A Process Sequence Design of Multi-Step Cold Extrusion Process for Hollow Parts



Conventional multi-step extrusion processes with solid billet are examined by the rigid-plastic finite element method in order to provide criteria for new process sequence for hollow parts. Two examples are taken for the analyses such as the current three-stage cold extrusion process for a hollow flange part and five-stage process for manufacturing an axle housing. Based on the results of simulation of the current three-stage and five-stage manufacturing processes, new design strategy for improving the process sequences is developed simply by replacing the initial billet from solid to hollow one. The developed new process sequences are applied for simulation by FEM and they are compared with the existing processes to confirm the usefulness of new process sequences with hollow initial billets. The results of simulation show that the newly proposed process sequences with hollow billet instead of solid one are more economical way to manufacture required parts, respectively.





Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie




J. H. Shim et al., "A Process Sequence Design of Multi-Step Cold Extrusion Process for Hollow Parts", Materials Science Forum, Vols. 475-479, pp. 4195-4198, 2005


January 2005




[1] H. S. Kim and Y. T. Im: J. of Mat. Proce. Technol. Vol. 54 (1995), p.271.

[2] C. Park, J. Y. Lim and B. B. Hwang: J. of Mat. Proce. Technol. Vol. 75(1998), p.33.

[3] K. Osakada, X. Wang, S. Hanami: J. of Mat. Proce. Technol. Vol. 71(1997), pp.105-112.

[4] Korea Flanges Co. Ltd: To Mark Progress Controlled Quality(1992), p.10.

[5] S.W. Choi and Y.S. Lee: Met. Mater. -Int. Vol. 8, No. 1 (2002), p.15.

[6] S. Kobayashi, S. I. Oh, T. Altan: Metal forming and the finite-element method (Oxford University Press, Oxford 1989), p.32.

[7] Air Force Materials Laboratory: Forging Equipment, Materials and Practices (Metals and Ceramics Information Center, 1973), p.64.

[8] E. Paul De Garmo: Mat. and Proc. in Manuf. (Macmillan, New York 1967), p.27.

[9] J. Datsko: Mat. Prop. And Manuf. Proc. (Malloy, Ann Arbor 1966), p.31.

[10] American Society for Metals, Source Book on Cold-Forming (Library of Congress Cataloging in Publication Data, 1975), p.246.

[11] T. Huziyoshi, Die & Mould (Daily Technology Press, Tokyo 1989), p.446.

[10] [20] [30] [40] [50] [60] 0 5 10 15 20 25 Stroke from BDC (mm) Pressure (MN).

1000 2000 3000 4000 5000 6000 Pressure (ton).

[54] mm.

[58] mm Proper press capacity.

[20] [40] [60] [80] 100 120 0 100 200 300 400 500 Stroke from BDC (mm) Pressure (MN).

2000 4000 6000 8000 10000 12000 Pressure (ton) First Operation Final Operation Proper press capacity (a)flange (b) axle-housing Fig. 4 Pressure-stroke relationship for the proposed process with selection of the press equipment.