Page 41 - Module DMV20173

3.0 SHEET METAL PROCESSES

Figure 3.11 The examples of the use of shear angles on punches and dies.

3. Compound dies

1. Several operations on the same sheet may be performed in one stroke at one
station with a compound die.
2. Such combined operations usually are limited to relatively simple shapes,
because (a) the process is somewhat slow and (b) the dies rapidly become much
more expensive to produce than those for individual shearing operations,

especially for complex dies.
3. Fig 3.12 shows the schematic illustrations: (a) before and (b) after blanking a
common washer in a compound die. Note the separate movements of the die (for

blanking) and the punch (for punching the hole in the washer); (c) Schematic
illustration of making a washer in a progressive die. (d) Forming of the top piece
of an aerosol spray can in a progressive die. Note that the part is attached to the
strip until the last operation is completed.

BPLK 73 DMV 20173