2015. The primary endpoint of this study was to evaluate the early changes in optical coherence tomography parameters (retinal thickness, central and total retinal volume) and impact on best-corrected visual acuity (BCVA) obtained by logarithm of minimum resolution using ETDRS protocol in patients treated with a single dose intravitreal injection of ranibizumab (0.5 mg/0.05 mL) during the first month of follow. The patients were evaluated on the first day, them at 7 and 30 days after the treatment. The National Eye Institute Visual Functioning Questionnaire was applied during the study period to assess early perception of ranibizumab injection effectiveness. The adverse events were monitored throughout the study. Central retinal thickness values at 1 (464.0 ± 97.8 µm), 7 (379.9 ± 107.8 µm) and 30 days (365.5 ± 95.1 µm) after ranibizumab injection showed a statically significant reduction when compared with baseline results ( P  = 0.01, P  = 0.001, P  = 0.001, respectively). Similar alterations were observed in central and total retinal volume, which were detected early on the first day of evaluation, after the measurement at baseline (central: 0.36 ± 0.07 vs. 0.40 ± 0.10 mm 3 , P  = 0.01; total: 9.62 ± 1.10 vs. 9.99 ± 2.56 mm 3 , P  = 0.002) and remained steady at 7 ( P  = 0.001, P  = 0.002, respectively) and 30 days ( P  = 0.001, P  = 0.004, respectively) with slight variations without losing their gains in these parameters. The best

  14. PLC and SCADA based automation of injection casting process for casting of uranium-zirconium blanket fuel slugs for metallic fuel fabrication

    International Nuclear Information System (INIS)

    Yathish Kumar, G.; Jagadeeschandran, J.; Avvaru, Prafulla Kumar; Yadaw, Abhishek Kumar; Lavakumar, R.; Prabhu, T.V.; Muralidharan, P.; Anthonysamy, S.

    2016-01-01

    Fabrication of metallic (U-6wt.%Zr) slugs involves melting of binary alloy under vacuum and injection casting into quartz moulds at high pressure. Injection casting system housed inside glove box comprises of high vacuum, induction melting, high pressure control, motion control, mould preheating, chamber cooling, crucible handling and glove box pressure control systems. The technology development for process automation of injection casting system and process optimisation for fabrication of metallic (U-6%Zr) slugs is outlined in this paper. (author)

  15. Optimization of Injection Molding Parameters for HDPE/TiO₂ Nanocomposites Fabrication with Multiple Performance Characteristics Using the Taguchi Method and Grey Relational Analysis.

    Science.gov (United States)

    Pervez, Hifsa; Mozumder, Mohammad S; Mourad, Abdel-Hamid I

    2016-08-22

    The current study presents an investigation on the optimization of injection molding parameters of HDPE/TiO₂ nanocomposites using grey relational analysis with the Taguchi method. Four control factors, including filler concentration (i.e., TiO₂), barrel temperature, residence time and holding time, were chosen at three different levels of each. Mechanical properties, such as yield strength, Young's modulus and elongation, were selected as the performance targets. Nine experimental runs were carried out based on the Taguchi L₉ orthogonal array, and the data were processed according to the grey relational steps. The optimal process parameters were found based on the average responses of the grey relational grades, and the ideal operating conditions were found to be a filler concentration of 5 wt % TiO₂, a barrel temperature of 225 °C, a residence time of 30 min and a holding time of 20 s. Moreover, analysis of variance (ANOVA) has also been applied to identify the most significant factor, and the percentage of TiO₂ nanoparticles was found to have the most significant effect on the properties of the HDPE/TiO₂ nanocomposites fabricated through the injection molding process.

  16. Optimization of Injection Molding Parameters for HDPE/TiO2 Nanocomposites Fabrication with Multiple Performance Characteristics Using the Taguchi Method and Grey Relational Analysis

    Directory of Open Access Journals (Sweden)

    Hifsa Pervez

    2016-08-01

    Full Text Available The current study presents an investigation on the optimization of injection molding parameters of HDPE/TiO2 nanocomposites using grey relational analysis with the Taguchi method. Four control factors, including filler concentration (i.e., TiO2, barrel temperature, residence time and holding time, were chosen at three different levels of each. Mechanical properties, such as yield strength, Young’s modulus and elongation, were selected as the performance targets. Nine experimental runs were carried out based on the Taguchi L9 orthogonal array, and the data were processed according to the grey relational steps. The optimal process parameters were found based on the average responses of the grey relational grades, and the ideal operating conditions were found to be a filler concentration of 5 wt % TiO2, a barrel temperature of 225 °C, a residence time of 30 min and a holding time of 20 s. Moreover, analysis of variance (ANOVA has also been applied to identify the most significant factor, and the percentage of TiO2 nanoparticles was found to have the most significant effect on the properties of the HDPE/TiO2 nanocomposites fabricated through the injection molding process.

  17. Optimization of Injection Molding Parameters for HDPE/TiO2 Nanocomposites Fabrication with Multiple Performance Characteristics Using the Taguchi Method and Grey Relational Analysis

    Science.gov (United States)

    Pervez, Hifsa; Mozumder, Mohammad S.; Mourad, Abdel-Hamid I.

    2016-01-01

    The current study presents an investigation on the optimization of injection molding parameters of HDPE/TiO2 nanocomposites using grey relational analysis with the Taguchi method. Four control factors, including filler concentration (i.e., TiO2), barrel temperature, residence time and holding time, were chosen at three different levels of each. Mechanical properties, such as yield strength, Young’s modulus and elongation, were selected as the performance targets. Nine experimental runs were carried out based on the Taguchi L9 orthogonal array, and the data were processed according to the grey relational steps. The optimal process parameters were found based on the average responses of the grey relational grades, and the ideal operating conditions were found to be a filler concentration of 5 wt % TiO2, a barrel temperature of 225 °C, a residence time of 30 min and a holding time of 20 s. Moreover, analysis of variance (ANOVA) has also been applied to identify the most significant factor, and the percentage of TiO2 nanoparticles was found to have the most significant effect on the properties of the HDPE/TiO2 nanocomposites fabricated through the injection molding process. PMID:28773830

  18. 2k micro moulding for MID fabrication

    DEFF Research Database (Denmark)

    Islam, Aminul; Hansen, Hans Nørgaard; Jørgensen, Martin Bondo

    2009-01-01

    Molded Interconnect Devices (MIDs) are plastic substrates with electrical infrastructure. The fabrication of MIDs is usually based on injection molding and different process chains may be identified from this starting point. The use of MIDs has been driven primarily by the automotive sector......, but recently the medical sector seems more and more interested. In particular, the possibility of miniaturization of 3D components with electrical infrastructure is attractive. The paper describes possible manufacturing routes and challenges of miniaturized MIDs based on two component injection molding...

  19. Potentially pathogenic, pathogenic, and allergenic moulds in the urban soils

    Directory of Open Access Journals (Sweden)

    Đukić Dragutin A.

    2011-01-01

    Full Text Available The dynamics of soil mould populations that can compromise the human immune system was evaluated in experimental plots located at different distances (100, 300, 500, 700 and 900 m from the main source of pollution - the Podgorica Aluminum Plant. Soil samples were collected in July and October 2008 from three different plot zones at a depth of 0-10 cm. The count of potentially pathogenic, keratinolytic and allergenic (melaninogenic moulds was assessed, which can significantly contribute to both diagnosis and prophylaxis. The count of medically important moulds was higher in the urban soil than in the unpolluted (control soil. Their count decreased with increasing distance from the main pollution source (PAP. Their abundance in the soil was considerably higher in autumn than in spring.

  20. Normalization in Lie algebras via mould calculus and applications

    Science.gov (United States)

    Paul, Thierry; Sauzin, David

    2017-11-01

    We establish Écalle's mould calculus in an abstract Lie-theoretic setting and use it to solve a normalization problem, which covers several formal normal form problems in the theory of dynamical systems. The mould formalism allows us to reduce the Lie-theoretic problem to a mould equation, the solutions of which are remarkably explicit and can be fully described by means of a gauge transformation group. The dynamical applications include the construction of Poincaré-Dulac formal normal forms for a vector field around an equilibrium point, a formal infinite-order multiphase averaging procedure for vector fields with fast angular variables (Hamiltonian or not), or the construction of Birkhoff normal forms both in classical and quantum situations. As a by-product we obtain, in the case of harmonic oscillators, the convergence of the quantum Birkhoff form to the classical one, without any Diophantine hypothesis on the frequencies of the unperturbed Hamiltonians.

  1. Numerical study of crucial parameters in tilt casting for titanium aluminides

    Directory of Open Access Journals (Sweden)

    Hong Wang

    2011-08-01

    Full Text Available Numerical modeling of the tilt casting process for TiAl alloys was investigated to achieve a tranquil mould filling and TiAl castings free of defects. Titanium alloys are very reactive in molten state, so they are widely melted in cold crucible, e.g. the Induction Skull Melting (ISM furnace. Then the crucible holding the molten metal together with the mould is rotated to transfer the metal into the mould — ISM+ tilt casting. This paper emphasizes the effect of crucial parameters on mould filling and solidification of the castings during tilt casting. All crucial parameters, such as rotation rate, rotation profile, venting, initial mould temperature, casting orientation, feeder design, change of radius in 'T' junction and mould insulation have been discussed using numerical modeling data. Simulations were performed using a 3D CFD code PHYSICA implemented with front tracking, heat transfer algorithms and a turbulence model (which accounts for an advancing solid front.

  2. Approximations for transport parameters and self-averaging properties for point-like injections in heterogeneous media

    International Nuclear Information System (INIS)

    Eberhard, Jens

    2004-01-01

    We focus on transport parameters in heterogeneous media with a flow modelled by an ensemble of periodic and Gaussian random fields. The parameters are determined by ensemble averages. We study to what extent these averages represent the behaviour in a single realization. We calculate the centre-of-mass velocity and the dispersion coefficient using approximations based on a perturbative expansion for the transport equation, and on the iterative solution of the Langevin equation. Compared with simulations, the perturbation theory reproduces the numerical results only poorly, whereas the iterative solution yields good results. Using these approximations, we investigate the self-averaging properties. The ensemble average of the velocity characterizes the behaviour of a realization for large times in both ensembles. The dispersion coefficient is not self-averaging in the ensemble of periodic fields. For the Gaussian ensemble the asymptotic dispersion coefficient is self-averaging. For finite times, however, the fluctuations are so large that the average does not represent the behaviour in a single realization

  3. Optimisation of multi-layer rotationally moulded foamed structures

    Science.gov (United States)

    Pritchard, A. J.; McCourt, M. P.; Kearns, M. P.; Martin, P. J.; Cunningham, E.

    2018-05-01

    Multi-layer skin-foam and skin-foam-skin sandwich constructions are of increasing interest in the rotational moulding process for two reasons. Firstly, multi-layer constructions can improve the thermal insulation properties of a part. Secondly, foamed polyethylene sandwiched between solid polyethylene skins can increase the mechanical properties of rotationally moulded structural components, in particular increasing flexural properties and impact strength (IS). The processing of multiple layers of polyethylene and polyethylene foam presents unique challenges such as the control of chemical blowing agent decomposition temperature, and the optimisation of cooling rates to prevent destruction of the foam core; therefore, precise temperature control is paramount to success. Long cooling cycle times are associated with the creation of multi-layer foam parts due to their insulative nature; consequently, often making the costs of production prohibitive. Devices such as Rotocooler®, a rapid internal mould water spray cooling system, have been shown to have the potential to significantly decrease cooling times in rotational moulding. It is essential to monitor and control such devices to minimise the warpage associated with the rapid cooling of a moulding from only one side. The work presented here demonstrates the use of threaded thermocouples to monitor the polymer melt in multi-layer sandwich constructions, in order to analyse the cooling cycle of multi-layer foamed structures. A series of polyethylene skin-foam test mouldings were produced, and the effect of cooling medium on foam characteristics, mechanical properties, and process cycle time were investigated. Cooling cycle time reductions of 45%, 26%, and 29% were found for increasing (1%, 2%, and 3%) chemical blowing agent (CBA) amount when using internal water cooling technology from ˜123°C compared with forced air cooling (FAC). Subsequently, a reduction of IS for the same skin-foam parts was found to be 1%, 4

  4. ASSESSMENT OF SURFACE FINISH AND DIMENSIONAL ACCURACY OF TOOLS MANUFACTURED BY METAL CASTING IN RAPID PROTOTYPING SAND MOULDS

    OpenAIRE

    Nyembwe, K.; De Beer, D. J.; Van der Walt, J. G.; Bhero, S.

    2012-01-01

    In this paper, an initial assessment of the quality parameters of the surface finish and dimensional accuracy of tools made by metal casting in rapid prototyping (RP) sand moulds is undertaken. A case study from a local tool room, dealing with the manufacturing of an aluminium die for the lost wax process, is employed. Modern techniques, including surface roughness analysis and three dimensional scanning, are used to determine and understand how each manufacturing step influences the final qu...

  5. Presurgical nasoalveolar moulding in unilateral cleft lip and palate

    Directory of Open Access Journals (Sweden)

    Mohammed Zuhaib

    2016-01-01

    Full Text Available Context: Presurgical nasoalveolar moulding (PNAM is a non-surgical method of reshaping the cleft lip, alveolus, palate and the nose to minimize the severity of the cleft deformity, before primary cheiloplastyand palatoplasty. In this context, PNAM proves to be an invaluable asset in the management of unilateral cleft lip and palate. Aims: The study was conducted to evaluate the effi cacy of PNAM in the management of unilateral cleft lip and palate with the following objectives: (1 To assess and compare the degree of reduction in the size of cleft palate and alveolus (pre-PNAM and post-PNAM. (2 To evaluate and compare the improvement in columellar length and correction of columellar deviation (pre-PNAM and post-PNAM. (3 To assess the changes in the position of the alar base and the alar cartilages. Settings and Design: Prospective study. Subjects and Methods: A prospective study consisting of, which included 20 patients with complete unilateral cleft lip and palate was conducted. The age at the start of PNAM treatment of the infants ranged from 2 to 44 days of age reporting to our institute between December 2011 and August 2013. All the patients underwent PNAM therapy before primary cheiloplasty at 6 months of age; clinical parameters were assessed pre- and post-therapy using photographs and dental study models of the maxilla. Statistical Analysis Used: Student's t-test for paired comparisons. Results: Results of the study showed a promising reduction in the cleft size before the surgery, signifi cant improvement in nasal symmetry, including the columellar length on the cleft side. Conclusions: PNAM is a valuable adjunct to our surgical armamentarium in dealing with the challenges of primary closure of unilateral cleft lip and palate thereby enhancing the overall surgical outcome. The advantages of this method include the simplicity of the procedure and improving the quality of surgical repair, particularly in obtaining tension free muscle

  6. The estimation of harmfulness for environment of moulding sand with biopolymer binder based on polylactide

    Directory of Open Access Journals (Sweden)

    K. Major-Gabryś

    2011-01-01

    Full Text Available The article takes into consideration technological and ecological aspects of IV generation moulding sands. Investigations concerning anapplication of biopolymer materials as binders for moulding sands are presented in the paper. These investigations are the continuation ofexaminations related to applications of various biopolymers as binding agents and to the properties of the moulding sands with biopolymerbinders. In the paper there are the researches concerning analyzing gases emitted from moulding sands during heating.

  7. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    DEFF Research Database (Denmark)

    Hovad, Emil; Larsen, P.; Walther, Jens Honore

    2015-01-01

    casting process. Depending on the actual casting geometry the mould can be geometrically quite complex involving e.g. shadowing effects and this is directly reflected in the sand flow during the moulding process. In the present work a mould chamber with “ribs” at the walls is chosen as a baseline geometry...

  8. Double-curved precast concrete elements : Research into technical viability of the flexible mould method

    NARCIS (Netherlands)

    Schipper, H.R.

    2015-01-01

    The production of precast, concrete elements with complex, double-curved geometry is expensive due to the high costcosts of the necessary moulds and the limited possibilities for mould reuse. Currently, CNC-milled foam moulds are the solution applied mostly in projects, offering good aesthetic

  9. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat; Crepaz, Rudolf; Eggert, Torben

    2010-01-01

    compositions were tested. A test method that provides uniform test conditions is described. The method can be used as general test method to analyse off gasses from binders. Moulds containing a standard size casting were produced and the amount and type of organic compounds resulting from thermal degradation...... of binders was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gasses in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO content...

  10. Impact of parameter fluctuations on the performance of ethanol precipitation in production of Re Du Ning Injections, based on HPLC fingerprints and principal component analysis.

    Science.gov (United States)

    Sun, Li-Qiong; Wang, Shu-Yao; Li, Yan-Jing; Wang, Yong-Xiang; Wang, Zhen-Zhong; Huang, Wen-Zhe; Wang, Yue-Sheng; Bi, Yu-An; Ding, Gang; Xiao, Wei

    2016-01-01

    The present study was designed to determine the relationships between the performance of ethanol precipitation and seven process parameters in the ethanol precipitation process of Re Du Ning Injections, including concentrate density, concentrate temperature, ethanol content, flow rate and stir rate in the addition of ethanol, precipitation time, and precipitation temperature. Under the experimental and simulated production conditions, a series of precipitated resultants were prepared by changing these variables one by one, and then examined by HPLC fingerprint analyses. Different from the traditional evaluation model based on single or a few constituents, the fingerprint data of every parameter fluctuation test was processed with Principal Component Analysis (PCA) to comprehensively assess the performance of ethanol precipitation. Our results showed that concentrate density, ethanol content, and precipitation time were the most important parameters that influence the recovery of active compounds in precipitation resultants. The present study would provide some reference for pharmaceutical scientists engaged in research on pharmaceutical process optimization and help pharmaceutical enterprises adapt a scientific and reasonable cost-effective approach to ensure the batch-to-batch quality consistency of the final products. Copyright © 2016 China Pharmaceutical University. Published by Elsevier B.V. All rights reserved.

  11. Inhibition of growth and mycotoxins formation in moulds by marine ...

    African Journals Online (AJOL)

    ... extracts (chloroform, hexane and methanol) had no activity on the microbial growth. Mycotoxins formation in Aspergillus flavus was inhibited by the ethanolic extracts at the concentration of 5%. Key Words: Algae, antimicrobial, minimal inhibitory concentration, moulds. African Journal of Biotechnology Vol.3(1) 2004: 71-75 ...

  12. Effect of increased manganese addition and mould type on the ...

    Indian Academy of Sciences (India)

    Administrator

    Effect of increased manganese addition and mould type on the slurry erosion characteristics of .... slurry erosion data in the form of bar diagrams for 5M24 and 10M24 ... being bigger in size with higher austenite retention and the attendant ...

  13. Wood working: planing and moulding in the last frontier

    Science.gov (United States)

    David Nicholls

    2007-01-01

    Planing and moulding is an important step in the value-added manufacture of wood products, and recent advances in Alaska have been noteworthy. Just a few years ago, most planing occurred on simple shop planers, producing lumber for retail sale or for wood working uses such as cabinet stock. Currently there are at least 26 planers and 13 moulders in-production at...

  14. Exploring Value-Added Options - Opportunities in Mouldings and Millwork

    Science.gov (United States)

    Bob Smith; Philip A. Araman

    1997-01-01

    The millwork industry, which includes manufacture of doors, windows, stair parts, blinds, mouldings, picture frame material, and assorted trim, can be a lucrative value-added opportunity for sawmills. Those entering the value-added millwork market often find that it is a great opportunity to generate greater profits from upper grades and utility species, such as yellow...

  15. Immunological and biochemical characterization of extracellular polysaccharides of mucoralean moulds

    NARCIS (Netherlands)

    Ruiter, de G.A.

    1993-01-01

    In this thesis the characterization is described of the antigenic determinants (epitopes) of the extracellular polysaccharides (EPSs) from moulds belonging to the order of Mucorales. Detailed knowledge of the structure of these epitopes allows for further development of a new generation of

  16. On the epoxy moulding compound aging effect on package reliability

    NARCIS (Netherlands)

    Noijen, S.P.M.; Engelen, R.A.B.; Martens, J.; Opran, A.; Sluis, van der O.

    2009-01-01

    Most semi-conductor devices are encapsulated by epoxy moulding compound (EMC) material. Even after curing at the prescribed temperature and time in accordance with the supplier's curing specifications often the product is not yet 100% fully cured. As a consequence, the curing process of a product

  17. Mucoraceous moulds involved in the commercial fermentation of Sufu Pehtze

    NARCIS (Netherlands)

    Han, B.; Kuijpers, F.A.; Thanh, N.V.; Nout, M.J.R.

    2004-01-01

    Sufu is a fermented cheese-like soybean product in China and Vietnam, obtained by fungal solid-state fermentation of soybean curd (tofu), which results in moulded tofu or 'pehtze'. The final product sufu is obtained by maturing pehtze in a brine containing alcohol and salt during a period of several

  18. Evolution of Surface Texture and Cracks During Injection Molding of Fiber-Reinforced, Additively-Manufactured, Injection Molding Inserts

    DEFF Research Database (Denmark)

    Hofstätter, Thomas; Mischkot, Michael; Pedersen, David Bue

    2016-01-01

    This paper investigates the lifetime and surfacedeterioration of additively-manufactured, injection-moulding inserts. The inserts were produced using digital light processing and were reinforcedwith oriented short carbon fibers. Theinserts were used during injection molding oflow-density polyethy......This paper investigates the lifetime and surfacedeterioration of additively-manufactured, injection-moulding inserts. The inserts were produced using digital light processing and were reinforcedwith oriented short carbon fibers. Theinserts were used during injection molding oflow......-density polyethylene until their failure. The molded products were used to analyse the development of the surface roughness and wear. By enhancing the lifetime of injection-molding inserts,this work contributes to the establishment of additively manufactured inserts in pilot production....

  19. Assessment of Mould Growth for Library Buildings in Tropical Climates

    Directory of Open Access Journals (Sweden)

    Ngah Abdul Wahab S.

    2014-01-01

    Full Text Available This paper attempt to give a brief insight into the importance of studying mould growth in library building that relates to human health and causes of material deterioration to library materials. It’s significant to conduct this research because no similar study has carried out for a library building in Malaysia. Recent literature on the topics reviews to gain insight into developing a theoretical framework and research method. Likewise, the study also supports through pilot study questionnaires with 30 respondents from two different university libraries. The finding revealed to further investigation and mould growth assessment to be conducted that useful in protecting library materials and users health effects through environmental control.

  20. Development and Evaluation of Mould for Double Curved Concrete Elements

    DEFF Research Database (Denmark)

    Jepsen, Christian Raun; Kristensen, Mathias Kræmmergaard; Kirkegaard, Poul Henning

    2011-01-01

    freeform concrete formwork are available, and more are being developed [1-4]. The common way of producing moulds for unique elements today is to manufacture one mould for each unique element using CNC milling in cheaper materials, but since the method is still labour intensive and produces a lot of waste......Complex freeform architecture is one of the most striking trends in contemporary architecture. Architecture differs from traditional target industries of CAD/CAM technology in many ways including aesthetics, statics, structural aspects, scale and manufacturing technologies. Designing a piece...... of freeform architecture in a CAD program is fairly easy, but the translation to a real piece of architecture can be difficult and expensive and as traditional production methods for free-form architecture prove costly, architects and engineers are forced to simplify designs. Today, methods for manufacturing...

  1. SQL injection detection system

    OpenAIRE

    Vargonas, Vytautas

    2017-01-01

    SQL injection detection system Programmers do not always ensure security of developed systems. That is why it is important to look for solutions outside being reliant on developers. In this work SQL injection detection system is proposed. The system analyzes HTTP request parameters and detects intrusions. It is based on unsupervised machine learning. Trained by regular request data system detects outlier user parameters. Since training is not reliant on previous knowledge of SQL injections, t...

  2. Mould growth prediction by computational simulation on historic buildings

    OpenAIRE

    Krus, M.; Kilian, R.; Sedlbauer, K.

    2007-01-01

    Historical buildings are often renovated with a high expenditure of time and money without investigating and considering the causes of the damages. In many cases historic buildings can only be maintained by changing their usage. This change of use may influence the interior climate enormously. To assess the effect on the risk of mould growth on building parts or historic monuments a predictive model has been developed recently, describing the hygrothermal behaviour of the spore. It allows for...

  3. Moulded Pulp Manufacturing: Overview and Prospects for the Process Technology

    DEFF Research Database (Denmark)

    Didone, Mattia; Saxena, Prateek; Meijer, Ellen Brilhuis

    2017-01-01

    Eco-friendly packaging such as moulded pulp products have gained commercial importance in the recent years. However, it remains a greatly under-researched area, and there is an arising need to consolidate the best practices from research and industry in order to increase its implementation....... Moreover, based on the latest research in the field, an innovative drying technique that utilizes concepts derived from impulse drying is presented, and the implementation of this process technology is discussed....

  4. Application of Microwaves for Binder Content Assessment in Moulding Sands

    Directory of Open Access Journals (Sweden)

    Nowak D.

    2012-09-01

    Full Text Available The paper presents results of preliminary examinations on possibility of determining binder content in traditional moulding sands with the microwave method. The presented measurements were carried-out using a special stand, the so-called slot line. Binder content in the sandmix was determined by measurements of absorption damping Ad and insertion losses IL of electromagnetic wave. One of main advantages of the suggested new method of binder content measurement is short measuring time.

  5. MAIN PROBLEMS OF MOULDING OF SILUMINS. WAYS OF SOLUTION

    Directory of Open Access Journals (Sweden)

    E. I. Marukovich

    2016-01-01

    Full Text Available The main problems of silumin’ moulding are connected with insufficient modifying of casting structure, their considerable inclination to gas porosity, difficult to remove nonmetallic inclusions and these features are shown in the article. Protection of liquid silumin from influence of the air atmosphere; use of crucibles from aluminum oxide; refinement of fusion from nonmetallic inclusions and application of the accelerated hydrogen hardening of castings were used to solve these problems, as it is shown in the article.

  6. Production of press moulds by plasma spray forming process

    International Nuclear Information System (INIS)

    Borisov, Y.; Myakota, I.; Polyakov, S.

    2001-01-01

    Plasma spray forming process for production of press moulds which are used for manufacture of articles from plastics was developed. The press moulds were produced by plasma spraying of Cu-Al-Fe-alloy powder on surface of a master model. The master models were made from non-metallic materials with heat resistance below 70 C (wood, gypsum etc). Double cooling system which provides for a control of surface model temperature and quenching conditions of sprayed material was designed. It made possible on the one hand to support model surface temperature below 70 C and on the other hand to provide for temperature conditions of martensite transformation in Cu-Al-system with a fixation of metastable ductile α + β 1 -phase. This allowed to decrease residual stresses in sprayed layer (up to 0,5-2,5 MPa), to increase microhardness of the coating material (up to 1200-1800 MPa) and its ductility (σ B = 70-105 MPa, δ = 6-12 %). This plasma spray forming process makes possible to spray thick layers (5-20 mm and more) without their cracking and deformation. The process is used for a production of press moulds which are applied in shoes industry, for fabrication of toys, souvenirs etc. (author)

  7. Dose-associated changes in safety and efficacy parameters observed in a 24-week maintenance trial of olanzapine long-acting injection in patients with schizophrenia

    Directory of Open Access Journals (Sweden)

    Watson Susan B

    2011-02-01

    Full Text Available Abstract Background In a recently published 24-week maintenance study of olanzapine long-acting injection (LAI in schizophrenia (Kane et al., 2010, apparent dose-associated changes were noted in both efficacy and safety parameters. To help clinicians balance safety and efficacy when choosing a dose of olanzapine LAI, we further studied these changes. Methods Outpatients with schizophrenia who had maintained stability on open-label oral olanzapine for 4 to 8 weeks were randomly assigned to "low" (150 mg/2 weeks; N = 140, "medium" (405 mg/4 weeks; N = 318, or "high" (300 mg/2 weeks; N = 141 dosages of olanzapine LAI for 24 weeks. Potential relationships between dose and several safety or efficacy measures were examined via regression analysis, the Jonckheere-Terpstra test (continuous data, or the Cochran-Armitage test (categorical data. Results Safety parameters statistically significantly related to dose were mean weight change (low: +0.67 [SD = 4.38], medium: +0.89 [SD = 3.87], high: +1.70 [SD = 4.14] kg, p = .024; effect size [ES] = 0.264 high vs. low dose, mean change in prolactin (low: -5.61 [SD = 12.49], medium: -2.76 [SD = 19.02], high: +3.58 [SD = 33.78] μg/L, p = .001; ES = 0.410 high vs. low dose, fasting triglycerides change from normal at baseline to high (low: 3.2%, medium: 6.0%, high: 18.9%, p = .001; NNT = 7 high vs. low dose and fasting high-density lipoprotein cholesterol change from normal at baseline to low (low: 13.8%, medium: 19.6%, high: 30.7%, p = .019; NNT = 6 high vs. low dose. Efficacy measures significantly related to dose included Positive and Negative Syndrome Scale total score mean change (low: +2.66 [SD = 14.95], medium: -0.09 [SD = 13.47], high: -2.19 [SD = 13.11], p Conclusions Analyses of several safety and efficacy parameters revealed significant associations with dose of olanzapine LAI, with the highest dose generally showing greater efficacy as well as greater adverse changes in metabolic safety measures. When

  8. Three dimensions thermal-mechanical model of the billet in continuous casting petal-like mould

    International Nuclear Information System (INIS)

    Li Jing; Wu Li; Cao Zhiqiang; Tingju, L; Wang Tongmin

    2012-01-01

    Petal-like mould is a novel mould which has been applied to the steel industry in recent years. The behavior of the petal-like billet in continuous casting mould plays an important role in designing mould. It is hard to be in situ measured during continuous casting, however, can be worked out by the way of numerical simulation. But the research about the model of the billet in petal-like mould is very little. A 3D finite-element model has been built to simulate the thermal and stress fields of the molten steel in petal-like mould in this paper. The dynamic thermal boundary condition and the effect of ferrostatic pressure have been considered in the model. The temperature and stress in the billet have been predicted by this model.

  9. Isolation and identification mould micoflora inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java

    Directory of Open Access Journals (Sweden)

    MUHAMMAD ILYAS

    2007-04-01

    Full Text Available A study on isolation and identification mould inhabiting plant leaf litter had been conducted. The objective of the study was to isolate and identify mould inhabiting plant leaf litter from Mount Lawu, Surakarta, Central Java. The mould isolation was based on washing and filtering with membrane isolation method. The result showed that 39 moulds generas with 55 species varians, one group identified in class level, and three groups of unidentified mould isolates had been isolated. Taxas distributions showed that there were endophyte and phytopatogen mould isolates had been isolated such as Fusarium, Pestalotiopsis, Phoma, and Coelomycetes. However, typical soil taxa and common saprobic fungi such as Aspergillus, Cunninghamella, Mucor, Paecilomyces, Penicillium, Rhizopus, and Trichoderma remain dominated the resulted isolates.

  10. An Experimental Investigation to Facilitate an Improvement in the Design of an Electromagnetic Continuous Casting Mould

    Directory of Open Access Journals (Sweden)

    Lintao Zhang

    2016-04-01

    Full Text Available An electromagnetic continuous casting mould designed is proposed with a non-uniform slit distribution structure. This design has aimed to reduce the number of slits so that the mould’s strength is enhanced, whilst maintaining a similar metallurgy effect. In this paper, the metallurgy effect for the designed mould is investigated through the magnetic field distribution along the casting direction, the uniformity feature in the vicinity of the meniscus region, the temperature variation of the molten alloy pool and the mould wall. The results show that the designed mould achieved a similar effect as compared to the original mould; however, the configuration is simplified. This research highlights the topic of mould structure optimization, which would enable the Electromagnetic continuous casting (EMCC technique to be utilized with greater ease by industry.

  11. Possibilities of utilizing used moulding and core sands by microwave treatment

    Directory of Open Access Journals (Sweden)

    K. Granat

    2011-01-01

    Full Text Available The paper presents a semi-industrial reactor designed for microwave utilization of waste moulds and cores made of moulding sandsprepared in furane resin technology. It was found that a possibility exists of effective incinerating this way prepared residues of coresseparated from moulding sands or waste moulds left after casting. The preliminary tests evidenced that microwave heating is an effectiveway of disposing waste moulding sands and the applied apparatus permits effective control of the microwave heating process. The special structure permitting rotations of charge material and proper selection of the generators working cycles guarantee significant speeding-up the process and its full stabilisation. Application of microwave heating for utilization of waste moulds and cores containing synthetic resins as binders ensures significant and measurable economical benefits resulting from shorter process time.

  12. Plasma sprayed coatings on mild steel split moulds for uranium casting

    International Nuclear Information System (INIS)

    Sreekumar, K.P.; Padmanaban, P.V.A.; Venkatramani, N.; Singh, S.P.; Saha, D.P.; Date, V.G.

    2002-01-01

    High velocity high temperature plasma jets are used to deposit metals and ceramics on metallic substrates for oxidation and corrosion protection applications. Plasma sprayed ceramic coatings on metallic substrates are also used to prevent its reaction with molten metals. Metal-alumina duplex coatings on mild steel split moulds have been developed and successfully used for casting of uranium. Techno-economics of the coated moulds against the conventional graphite moulds are a major advantage. Mild steel moulds of 600 mm long and 75 mm in diameter have been plasma spray coated with alumina over a bond coat of molybdenum. In-plant tests showed an increase in number of castings per mould compared to the commonly used graphite moulds. (author)

  13. Gases Emission From Surface Layers of Sand Moulds and Cores Stored Under the Humid Air Conditions

    Directory of Open Access Journals (Sweden)

    Kaźnica N.

    2017-12-01

    Full Text Available A large number of defects of castings made in sand moulds is caused by gases. There are several sources of gases: gases emitted from moulds, cores or protective coatings during pouring and casting solidification; water in moulding sands; moisture adsorbed from surroundings due to atmospheric conditions changes. In investigations of gas volumetric emissions of moulding sands amounts of gases emitted from moulding sand were determined - up to now - in dependence of the applied binders, sand grains, protective coatings or alloys used for moulds pouring. The results of investigating gas volumetric emissions of thin-walled sand cores poured with liquid metal are presented in the hereby paper. They correspond to the surface layer in the mould work part, which is decisive for the surface quality of the obtained castings. In addition, cores were stored under conditions of a high air humidity, where due to large differences in humidity, the moisture - from surroundings - was adsorbed into the surface layer of the sand mould. Due to that, it was possible to asses the influence of the adsorbed moisture on the gas volumetric emission from moulds and cores surface layers by means of the new method of investigating the gas emission kinetics from thin moulding sand layers heated by liquid metal. The results of investigations of kinetics of the gas emission from moulding sands with furan and alkyd resins as well as with hydrated sodium silicate (water glass are presented. Kinetics of gases emissions from these kinds of moulding sands poured with Al-Si alloy were compared.

  14. Galactomyces geotrichum – moulds from dairy products with high biotechnological potential

    OpenAIRE

    Anna Grygier; Kamila Myszka; Magdalena Rudzińska

    2017-01-01

    The article reviews the properties of the Galactomyces geotrichum species, the mould that is most important for the dairy industry. G. geotrichum mould has been isolated from milk, cheeses and alcoholic beverage. Its presence in food products makes it possible to obtain a characteristic aroma and taste, which corresponds to the needs and preferences of consumers. G. geotrichum plays an important role in ecology, where the mould is employed for the degradation of various hazardous substances a...

  15. A 2D modeling approach for fluid propagation during FE-forming simulation of continuously reinforced composites in wet compression moulding

    Science.gov (United States)

    Poppe, Christian; Dörr, Dominik; Henning, Frank; Kärger, Luise

    2018-05-01

    Wet compression moulding (WCM) provides large-scale production potential for continuously fiber reinforced components as a promising alternative to resin transfer moulding (RTM). Lower cycle times are possible due to parallelization of the process steps draping, infiltration and curing during moulding (viscous draping). Experimental and theoretical investigations indicate a strong mutual dependency between the physical mechanisms, which occur during draping and mould filling (fluid-structure-interaction). Thus, key process parameters, like fiber orientation, fiber volume fraction, cavity pressure and the amount and viscosity of the resin are physically coupled. To enable time and cost efficient product and process development throughout all design stages, accurate process simulation tools are desirable. Separated draping and mould filling simulation models, as appropriate for the sequential RTM-process, cannot be applied for the WCM process due to the above outlined physical couplings. Within this study, a two-dimensional Darcy-Propagation-Element (DPE-2D) based on a finite element formulation with additional control volumes (FE/CV) is presented, verified and applied to forming simulation of a generic geometry, as a first step towards a fluid-structure-interaction model taking into account simultaneous resin infiltration and draping. The model is implemented in the commercial FE-Solver Abaqus by means of several user subroutines considering simultaneous draping and 2D-infiltration mechanisms. Darcy's equation is solved with respect to a local fiber orientation. Furthermore, the material model can access the local fluid domain properties to update the mechanical forming material parameter, which enables further investigations on the coupled physical mechanisms.

  16. Tribological evaluation for experimental design Al{sub 2}O{sub 3} obtained via low pressure injection moulding (LPIM); Avaliacao tribologica por planejamento experimental da Al{sub 2}O{sub 3} obtida via moldagem por injecao em baixa pressao (MIBP)

    Energy Technology Data Exchange (ETDEWEB)

    Dotta, A.L.B.; Costa, C.A.; Farias, M.C.M. [Universidade de Caxias do Sul (UCS), RS (Brazil); Cunha, M.A da, E-mail: alinebandotta@gmail.com [Universidade Federal do Rio Grande do Sul (UFRGS), Caxias do Sul, RS (Brazil)

    2016-07-01

    This work represents the tribological study of Al{sub 2}O{sub 3} obtained by LPIM using the experimental design technique to evaluate the interaction of the tribological parameters with the friction and wear. The LPIM process was performed at 90 °C for 24 h. The average friction coefficient for the factorial experimental design varied significantly with the load and the speed when Al{sub 2}O{sub 3} was tested with the steel counter body. In general, the wear coefficient was lower for the tribological pair Al{sub 2}O{sub 3}-steel, in which occurred the formation of an iron oxide tribofilm on the surface. As for the Al{sub 2}O{sub 3}-Al{sub 2}O{sub 3} pair, an intergranular fracture of the surface occurred, in addition to the presence of material adhered on the tracks. (author)

  17. Automated Layup of Sheet Prepregs on Complex Moulds

    OpenAIRE

    Elkington, Michael P; Ward, Carwyn; Potter, Kevin D

    2016-01-01

    A new two-stage method for the automated manufacture of high performance composites components is presented which aims to combine the capacity for forming complex shapes of Hand Layup with the speed of existing automated systems. In the first stage of the new process plies are formed into the approximate shape of the mould using a press mechanism. They are then passed onto a layup stage which uses multiple end effectors controlled by a single six axis robot to stick the plies down onto the mo...

  18. Testosterone Injection

    Science.gov (United States)

    ... typical male characteristics. Testosterone injection works by supplying synthetic testosterone to replace the testosterone that is normally ... as a pellet to be injected under the skin.Testosterone injection may control your symptoms but will ...

  19. Using special additions to preparation of the moulding mixture for casting steel parts of drive wheel type

    Science.gov (United States)

    Josan, A.; Pinca Bretotean, C.

    2015-06-01

    The paper presents the possibility of using special additions to the execution of moulding mixtures for steel castings, drive wheel type. Critical analysis of moulding technology leads to the idea that most defects appear due to using improper moulding mixture. Using a improper moulding mixture leads to penetration of steel in moulding mixture, resulting in the formation of adherences, due to inadequate refractarity of the mould and core mixtures. Using only the unique mixture to the moulding leads to increasing consumption of new sand, respectively to the increase of price of piece. Acording to the dates registered in the industrial practice is necessary to use the special additions to obtain the moulding mixtures, carbonaceous materials respectively.

  20. Intracavitary mould brachytherapy in malignant tumors of the maxilla

    International Nuclear Information System (INIS)

    Rosenblatt, Edward; Blumenfeld, Israel; Cederbaum, Martin; Kuten, Abraham

    1996-01-01

    Purpose: To integrate brachytherapy in the combined modality management of malignant tumors of the maxilla, as a means of increasing the radiotherapy dose to the tumor bed while avoiding high doses to the orbital contents. Materials and methods: Following a partial or total maxillectomy, a duplication of the interim surgical obturator was created using a wash of vinyl polysiloxane. This mould was used as a carrier for afterloading nylon catheters through which 192-Iridium seed-ribbons were inserted. Following brachytherapy, selected patients also received external beam irradiation. Results and discussion: After a median follow-up of 36 months, 9 out of 11 patients are alive and disease-free; 1 developed a local recurrence and another relapsed at another site in the oral cavity. Transient grade 1 - 2 mucositis at the implant site was observed in all patients. The review of computer isodose distributions showed that the average dose received by the homolateral eyeball was 10% (range 9,2 - 10.0) of the prescribed surface dose to the surgical cavity. Conclusions: Brachytherapy can be integrated in the management of patients with malignant tumors of the maxilla in the form of a custom-made intracavitary mould carrying 192-Iridium sources. We found this technique particularly useful in cases with close or positive surgical margins

  1. Habituation in non-neural organisms: evidence from slime moulds.

    Science.gov (United States)

    Boisseau, Romain P; Vogel, David; Dussutour, Audrey

    2016-04-27

    Learning, defined as a change in behaviour evoked by experience, has hitherto been investigated almost exclusively in multicellular neural organisms. Evidence for learning in non-neural multicellular organisms is scant, and only a few unequivocal reports of learning have been described in single-celled organisms. Here we demonstrate habituation, an unmistakable form of learning, in the non-neural organism Physarum polycephalum In our experiment, using chemotaxis as the behavioural output and quinine or caffeine as the stimulus, we showed that P. polycephalum learnt to ignore quinine or caffeine when the stimuli were repeated, but responded again when the stimulus was withheld for a certain time. Our results meet the principle criteria that have been used to demonstrate habituation: responsiveness decline and spontaneous recovery. To distinguish habituation from sensory adaptation or motor fatigue, we also show stimulus specificity. Our results point to the diversity of organisms lacking neurons, which likely display a hitherto unrecognized capacity for learning, and suggest that slime moulds may be an ideal model system in which to investigate fundamental mechanisms underlying learning processes. Besides, documenting learning in non-neural organisms such as slime moulds is centrally important to a comprehensive, phylogenetic understanding of when and where in the tree of life the earliest manifestations of learning evolved. © 2016 The Author(s).

  2. Casting Ductile Iron in Layer Moulds Made from Ecological Sands

    Directory of Open Access Journals (Sweden)

    M. Rączka

    2012-09-01

    Full Text Available The article contains the results of tests performed under the target project in Hardtop Foundry Charsznica.The objective of the tests and studies was to develop a technology of making high-quality ductile iron castings, combined witheffective means of environmental protection. The studies presented in this article related to castings weighing from 1 to 300 kg made from ductile iron of grades 400-15 and 500-7, using two-layer moulds, where the facing and core sand was the sand with an alkaline organic binder, while backing sand was the sand with an inorganic geopolymer binder.A simplified method of sand reclamation was applied with possible reuse of the reclaim as an addition to the backing sand. The castiron spheroidising treatment and inoculation were selected taking into account the specific conditions of Hardtop Foundry. A pilot batch of castings was made, testing the gating and feeding systems and using exothermic sleeves on risers. The study confirmed the validity of the adopted concept of making ductile iron castings in layer moulds, while maintaining the content of sand with an organic binder at a level of maximum 15%.

  3. Electroplating moulds using dry film thick negative photoresist

    Science.gov (United States)

    Kukharenka, E.; Farooqui, M. M.; Grigore, L.; Kraft, M.; Hollinshead, N.

    2003-07-01

    This paper reports on progress on the feasibility of fabricating moulds for electroplating using Ordyl P-50100 (negative) acrylate polymer based dry film photoresist, commercially available from Elga Europe (http://www.elgaeurope.it). We used this photoresist as an alternative to SU8 negative epoxy based photoresist, which is very difficult to process and remove after electroplating (Lorenz et al 1998 Microelectron. Eng. 41/42 371-4, Eyre et al 1998 Proc. MEMS'98 (Heidelberg) (Piscataway, NJ: IEEE) pp 218-22). Ordyl P-50100 is easy to work with and can be easily removed after processing. A single layer of Ordyl P-50100 was deposited by lamination up to 20 µm thickness. Thicker layers (200 µm and more) can be achieved with multilayer lamination using a manual laminator. For our applications we found that Ordyl P-50100 dry film photoresist is a very good alternative to SU8 for the realization of 100 µm high moulds. The results presented will open up new possibilities for low-cost LIGA-type processes for MEMS applications.

  4. Influence of Storage of Wet Arabica Parchment Prior to Wet Hulling on Moulds Development, OchratoxinA Contamination, and Cup Quality of Mandheling Coffee

    Directory of Open Access Journals (Sweden)

    Cahya Ismayadi

    2005-08-01

    Full Text Available Mandheling coffee has been a well known specialty coffees for decades and the demand for this coffee is currently increasing. This coffee is characterised by low acidity, heavy-complex body, spicy-little earthy and fruity flavor. Mandheling coffee is produced by smallholder farmers in the highland surrounding Lake TobaNorth Sumatra in an unique way i.e. following de-pulping and 1–2 days sundrying, wet parchment is stored for varying periods up to a few weeks, the parchments are then de-hulled when still wet (40–45% moisture content then the beans sundried. The handling procedure presumably contributes to the unique cup character of Mandheling coffee. On the other hand the storage of wet pachments may cause mould growth and mycotoxin contamination. This trial was designed to study the influence of storage of wet parchments prior to wet hulling on mould development, OTA contamination and cup Mandheling characteristic of the coffee product. The normal wet process, drying of parchment thoroughly to 12% moisture content was used as the control. Parchment coffees (6 lots used for this trial were drawn from farmers and collectors in the region. The wet parchments (41.74–53.96% moisture content were stored for 1 (D1, 7 (D7 and 14 (D14 days in PE sacks in a warehouse in the region. During the storage period, when there was visible mould growth, the parchments were spread on a plastic sheet inside the warehouse, as per common practice to suppress the mould growth. Following storage, the wet parchment was de-hulled and then sun-dried to a moisture content of 12% (MC12% or dried to a moisture content of 17%, and held in storage for 3 weeks prior to final drying to 12% mc. The ‘normal wet process’ i.e. fresh-non stored parchments dried thoroughly to 12%, were used as the control. Parameters measured were visual evaluation, mould infestation, a w, moisture content (MC on the stored parchment; while for dried beans mould infestation, OTA content and

  5. Assessment of the possibility of utilisation of used ceramic moulds originated from the investment casting technology

    Directory of Open Access Journals (Sweden)

    M. Holtzer

    2009-04-01

    Full Text Available Review of wastes generated by investment casting technology and discussion on possibilities of disposal of the largest quantity waste from this technology - used ceramic mould is presented in the paper. Preliminary examinations of disintegration process of used ceramic mould conducted in various testing conditions were performed in the frame of presented research. Applied system of disintegration doesn’twarrant obtained material to be suitable for reuse in production of ceramic moulds. Investigations of the inter-phase boundary: ceramicmould-casting were performed to examine environmental harmfulness of used ceramic moulds. Additionally ecologic assessment of spentmoulds by means of it’s elution in the aspect of qualifying possibilities of it’s disposal were performed. Gained results qualify the waste from ceramic mould to storage in deposits for neutral wastes.

  6. Potential of the application of the modified polysaccharides water solutions as binders of moulding sands

    Directory of Open Access Journals (Sweden)

    K. Kaczmarska

    2015-10-01

    Full Text Available The results of preliminary tests of selected properties of the moulding sands with the binder in the form of a 5 % water solution of the sodium salt of carboxymethyl starch (with a degree of substitution (DS of 0,2 and 0,87 arepresented in this study. The moulding sand properties such as permeability, abrasion resistance, tensile and bendingstrength - after curing - are shown in series of tests. The cure process was conducted in a field of electromagnetic radiation within the microwave range. The effect of the microwave treatment on the moulding sand was evaporating of water (solvent in a binder and cross-linking of the polymeric binder. As a result the cured moulding sands with particular properties, essential in the context of its application in the mould technology in the foundry industry, were obtained.

  7. High-temperature expansion and knock-out properties of moulding sands with water glass

    Directory of Open Access Journals (Sweden)

    Major-Gabryś K.

    2007-01-01

    Full Text Available The article focuses on the topic of improving the knock-out properties of moulding sand with water glass and ester hardener. It is settled that the cause of worse knock-out properties of moulding sand can be brought by their thermal expansion in increased temperatures. There is a presentation of the influence of different additives, containing Al2O3, on moulding sands’ expansion in increased temperatures. Within the frames of research, there was an elaboration of the influence of authors own additive- Glassex, on the expansion phenomenon of moulding sands with water glass and ester hardener. It is concluded, that the new additive stops the expansion of moulding sands and as well it improves their knock-out properties.

  8. Clinical and instrumental evaluation of a cross-linked hyaluronic acid filler dermal injection: effects on nasolabial folds skin biophysical parameters and augmentation from a single-dose, monocentric, open-label trial.

    Science.gov (United States)

    Cameli, Norma; Mariano, Maria; Serio, Mirko; Berardesca, Enzo

    2016-10-01

    When a hyaluronic acid dermal device to fill soft tissues is chosen, efficacy, safety and durability are key concerns. This is an open-label prospective study to instrumentally evaluate the effects of HA filler dermal injection on nasolabial folds skin biophysical parameters and augmentation. A single Italian site treated female subjects aged 40-55, for nasolabial folds, with a single standardized injection. The outcome was evaluated with objective quantitative measurements after 90 (T1) and 180 days (T2) from the injection comparing to baseline (T0) by means of Corneometer (skin hydration measurement), Cutometer (skin elasticity measurement), and Visioface devices for digital and UV computerized image analysis. Secondary endpoints were safety assessment, subject investigator satisfaction with the intervention. Assessment of aesthetic results included photographic documentation. The computerized image analysis confirmed the clinical assessment showing statistically significant reduction in nasolabial folds both at T1 and T2. Visioface® indexes showed a marked and statistical significant response. An excellent profile of satisfaction of the product at T2 from investigators and patients was recorded. Skin hydration and elasticity did not show significant changes. In our study, a standardized HA filler dermal injection on nasolabial folds did not influence skin biophysical parameters such as skin hydration and elasticity. Nasolabial folds showed a persistent and significative response at T2 confirmed by instrumental evaluation. The tolerability and safety profile of the product was excellent.

  9. Effect of fuel injection parameters on combustion stability and emissions of a mineral diesel fueled partially premixed charge compression ignition (PCCI) engine

    International Nuclear Information System (INIS)

    Jain, Ayush; Singh, Akhilendra Pratap; Agarwal, Avinash Kumar

    2017-01-01

    Highlights: • NOx and PM emissions were lowest at 700 bar fuel injection pressure (FIP). • PCCI showed lower knocking than compression ignition combustion mode. • Increasing FIP reduced emissions of nitrogen oxides and smoke opacity in PCCI mode. • Increasing FIP reduced nucleation mode particle concentration. • Increasing FIP with advanced main injection timings improved PCCI combustion. - Abstract: This experimental study focuses on developing new combustion concept for compression ignition (CI) engines by achieving partially homogeneous charge, leading to low temperature combustion (LTC). Partially premixed charge compression ignition (PCCI) combustion is a single-stage phenomenon, with combustion shifting towards increasingly premixed combustion phase, resulting in lower in-cylinder temperatures. PCCI leads to relatively lower emissions of oxides of nitrogen (NOx) and particulate matter (PM) simultaneously. To investigate combustion, performance and emission characteristics of the PCCI engine, experiments were performed in a mineral diesel fueled single cylinder research engine, which was equipped with flexible fuel injection equipment (FIE). Effects of fuel injection pressure (FIP) were investigated by changing the FIP from 400 bar to 1000 bar. Experiments were carried out by varying start of main injection (SoMI) timings (from 12° to 24° before top dead center (bTDC)), when using single pilot injection. This experimental study included detailed investigations of particulate characteristics such as particulate number-size distribution using engine exhaust particle sizer (EEPS), particulate bound trace metal analysis using inductively coupled plasma-optical emission spectrometer (ICP-OES), and soot morphology using transmission electron microscopy (TEM). PCCI combustion improved with increasing FIP (up to 700 bar) due to superior fuel atomization however further increasing FIP deteriorated PCCI combustion and engine performance due to intense

  10. The diversity of moulds in the candied salak (Salacca edulis Reinw.

    Directory of Open Access Journals (Sweden)

    RATNA SETYANINGSIH

    2002-07-01

    Full Text Available The aims of this research were to identify moulds in candied fruit within three varieties of salak (i.e. sleman, gading and pondoh, and to know the effect of sugar concentration added, the time of storage, and additional of preservative chemical substance (benzoic acid for the diversity of moulds in candied salak. The isolation method of moulds was used direct plating. In order to determine the kind of moulds, which tolerance in sugar solution (osmotic pressure, the samples were put on the surface of glucose 25% peptone yeast-extract agar (GPYA medium, and then incubated at 30oC for seven days. After that the colony was transferred on potato dextrose agar (PDA and czapeks dox agar (CDA identification media. The results indicated that there were 10 different kind of moulds can be found in all samples, namely Aspergillus flavus, A, niger, A. versicolor, A. fumigatus, Aspergillus sp., Monilia sp., Mucor sp., Penicillium sp., Rhizopus sp. and Wallemia sp. In order to examine the influence of sugar concentration on the growth of moulds, the candied salaks were treated in different concentration. Candied salak with or without additional benzoic acid were treated with sugar concentration of 200 g/l, 250 g/l and 300 g/l. The highest concentration of sugar showed to lowest diversity of moulds for varieties of sleman and gading, conversely for variety of salak pondoh, the additional of high sugar concentration showed increase in their diversity. The diversity of moulds in day of seventh was smaller than the diversity of moulds in day of null. The concentration of benzoic acid (1 g/l confined the diversity of moulds.

  11. Microstructure, SDAS and Mechanical Properties of A356 alloy Castings Made in Sand and Granulated Blast Furnace Slag Moulds

    Directory of Open Access Journals (Sweden)

    Jinugu B. R.

    2017-03-01

    Full Text Available Investigations were carried out to ensure the granulated blast furnace (GBF slag as an alternative mould material in foundry industry by assessing the cast products structure property correlations. Sodium silicate-CO2 process was adopted for preparing the moulds. Three types of moulds were made with slag, silica sand individually and combination of these two with 10% sodium silicate and 20 seconds CO2 gassing time. A356 alloy castings were performed on these newly developed slag moulds. The cast products were investigated for its metallography and mechanical properties. Results reveal that cast products with good surface finish and without any defects were produced. Faster heat transfers in slag moulds enabled the cast products with fine and refined grain structured; and also, lower Secondary Dendrite Arm Spacing (SDAS values were observed than sand mould. Slag mould casting shows improved mechanical properties like hardness, compression, tensile and impact strength compared to sand mould castings. Two types of tensile fracture modes, namely cleavage pattern with flat surfaces representing Al−Si eutectic zone and the areas of broken Fe-rich intermetallic compounds which appear as flower-like morphology was observed in sand mould castings. In contrast, GBF slag mould castings exhibit majority in dimple fracture morphology with traces of cleavage fracture. Charpy impact fractured surfaces of sand mould castings shows both transgranular and intergranular fracture modes. Only intergranular fracture mode was noticed in both GBF slag and mixed mould castings.

  12. Enabling Lean Design Through Computer Aided Synthesis: The Injection Moulding Cooling Case

    NARCIS (Netherlands)

    Jauregui Becker, Juan Manuel; Wits, Wessel Willems

    2015-01-01

    This paper explores the application of Computer Aided Synthesis (CAS) to support the implementation of Set-Based Concurrent Engineering (SBCE) and Just In Time Decision Making (JIT-DM), which are considered as two of the cornerstones of the Lean Design method. Computer Aided Synthesis refers to a

  13. Incorporating lean thinking and life cycle assessment to reduce environmental impacts of plastic injection moulded products

    OpenAIRE

    Cheung, Wai Ming; Leong, Jun; Vichare, Parag

    2017-01-01

    In the last decades, environmental footprint of the product manufacture has emerged as an important public concern, causing manufacturers to re-assess their product’s environmental impacts. Responding to global outcry on global warming, world leaders have agreed to limit global temperature rise to less than 2°C above the temperature in pre-industrial times. As a result, governments and industrial leaders around the world have proposed a roadmap for 80% emissions reduction by 2050. The aim of ...

  14. A comparative study of metal and ceramic injection moulding for precision applications

    DEFF Research Database (Denmark)

    Islam, Aminul; Giannekas, Nikolaos; Marhöfer, David Maximilian

    2015-01-01

    the right material and process for the right application.With this motivation, the current paper systematically characterizes the PIM and CIM process and presents the process capabilities in terms of part shrinkage, surface replication, tolerance capability and morphological fidelity....

  15. Structure Distribution in Precise Cast Iron Moulded on Meltable Model

    Directory of Open Access Journals (Sweden)

    Skrbek B.

    2015-12-01

    Full Text Available Topic of this work is to compare metalurgy of cast irons poured into sand moulds and into shell molds at IEG Jihlava company and from it following differencies in structures of thin- and thick-walled castings. This work is dealing with investigation and experimental measurement on surfaces and sections suitable thin- and thick-walled investment castings at IEG Jihlava. Cast irons with flake graphite (grey cast iron and cast irons with spheroidal graphite (ductile cast iron. Both mechanical and physical properties are determined using calculations from as measured values of wall thicknesses L and Lu, Vickers hardness and remanent magnetism. Measurement results are discussed, findings are formulated and methods for castings metallurgical quality improvement are recommended finally.

  16. Electric moulding of dispersed lipid nanotubes into a nanofluidic device.

    Science.gov (United States)

    Frusawa, Hiroshi; Manabe, Tatsuhiko; Kagiyama, Eri; Hirano, Ken; Kameta, Naohiro; Masuda, Mitsutoshi; Shimizu, Toshimi

    2013-01-01

    Hydrophilic nanotubes formed by lipid molecules have potential applications as platforms for chemical or biological events occurring in an attolitre volume inside a hollow cylinder. Here, we have integrated the lipid nanotubes (LNTs) by applying an AC electric field via plug-in electrode needles placed above a substrate. The off-chip assembly method has the on-demand adjustability of an electrode configuration, enabling the dispersed LNT to be electrically moulded into a separate film of parallel LNT arrays in one-step. The fluorescence resonance energy transfer technique as well as the digital microscopy visualised the overall filling of gold nanoparticles up to the inner capacity of an LNT film by capillary action, thereby showing the potential of this flexible film for use as a high-throughput nanofluidic device where not only is the endo-signalling and product in each LNT multiplied but also the encapsulated objects are efficiently transported and reacted.

  17. Modeling of Flexible Polyurethane Foam Shrinkage for Bra Cup Moulding Process Control

    Directory of Open Access Journals (Sweden)

    Long Wu

    2018-04-01

    Full Text Available Nowadays, moulding technology has become a remarkable manufacturing process in the intimate apparel industry. Polyurethane (PU foam sheets are used to mould three-dimensional (3D seamless bra cups of various softness and shapes, which eliminate bulky seams and reduce production costs. However, it has been challenging to accurately and effectively control the moulding process and bra cup thickness. In this study, the theoretical mechanism of heat transfer and the thermal conductivity of PU foams are first examined. Experimental studies are carried out to investigate the changes in foam materials at various moulding conditions (viz., temperatures, and lengths of dwell time in terms of surface morphology and thickness by using electron and optical microscopy. Based on the theoretical and experimental investigations of the thermal conductivity of the foam materials, empirical equations of shrinkage ratio and thermal conduction of foam materials were established. A regression model to predict flexible PU foam shrinkage during the bra cup moulding process was formulated by using the Levenberg-Marquardt method of nonlinear least squares algorithm and verified for accuracy. This study therefore provides an effective approach that optimizes control of the bra cup moulding process and assures the ultimate quality and thickness of moulded foam cups.

  18. Flow Dynamics of green sand in the DISAMATIC moulding process using Discrete element method (DEM)

    International Nuclear Information System (INIS)

    Hovad, E; Walther, J H; Thorborg, J; Hattel, J H; Larsen, P

    2015-01-01

    The DISAMATIC casting process production of sand moulds is simulated with DEM (discrete element method). The main purpose is to simulate the dynamics of the flow of green sand, during the production of the sand mould with DEM. The sand shot is simulated, which is the first stage of the DISAMATIC casting process. Depending on the actual casting geometry the mould can be geometrically quite complex involving e.g. shadowing effects and this is directly reflected in the sand flow during the moulding process. In the present work a mould chamber with “ribs” at the walls is chosen as a baseline geometry to emulate some of these important conditions found in the real moulding process. The sand flow is simulated with the DEM and compared with corresponding video footages from the interior of the chamber during the moulding process. The effect of the rolling resistance and the static friction coefficient is analysed and discussed in relation to the experimental findings. (paper)

  19. Studies on mould growth and biomass production using waste banana peel.

    Science.gov (United States)

    Essien, J P; Akpan, E J; Essien, E P

    2005-09-01

    Hyphomycetous (Aspergillus fumigatus) and Phycomycetous (Mucor hiemalis) moulds were cultivated in vitro at room temperature (28 + 20 degrees C) to examined their growth and biomass production on waste banana peel agar (BPA) and broth (BPB) using commercial malt extract agar (MEA) and broth (MEB) as control. The moulds grew comparatively well on banana peel substrates. No significant difference (p > 0.05) in radial growth rates was observed between moulds cultivated on PBA and MEA, although growth rates on MEA were slightly better. Slight variations in sizes of asexual spores and reproductive hyphae were also observed between moulds grown on MEA and BPA. Smaller conidia and sporangiospores, and shorter aerial hyphae (conidiophores and sporangiophores) were noticed in moulds grown on BPA than on MEA. The biomass weight of the test moulds obtained after one month of incubation with BPB were only about 1.8 mg and 1.4 mg less than values recorded for A. fumigatus and M. hiemalis respectively, grown on MEB. The impressive performance of the moulds on banana peel substrate may be attributed to the rich nutrient (particularly the crude protein 7.8% and crude fat 11.6% contents) composition of banana peels. The value of this agricultural waste can therefore be increased by its use not only in the manufacture of mycological medium but also in the production of valuable microfungal biomass which is rich in protein and fatty acids.

  20. Grains colonised by moulds: fungal identification and headspace analysis of produced volatile metabolites

    Directory of Open Access Journals (Sweden)

    Maria Paola Tampieri

    2010-01-01

    Full Text Available The aim of this work was to verify if the headspace analysis of fungal volatile compounds produced by some species of Fusarium can be used as a marker of mould presence on maize. Eight samples of maize (four yellow maize from North Italy and four white maize from Hungary, naturally contaminated by Fusarium and positive for the presence of fumonisins, were analyzed to detect moisture content, Aw, volatile metabolites and an enumeration of viable moulds was performed by means of a colony count technique. Headspace samples were analysed using a gas-chromatograph equipped with a capillary column TR-WAX to detect volatile metabolites of moulds. Furthermore macro and microscopic examination of the colonies was performed in order to distinguish, according to their morphology, the genera of the prevalent present moulds. Prevalent mould of eight samples was Fusarium, but other fungi, like Aspergillus, Penicillum and Mucoraceae, were observed. The metabolites produced by F.graminearum and F. moniliforme were Isobutyl-acetate, 3-Methyl-1-butanol and, only at 8 days, 3-Octanone. The incubation time can affect off flavour production in consequence of the presence of other moulds. Further studies on maize samples under different conditions are needed in order to establish the presence of moulds using the count technique and through the identification of volatile compounds.

  1. Myceliophthora thermophila syn. Sporotrichum thermophile: a thermophilic mould of biotechnological potential.

    Science.gov (United States)

    Singh, Bijender

    2016-01-01

    Myceliophthora thermophila syn. Sporotrichum thermophile is a ubiquitous thermophilic mould with a strong ability to degrade organic matter during optimal growth at 45 °C. Both genome analysis and experimental data have suggested that the mould is capable of hydrolyzing all major polysaccharides found in biomass. The mould is able to secrete a large number of hydrolytic enzymes (cellulases, laccases, xylanases, pectinases, lipases, phytases and some other miscellaneous enzymes) employed in various biotechnological applications. Characterization of the biomass-hydrolyzing activity of wild and recombinant enzymes suggests that this mould is highly efficient in biomass decomposition at both moderate and high temperatures. The native enzymes produced by the mould are more efficient in activity than their mesophilic counterparts beside their low enzyme titers. The mould is able to synthesize various biomolecules, which are used in multifarious applications. Genome sequence data of M. thermophila also supported the physiological data. This review describes the biotechnological potential of thermophilic mould, M. thermophila supported by genomic and experimental evidences.

  2. Virtual analysis of influence of a filter on mould filling

    Directory of Open Access Journals (Sweden)

    Zhian Xu

    2011-11-01

    Full Text Available Ceramic filters are used to avoid slag and impurities in foundry applications. When not properly applied, the presence of these filters may have a significant influence on mould filling. 3-D casting simulation has been applied to study the effects of the use of a ceramic filter on the metal flow in a gating system. Instead of using a pressure drop model to represent the behaviour of a fluid metal flow passing through a filter, a real exact filter geometry, which is created by a high resolution CT-scan and a non-destructive imaging technique, in the gating system is applied in the simulation. In this research, nodular cast iron is poured into a block casting. A depressurized gating system is used. After a choke, a filter with different orientations is placed in the system. Mould filling coupled with temperature is simulated. Geometries using different orientations of the filter, and without the filter have been researched. The simulated results show that the filter has no influence on the pouring time of the casting if the choke section is small enough compared to the effective section of the filter. Although the filter has no significant influence on the flow patterns in the block casting itself, the flow patterns in the filter zone are different. When the liquid metal passes a horizontal filter, it will be broken into many small streams and show a shower effect. After the part under the filter is full, the shower effect disappears. When the filter is located at the vertical position, due to the gravity, the shower effect is less. If no filter presents on the system, the liquid metal passes through the filter zone with a high speed and causes surface turbulence.

  3. Cellular automaton model of crowd evacuation inspired by slime mould

    Science.gov (United States)

    Kalogeiton, V. S.; Papadopoulos, D. P.; Georgilas, I. P.; Sirakoulis, G. Ch.; Adamatzky, A. I.

    2015-04-01

    In all the living organisms, the self-preservation behaviour is almost universal. Even the most simple of living organisms, like slime mould, is typically under intense selective pressure to evolve a response to ensure their evolution and safety in the best possible way. On the other hand, evacuation of a place can be easily characterized as one of the most stressful situations for the individuals taking part on it. Taking inspiration from the slime mould behaviour, we are introducing a computational bio-inspired model crowd evacuation model. Cellular Automata (CA) were selected as a fully parallel advanced computation tool able to mimic the Physarum's behaviour. In particular, the proposed CA model takes into account while mimicking the Physarum foraging process, the food diffusion, the organism's growth, the creation of tubes for each organism, the selection of optimum tube for each human in correspondence to the crowd evacuation under study and finally, the movement of all humans at each time step towards near exit. To test the model's efficiency and robustness, several simulation scenarios were proposed both in virtual and real-life indoor environments (namely, the first floor of office building B of the Department of Electrical and Computer Engineering of Democritus University of Thrace). The proposed model is further evaluated in a purely quantitative way by comparing the simulation results with the corresponding ones from the bibliography taken by real data. The examined fundamental diagrams of velocity-density and flow-density are found in full agreement with many of the already published corresponding results proving the adequacy, the fitness and the resulting dynamics of the model. Finally, several real Physarum experiments were conducted in an archetype of the aforementioned real-life environment proving at last that the proposed model succeeded in reproducing sufficiently the Physarum's recorded behaviour derived from observation of the aforementioned

  4. Rate of solidification of aluminium casting in varying wall thickness of cylindrical metallic moulds

    Directory of Open Access Journals (Sweden)

    Katsina Christopher BALA

    2014-02-01

    Full Text Available The quality of final casting mainly depends on the rate of solidification as rapid solidification produces fine grains structures with better mechanical properties. The analysis of heat transfer during the casting and solidification of aluminium alloy as well as the experimental investigation of the rate of solidification in varying thicknesses of cylindrical metallic mould was carried out. The temperature variation with time of the casting was recorded from which cooling curves were obtained for the determination of solidification time of the cast. The results showed that as the cylindrical mould thickness increases the solidification time decreases due to the chilling effect of the mould.

  5. Effectiveness of Protective Action of Coatings from Moisture Sorption into Surface Layer of Sand Moulds

    Directory of Open Access Journals (Sweden)

    Kaźnica N.

    2016-12-01

    Full Text Available The results of investigations of the sorption process of surface layers of sand moulds covered by zirconium and zirconium - graphite alcohol coatings are presented in the paper. Investigations comprised two kinds of sand grains (silica sand and reclaimed sand of moulding sand with furan resin. Tests were performed under conditions of a high relative air humidity 75 - 85% and a constant temperature within the range 28 – 33°C. To evaluate the effectiveness of coatings protective action from moisture penetration into surface layers of sand moulds gravimetric method of quantitavie moisture sorption and ultrasonic method were applied in measurements.

  6. Thermal Conductivity of Moulding Sand with Chemical Binders, Attempts of its Increasing

    Directory of Open Access Journals (Sweden)

    Zych J.

    2015-04-01

    Full Text Available The investigation results of the thermal conductivity of the selected group of moulding sands with chemical binders, mainly organic, are presented in the hereby paper. Studies encompassed also moulding sands into which additions improving the thermal conductivity were introduced. Two testing methods were applied, i.e. investigations at a steady and unsteady temperature zone. For investigations at a steady temperature zone the new original experimental stand was designed and built, adapted also for testing moulding sands with binders undergoing destruction at relatively low temperatures.

  7. Plaster: its influence on the behaviour of mould surface in the gluing process

    International Nuclear Information System (INIS)

    Jordao, M.A.P.; Goulart, E.P.; Souza, D.D.D. de; Kiyohara, P.K.

    1989-01-01

    Plaster is an important auxiliary raw material in ceramics, but the industry in Brazil use to give litle importance to its properties. The IPT Ceramic Department initiated studies to upgrade local knowledge on this material. In this paper, the following already studied topics are presented. Characterization of α and β plaster powder, by X-ray diffraction, optical and scanning electron microscopy, specific gravity and surface are (BET). Influence of the plaster/water ratio on the mould characteristics by X-ray diffraction, scanning electron microscopy, porosity and permeability. Behavior of the plaster mould surface against the moulded surface after several aluminum oxide splip castings by scanning electron microscopy [pt

  8. Granisetron Injection

    Science.gov (United States)

    Granisetron immediate-release injection is used to prevent nausea and vomiting caused by cancer chemotherapy and to ... nausea and vomiting that may occur after surgery. Granisetron extended-release (long-acting) injection is used with ...

  9. Edaravone Injection

    Science.gov (United States)

    Edaravone injection is used to treat amyotrophic lateral sclerosis (ALS, Lou Gehrig's disease; a condition in which ... die, causing the muscles to shrink and weaken). Edaravone injection is in a class of medications called ...

  10. Meropenem Injection

    Science.gov (United States)

    ... injection is in a class of medications called antibiotics. It works by killing bacteria that cause infection.Antibiotics such as meropenem injection will not work for colds, flu, or other viral infections. Taking ...

  11. Chloramphenicol Injection

    Science.gov (United States)

    ... injection is in a class of medications called antibiotics. It works by stopping the growth of bacteria..Antibiotics such as chloramphenicol injection will not work for colds, flu, or other viral infections. Taking ...

  12. Colistimethate Injection

    Science.gov (United States)

    ... injection is in a class of medications called antibiotics. It works by killing bacteria.Antibiotics such as colistimethate injection will not work for colds, flu, or other viral infections. Using ...

  13. Defibrotide Injection

    Science.gov (United States)

    Defibrotide injection is used to treat adults and children with hepatic veno-occlusive disease (VOD; blocked blood ... the body and then returned to the body). Defibrotide injection is in a class of medications called ...

  14. Nalbuphine Injection

    Science.gov (United States)

    ... injection is in a class of medications called opioid agonist-antagonists. It works by changing the way ... suddenly stop using nalbuphine injection, you may experience withdrawal symptoms including restlessness; teary eyes; runny nose; yawning; ...

  15. Fibre Length Reduction in Natural Fibre-Reinforced Polymers during Compounding and Injection Moulding—Experiments Versus Numerical Prediction of Fibre Breakage

    Directory of Open Access Journals (Sweden)

    Katharina Albrecht

    2018-03-01

    Full Text Available To establish injection-moulded, natural fibre-reinforced polymers in the automotive industry, numerical simulations are important. To include the breakage behaviour of natural fibres in simulations, a profound understanding is necessary. In this study, the length and width reduction of flax and sisal fibre bundles were analysed experimentally during compounding and injection moulding. Further an optical analysis of the fibre breakage behaviour was performed via scanning electron microscopy and during fibre tensile testing with an ultra-high-speed camera. The fibre breakage of flax and sisal during injection moulding was modelled using a micromechanical model. The experimental and simulative results consistently show that during injection moulding the fibre length is not reduced further; the fibre length was already significantly reduced during compounding. For the mechanical properties of a fibre-reinforced composite it is important to overachieve the critical fibre length in the injection moulded component. The micromechanical model could be used to predict the necessary fibre length in the granules.

  16. Effect of parameters of high-pressure die casting on occurrence of casting nonconformities in sleeves of silumin alloy EN AB 47100

    Directory of Open Access Journals (Sweden)

    Pałyga Ł.

    2017-03-01

    Full Text Available The paper presents a research on the effect of extreme - for the technology of the considered silumin EN AB 47100 - parameters of high-pressure die casting on occurrence of casting nonconformities. Considered was influence of the way of assembling the mould cooled-down to 140-160°C, non-standard for the selected casting, and pouring temperature in the range of 705 to 720°C (higher than the recommended of non-refined alloy. The castings were prepared with use of a high-pressure casting machine made by Kirov with mould closing force of 2500 kN. Occurrence of nonconformities was evaluated on properly prepared specimens taken from the castings manufactured with various parameters of the injection piston and various multiplication pressures. The results were subjected to quantitative and qualitative analyses of casting nonconformities and distribution of major alloying elements. It was found that proper selection of working parameters of the casting machine, in spite of disadvantageous pouring conditions, makes it possible to reduce occurrence of some casting defects, like shrinkage cavities and porosity, to improve tightness of castings even when the alloy refining process is omitted.

  17. Influence of the Reclaim Addition on Properties of Moulding Sands with the Geopol Binder

    Directory of Open Access Journals (Sweden)

    Drożyński D.

    2015-03-01

    Full Text Available The investigation results of the influence of the reclaim additions on the properties of moulding sands with the GEOPOL geopolymer binder developed by the SAND TEAM Company were presented. Two brands of hardeners were applied in the tested compositions, the first one was developed by the SAND TEAM Company, marked SA72 and the new hardener offered by the KRATOS Company, marked KR72. The main purpose of investigations was to determine the influence of reclaim fractions and the applied hardener on the basic moulding sands properties, such as: bending and tensile strength, permeability and grindability. The unfavourable influence of the reclaim additions into moulding sands on the tested properties as well as an increased hardening rate, were found. Moulding sands, in which the hardener KR72 of the KRATOS Company was used, were less sensitive to the reclaim additions

  18. Effects of mould on electrochemical migration behaviour of immersion silver finished printed circuit board.

    Science.gov (United States)

    Yi, Pan; Xiao, Kui; Dong, Chaofang; Zou, Shiwen; Li, Xiaogang

    2018-02-01

    The role played by mould in the electrochemical migration (ECM) behaviour of an immersion silver finished printed circuit board (PCB-ImAg) under a direct current (DC) bias was investigated. An interesting phenomenon is found whereby mould, especially Aspergillus niger, can preferentially grow well on PCB-ImAg under electrical bias and then bridge integrated circuits and form a migration path. The cooperation of the mould and DC bias aggravates the ECM process occurring on PCB-ImAg. When the bias voltage is below 15V, ECM almost does not occur for Ag coating. Mechanisms that explain the ECM processes of PCB-ImAg in the presence of mould and DC bias are proposed. Copyright © 2017. Published by Elsevier B.V.

  19. Modelling the effect of ethanol on growth rate of food spoilage moulds

    NARCIS (Netherlands)

    Dantigny, P.; Guilmart, A.; Radoi, F.; Bensoussan, M.; Zwietering, M.H.

    2005-01-01

    The effect of ethanol (E) on the radial growth rate (¿) of food spoilage moulds (Aspergillus candidus, Aspergillus flavus, Aspergillus niger, Cladosporium cladosporioides, Eurotium herbariorum, Mucor circinelloides, Mucor racemosus, Paecilomyces variotii, Penicillium chrysogenum, Penicillium

  20. Inhibitory Properties of Lactic Acid Bacteria against Moulds Associated with Spoilage of Bakery Products

    OpenAIRE

    I. A. Adesina; A. O. Ojokoh; D. J. Arotupin

    2017-01-01

    Aim: To evaluate the potentiality of LAB strains isolated from different fermented products to inhibit moulds associated with spoilage of bakery products. Methodology: Lactic acid bacterial (LAB) strains obtained from fermented products (“burukutu”, “pito”, yoghurt, and “iru”) were screened for antifungal activity against moulds (Aspergillus flavus, Aspergillus fumigatus, Aspergillus repens and Penicillium sp.) isolated from spoilt bakery products. Inhibitory activities of the lactic acid...

  1. Manuscript title: antifungal proteins from moulds: analytical tools and potential application to dry-ripened foods.

    Science.gov (United States)

    Delgado, Josué; Owens, Rebecca A; Doyle, Sean; Asensio, Miguel A; Núñez, Félix

    2016-08-01

    Moulds growing on the surface of dry-ripened foods contribute to their sensory qualities, but some of them are able to produce mycotoxins that pose a hazard to consumers. Small cysteine-rich antifungal proteins (AFPs) from moulds are highly stable to pH and proteolysis and exhibit a broad inhibition spectrum against filamentous fungi, providing new chances to control hazardous moulds in fermented foods. The analytical tools for characterizing the cellular targets and affected pathways are reviewed. Strategies currently employed to study these mechanisms of action include 'omics' approaches that have come to the forefront in recent years, developing in tandem with genome sequencing of relevant organisms. These techniques contribute to a better understanding of the response of moulds against AFPs, allowing the design of complementary strategies to maximize or overcome the limitations of using AFPs on foods. AFPs alter chitin biosynthesis, and some fungi react inducing cell wall integrity (CWI) pathway. However, moulds able to increase chitin content at the cell wall by increasing proteins in either CWI or calmodulin-calcineurin signalling pathways will resist AFPs. Similarly, AFPs increase the intracellular levels of reactive oxygen species (ROS), and moulds increasing G-protein complex β subunit CpcB and/or enzymes to efficiently produce glutathione may evade apoptosis. Unknown aspects that need to be addressed include the interaction with mycotoxin production by less sensitive toxigenic moulds. However, significant steps have been taken to encourage the use of AFPs in intermediate-moisture foods, particularly for mould-ripened cheese and meat products.

  2. The presence of undesirable mould species on the surface of dry sausages

    Directory of Open Access Journals (Sweden)

    Vesković-Moračanin Slavica M.

    2008-01-01

    Full Text Available Transition from manufacture to the industrial way of meat production and processing, as well as contemporary concept of food quality and safety, have led to the application of starter cultures. Their application leads towards the streamlining of the production process in the desired direction, quality improvement and its harmonization, and thereby to its standardization. Application of moulds in the meat industry is based on positive effects of their proteolytic and lipolytic egzoenzymes which, as a consequence, leads to the creation of characteristic sensory properties ('flavor' of fermented products. Penicillium nalgiovense is a typical representative of moulds used in the production of fermented sausages-salamis from our region. Samples of 'zimska salama' (dry sausage, produced with Penicillium nalgiovense, were evaluated as hygienically unacceptable. Their sensory properties changed due to contamination of this mould during the ripening process. Micological analysis discovered the presence of Penicillium aurantiogriseum, which is a frequent mould contaminant in the meat industry. At the same time, thin layer chromatography revealed no possibility of metabolic activity of this mould in the creation of mycotoxins. However, the presence of this mould on the surface of 'zimska salama' is considered as undesirable due to formation of 'off flavor' in products. Such product is considered as hygienically unacceptable and cannot be used for the human consumption.

  3. Study on the Mould-Resistant Properties of Moso Bamboo Treated with High Pressure and Amylase

    Directory of Open Access Journals (Sweden)

    Xiao-Dong Huang

    2013-11-01

    Full Text Available Starch of moso bamboo mainly exists in the elongated parenchyma cells, and it is difficult for amylase to enter moso bamboo and dissolve the starch. Therefore, the mould resistance capability of moso bamboo’s products cannot meet the need for bamboo to resist fungal decay. In this experiment, moso bamboo blocks were first treated at six levels of pressure and for six different treatment durations. The results showed that reducing sugar content was decreased dramatically from 0.92 mg/L to 0.19 mg/L and the starch content decreased from 1.18% to 0.96% when the pressure was increased from 0 psi to 100 psi. Regression analysis showed that the effects of an individual amylase reaction and individual pressure treatment on the starch or reducing sugar content were significant with a high correlation coefficient. Three traditional types of moso bamboo moulds (Aspergillus niger, Penicillium citrinum, and Trichoderma viride were then used for mould resistance testing. The results revealed that the mould resistance capability of moso bamboo blocks could be greatly improved by the combined effect of enzyme activity and pressure treatment. Mould resistance was enhanced by increasing the pressure or prolonging the treatment time. This research could provide a new method for the protection of bamboo from mould attack.

  4. Origanum dictamnus Oil Vapour Suppresses the Development of Grey Mould in Eggplant Fruit In Vitro

    Science.gov (United States)

    Loulakakis, Kostas; Magan, Naresh; Tzortzakis, Nikos

    2014-01-01

    Grey mould rot (Botrytis cinerea) development in vitro or in eggplant (Solanum melongena L.) fruit was evaluated after treatment with dittany (Origanum dictamnus L.) oil (DIT) and storage at 12°C and 95% relative humidity during or following exposure to the volatiles. DIT volatiles used in different concentration (0-50-100-250 μL/L) and times of exposure (up to 120 h) examined the effects on pathogen development as well as fruit quality parameters. In vitro, fungal colony growth was inhibited with the application of DIT oil (during or after exposure) and/or time of application. Continuous exposure to oils reduced conidial germination and production with fungistatic effects observed in 250 μL/L. In vivo, fungal lesion growth and conidial production reduced in DIT-treated fruits. Interesting, in fruits preexposed to volatiles before fungal inoculation, DIT application induced fruit resistance against the pathogen, by reduced lesion growth and conidial production. Conidial viability reduced in >100 μL/L DIT oil. Fruits exposed to essential oil did not affect fruit quality related attributes in general, while skin lightness (L value) increased in 50 and 100 μL/L DIT oil. The results of the current study indicated that dittany volatiles may be considered as an alternative food preservative, eliminating disease spread in the storage/transit atmospheres. PMID:25254209

  5. Origanum dictamnus Oil Vapour Suppresses the Development of Grey Mould in Eggplant Fruit In Vitro

    Directory of Open Access Journals (Sweden)

    Andriana Stavropoulou

    2014-01-01

    Full Text Available Grey mould rot (Botrytis cinerea development in vitro or in eggplant (Solanum melongena L. fruit was evaluated after treatment with dittany (Origanum dictamnus L. oil (DIT and storage at 12°C and 95% relative humidity during or following exposure to the volatiles. DIT volatiles used in different concentration (0-50-100-250 μL/L and times of exposure (up to 120 h examined the effects on pathogen development as well as fruit quality parameters. In vitro, fungal colony growth was inhibited with the application of DIT oil (during or after exposure and/or time of application. Continuous exposure to oils reduced conidial germination and production with fungistatic effects observed in 250 μL/L. In vivo, fungal lesion growth and conidial production reduced in DIT-treated fruits. Interesting, in fruits preexposed to volatiles before fungal inoculation, DIT application induced fruit resistance against the pathogen, by reduced lesion growth and conidial production. Conidial viability reduced in >100 μL/L DIT oil. Fruits exposed to essential oil did not affect fruit quality related attributes in general, while skin lightness (L value increased in 50 and 100 μL/L DIT oil. The results of the current study indicated that dittany volatiles may be considered as an alternative food preservative, eliminating disease spread in the storage/transit atmospheres.

  6. Reengineering of Permanent Mould Casting with Lean Manufacturing Methods

    Directory of Open Access Journals (Sweden)

    R. Władysiak

    2007-07-01

    Full Text Available At the work were introduced main areas of production system project of casts produced in permanent moulds, that constitutes reengineering of conventional production system according to Lean Manufacturing (LM methods. New resolution of cooling of dies with water mist was shown to casting of car wheels made from aluminium alloys in low pressure casting process. It was implemented as a part of goal-oriented project in R.H. Alurad Sp.z o.o. in Gorzyce. Its using intensifies solidification and self-cooling of casts shortening the time of casting cycle by the 30%. It was described reorganizing casting stations into multi-machines cells production and the process of their fast tool’s exchange with applying the SMED method. A project of the system was described controlling the production of the foundry with the computer aided light Kanban system. A visualization of the process was shown the production of casts with use the value stream mapping method. They proved that applying casting new method in the technology and LM methods allowed to eliminate down-times, to reduce the level of stocks, to increase the productivity and the flow of the castings production.

  7. Error analysis in predictive modelling demonstrated on mould data.

    Science.gov (United States)

    Baranyi, József; Csernus, Olívia; Beczner, Judit

    2014-01-17

    The purpose of this paper was to develop a predictive model for the effect of temperature and water activity on the growth rate of Aspergillus niger and to determine the sources of the error when the model is used for prediction. Parallel mould growth curves, derived from the same spore batch, were generated and fitted to determine their growth rate. The variances of replicate ln(growth-rate) estimates were used to quantify the experimental variability, inherent to the method of determining the growth rate. The environmental variability was quantified by the variance of the respective means of replicates. The idea is analogous to the "within group" and "between groups" variability concepts of ANOVA procedures. A (secondary) model, with temperature and water activity as explanatory variables, was fitted to the natural logarithm of the growth rates determined by the primary model. The model error and the experimental and environmental errors were ranked according to their contribution to the total error of prediction. Our method can readily be applied to analysing the error structure of predictive models of bacterial growth models, too. © 2013.

  8. Birefringence in heat-mechanical modified freshly moulded polyester fibers

    Energy Technology Data Exchange (ETDEWEB)

    Velev, V; Dimov, T; Popov, A; Denev, Y; Hristov, H; Angelov, T; Markova, K; Zagortcheva, M; Arhangelova, N; Uzunov, N, E-mail: v.velev@shu-bg.ne

    2010-11-01

    The article submits new experimental data concerning to the role of combined thermo-mechanical treatments on the structural development of freshly moulded uncrystallized but crystallizable poly (ethylene terephthalate) (PET) fibers. The object of the present work is PET as a thermoplastic polymer with a large practical application. The report is devoted to the influence of the heat-mechanical modification temperature on the structure rearrangement in uniaxially orientated amorphous PET. The heat-mechanical modification of the investigated yarns and the optical measurements were realized by specialized gears constructed and built in the author's laboratories. The fibers heat-mechanical modification includes samples annealing at constant temperature above their glass transition temperature (T{sub g}) without strain stress. The yarn annealing has been followed from well defined uniaxially strain-loading with values from 0 MPa up to 30 MPa during two minutes. The optical measurements were carried out by an optical system using a polarization microscope and a CCD camera. The obtained experimental data has been analyzed by Mocha-1.2 (Jandel Scientific) software. There are established dependences between the heat-mechanical modification mode and the structural rearrangements running in the studied PET samples.

  9. Dimensional measurement of micro-moulded parts by computed tomography

    DEFF Research Database (Denmark)

    Ontiveros, S.; Yagüe-Fabra, J.A.; Jiménez, R.

    2012-01-01

    Computed tomography (CT) is progressively assuming an important role in metrology applications and great efforts are being made in order to turn it into a reliable and standardized measuring technology. CT is typically used for non-destructive tests, but it is currently becoming very popular for ...... and the analysis of the results provide valuable conclusions about the advantages and drawbacks of using CT metrology in comparison with other measuring systems when these techniques are employed for the quality control of micro-moulded parts.......Computed tomography (CT) is progressively assuming an important role in metrology applications and great efforts are being made in order to turn it into a reliable and standardized measuring technology. CT is typically used for non-destructive tests, but it is currently becoming very popular...... for dimensional metrology applications due to its strategic advantages such as the capability of performing measurements on both the component's surface and volume, allowing inspection possibilities to otherwise non-accessible internal features. This paper focuses on the dimensional verification of two micro...

  10. Comparison of two setups for induction heating in injection molding

    DEFF Research Database (Denmark)

    Menotti, Stefano; Hansen, Hans Nørgaard; Bissacco, Giuliano

    2015-01-01

    To eliminate defects and improve the quality of molded parts, increasing the mold temperature is one of the applicable solutions. A high mold temperature can increase the path flow of the polymer inside the cavity allowing reduction of the number of injection points, reduction of part thickness......, and moulding of smaller and more complex geometries. The last two aspects are very important in micro injection molding. In this paper, a new embedded induction heating system is proposed and validated and two different coil setups were tested and compared. An experimental investigation was performed based...

  11. Growth performance parameters, bone calcification and immune response of in ovo injection of 25-hydroxycholecalciferol and vitamin K3 in male ross 308 broilers.

    Science.gov (United States)

    Abbasi, Tahereh; Shakeri, Malak; Zaghari, Mojtaba; Kohram, Hamid

    2017-03-01

    This experiment aimed to evaluate the effects of in ovo injection of 25-hydroxycholecalciferol (25-OH-D 3 ) and Vitamin K 3 on growth performance, bone calcification and immune system responses in male Ross 308 broilers. Twelve treatment groups with a total number of 768 experimental hatching eggs, four replications and 16 eggs in each replication were selected to form a completely randomized design of factorial arrangement. Treatments included: (1) distilled water, (2) 0.4 μg D 3 , (3) 0.4 μg D 3  + 2 μg K 3 , (4) 0.4 μg D 3  + 6 μg K 3 , (5) 0.6 μg D 3 , (6) 0.6 μg D 3  + 2 μg K 3 , (7) 0.6 μg D 3  + 6 μg K 3 , (8) 0.8 μg D 3 , (9) 0.8 μg D 3  + 2 μg K 3 , (10) 0.8 μg D 3  + 6 μg K 3 , (11) 2 μg K 3 and (12) 6 μg K 3 . Eggs were transferred to corresponding hatching baskets on the 18th day of incubation and received 0.5 ml of experimental solutions specific to each treatment. The results of our experiments showed that Treatment No. 4 ranked the best out of those administered; holding the highest level of weight gain, feed intake during the breeding period (grower and finisher), bone calcium and phosphorus concentration, and tibia fractural force, (p Vitamins D 3 and K 3 in ovo injection has beneficial effects on growth performance, immune system and bone development. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. The Impact of in ovo Injection of Silver Nanoparticles, Thyme and Savory Extracts in Broiler Breeder eggs on Growth Performance, Lymphoid-Organ Weights, and Blood and Immune Parameters of Broiler Chicks

    Directory of Open Access Journals (Sweden)

    Saki AA

    2015-12-01

    Full Text Available This study was conducted to evaluate the long-term effects of in ovo injection of nano-silver, thyme and savory extracts in broiler breeder eggs on growth performance, lymphoid organ weights, immune and blood parameters and bone mineral concentration of broiler chicks. A total of 560 fertilized broiler breeder eggs were divided into 7 groups. On d 5 of incubation, eggs were treated with the following groups. Group 1 (control, no injection; group 2 (placebo, 1 mL of 0.9% NaCl; group 3 and 4 (placebo + 30 and 45 mg of nano-silver, respectively; group 5 and 6 (placebo + 75 and 100 mg of thyme, respectively and group 7 (placebo + 75 mg of savory. After hatch, chickens were fed a corn-soybean meal diet under the controlled conditions and slaughtered at 14 and 21 d of age for sample collection and analysis. The lymphoid-organ weights and growth rate were not affected by dietary treatments at 14 and 21 d of age. The results also showed that nano-silver injected into broiler breeder eggs during incubation improved the bone mineral concentration and cell-mediated immunity at 14 and 21 d of age, respectively. Humoral immunity was improved by thyme and savory extracts (P < 0.05. Overall, the effect of in ovo injection of nano-silver, thyme and savory extracts during embryonic development is a potential means to improve immune activities of broiler chickens, while does not have any detrimental effect on embryo hatchability.

  13. Synthesis of Nitrogen-Doped Carbon Nano tubes Using Injection-Vertical Chemical Vapor Deposition: Effects of Synthesis Parameters on the Nitrogen Content

    International Nuclear Information System (INIS)

    Hachimi, A.; Hakeem, A.; Merzougui, B.; Atieh, M. A.; Merzougui, B.; Atieh, M. A.; Laoui, A.; Swain, G.M.; Chang, Q.; Shao, M.

    2015-01-01

    Nitrogen-doped CNTs (N-CNTs) were synthesized using an injection-vertical chemical vapor deposition (IV-CVD) reactor. This type of reactor is quite useful for the continuous mass production of CNTs. In this work, the optimum deposition conditions for maximizing the incorporation of nitrogen were identified. Ferrocene served as the source of the Fe catalyst and was dissolved in acetonitrile, which served as both the hydrocarbon and nitrogen sources. Different concentrations of ferrocene in acetonitrile were introduced into the top of a vertically aligned reactor at a constant flow rate with hydrogen serving as the carrier. The effects of hydrogen flow rate, growth temperature, and catalyst loading (Fe from the ferrocene) on the microstructure, elemental composition, and yield of N-CNTs were investigated. The N-CNTs possessed a bamboo-like microstructure with a nitrogen doping level as high as 14 at.% when using 2.5 to 5 mg/m L of the ferrocene/acetonitrile mixture at 800 degree under a 1000 sccm flow of hydrogen. A production rate of 100 mg/h was achieved under the optimized synthesis conditions.

  14. Synthesis of Nitrogen-Doped Carbon Nanotubes Using Injection-Vertical Chemical Vapor Deposition: Effects of Synthesis Parameters on the Nitrogen Content

    Directory of Open Access Journals (Sweden)

    Abdouelilah Hachimi

    2015-01-01

    Full Text Available Nitrogen-doped CNTs (N-CNTs were synthesized using an injection-vertical chemical vapor deposition (IV-CVD reactor. This type of reactor is quite useful for the continuous mass production of CNTs. In this work, the optimum deposition conditions for maximizing the incorporation of nitrogen were identified. Ferrocene served as the source of the Fe catalyst and was dissolved in acetonitrile, which served as both the hydrocarbon and nitrogen sources. Different concentrations of ferrocene in acetonitrile were introduced into the top of a vertically aligned reactor at a constant flow rate with hydrogen serving as the carrier. The effects of hydrogen flow rate, growth temperature, and catalyst loading (Fe from the ferrocene on the microstructure, elemental composition, and yield of N-CNTs were investigated. The N-CNTs possessed a bamboo-like microstructure with a nitrogen doping level as high as 14 at.% when using 2.5 to 5 mg/mL of the ferrocene/acetonitrile mixture at 800°C under a 1000 sccm flow of hydrogen. A production rate of 100 mg/h was achieved under the optimized synthesis conditions.

  15. Heater Choice, Dampness and Mould Growth in 26 New Zealand Homes: A Study of Propensity for Mould Growth Using Encapsulated Fungal Spores

    Directory of Open Access Journals (Sweden)

    Mikael Boulic

    2015-02-01

    Full Text Available The relationship between the use of unflued gas heaters (UGH, N = 14 and heat pump heaters (HP, N = 12 located in the living rooms, and mould growth on the living room and bedroom walls, of 26 New Zealand (NZ occupied homes was investigated during winter. Two methods were employed to evaluate the potential of mould growth on walls: (i measurement of daily hyphal growth rate using a fungal detector (encapsulated fungal spores; and (ii estimation of fungal contamination based on a four level scale visual inspection. The average wall psychrometric conditions were significantly different between the two heater type groups, in both the living rooms and the bedrooms with the UGH user homes being colder and damper than HP user homes. The UGHs were found to be a significant additional source of moisture in the living rooms which dramatically increased the capacity for fungi to grow on wall surfaces. The average daily hyphal growth rates were 4 and 16 times higher in the living rooms and in the bedrooms of the UGH user homes, respectively. Results from both mould detection methods gave good agreement, showing that the use of a fungal detector was an efficient method to predict the potential of mould growth on the inside of the external walls in NZ homes.

  16. Subcutaneous Injections

    DEFF Research Database (Denmark)

    Thomsen, Maria

    This thesis is about visualization and characterization of the tissue-device interaction during subcutaneous injection. The tissue pressure build-up during subcutaneous injections was measured in humans. The insulin pen FlexTouchr (Novo Nordisk A/S) was used for the measurements and the pressure ...

  17. Hydromorphone Injection

    Science.gov (United States)

    ... anyone else to use your medication. Store hydromorphone injection in a safe place so that no one else can use it accidentally or on purpose. Keep track of how much medication is left so ... with hydromorphone injection may increase the risk that you will develop ...

  18. Ketorolac Injection

    Science.gov (United States)

    ... an older adult, you should know that ketorolac injection is not as safe as other medications that can be used to treat your condition. Your doctor may choose to prescribe a different medication ... to ketorolac injection.Your doctor or pharmacist will give you the ...

  19. Paclitaxel Injection

    Science.gov (United States)

    (pak'' li tax' el)Paclitaxel injection must be given in a hospital or medical facility under the supervision of a doctor who is experienced in giving chemotherapy medications for cancer.Paclitaxel injection may cause a large decrease in the number of white blood cells (a type of blood cell ...

  20. Influence of the mould on the size of A A 8090 alloy in the material melting bulk state

    International Nuclear Information System (INIS)

    Bolfarini, Claudemiro

    1996-01-01

    Wedge like samples were casted into investment moulds of alumina and spodumen. The later were additionally coated with lithium, barium, magnesium and calcium fluorides and chlorides based salts and other special materials. It was used the 2,6% Li-containing alloy AA8090. The grain size was measured as a function of the wedge thickness nd mould material. The results showed a strong dependence of the grain size to the mould materials for the same cast conditions: pouring temperature, mould temperature and chemical composition of the alloy. The AA8090 alloy had no addition of titanium-boron based grain refiner. (author)

  1. The Influence of the Content of Furfuryl Alcohol Monomer on the Process of Moulding Sand's Thermal Destruction

    Directory of Open Access Journals (Sweden)

    Dobosz St. M.

    2014-10-01

    Full Text Available The article discusses the issue of the influence of furfuryl alcohol content in resin binders on properties of moulding sand at elevated temperature. Reducing the share of this component - due to the requirements of the European Union regarding its toxicity - may cause a decrease in temperature of moulding sands’ destruction and, consequently, the thermal deformation of moulds and the creation of many casting defects. The study examined the impact of the furfuryl alcohol content of the thermal destruction processes and on the strength of the moulding sand at an ambient temperature and the tendency to thermal deformation.

  2. The influence of spray-drying parameters on phase behavior, drug distribution, and in vitro release of injectable microspheres for sustained release.

    Science.gov (United States)

    Meeus, Joke; Lenaerts, Maité; Scurr, David J; Amssoms, Katie; Davies, Martyn C; Roberts, Clive J; Van Den Mooter, Guy

    2015-04-01

    For ternary solid dispersions, it is indispensable to characterize their structure, phase behavior, and the spatial distribution of the dispersed drug as this might influence the release profile and/or stability of these formulations. This study shows how formulation (feed concentration) and process (feed rate, inlet air temperature, and atomizing air pressure) parameters can influence the characteristics of ternary spray-dried solid dispersions. The microspheres considered here consist of a poly(lactic-co-glycolic acid) (PLGA) surface layer and an underlying polyvinylpyrrolidone (PVP) phase. A poorly soluble active pharmaceutical ingredient (API) was molecularly dispersed in this matrix. Differences were observed in component miscibility, phase heterogeneity, particle size, morphology, as well as API surface coverage for selected spray-drying parameters. Observed differences are likely because of changes in the droplet generation, evaporation, and thus particle formation processes. However, varying particle characteristics did not influence the drug release of the formulations studied, indicating the robustness of this approach to produce particles of consistent drug release characteristics. This is likely because of the fact that the release is dominated by diffusion from the PVP layer through pores in the PLGA surface layer and that observed differences in the latter have no influence on the release. © 2015 Wiley Periodicals, Inc. and the American Pharmacists Association.

  3. CURING OF POLYMERIC COMPOSITES USING MICROWAVE RESIN TRANSFER MOULDING (RTM

    Directory of Open Access Journals (Sweden)

    R. YUSOFF

    2007-08-01

    Full Text Available The main objective of this work is to compare the difference between microwave heating and conventional thermal heating in fabricating carbon/epoxy composites. Two types of epoxy resin systems were used as matrices, LY5052-HY5052 and DGEBA-HY917-DY073. All composite samples were fabricated using resin transfer moulding (RTM technique. The curing of the LY5052-HY5052-carbon and the DGEBA-HY917-DY073-carbon composite systems, were carried out at 100 °C and 120 °C, respectively. Microwave heating showed better temperature control than conventional heating, however, the heating rate of the microwave cured samples were slower than the conventionally cured samples. This was attributed to the lower power (250 W used when heating with microwaves compared to 2000 W used in conventional heating. Study of thermal characteristics as curing progressed showed that the polymerisation reaction occurred at a faster rate during microwave curing than in conventional curing for both the DGEBA and the LY/HY5052 carbon composite systems. The actual cure cycle was reduced from 60 minutes to 40 minutes when using microwaves for curing DGEBA-carbon composites. As for LY/HY5052-carbon composites, the actual cure cycle was reduced from 3 hours to 40 minutes. Both conventional and microwave heating yielded similar glass transition temperatures (120 °C for DGEBA systems and 130 °C for LY/HY5052 systems. Microwave cured composites had higher void contents than conventionally cured composites (2.2-2.8% and 1.8-2.4% for DGEBA and LY/HY5052 microwave cured composites, respectively, compared to 0.2-0.4% for both DGEBA and LY/HY5052 thermally cured composites. C-scan traces showed that all composites, regardless of methods of curing, had minimal defects.

  4. Microinjection moulding of polymeric composites with functionalized carbon nanotubes =

    Science.gov (United States)

    Ferreira, Tania Sofia Araujo Figueiras

    Microinjection moulding of polymeric composites with functionalized carbon nanotubes The unique electronic, mechanical, and structural properties of carbon nanotubes (CNT) make them suitable for applications in the fields of electronics, sensors, medical devices, aerospace and automotive industries. The preparation of CNT/polymer nanocomposites presents particular interest among the various possible applications. However, the long entangled nanotubes form agglomerates that poses serious obstacles to further development of nanocomposites with the target properties. One of the approaches to overcome the CNT chemical inertness, enhance the compatibility with the matrix and improve homogeneous dispersion through the matrix is through its covalent functionalization. This is expected to improve the CNT interface with the polymer matrix, thus improving the mechanical properties of the nanocomposites at very low content. One of the purposes of this thesis was to implement the covalent modification of the CNT surface using a simple functionalization method, to increase the CNT surface reactivity and possibly help their dispersion into the polyamide matrix without inducing structural damage on the CNT. The functionalization of CNT was carried out through the 1,3-dipolar cycloaddition reaction of azomethine ylides using a solvent-free reaction route. CNT were successful functionalized with pyrrolidine groups through a simple and fast procedure that was scaled up, and may be compatible with current industrial processes. Another objective was to disperse the CNT in polyamide 6 (PA6) using melt mixing, and to produce PA6/CNT nanocomposites by microinjection molding (plM). Finally, the morphological and physical properties of the mouldings produced were evaluated. The plM process is becoming of greater importance for the manufacturing of polymeric micro- components considering its low cost and short cycle times, useful for mass production. The as-received and functionalized CNT

  5. The PEP injection system

    International Nuclear Information System (INIS)

    Brown, K.L.; Avery, R.T.; Peterson, J.M.

    1988-01-01

    A system to transport 10-to-15-GeV electron and positron beams from the Stanford Linear Accelerator and to inject them into the PEP storage ring under a wide variety of lattice configurations has been designed. Optically, the transport line consists of three 360/degree/ phase-shift sections of FODO lattice, with bending magnets interspersed in such a way as to provide achromaticity, convenience in energy and emittance definition, and independent tuning of the various optical parameters for matching into the ring. The last 360/degree/ of phase shift has 88 milliradians of bend in a vertical plane and deposits the beam at the injection septum via a Lambertson magnet. Injection is accomplished by launching the beam with several centimeters of radial betatron amplitude in a fast bump provided by a triad of pulsed kicker magnets. Radiation damping reduces the collective amplitude quickly enough to allow injection at a high repetition rate

  6. Moulding Sands with New InorganicBinders - Ecology Assessment in the Aspect of Work Environment

    Directory of Open Access Journals (Sweden)

    I. Szanda

    2012-09-01

    Full Text Available The development of economy and industry introducing new technologies and materials often means the increased threat of occurrenceof factors harmful to humans and environment. Workers employed in foundries as mould pourers are the group of high professional risk.Foundry moulding sands when poured with liquid metal are a source of the emission of harmful, toxic and carcinogenic (benzene,PAHs compounds.The paper presents the results of studies on the concentration of chemical compounds emitted in the process of casting aluminiumalloy and brass using moulding sands with the new inorganic binders. The specific values of the exposure indices were compared with thelimit values. This enabled an assessment of the impact of moulding sands on work environment. The obtained results were compared withthe values of contaminants emitted when pouring foundry moulds made from furan sands and bentonite sands with an addition of coaldust.Studies were carried out under the project POIG.01.01.02-00-015/09 "Advanced materials and technologies."

  7. Fungi associated with black mould on baobab trees in southern Africa.

    Science.gov (United States)

    Cruywagen, Elsie M; Crous, Pedro W; Roux, Jolanda; Slippers, Bernard; Wingfield, Michael J

    2015-07-01

    There have been numerous reports in the scientific and popular literature suggesting that African baobab (Adansonia digitata) trees are dying, with symptoms including a black mould on their bark. The aim of this study was to determine the identity of the fungi causing this black mould and to consider whether they might be affecting the health of trees. The fungi were identified by sequencing directly from mycelium on the infected tissue as well as from cultures on agar. Sequence data for the ITS region of the rDNA resulted in the identification of four fungi including Aureobasidium pullulans, Toxicocladosporium irritans and a new species of Rachicladosporium described here as Rachicladosporium africanum. A single isolate of an unknown Cladosporium sp. was also found. These fungi, referred to here as black mould, are not true sooty mould fungi and they were shown to penetrate below the bark of infected tissue, causing a distinct host reaction. Although infections can lead to dieback of small twigs on severely infected branches, the mould was not found to kill trees.

  8. Placement suitability criteria of composite tape for mould surface in automated tape placement

    Directory of Open Access Journals (Sweden)

    Zhang Peng

    2015-10-01

    Full Text Available Automated tape placement is an important automated process used for fabrication of large composite structures in aeronautical industry. The carbon fiber composite parts realized with this process tend to replace the aluminum parts produced by high-speed machining. It is difficult to determine the appropriate width of the composite tape in automated tape placement. Wrinkling will appear in the tape if it does not suit for the mould surface. Thus, this paper deals with establishing placement suitability criteria of the composite tape for the mould surface. With the assumptions for ideal mapping and by applying some principles and theorems of differential geometry, the centerline trajectory of the composite tape is identified to follow the geodesic. The placement suitability of the composite tape is examined on three different types of non-developable mould surfaces and four criteria are derived. The developed criteria have been used to test the deposition process over several mould surfaces and the appropriate width for each mould surface is obtained by referring to these criteria.

  9. Temozolomide Injection

    Science.gov (United States)

    ... balance or coordination fainting dizziness hair loss insomnia memory problems pain, itching, swelling, or redness in the place where the medication was injected changes in vision Some side effects can be serious. If you ...

  10. Buprenorphine Injection

    Science.gov (United States)

    ... injection is in a class of medications called opiate partial agonists. It works to prevent withdrawal symptoms ... help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, ...

  11. Risperidone Injection

    Science.gov (United States)

    ... release (long-acting) injection is used to treat schizophrenia (a mental illness that causes disturbed or unusual ... may help control your symptoms but will not cure your condition. Continue to keep appointments to receive ...

  12. Haloperidol Injection

    Science.gov (United States)

    ... haloperidol extended-release injection are used to treat schizophrenia (a mental illness that causes disturbed or unusual ... may help control your symptoms but will not cure your condition. Continue to keep appointments to receive ...

  13. Omalizumab Injection

    Science.gov (United States)

    ... injection is used to decrease the number of asthma attacks (sudden episodes of wheezing, shortness of breath, and ... about how to treat symptoms of a sudden asthma attack. If your asthma symptoms get worse or if ...

  14. Injection Tests

    CERN Document Server

    Kain, V

    2009-01-01

    The success of the start-up of the LHC on 10th of September was in part due to the preparation without beam and injection tests in 2008. The injection tests allowed debugging and improvement in appropriate portions to allow safe, efficient and state-of-the-art commissioning later on. The usefulness of such an approach for a successful start-up becomes obvious when looking at the problems we encountered before and during the injection tests and could solve during this period. The outline of the preparation and highlights of the different injection tests will be presented and the excellent performance of many tools discussed. A list of shortcomings will follow, leading to some planning for the preparation of the run in 2009.

  15. Cefotaxime Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefotaxime injection will not work for colds, flu, or other viral infections. Using ...

  16. Cefuroxime Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefuroxime injection will not work for colds, flu, or other viral infections. Using ...

  17. Doripenem Injection

    Science.gov (United States)

    ... is in a class of medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as doripenem injection will not work for colds, flu, or other viral infections. Taking ...

  18. Daptomycin Injection

    Science.gov (United States)

    ... in a class of medications called cyclic lipopeptide antibiotics. It works by killing bacteria.Antibiotics such as daptomycin injection will not work for treating colds, flu, or other viral infections. ...

  19. Ceftaroline Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftaroline injection will not work for colds, flu, or other viral infections. Using ...

  20. Aztreonam Injection

    Science.gov (United States)

    ... is in a class of medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as aztreonam injection will not work for colds, flu, or other viral infections. Taking ...

  1. Cefazolin Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefazolin injection will not work for colds, flu, or other viral infections. Taking ...

  2. Ceftazidime Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftazidime injection will not work for colds, flu, or other viral infections. Using ...

  3. Cefotetan Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefotetan injection will not work for colds, flu, or other viral infections. Using ...

  4. Cefoxitin Injection

    Science.gov (United States)

    ... is in a class of medications called cephamycin antibiotics. It works by killing bacteria.Antibiotics such as cefoxitin injection will not work for colds, flu, or other viral infections. Taking ...

  5. Tigecycline Injection

    Science.gov (United States)

    ... is in a class of medications called tetracycline antibiotics. It works by killing bacteria that cause infection.Antibiotics such as tigecycline injection will not work for colds, flu, or other viral infections. Using ...

  6. Ertapenem Injection

    Science.gov (United States)

    ... is in a class of medications called carbapenem antibiotics. It works by killing bacteria.Antibiotics such as ertapenem injection will not work for colds, flu, or other viral infections. Taking ...

  7. Ceftriaxone Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as ceftriaxone injection will not work for colds, flu, or other viral infections.Using ...

  8. Cefepime Injection

    Science.gov (United States)

    ... is in a class of medications called cephalosporin antibiotics. It works by killing bacteria.Antibiotics such as cefepime injection will not work for colds, flu, or other viral infections. Using ...

  9. Telavancin Injection

    Science.gov (United States)

    ... is in a class of medications called lipoglycopeptide antibiotics. It works by killing bacteria that cause infection.Antibiotics such as telavancin injection will not work for colds, flu, or other viral infections. Using ...

  10. Doxycycline Injection

    Science.gov (United States)

    ... is in a class of medications called tetracycline antibiotics. It works by killing bacteria that cause infections.Antibiotics such as doxycycline injection will not work for colds, flu, or other viral infections. Taking ...

  11. Vancomycin Injection

    Science.gov (United States)

    ... is in a class of medications called glycopeptide antibiotics. It works by killing bacteria that cause infections.Antibiotics such as vancomycin injection will not work for colds, flu, or other viral infections. Taking ...

  12. Octreotide Injection

    Science.gov (United States)

    ... carton and protect it from light. Dispose of multi-dose vials of the immediate-release injection 14 ... and immediately place the medication in a safe location – one that is up and away and out ...

  13. Moxifloxacin Injection

    Science.gov (United States)

    ... tendon area, or inability to move or to bear weight on an affected area.Using moxifloxacin injection ... muscle weakness) and cause severe difficulty breathing or death. Tell your doctor if you have myasthenia gravis. ...

  14. Delafloxacin Injection

    Science.gov (United States)

    ... a tendon area, or inability to move or bear weight on an affected area.Using delafloxacin injection ... muscle weakness) and cause severe difficulty breathing or death. Tell your doctor if you have myasthenia gravis. ...

  15. Levofloxacin Injection

    Science.gov (United States)

    ... tendon area, or inability to move or to bear weight on an affected area.Using levofloxacin injection ... muscle weakness) and cause severe difficulty breathing or death. Tell your doctor if you have myasthenia gravis. ...

  16. Ciprofloxacin Injection

    Science.gov (United States)

    ... a tendon area, or inability to move or bear weight on an affected area.Using ciprofloxacin injection ... muscle weakness) and cause severe difficulty breathing or death. Tell your doctor if you have myasthenia gravis. ...

  17. Alirocumab Injection

    Science.gov (United States)

    ... 9 (PCSK9) inhibitor monoclonal antibodies. It works by blocking the production of LDL cholesterol in the body ... hives difficulty breathing or swallowing swelling of the face, throat, tongue, lips, and eyes Alirocumab injection may ...

  18. Evolocumab Injection

    Science.gov (United States)

    ... 9 (PCSK9) inhibitor monoclonal antibody. It works by blocking the production of LDL cholesterol in the body ... hives difficulty breathing or swallowing swelling of the face, throat, tongue, lips, and eyes Evolocumab injection may ...

  19. Acyclovir Injection

    Science.gov (United States)

    ... It is also used to treat first-time genital herpes outbreaks (a herpes virus infection that causes sores ... in the body. Acyclovir injection will not cure genital herpes and may not stop the spread of genital ...

  20. Butorphanol Injection

    Science.gov (United States)

    ... Butorphanol is in a class of medications called opioid agonist-antagonists. It works by changing the way ... suddenly stop using butorphanol injection, you may experience withdrawal symptoms such as nervousness, agitation, shakiness, diarrhea, chills, ...

  1. The efficacy of preventive parasternal single injection of bupivacaine on intubation time, blood gas parameters, narcotic requirement, and pain relief after open heart surgery: A randomized clinical trial study

    Directory of Open Access Journals (Sweden)

    Mahmoud Saeidi

    2011-01-01

    Full Text Available Background: Postsurgical pain usually results in some complications in the patients. This study has tried to investigate the effects of parasternal single injection of bupivacaine on postoperative pulmonary and pain consequences in patients after open heart surgery. Methods: : In a prospective double blind clinical study, 100 consenting patients undergoing elective open heart surgery were randomized into two groups. In case group, bupivacaine was injected at both sides of sternum, immediately before sternal closure. In the control group, no intervention was performed. Then, the patients were investigated regarding intubation period, length of ICU stay, arterial blood gas (ABG parameters, morphine requirement, and their severity of postoperative pain using a visual analogue scale (VAS device. Results: No differences were found between the two groups regarding to age, sex, pump time, operation time, and body mass index and preoperative cardiac ejection fraction. Mean intubation length in case group was much shorter than that in control group. Mean PaO 2 in case group was lower in different checking times in postoperative period. The patients in the case group needed less morphine compared to those in the control group during the 24-hour observation period in the ICU. Finally, mean VAS scores of pain in case group were significantly lower than those in control group at 6, 12, and 24 hours postoperatively. Conclusions: Patients′ pain relief by parasternal single injection of bupivacaine in early postoperative period can facilitate earlier ventilator weaning and tracheal extubation after open heart surgery as well as achieving lower pain scores and narcotic requirements.

  2. Investigations of the Quality of the Reclaim of Spent Moulding Sands with Organic Binders

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2012-09-01

    Full Text Available Modern investigation methods and equipment for the quality estimation of the moulding sands matrices with organic binders, in theircirculation process, are presented in the paper. These methods, utilising the special equipment combined with the authors investigationmethods developed in the Faculty of Foundry Engineering, AGH the University of Science and Technology, allow for the better estimationof the matrix quality. Moulding sands systems with organic binders require an in-depth approach to factors deciding on the matrixtechnological suitability as well as on their environmental impact. Into modern methods allowing for the better assessment of the matrixquality belongs the grain size analysis of the reclaimed material performed by means of the laser diffraction and also the estimation of the moulding sand gas evolution rate and identification of the emitted gases and their BTEX group gases content, since they are specially hazardous from the point of view of the Occupational Safety and Health.

  3. Investigations of the Quality of The Reclaim of Spent Moulding Sands with Organic Binders

    Directory of Open Access Journals (Sweden)

    Dańko R.

    2012-09-01

    Full Text Available Modern investigation methods and equipment for the quality estimation of the moulding sands matrices with organic binders, in their circulation process, are presented in the paper. These methods, utilising the special equipment combined with the authors investigation methods developed in the Faculty of Foundry Engineering, AGH the University of Science and Technology, allow for the better estimation of the matrix quality. Moulding sands systems with organic binders require an in-depth approach to factors deciding on the matrix technological suitability as well as on their environmental impact. Into modern methods allowing for the better assessment of the matrix quality belongs the grain size analysis of the reclaimed material performed by means of the laser diffraction and also the estimation of the moulding sand gas evolution rate and identification of the emitted gases and their BTEX group gases content, since they are specially hazardous from the point of view of the Occupational Safety and Health.

  4. Brachytherapy at the Institut Gustave-Roussy: Personalized vaginal mould applicator: technical modification and improvement

    International Nuclear Information System (INIS)

    Albano, M.; Dumas, I.; Haie-Meder, C.

    2008-01-01

    Brachytherapy plays an important role in the treatment of patients with gynaecological cancers. At the Institut Gustave-Roussy, the technique of vaginal mould applicator has been used for decades. This technique allows a personalized tailored irradiation, integrating tumour shape, size and extension and vaginal anatomy. Vaginal expansion reduces the dose to the vaginal mucosa and to the organs at risk. We report a modification of the material used for vaginal mould manufacture. The advantages of the new material are a lighter weight, and transparency allowing a better accuracy in the placement of catheters for radioactive sources. This material is applicable for low dose-rate, pulse dose-rate and high dose-rate brachytherapy. Since 2001, more than 700 vaginal moulds have been manufactured with this new approach without any intolerance. (authors)

  5. [Study on the quantitative and qualitative composition of moulds colonizing sunflower seeds (Helianthus annus L.)].

    Science.gov (United States)

    Janda, Katarzyna; Wolska, Jolanta; Debia, Kamila

    2015-01-01

    The aim of study was to estimate the qualitative and quantitative composition of moulds colonizing sunflower seeds on RBCA, YpSs, DG18 media at 25, 37, and 45°C. Twenty samples of sunflower seeds (not roasted and not salted) were used for the analysis. The highest number of moulds were xerophilic species isolated on DG18 at 25°C (33), followed by mesophilic species (29) on RBCA medium at 25°C, and mesophilic (22) and thermophilic species (10) on YpSs medium at 37, and 45°C, respectively. Eurotium herbariorum was isolated from all samples. A total of 287 strains belonging to 52 mould species were isolated from sunflower seeds. The study revealed new species not previously isolated from sunflower seeds mycobiota.

  6. Manufacturing of kevlar/polyester composite by resin transfer moulding using conventional and microwave heating

    International Nuclear Information System (INIS)

    Abdullah, I.

    2015-01-01

    Microwave heating was incorporated into the resin transfer moulding technique. Polytetrafluoroethylene (PTFE) mould was used to cure the composite panel. Through the use of microwave heating, the mechanical and physical properties of produced Kevlar fibre/polyester composites were compared to those manufactured by conventional resin transfer moulding. The flexural modulus and flexural strength of 6-ply conventionally cured composites was 45% and 9% higher than the flexural modulus and flexural strength of 6-ply microwaved cured composites, respectively. However, 19% increase in interlaminar shear strength (ILSS) and 2% increase in compressive strength was observed in 6-ply microwave cured composites. This enhancement in ILSS and compressive strength is attributed to the better interfacial bonding of polyester resin with Kevlar fibres in microwaved cured composite, which was also confirmed via electron microscopy scanning. Furthermore, the microwave cured composite yielded maximum void contents (3%). (author)

  7. Advanced oxidation and adsorption modification of dust waste from standard moulding sands

    Directory of Open Access Journals (Sweden)

    A. Baliński

    2010-04-01

    Full Text Available The article discusses the process of advanced oxidation (AO with application of ultrasounds and surface modification of the dust waste collected during dry dedusting of processed moulding sands with bentonite binder. A beneficial effect of both AO and adsorption modification of dust waste, when performed with the selected type of polyelectrolyte, on the technological and mechanical properties of moulding sands prepared with an addition of this dust has been stated. In spite of the bentonite content in moulding sand reduced by 43% and replaced with modified dust waste, the mechanical properties, i.e. the compression and tensile strengths, examined on sand specimens have been improved by 10% and 13%, respectively, with no harm to other basic technological sand properties. At the same time, it was also possible to reduce by about 30% the emission rate of the main gaseous component from the BTEX group, i.e. benzene.

  8. A feasibility study for using ABS plastic and a low-cost 3D printer for patient-specific brachytherapy mould design.

    Science.gov (United States)

    Harris, Benjamin D; Nilsson, Sanna; Poole, Christopher M

    2015-09-01

    This feasibility study aims to determine if a low-cost 3D printer (BitsFromBytes 3D Touch) with ABS plastic can print custom mould structures and catheter channels defined in a brachytherapy treatment planning system (Nucletron Oncentra) for patient-specific treatment. Printer accuracy was evaluated through physical measurement, and print quality was investigated by adjusting print parameters (print speed, layer thickness, percentage infill). Catheter positioning and reproducibility were measured over repeated insertions. ABS plastic water equivalency was investigated by comparing Ir-192 HDR source dose distributions, measured with radiochromic film, in ABS plastic and in water. Structures and catheter channels were printed accurately to within 0.5 mm laterally and 1 mm in the vertical print direction. Adjusting print parameters could reduce print time, albeit with reduced print quality. 3.5 mm channel diameters allowed for easy catheter insertion. Catheter positioning was reproducible to within 0.5 mm but, because of catheter flex within the channel, was on average 1 mm offset from defined TPS positions. This offset could be accounted for by repeating the treatment planning CT scan with the printed mould positioned on the patient. Dose attenuation in ABS plastic and in water was equivalent to within the measurement limitations. While clinical uses for this particular low-cost printer and ABS plastic are limited by print size restrictions and non-certification for biocompatibility, it has been demonstrated that a low-cost 3D printer set-up can accurately create custom moulds and catheter channels potentially acceptable for clinical use.

  9. Physical metallurgy of laser surface melted plastic mould steels: a case study

    Directory of Open Access Journals (Sweden)

    Colaço, R.

    1998-04-01

    Full Text Available The purpose of this paper is to illustrate the potential of laser surface melting to improve the surface characteristics of plastic mould steels, using a typical plastic mould steel (DIN X43Cr12 as a case study. After laser surface melting the microstructure of this steel is formed by fine dendrites of austenite partially transformed into martensite. Although the equilibrium solidification phase is 8- ferrite, the formation of primary austenite is kinetically favored and this phase tends to predominate at the high solidification speeds used in laser processing. It was observed that the volume fraction of retained austenite depends critically on the laser processing parameters, so that the microstructure can change from almost completely martensitic to almost completely austenitic by changing the laser processing parameters. Laser melted tool steels show remarkable secondary hardening after tempering at suitable temperatures. In DIN X42Cr13 the secondary hardening peak temperature after LSM (600°C is 100°C higher than after conventional heat treatment (500°C, due to the presence of large amounts of retained austenite. It was observed that this phase only destabilizes above 600°C, due to the precipitation of M7C3 and stress relieving. After destabilization, retained austenite transforms into martensite during cooling. Secondary hardening is due to the transformation of retained austenite into martensite and to the precipitation of M7C3 and M23C6 carbides.

    El objetivo del presente trabajo es ilustrar el potencial de la fusión superficial mediante láser para la mejora de las características estructurales de los moldes de acero para plásticos, centrándolo en el caso concreto del acero DIN X42Cr13. Tras el tratamiento de fusión superficial mediante láser, la microestructura del material está formada por dendritas finas de austenita parcialmente transformadas en

  10. Optimizing {sup 18}F-FDG PET/CT imaging of vessel wall inflammation: the impact of {sup 18}F-FDG circulation time, injected dose, uptake parameters, and fasting blood glucose levels

    Energy Technology Data Exchange (ETDEWEB)

    Bucerius, Jan [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Maastricht University Medical Center, Department of Nuclear Medicine, Maastricht (Netherlands); Maastricht University Medical Center, Cardiovascular Research Institute Maastricht (CARIM), Maastricht (Netherlands); University Hospital, RWTH Aachen, Department of Nuclear Medicine, Aachen (Germany); Mani, Venkatesh; Fayad, Zahi A. [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Moncrieff, Colin [Icahn School of Medicine at Mount Sinai, Translational and Molecular Imaging Institute, One Gustave L. Levy Place, P.O. Box 1234, New York, NY (United States); Mount Sinai School of Medicine, Department of Radiology, New York, NY (United States); Machac, Josef [Mount Sinai School of Medicine, Division of Nuclear Medicine, Department of Radiology, New York, NY (United States); Fuster, Valentin [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); The Centro Nacional de Investigaciones Cardiovasculares (CNIC), Madrid (Spain); Farkouh, Michael E. [Mount Sinai School of Medicine, Department of Cardiology, Zena and Michael A. Weiner Cardiovascular Institute and Marie-Josee and Henry R. Kravis Cardiovascular Health Center, New York, NY (United States); Mount Sinai School of Medicine, Cardiovascular Imaging Clinical Trials Unit, New York, NY (United States); Tawakol, Ahmed [Massachusetts General Hospital, Harvard University, Cardiac MR PET CT Program, Boston, MA (United States); Rudd, James H.F. [Cambridge University, Division of Cardiovascular Medicine, Cambridge (United Kingdom)

    2014-02-15

    {sup 18}F-FDG PET is increasingly used for imaging of vessel wall inflammation. However, limited data are available on the impact of methodological variables, i.e. prescan fasting glucose, FDG circulation time and injected FDG dose, and of different FDG uptake parameters, in vascular FDG PET imaging. Included in the study were 195 patients who underwent vascular FDG PET/CT of the aorta and the carotids. Arterial standardized uptake values ({sub mean}SUV{sub max}), target-to-background ratios ({sub mean}TBR{sub max}) and FDG blood-pool activity in the superior vena cava (SVC) and the jugular veins (JV) were quantified. Vascular FDG uptake values classified according to the tertiles of prescan fasting glucose levels, the FDG circulation time, and the injected FDG dose were compared using ANOVA. Multivariate regression analyses were performed to identify the potential impact of all variables described on the arterial and blood-pool FDG uptake. Tertile analyses revealed FDG circulation times of about 2.5 h and prescan glucose levels of less than 7.0 mmol/l, showing a favorable relationship between arterial and blood-pool FDG uptake. FDG circulation times showed negative associations with aortic{sub mean}SUV{sub max} values as well as SVC and JV FDG blood-pool activity, but positive correlations with aortic and carotid{sub mean}TBR{sub max} values. Prescan glucose levels were negatively associated with aortic and carotid{sub mean}TBR{sub max} and carotid{sub mean}SUV{sub max} values, but were positively correlated with SVC blood-pool uptake. The injected FDG dose failed to show any significant association with vascular FDG uptake. FDG circulation times and prescan blood glucose levels significantly affect FDG uptake in the aortic and carotid walls and may bias the results of image interpretation in patients undergoing vascular FDG PET/CT. The injected FDG dose was less critical. Therefore, circulation times of about 2.5 h and prescan glucose levels less than 7.0 mmol

  11. Application of HS-SPME-GC-MS method for the detection of active moulds on historical parchment.

    Science.gov (United States)

    Sawoszczuk, Tomasz; Syguła-Cholewińska, Justyna; Del Hoyo-Meléndez, Julio M

    2017-03-01

    The goal of this work was to analyse the profile of microbial volatile organic compounds (MVOCs) emitted by moulds growing on parchment samples, in search of particular volatiles mentioned in the literature as indicators of active mould growth. First, the growth of various moulds on samples of parchment was assessed. Those species that showed collagenolytic activity were then inoculated on two types of media: samples of parchment placed on media and on media containing amino acids that are elements of the structure of collagen. All samples were prepared inside 20-ml vials (closed system). In the first case, the media did not contain any sources of organic carbon, nitrogen, or sulphur, i.e. parchment was the only nutrient for the moulds. A third type of sample was historical parchment prepared in a Petri dish without a medium and inoculated with a collagenolytically active mould (open system). The MVOCs emitted by moulds were sampled with the headspace-SPME method. Volatiles extracted on DVB/CAR/PDMS fibres were analysed in a gas chromatography-mass spectrometry system. Qualitative and quantitative analyses of chromatograms were carried out in search of indicators of metabolic activity. The results showed that there are three groups of volatiles that can be used for the detection of active forms of moulds on parchment objects. To the best of our knowledge, this is the first work to measure MVOCs emitted by moulds growing on parchment.

  12. Respiratory health in children, and indoor exposure to (1,3)-beta-D-glucan, EPS mould components and endotoxin

    NARCIS (Netherlands)

    Tischer, C.; Gehring, U.; Chen, C-M; Kerkhof, M.; Koppelman, G.; Sausenthaler, S.; Herbarth, O.; Schaaf, B.; Lehmann, I.; Kraemer, U.; Berdel, D.; von Berg, A.; Bauer, C. P.; Koletzko, S.; Wichmann, H-E; Brunekreef, B.; Heinrich, J.

    For a long time, exposure to mould and dampness-derived microbial components was considered a risk factor for the development of respiratory diseases and symptoms. Some recent studies suggested that early childhood exposure to mould components, such as (1,3)-beta-D-glucan and extracellular

  13. 78 FR 12357 - Brockway Mould, Inc., a Division of Ross International Ltd. Including Robert Lerch From BJR...

    Science.gov (United States)

    2013-02-22

    ... Division of Ross International Ltd. Including Robert Lerch From BJR Trucking, Brockport, PA; Amended..., applicable to workers and former workers of Brockway Mould, Inc., a division of Ross International Ltd... Brockway Mould, Inc., a division of Ross International Ltd., including Robert Lerch from BJR Trucking...

  14. Facial asymmetry correction with moulded helmet therapy in infants with deformational skull base plagiocephaly.

    Science.gov (United States)

    Kreutz, Matthias; Fitze, Brigitte; Blecher, Christoph; Marcello, Augello; Simon, Ruben; Cremer, Rebecca; Zeilhofer, Hans-Florian; Kunz, Christoph; Mayr, Johannes

    2018-01-01

    The recommendation issued by the American Academy of Pediatrics in the early 1990s to position infants on their back during sleep to prevent sudden infant death syndrome (SIDS) has dramatically reduced the number of deaths due to SIDS but has also markedly increased the prevalence of positional skull deformation in infants. Deformation of the base of the skull occurs predominantly in very severe deformational plagiocephaly and is accompanied by facial asymmetry, as well as an altered ear position, called ear shift. Moulded helmet therapy has become an accepted treatment strategy for infants with deformational plagiocephaly. The aim of this study was to determine whether facial asymmetry could be corrected by moulded helmet therapy. In this retrospective, single-centre study, we analysed facial asymmetry of 71 infants with severe deformational plagiocephaly with or without deformational brachycephaly who were undergoing moulded helmet therapy between 2009 and 2013. Computer-assisted, three-dimensional, soft-tissue photographic scanning was used to record the head shape before and after moulded helmet therapy. The distance between two landmarks in the midline of the face (i.e., root of the nose and nasal septum) and the right and left tragus were measured on computer-generated indirect and objective 3D photogrammetry images. A quotient was calculated between the two right- and left-sided distances to the midline. Quotients were compared before and after moulded helmet therapy. Infants without any therapy served as a control group. The median age of the infants before onset of moulded helmet therapy was 5 months (range 3-16 months). The median duration of moulded helmet therapy was 5 months (range 1-16 months). Comparison of the pre- and post-treatment quotients of the left vs. right distances measured between the tragus and root of the nose (n = 71) and nasal septum (n = 71) revealed a significant reduction of the asymmetry (Tragus-Nasion-Line Quotient: 0

  15. Reclamation of alkaline spent moulding sands of organic and inorganic type and their mixtures

    Directory of Open Access Journals (Sweden)

    R. Dańko

    2011-10-01

    Full Text Available Introduction of modern moulding sands with organic and inorganic binders requires the reclamation treatments in order to be able to reuse the matrices of spent sands. The spent sands, depending on the applied binding agent, are characterised by various abilities of the matrix reclamation. The results of investigations of the reclamation of spent moulding sands with the Rudal binder and spent sands with the Rezolit binder in the system of uniform sands and of mixed ones, are presented in the paper. Investigations were performed by means of the special experimental stands designed and built in the AGH University of Science and Technology, AGH, in Krakow.

  16. Effect of gamma radiation on storage moulds of wheat and maize

    International Nuclear Information System (INIS)

    Lal, S.P.; Kapoor, J.N.; Chatrath, M.S.

    1977-01-01

    The effect of different dosages of gamma radiation on the development of moulds on grains of wheat and maize and on the germination of the spores of these fungi was studied. There was marked reduction in storage moulds with increase in the dose and at a dose of 300 Krad, their development on grains was completely inhibited. The results on germination of spores of these fungi when treated with various radiation dosages show that several species of Aspergillus and Penicillium differed remarkably in their sensitivity to radiation. (author)

  17. Iron Melt Flow in Thin Walled Sections Cast in Vertically Parted Green Sand Moulds

    DEFF Research Database (Denmark)

    Larsen, Per; Andersen, Uffa; Rasmussen, Niels

    Shortage of resources can be expected to become more wide spread in the future. Furthermore the focus on the environmental aspects will also be intensified. Today the clearest example is the large attention on the fuel consumption of cars. Many different approaches can be made to reduce the fuel ...... of gating systems investigated in this work, cannot be recommended for castings with high demands to the quality, as the variation in the filling patterns can be very large from mould to mould and hence the stability of the quality will be affected....

  18. Influence of the Mould Cooling Process on the Quality and Properties of Aluminium Alloy

    Directory of Open Access Journals (Sweden)

    Viktorie Weiss

    2014-12-01

    Full Text Available The article deals with the effect on the quality of casting moulds (metal, bentonite mixture on the structure of the alloy AlZn5,5MgCu and selected mechanical properties of the alloy. The effect of foundry moulds can significantly affect formation and range of crystal segregation and the subsequent thermal process of homogenization which has an influence on the final quality of the alloy. The research focuses on the formation and range of crystal segregation and its removal with homogenization annealing, in which the observed influence of individual factors influencing the diffusion process and quality of the aluminium alloy.

  19. Determination of Unit Pressure Force in Material Volume in the Course of Refractory Stamping Press Moulding

    Directory of Open Access Journals (Sweden)

    Orłowicz A.W.

    2016-06-01

    Full Text Available The paper presents results of assessment of the unit pressure force within the refractory material volume in the course press-moulding of stampings for refractory precast shapes. The force was evaluated with the use of physical simulation of deformation undergone by lead balls placed in the raw refractory mass subjected to pressing in a metal die. To determine the value of unit pressure force applied to the aggregate grains in the course of stamping press-moulding, physical model of deformation of a sphere induced by the uniaxial stress state was used.

  20. Investigating the effects of laser beams (532 and 660 nm) in annihilation of pistachio mould fungus using spectrophotometry analysis

    Science.gov (United States)

    Saghafi, S.; Penjweini, R.; Becker, K.; Kratky, K. W.; Dodt, H.-U.

    2010-09-01

    When moulds are illuminated by visible electromagnetic-EM radiations, several effects on nucleus materials and nucleotides can be detected. These effects have a significant influence on mould generation or destruction. This paper presents the effects and implications of a red diode laser beam (660 nm), a second-harmonics of a Nd:YAG laser emitting green beam (532 nm), or the combination of both, on the eradication of Pistachio mould fungus. Incident doses (ID) of both beams are kept identical throughout the experiment. The absorption spectrums of irradiated mouldy samples and the bright-greenish-yellow-fluorescence (BGYF) of fungus occurring in mould texture due to electronic excitation are investigated. We found that a combination of a green and a red laser beam with an ID of 0.5 J/cm2 provides the optimal effects on Pistachio mould fungus eradication.