• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.46-49
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• 2008

Drawing process of the high carbon steel wire with high speed is usually performed at room temperature using multi pass. Tn the multi pass drawing, temperature rise affects the mechanical properties of the final product. The excessive temperature rise during the deformation promotes the occurrence of delamination, and deteriorates the torsion property and durability of wire. This paper investigates the occurrence of delamination in the wire through the torsion test and the evaluation of wire temperature. The excessive wire temperature ieads to the occurrence of delamination. Based on the calculation of the wire temperature, a new pass schedule, that can prevent the delamination due to the excessive wire temperature rise, is designed through the isothermal pass schedule.

• Transactions of Materials Processing
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• v.3 no.1
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• pp.51-62
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• 1994

Cup drawing test and U-bending test were performed to evaluate the friction characteristics of sheet materials for the different deformation modes involved in stamping process. The coefficient of friction calculated from the each test was compared to that obtained from the draw bead friction test. It was clarified that the cup drawing test could be simply used for evaluating the friction characteristic of sheet material in deep drawing process with high contacting pressure. However the U-bending test is suitable to evaluate the frictional characteristic of sheet material in bending process with low contacting pressure.

• Journal of the korean Society of Automotive Engineers
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• v.11 no.3
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• pp.49-59
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• 1989

The purpose of this paper is to obtain the effect of die lubrication in deep drawing process. The flange wrinkling is analysed by a moment equilibrium method in order to apply the optimum blankholding force to the blank. The experiment has been carried out with the high stiffness spring-type blankholder system. As the result, blankholding pressure is determined in terms of variables in deep drawing process. In the range of frictional coefficient which has been found in this experiment, there was a little difference in required blankholding force but a great difference in drawing force. It was found that the stiffness of blankholder was the major factor which influences on flange wrinkling in spring-type blankholder system.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2006.05a
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• pp.48-52
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• 2006

The drawability of AZ31B magnesium sheet is estimated at various temperatures (200, 250, 300, 350 and $400^{\circ}C$), and forming speed (20, 50, 100 mm/min), thickness (0.5, 0.8, 1.0, 1.4 mm). The deep drawing process of circular cup and square cup were used in forming experiments. Experimental and FEM analysis are performed to investigate drawability and affection of controlled blank holding force. Through the controlled blank holding force, drawability was improved. This result is verified by FEM analysis. Through the observation of microstructure, the main cause is investigated as a quantity of the dynamic recrystallization.

• Journal of KIBIM
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• v.10 no.4
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• pp.22-31
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• 2020

Shop drawing tasks conducted after finishing coordinated or engineering design have great influences on the quality and cost of a project. However, despite the development of commercial BIM applications, shop drawings have mainly produced manually in certain engineering fields. Incorrect shop drawings with human errors have occurred various problems such as cost overrun, time delay and reworks. An automated shop drawing publishing from BIM is expected to resolve these problems. Despite attempts for automate shop drawing production, the field of mechanical, electrical and plumbing (MEP) is yet regarded challenging due to complexity of components and connection. In this research, we develop a process for automated producing 3D MEP shop drawings in BIM environment as following steps: to analyze conventional MEP shop drawing process, to identify detailed process that can be automated, to classify existing MEP objects and assign codes usable in BIM, and to develop an application. The validation of automated process is conducted against 10 clean room projects in which MEP is more complex and its cost is higher than other projects in terms of productivity and workers' satisfaction. Results show that the number of manpower for shop drawing is reduced by 30%, and the working time is shortened by 31%. Personal opinions of involved practitioners is interpreted as positive as the average rate of agrement on practicability, easy-to-use and necessary retouch tasks is around 66%.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.03a
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• pp.26-29
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• 1999

Process design for elliptically shaped deep drawing products is various according to size shape and specification of products. This study presents two approaches to design the preform that is a key process for elliptically shaped products, One of these is that cross-section of punch is circular. Another is that for the improvement of characteristics for final products the cross-section of the punch is similar to rectangular shape. After forming the preform process design of top-part drawing is the same. In the study blank shape and dimension are obtained by applying a numerical formula and surface area constancy.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.10a
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• pp.1082-1086
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• 2004

Since the sheet forming of Mg alloy has many difficulties due to the low formability, many forming conditions need to be selected properly. Especially, the process variables should be investigated to increase the formability, such as, forming temperature. In this paper, the effects of forming process variables has been investigated using the bending and deep drawing process. A simple U-bending designed for mobile part could be formed in room temperature and springback amounts are surveyed. On the other hand, square cup part couldn't be formed in room temperature due to the low formability. Therefore, the effects of forming temperature are investigated in deep drawing process for square cup part. As a experimental and FEM results, the optimum forming temperature is presence and formability in a higher temperature is less than that of lower temperature. Above experimental results are compared with the FEM analysis and well coincided with the experimental results. Therefore, more detail investigations could be progressed to select more appropriate process conditions by the FEA.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.8
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• pp.59-70
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• 1999

This paper deals with automated computer-aided process planning by which designers can determine operation sequences even if they have little experience in the design of press working products. The computer-aided process planning in hot forging, deep drawing and blanking requires many kinds of technical and empirical skills based on investigation and collection of the knowledge of their processes. An approach to the CAPP system is based on the knowledge-based rules and the process knowledge base consisting of process planning rules is built. The methodology adopted to develop the system is elaborated in this paper. This system has been written in AutoLISP on the AutoCAD with a personal computer and provides powerful capabilities for process planning of hot forging, cold forging, deep drawing and blanking products.

• Journal of the Korea Institute of Building Construction
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• v.3 no.2
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• pp.111-118
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• 2003

Steel frame construction is divided into subsidiary materials with column, beam, girder and bracing. After these are processed in factory for using installing in construction field. These prefabricated furniture is very important in accordance with design drawing about processing and prefabricating. In the case of design process using information transmission in blueprint, omission of material number, processing measure and finishing material, or discordance of each structure drawing and selecting incongruent structural material generated an error in the process of design. These error caused delaying time and increasing cost and increasing safety accident in the steel-structure work operating process. therefore, design process should consider problem of operating process.

• Transactions of Materials Processing
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• v.8 no.4
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• pp.340-346
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• 1999

Circular drawbead forming and drawing characteristics of CO2 laser welded SPC1 blanks are investigated by experiments and numerical analysis. During the drawbead forming process, the distributions of major strain on upper and lower skins of the specimens are measured. During the drawing process, the drawing forces and the strain distributions are investigated. For the numerical analysis. DYNA3D and SGTAS, a developed rigid-plastic finite-element computer program are used. Numerical results predicted the deformation characteristics well in comparison with experiments. It is concluded that the strains and restraining forces during the forming and the drawing processes show different patterns according to the combination of welded blanks.