Assessment and improvement of elementary force computations for cold forward rod extrusion

Date

2005-06-01

Author

Ocal, M
Egemen, N
Tekkaya, AE

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Two commonly used analytical force computation methods for cold forward rod extrusion are evaluated by means of precise finite element computations. The upperbound model by Avitzur based on the spherical velocity field and the model by Siebel based on a quasi-upper-bound solution are considered. It has been found that the pure deformation forces obtained by summing the ideal force and shear force terms deviate between +25% and -20% from the finite element solutions. Larger deviations, however, occur for the Coulomb-friction term in the container. A new model based on an elasto-static analysis combined with numerical analysis is suggested to compute this term. This new model supplies also the accurate pressure distribution within the container.

Subject Keywords

Mechanical engineering, Metal forming, Cold forging, Forward rod extrusion, Analytical force prediction, Finite element method

URI

https://hdl.handle.net/11511/67024

Journal

ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING

Collections

Department of Mechanical Engineering, Article

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Citation Formats

M. Ocal, N. Egemen, and A. Tekkaya, “Assessment and improvement of elementary force computations for cold forward rod extrusion,” ARABIAN JOURNAL FOR SCIENCE AND ENGINEERING, pp. 83–102, 2005, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/67024.