TABLE OF CONTENTS The important variables in the technical components of deep drawing dies are the punch corner radius, the die ring profile, the clearance between punch and die ring, and the configuration of the surfaces of the die rings and the blank holder that are in contact with the blank.
The die ring profile substantially influences both the deep drawing process and the quality of the drawn workpieces. Because the material is pulled over the profile, it is necessary that the die ring profile have an optimum value. The most frequently used draw rings use a corner radius or conic profile, even though other kinds of draw rings are used as well.
A draw ring with a corner radius ( R p) is the most frequently used for the first drawing operation without a reduction of the thickness of the materials, whether a blank holder is used or not. Fig. 11.1 shows a deep drawing die with a draw ring having a corner radius.
A draw ring with a corner radius, as shown in Fig. 11.2, can also be used for subsequent drawing operations without any reduction in the thickness of the materials if a blank holder is not used. If a blank holder is used, however, the conditions for drawing are much better using a draw ring with a conic profile than one with a corner...
