Title: A method for force reduction in heavy duty bending

Authors: Joost R. Duflou, Richard J. Aerens, Stephan Masselis, Jean-Pierre Kruth

Addresses: Department of Mechanical Engineering, Katholieke Universiteit Leuven, Celestijnenlaan 300B, Leuven 3001, Belgium. ' WTCM-CRIF, Celestijnenlaan 300C, Heverlee 3001, Belgium. ' WTCM-CRIF, Celestijnenlaan 300C, Heverlee 3001, Belgium. ' Department of Mechanical Engineering, Katholieke Universiteit Leuven, Celestijnenlaan 300B, Leuven 3001, Belgium

Abstract: A trend towards thicker and larger sheet metal parts can be observed. This leads to the construction of huge press brakes. A method to reduce the bending force is to preheat locally and quickly the bending area of the thick steel plate. For this purpose a dynamic contact method has been chosen: the steel is heated by being put in contact with preheated |contact elements|. This method was experimentally tested on low carbon steel plates with a prototype setup. Reported results of the tests include achievable temperature distributions, and associated bending force. An achievable press force reduction of over 50% was demonstrated. The proposed preheating process has been simulated using the Finite Element method. Referring to the measured temperature evolutions, an appropriate value for the heat transfer coefficient could be determined. This allowed simulating the process for other combinations of plate thickness and contact element size.

Keywords: sheet metal bending; force reduction; press force; dynamic preheating; heat transfer; sheet metal forming; low carbon steel plates; finite element method; FEM; simulation; plate thickness; contact element size.

DOI: 10.1504/IJMPT.2008.022147

International Journal of Materials and Product Technology, 2008 Vol.32 No.4, pp.460 - 475

Published online: 19 Dec 2008 *

Full-text access for editors Full-text access for subscribers Purchase this article Comment on this article