Blank Development and Metal Flow Analysis for Multi-Stage Drawing of Box Shaped Stampings

Blank development is the basis for calculating the material cost and hence the product cost, at the quoting stage. Understanding the metal flow under the binder is a critical activity during the tooling design stages, as well as during phototyping. The paper describes a computer aided blank development and metal flow analysis system, that will assist in performing the functions described above, before the tools are built, for box shaped parts drawn in multi-stage forming operations with a flat punch face, and a flat binder.

Development of the minimum blank shape, using the SLF technique for shrink flanged components is not new. The paper addresses the extension of the approach to:

1. i.
   multi-stage forming operations and,
2. ii.
   the incorporation of the effect of thickness changes on the blank shape. Applications are given in the paper using the computer program BLANKDEV.