A Parametric Study for the Upset Forging of Large Ingot

대형 Ingot의 Upset 단조기술에 관한 연구

  • 박승희 (현대중공업(주) 기술개발본부 마북리연구소) ;
  • 유성만 (현대중공업(주) 기술개발본부 마북리연구소) ;
  • 신상엽 (현대중공업(주) 기술개발본부 마북리연구소)
  • Published : 1999.02.01

Abstract

The upset forging stage is the initial work in the forging process. It is used to remove the segregation and cavities of the ingot. Specially in handling large sized ingot, an improper upset forging can cause serious surface tearing. However, there is no detail reference for stable upset forging work. To resolve this difficulty, we studied several factors such as upset forging time, temperature varation of ingot, damage, load and stain rate etc., by using the rigid-plastic finite element approach available in the DEFORM code. Numerical simulation results indicated that: the load value of upset forging works shows severe decreasing trend at a certain point, same as strain rate. Also defects were found to be concentrated around the upper and lower portions of the ingot. With these results, we can estimate a guideline for stable upset forging work.

Keywords

References

  1. Metal Forming and the Finite-Element method Shiro Kobayashi;Soo-Ik Oh;Taylan Altan
  2. Measurement and Analysis of Heat Transfer and Friction During Hot Forging Paul R.Burte
  3. Metal Forming Fundamentals and Applications T.Altan;S.I.Oh;H.L.Gegel
  4. Trans. ASME, J. Engr Industry Flow Stress Determination for Metals at Forging Rates and Temperatures J.R.Douglas;T.Altan
  5. Metals Handbook(9th ed.) v.14 Forming and Forging ASM International
  6. Journal of the Iron and Steel Institute The Closing of Internal Cavities in Forgings by Upset A.Tomlinson;A.Met.;A.I.M.;J.D.Stringer
  7. M.S.thesis, The Ohio State University Investigation of Defect Formation in a 3-Station Closed Die Forging Process Jenkins,B.