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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
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Journal of The Korean Society of Manufacturing Technology Engineers
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Journal DOI :
The Korean Society of Manufacturing Technology Engineers
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Volume & Issues
Volume 20, Issue 6 - Dec 2011
Volume 20, Issue 5 - Oct 2011
Volume 20, Issue 4 - Aug 2011
Volume 20, Issue 3 - Jun 2011
Volume 20, Issue 2 - Apr 2011
Volume 20, Issue 1 - Feb 2011
Selecting the target year
Design of a Condenser Lens System using a Thin Lens Combination
Lim, Sun-Jong ; Choi, Ji-Yeon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 517~522
Most of SEM is double condenser lens system. Two condenser lenses are required to provide the high demagnification ratios necessary for forming nanometer probes. The thin lens concept provides a highly useful basis for preliminary calculations in a broad range of situations. It is an easy way to understand the electron beam paths in column. Demagnification is easily calculated by this method. In this paper, we present design processes for condenser lens's demagnification by using thin lens combination model. Also, we verify the reliability of our design processes by comparing the modeled demagnification with these of corrected condenser lens.
Minimization of Pattern Size on Polycarbonate Material in V-grooving
Kim, Gi-Dae ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 523~527
Polycarbonate (PC) polymer is an engineering plastic which has large tensile strength and impact resistance and is wildly used as functional parts like micro mold. Direct machining of PC materials produces lots of burrs and rough surface due to large ductility and weak heat resistance and hence it is very difficult to machine PC materials using cutting tool to make micro-parts. In this study, elliptical vibration cutting (EVC) or 2-dimensional vibration cutting was performed to minimize the size of micro V-grooves on PC material. From the experimental results, it was observed that as the cutting depth and pattern size become smaller, the better machining quality was obtained, which is attributed to the positive effect of EVC that is dependent on the ratio of vibration amplitude to cutting depth. As the height of V-groove becomes less than
, however, the machining quality becomes lower as the pattern size decreases.
Study on Structural Safety Analysis of EGR Valve
Han, Moon-Sik ; Cho, Jae-Ung ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 528~534
This study analyzes thermal stress and durability fatigue on the modelling of EGR valve. In case of 10% opening at its inlet, the minimum temperature gets cool as 3 times as inlet temperature. The maximum equivalent stress becomes lowest as the value of
Pa and fatigue life becomes highest as 23.657 Cycle. But the minimum temperature gets cool as 2.2 times as inlet temperature in case of 50% opening at its inlet. The equivalent stress becomes higher and fatigue life becomes lower than in case of 10% opening. In case of 100% opening at its inlet, the minimum temperature gets cool as 0.2 times as inlet temperature. The equivalent stress becomes lower and fatigue life becomes higher than in case of 50% opening. Maximum equivalent stress and total deformation are shown at the closing of EGR valve by the pressure of inflow gas. The structural analysis result of this study can be effectively utilized with the design of EGR valve by investigating prevention and durability against its damage.
Effects of Mixing Chamber Shape on Cutting Performance in AWJ
Lee, Hyo-Ryeol ; Kwak, Yong-Kil ; Kim, Hwa-Young ; Ahn, Jung-Hwan ; Yeo, Myeong-Heon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 535~540
It is well known that abrasive waterjet (AWJ) was developed as a kind of high-density energy processing technologies. AWJ is used to obtain cutting quality of various materials such as metal, ceramics, glass and composite materials within a short manufacturing time because of the characteristics of heatless and noncontact processing. However, surface roughness and dimension error like round, burr, taper vary severely according to the processing conditions such as pressure, cutting speed, orifice diameter, stand off distance and abrasive flow rate. In this paper, the effect of the shape of mixing chamber on surface quality is studied. Three types of mixing chamber - round, parabolic, elliptical - are suggested and each performance is compared to that of cylindrical mixing chamber experimentally. From the result, is proved to be the optimal mixing chamber in the aspect of surface quality the parabolic one.
Numerical Study on Thermal Deformation of AC4C and AC7A Casting Material
Yoon, Hee-Sung ; Oh, Yool-Kwon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 541~546
This study was numerically investigated on thermal deformation of AC4C and AC7A aluminum alloy casting material for manufacturing the automobile tire mold. The metal casting device was used in order to manufacture the mold product of automobile tire at the actual industrial field. The temperature distribution and the cooling time of these materials were numerically calculated by finite element analysis. Thermal deformation with stress distribution was also calculated form the temperature distribution results. The thermal deformation was closely related to the temperature difference between the surface and inside of the casting. As shown by numerical analysis result, the thermal deformation of AC7A casting material became higher than AC4C casting material. In addition, the results of displacement and stress distributions appeared to be larger at the center parts of casting than on its sides because of the shrinkage caused by the cooling speed difference.
Optimal Flow Design of High-Efficiency, Cold-Flow, and Large-size Heat Pump Dryer
Park, Sang-Jun ; Lee, Young-Lim ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 547~552
Drying process, corresponding to a final process in the area of food engineering, requires a lot of heat energy. Thus, the energy efficiency is very important for dryers. Since the energy efficiency of heat pump dryers is much higher compared to that of electric dryers or other types of dryers, most of large-capacity dryers are adopting heat pump. In this study, shapes, positions and number of air-circulating fans, guide vanes, air inlet, outlet and top separator were varied for optimization of the flow of a large-capacity heat pump dryer. In addition, fans were modelled with performance curves and porous media were assumed for foods and heat exchangers. The simulation results were applied to the 12-ton dryer and the velocity distributions were experimentally examined. Finally, uniform drying in time was successfully accomplished through frozen pepper experiment.
Safety Estimation of High Pressure Drop Control Valve for Offshore Structures
Kim, Jae-Woong ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 553~558
This study have goal with conceptual design for offshore structures of high pressure drop control valve for localization valve for development accomplished with flow analysis based on provision of ANSI B16.34, ANSI B16.10, ANSI B16.25. In order to localize the Offshore structures high pressure drop control valve. This study is numerical analysis for zambil offshore project of high pressure drop control valve. The solver which ANSYS workbench used for offshore structures analysis. The working fluids assumed the glycerin(C3H8O3). The structural analysis used ANSYS which is a commercial code. Stress analysis result of internal pressure in valve showed lower than yield strength. This is expect to need more detail design and verification for stem and disk structure. In this study a multi-disk of high pressure drop control valve is designed and manufactured. Then, the flow rate and high pressure dorp of fluids flowing in the high pressure drop control valve is CAE. So, this system can be easily substituted for the existing zambil offshore project system. Finally, safety estimation for trim design of high pressure drop control valve for offshore structures.
Dynamic Reliability of Board Level by Changing the Design Parameters of Flip Chips
Kim, Seong-Keol ; Lim, Eun-Mo ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 559~563
Drop impact reliability assessment of solder joints on the flip chip is one of the critical issues for micro system packaging. Our previous researches have been showing that new solder ball compositions of Sn-3.0Ag-0.5Cu has better mechanical reliability than Sn-1.0Ag-0.5Cu. In this paper, dynamic reliability analysis using Finite Element Analysis (FEA) is carried out to assess the factors affecting flip chip in drop simulation. The design parameters are size and thickness of chip, and size, pitch and array of solder ball with composition of Sn1.0Ag0.5Cu. The board systems by JEDEC standard including 15 chips, solder balls and PCB are modeled with various design parameter combinations, and through these simulations, maximum yield stress and strain at each chip are shown at the solder balls. It is found that larger chip size, smaller chip array, smaller ball diameter, larger pitch, and larger chip thickness have bad effect on maximum yield stress and strain at solder ball of each chip.
A Study of Welding Conditions for Plastic Piping
Lee, C.K. ; Lee, W.R. ; Park, C.Y. ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 564~569
The current establishment of city gas piping polyethylene (PE) tube used as bonding state or part of the health or safety of fusion is very important. A part of these fusion methods to determine the soundness of the short-term trials and long-term tests can be largely classified. Typical tests include short-term strength, tensile strength, impact strength, compressive strength, resiliency and compression. Polyethylene (PE) pipes installed in the domestic terms of overall penetration rate of 45% has been used. However, polyethylene (PE) pipes have reliability problems, and these occurs mostly in part by defective welding. Therefore, the test is necessary for safety. Non-destructive methods (ultrasonic testing) are difficult to be used. Therefore, Polypropylene copolymer (PP-C), polypropylene homopolymer (PP-H), and polyethylene (PE) pipe are used. Fusion of these materials is necessary in these field however, its technical, and basic research has not been studied well. In this research, short-term strength of welding parts, its tensile strength, hardness, fatigue, and microstructure have been analyzed to find the optimum process conditions to improve mechanical properties.
The Establishment of Bonding Conditions of Cu Using an Ultrasonic Metal Welder
Jang, Ho-Su ; Park, Woo-Yeol ; Park, Dong-Sam ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 570~575
Ultrasonic metal welder is consisted of power supply, transducer, booster, and horn. Precise designing is required since each parts' shape, length and mass can affect driving frequency and vibration mode. This paper analyzed Cu sheet deposition characteristics using ultrasonic metal welder and tension tester. A horn suitable for 40,000Hz was attached to the ultrasonic metal welder in order to weld Cu plates. The Cu sheet welding was done with different amplitude, pressure, and welding time, and its maximum tension was measured with tension tester. Maximum tension of 153.87N was obtained when the pressure was 2.0bar, amplitude was 80%, and welding time was 0.30s. Therefore, excessive welding condition negatively influences maximum tension measurement result.
Deformation Analysis for Dust Cap of Automotive Wheel Bearing
Lee, Seung-Pyo ; Lee, In-Ha ; Kim, Bong-Chul ; Jin, Sung-Kyu ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 576~581
In this paper, deformation of dust cap in the automotive wheel bearing produced during press-fit process was numerically analyzed. The commercial software, MSC.MARC which is based on the finite element method was used to calculate the deformation. From those results, interference between dust cap and sensor was investigated. To verify the analysis results, experiments were performed and compared experiment results with analysis results. To avoid the interference between dust cap and sensor, 4 modified designs were proposed and the best design was derived from them.
Finite Element Analysis on the Cold Forging Process of the Unified Universal Shaft Joint for the Automobile
Kwon, Hyuk-Hong ; Song, Seung-Eun ; Kim, Oh-Seung ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 582~588
This study was aimed at the design of the dies for the unified shaft joint using the computer simulation to shorten the period of production, on the basis of the process planning which was designed by the field experts. In the computer simulation, 'Deform-3d' and 'Eesy-DieOpt' have been used, which are the commercial process analysis and die design program. Through the process analysis, we could know the propriety of the forming process, the inner pressure of the die and the suitable fitting pressure between the insert and the sleeve which was not showing any positive tangential stresses in the insert. Through the simulation of die design, we could know the number of the stress ring, the diameter ratios, the stresses of the die, the shrink fitting tolerance and temperature in the condition of the already determined maximum outer die diameter of the multi-stage former. The validity of the die design using the computer simulation was analyzed by the experiments and the results were satisfactory. As the results of this study, the new and easy die design system for multi-forging has been developed.
Optimal Tuning of a Ballscrew Driven Biaxial Servo System
Shin, Dong-Soo ; Chung, Sung-Chong ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 589~597
In this paper, optimal tuning of a cross-coupled controller linked with the feedforward controller and the disturbance observer is studied to improve contouring and tracking accuracy as well as robustness against disturbance. Previously developed integrated design and optimal tuning methods are applied for developing the robust tuning method. Strict mathematical modeling of the multivariable system is formulated as a state-space equation. Identification processes of the servomechanism are conducted for mechanical servo models. An optimal tuning problem to minimize both the contour error and settling time is formulated as a nonlinear constrained optimization problem including the relevant controller parameters of the servo control system. Constraints such as relative stability, robust stability and overshoot, etc. are considered for the optimization. To verify the effectiveness of the proposed optimal tuning procedure, linear and circular motion experiments are performed on the xy-table. Experimental results confirm the control performance and robustness despite the variation of parameters of the mechanical subsystems.
A Study on The Crash Analysis of Guard Rail
Min, Han-Ki ; Jung, Jong-An ; Kim, Taeg ; Gook, Jin-Seon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 598~604
In guard rail crashes, the development of guard rail structure to ensure the maintenance of safety for passengers is very important. So, this paper focuses on understanding the possibility of efficient structural development considering crash strength of guard rail through computer simulation using the commercial code, LS-DYNA3D at the initial stage of guard rail development. For this study, guard rail structure was modeled using shell elements to represent major structural members and passenger car was modeled using plate elements of simple shape to do not have the drawing, and impact boundary conditions required by regulation was applied. In order to confirm the validity of the computational results, they were compared with the test results.
Thrust Enhancement through a Tandem Mode of Flapping Wing in Micro Flow
Jang, Sung-Min ; Maeng, Joo-Sung ; An, Sang-Joon ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 605~611
In this study, based on previous studies, the thrust generated by using flapping tandem wings is examined. We studied on the relationship between the parameters for characterizing oscillatory tandem wings (namely, the Strouhal number and Reynolds number) for thrust generation in micro flow regime. At each Reynolds number, Strouhal number, heaving amplitude, distance between tandem wings, and phase difference are varied and the flapping motions of tandem mode are calculated to find the optimum conditions for generating thrust. As a result, comparing with a single flapping mode, we found that the minimum Strouhal number for generating thrust is shifted down up to approximately 25% when the tandem flapping mode is applied.
An Experimental Study on Noise Characteristics of Fuel Pump System
Sa, Jong-Sung ; Kang, Tea-Won ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 612~617
The comfort and quietness of vehicle has been improved greatly due to the development of technology in automobile industry. Some of noise reductions, for example, are driven by the improvement in the power-train system. Due to better in all performance, it is required to reduce more noise in automobile components. One of them is related to the fuel pump system including a pump and a tank. Therefore, this study is focused on investigating the characteristics of fuel pump and fuel tank first, and then comparing the data before and after installation of fuel pump system in a testing vehicle. Additionally, the measured data will be analyzed to identify the problems and provide knowledge to reduce the level of noise and vibration in fuel pump system.
Dislocation Density Propagation adjacent to the Low Angle Grain Boundaries of Polycrystalline Materials
Ma, Jeong-Beom ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 618~622
Specialized large-scale computational finite-element and molecular dynamic models have been used in order to understand and predict how dislocation density emission and contact stress field due to nanoindentation affect inelastic deformation evolution scales that span the molecular to the continuum level in ductile crystalline systems. Dislocation density distributions and local stress fields have been obtained for different crystalline slip-system and grain-boundary orientations. The interrelated effects of grain-boundary interfaces and orientations, dislocation density evolution and crystalline structure on indentation inelastic regions have been investigated.
Development and Mass Production Potential of a Novel 5-side Photodiode LED Viewing Angle Measurement System
Kim, Dee-Wan ; Park, Chan-Hee ; Kim, Keun-Sik ; Kim, Cheol-Sang ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 623~631
Light emitting diodes (LEDs) which can produce uniform luminescence need a very difficult and complex procedure because LEDs have strong and straight optical property. One of the major parameters for LED production is the determination of the viewing angle. However, in the present, there is still no available production technology to measure LED viewing angle and optical property. In this study, we developed a five-side LED viewing angle and optical property measurement system, having a source meter that uses a high speed switching photo relay instead of a mercury relay. This new measurement system can measure the viewing angle at a very high accuracy of
. This new technology presents a great potential for fast and reliable LED mass production, which can significantly cut down the cost from savings in production time.
A Study on the Characteristics of Material removal using a Round endmill Type MR Polishing System for 3D Shape
Hong, Kwang-Pyo ; Shin, Bong-Cheol ; Kim, Dong-Woo ; Cho, Myeong-Woo ; Je, TAe-Jin ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 632~638
Recently, it has been studying for the polishing process of micro parts widely. However, present MR polishing system, it is difficult to minimize electromagnet and to polish sphere or slope parts. Then, it can not be obtained demanded surface quality. In this study, material removal characteristics of BK7 glass using round endmill type MR polishing system were investigated through series of experiment. The experiments were investigated by changing imposed polishing conditions, such as rotational speed and polishing depth. As a results, very high material removal was obtained at 0.7mm gap distance, 1,980rpm.
Characteristics Analysis of Automatic Transmission for the Wheel-Loader with Shift Control Algorithm
Oh, Joo-Young ; Yun, Ung-Kwon ; Park, Young-Jun ; Lee, Geun-Ho ; Song, Chang-Seop ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 639~645
Wheel-loader is a construction vehicle for uploading soil or sand into truck and transportation of materials, which requires large driving power and high rotational speed. To improve the working efficiency, the operator has to shift gears and control levers for bucket & boom simultaneously. Therefore, the automatic transmission has been introduced to enhance operator's convenience and enable effective operation. To develop the automatic transmission for the wheel-loader, technologies such as gears and a clutch-pack design and shift algorithm are required for improvement of shift quality. In this paper, the shift algorithm for the wheel-loader was developed and its shift pattern was analyzed. As the shift control is affected by the pressure profile for the clutch control, the shift quality depending on the pressure profile has been evaluated using experiment and simulation model analysis.
A Study on Laser Surface Treatment Characteristics of High Carbon Steel(HP4MA) for Injection Mold
Hwang, Hyun-Tae ; Choi, Hung-Won ; Kim, Jong-Do ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 646~652
Recently, lots of automobile part manufacturers try to increase glass fiber content of their plastic parts to improve strength and impact-resistance. For this reason, injection mold requires high hardness and wear-resistant. Laser surface treatment is used to improve characteristics of wear and to enhance the fatigue resistance for injection mold. In this paper, high carbon steel (HP4MA) for injection mold material was heat-treated to harden surface by using high power diode laser (HPDL). To find the process parameters for laser surface treatment of HP4MA, many experiments are carried out as changing the parameters of surface temperature and travel speed of laser. From the results of the experiments, it has been shown that the maximum average hardness is approximately 711~739 Hv when the temperature and the travel of laser are
and 2 mm/sec.
Development of Automatic Packing System of One Station for Fasteners(II) : Packing System Manufacture and Performance Test
Kim, Yong-Seok ; Jeong, Chan-Se ; Yang, Soon-Young ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 653~658
In general, the purpose of packaging fasteners is a series of management activities to maintain the condition at the time of production until they get delivered to the end user. An automatic packing system for fasteners is consisted of bucket conveyor, slide feeder, vision inspection system, box-magazine conveyor system and automatic packing machine. Also, the automatic packing machine is consisted of six modules including charging device, clamping/opening device, sealing/cutting device, feeding/air-shower device, supplying/adjusting device and device frame, etc. In this paper, we proposed an automatic packing mechanism of the one station concept for packing work of fastener objects where the continuous batch work is performed in a finite space. The proposed one-station packing mechanism has been optimized through mechanical, dynamical, structural and fluid analyses. And it had been manufactured as the prototype of automatic packing machine. The field test for validation of performance was performed directly at the production line of bolt and screw. In the field test, this packing machine showed an efficiency of about 4.5 times the manual operation. It also showed 30% reduction in the consumption of packing materials compared to the manual operation. This automatic packing machine for fastener objects will be commercialized soon.
A Study on the Improvement of Double Injection-molding Keypad Process
Hong, Min-Sung ; Lee, Ji-Hoon ; Shin, Soo-Hyun ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 659~665
Recently, the plastic resin such as PC, ABS are widely used in IT market. Especially, in most cases the keypads mounted on the mobile phone are the dual-injection-plated type. Environmental regulation is based on the quality of injection-molded products and the minimum process steps are required to avoid the plating defects. Various parameters to produce the injection-molded plastic products make it difficult to obtain the desired stability. However, the past experience and the use of CAE analysis make it possible to predict the problems occurred in injection molding process. Especially, the problems of the weld lines such as runner balancing, bending, deformation and forming defects can be solved systematically and minimized by CAE analysis. Through this study, the non-uniform volumetric shrinkage and the difference in temperature distribution induce the deformation and the high value of stress causes the problems such as crack.
Development of Automatic Precision Inspection System for Defect Detection of Photovoltaic Wafer
Baik, Seung-Yeb ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 666~672
In this paper, we describes the development of automatic inspection system for detecting the defects on photovoltaic wafer by using machine vision. Until now, The defect inspection process was manually performed by operators. So these processes caused the produce of poorly-made articles and inaccuracy results. To improve the inspection accuracy, the inspection system is not only configured, but the image processing algorithm is also developed. The inspection system includes dimensional verification and pattern matching which compares a 2-D image of an object to a pattern image the method proves to be computationally efficient and accurate for real time application and we confirmed the applicability of the proposed method though the experience in a complex environment.
A Diesel Power Sharing Algorithm for Wind-Diesel Hybrid Electric Power Generation Systems
Nam, Yong-Youn ; Lee, Geun-Ho ; Han, Jeong-Woo ; Park, Young-Jun ; Lee, Young-Soo ;
Journal of The Korean Society of Manufacturing Technology Engineers, volume 20, issue 5, 2011, Pages 673~678
For the wind-diesel hybrid electric power generation system equiped with two diesel generators, the diesel power sharing is studied analytically and a power sharing technique of less fuel consumption is developed. Based on the technique, as example, a diesel power sharing algorithm is suggested for two diesel generators of capacity 500Kw(200Kw+300Kw).