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Choi, J.C.;Choi, Y.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 1997.10a
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- pp.172-175
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- 1997
The conventional closed-die forgings had been applied to the forging of spur gears. But the forgings require high forging-pressure. In this paper, new precision forging technology have been developed. The developed technology is two steps forging process. Good shaped products are forged successfully with lower forging-pressure than those of conventional forging
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박용복;양동열
- Transactions of Materials Processing
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- v.8 no.4
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- pp.384-392
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- 1999
In metal forming, there are problems with recurrent geometric characteristics without explicitly prescibed boundary conditions. In such problems, so-called recurrent boundary conditions must be introduced. In this paper, as a practical application of the proposed method, the precision cold forging of a helical gear has been simulated by a three-dimensional rigid-plastic finite element method and compared with the experiment. The application of recurrent boundary conditions to helical gear forging analysis is proved to be effective and valid. the elastic stress analysis of the die for helical gear forging has been calculated by using the nodal force at the final stage obtained from the rigid-plastic finite element analysis. In order to obtain more precise gear products, the elastic analysis of the die after release of punch and the elastic spring-back analysis of product after ejection have been performed, and the final dimension of the computational product has been in good agreement with that of the experimental product.
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Noh T.D.;Jung S.H.;Lee Y.S.;Kwon Y.N.;Lee J.H.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2003.10b
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- pp.63-66
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- 2003
Forged gears have the obvious advantages with the greater utilisation of raw material and high productivity over the machined gears. The forged bevel gear has been used in differential gear for automotive with a high reliance. On the other hand, the studies have been continued to improve the accuracy and expand the applying areas. In this paper, a whole manufacturing process for forged gear from die design and cold forging to heat-treatment was introduced. The stress and elastic deformation for forging die have been analysed by the 3D-FEM-package. The real elastic deformation of die was measured by the strain-gages. The elastic deformation of die was reached to 1mm, in terms of the present study. The analysed quantitative dimension of die was taken into consideration into the CAD/CAM data for forging die.
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임창수;서성렬;이민철;김주현;전만수
- Journal of the Korean Society for Precision Engineering
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- v.15 no.10
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- pp.51-57
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- 1998
In this paper, a computer aided process design technique, utilizing a forging simulator and a commercial CAD software, is presented together with its related design system for cold-former forging of ball joints. The forging sequence design is carried out through user-computer interaction by using design templates, design database, experience or knowledge-based rules and some basic laws found in the literature. The forging simulation technique is used to verify the process design. The detail designs including die set drawings and die manufacturing information are automatically generated. It has been shown that the engineer ing and design productivity is much improved by the presented approach in the practical standpoint of process design engineers.
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Song D. H.;Park Y. B.;Lim S. J.;Kim M. E.
- Proceedings of the Korean Society for Technology of Plasticity Conference
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- 2001.10a
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- pp.220-223
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- 2001
Until now, the clamp yoke of automobile has been largely manufactured by hot forging or burring process. Through the study, the precision cold forging process for clamp yoke has been analysed by using rigid-plastic finite element analysis code, DEFORM-3D. It has shown various results of the FEM simulation. An engineer should select the proper process considering the amount of product.
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Seo, Y.H.
- Transactions of Materials Processing
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- v.30 no.4
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- pp.172-178
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- 2021
The cold forging process induces material deformation in an enclosed space, generating a very high forging load. Therefore, it is mainly designed as a multi-stage process, and fatigue failure occurs in forging die due to cyclic load. Studies have been conducted previously to quantitatively predict the fatigue limit of cold forging dies, however, there was a limit to field application due to the large error range and the need for expert intervention. To solve this problem, we conducted a study on the introduction of a real-time forging load measurement technology and an automated system for quantitative prediction of die life cycle. As a result, it was possible to reduce the error range of the quantitative prediction of die life cycle to within ±7%, and it became possible to use the die life cycle calculation algorithm into an automated system.
https://doi.org/10.5228/KSTP.2021.30.4.172 인용 PDF KSCI HTML