A Die Load Prediction and Die Plate Balancing Technique for the Selection of Presses for Sheet Metal Stampings

The paper describes a methodology, developed for process engineering at the quoting stage, for matching the press requirements with the tooling requirements in the quest for achieving a quality pressing, with low tooling and press maintenance costs.

The starting point is the process plan of the part. The approach is based on subdividing the deformation of the part within a station into elemental deformation regions. The load-displacement diagram for each elemental region is calculated individually, and then totalled to estimate the total load-displacement curve for each forming station. The total energy requirements, as well as the change of the load centre during the stroke for each forming station, is then calculated. The procedure also incorporates the effect of change of timing (e.g. staggering of actions).

The approach is then extended for the case of multiple dies acting on the same press (e.g. transfer press and progressive tooling). The information forms the basis for the selection of the press.