• Transactions of Materials Processing
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• v.20 no.2
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• pp.110-117
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• 2011

The purpose of this work is to develop of a press forming process for mobile phone battery cover as an alternative to the current manufacturing process by laser welding. This press forming process consists of a combination of bending, side pressing and side bending operations. The dimensional error for each process was investigated by finite element(FE) analysis and the Taguchi optimization method. The spreading of the cover width in the side pressing process was adjusted by modifying the blank shape with a notch. The over-bending method was adopted to compensate the spring-back which occurs after bending. Forming experiments were performed to verify the reliability of the developed press forming process. In addition, the strength of the product was evaluated to verify the suitability of the battery cover manufactured with this new press forming process. The results of the forming experiments indicate that the dimensional accuracy of the battery cover is within the required tolerance. The strength of the battery cover was evaluated to 547N which is larger than required strength of 400N.

• Proceedings of the KSME Conference
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• 2007.05a
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• pp.544-548
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• 2007

In general, final width of hot strip should be accomplished in this stage because width reduction of strip hardly appears during typical finishing mill. However, it is difficult to control the width of strip in the roughing mill process as the horizontal rolling of strip is subsequently performed after the vertical rolling. It is therefore important to obtain the deformation rolling direction on strip width to minimize the width spread of strip during horizontal rolling after vertical rolling. Generally there is Sizing press type and Edger-roll type. The width reduction process in sizing press has small amount of width spread compared with the edger. However, productivity by the sizing press process is much lower than those of the edger. In this study, sizing press and Edger-roll process parameters in a sheet rolling mill were set at specified values and the effect of the change in these parameters on product quality and process performance were evaluated.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.08a
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• pp.41-52
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• 2003

The tendency of current die manufacturing is focusing into development period shortening and panel quality improvement. This brings change of manufacturing process. In existing process, depended on experience, we were faced on a limit of sufficiency in this focus. Thus, we have attempted to make a conquest of that by constructing a process of CAE. Our attempt apply not only draw die formability but also trimming and flanging die formability with simulation of sheet metal. In this paper, we publish effects that were obtained by constructing a process.

• Korean Journal of Computational Design and Engineering
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• v.14 no.5
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• pp.314-322
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• 2009

In these days, automotive companies are trying to develop new manufacturing technologies and paradigms for rapid product development and production. The press die development process account for 40% of entire vehicle development process, and tryout process usually takes 3 to 4 months, and it is the biggest time portion out of dies manufacturing. Therefore, the effective tryout management system is essential to reduce time and cost of automotive press die production. This paper suggests improved process and practical application of tryout management using ubiquitous technology, and shows the results such as shorten time, improved quality and supporting of lifecycle engineering of press die.

• Journal of the Korean Graphic Arts Communication Society
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• v.27 no.1
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• pp.107-118
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• 2009

The printing industry is getting more digitalized and integration. It has enabled the interactive information and networking from Pre-Press, Press, to the Post-Press. These are efficient management and the improved process and productivity are getting more important. Such trends improved in the functionality and automation. This paper tries to find out how technology for CIP3/4-based process may be applied and resolved. Such subject includes the domestic and international cases regarding each manufacturer's CIP3/4 technology types. Another purpose is to emphasize on the needs to establish the environment. Under this environment, it is possible to integrate network in exchangeable form through JDF standard format after CIP3/4. Based on the data from this study, it is expected to collect further substantial data which is related to the domestic printing company's CIP4 operation. It will be also possible to perform subsequent studies on the proper variables of the market segment. CIP4 stands for "International Cooperation for Integration of Prepress, Press and Post-press, it is an association of around forty international companies, mostly manufacturers of prepress, press and post-press, as well as suppliers and users. In this paper, we studied on the acting application of CIP4 workflow.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2008.10a
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• pp.190-193
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• 2008

Thick pipes which have large thickness have been used in fields of ocean and industrial plants, and for oil pipelines, water pipes and pipe arrangement. In manufacture of the pipes, roll bending process has been used mostly. However, studies on the pipe forming processes using brake press have been performed in recent days. Normally, the brake press has high aspect ratio, so analysis of structural integrity should be conducted. In this study, the evaluation of structural integrity of the brake bending press was carried out for thick pipe forming process.

• Proceedings of the KSME Conference
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• 2008.11a
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• pp.529-533
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• 2008

Thick pipes have been used in fields of ocean and industrial plants, and pipe arrangement of oil and water pipelines. Mostly, roll bending process has been used in manufacture of the pipes. Recently, however, studies on the pipe forming processes using brake press have been performed. Normally, the brake press has high aspect ratio, so structural integrity evaluation should be conducted. In this study, finite element analysis of structural integrity for the brake bending press was carried out for thick pipe forming process.

• Transactions of Materials Processing
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• v.20 no.8
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• pp.588-594
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• 2011

A new manufacturing process is presented for automotive drive plate using a boron-containing carbon steel sheet, which is hot-formed and press quenched. Particular attention was given to the capability of the process in minimizing dimensional change.

• Composites Research
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• v.33 no.2
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• pp.76-80
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• 2020

In this study, vacuum bag hot-press (V-HP) process can be used as an out-of-autoclave (OOA) process by improving the inefficient process of the autoclave forming method with excellent physical properties and surface quality. A carbon fiber composite was molded via V-HP process and analyzed the physical properties and microstructures between composites manufactured by autoclave (AC) process and hot-press process (HP). The tensile strength of the composite materials using the V-HP process was 320.6 MPa and the AC process samples found to be substantially close to the tensile strength of 335.3 MPa. As a result of confirming the surface quality of the composite material using SEM, it was confirmed that in the V-HP process, the removal state of pores due to volatile solvent in the resin was slightly lower than that of the AC process, but it had a considerably superior surface compared to the HP process.

• Transactions of Materials Processing
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• v.25 no.2
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• pp.116-123
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• 2016

Press-brake bending is used to shape flat and thick plates into a targeted circular configuration without excessive localized thinning or thickening. A brake bending press called 'a knife press bending apparatus' has been widely adopted to manufacture thick, large and long pipe from initially thick plate. Submerged Arc Welded (SAW) pipes are also produced by employing press-brake bending. These pipes are mainly used for oil, natural gas and water pipelines. The principal process variables for press-brake bending can be summarized as stroke of the press-brake knife, the distance between both roll in the lower die, and the feeding length of the plate. Many combinations of these process variables are available, thus various pipe diameters can be realized. In the current study, a series of repetitive numerical simulations by feeding a thick plate with initial thickness of 25.4mm were conducted with the consideration of elastic recovery. Furthermore, an index for SAW pipe production is proposed which can be widely used in industry.