3 Fundamentals of press design

3 Fundamentals of press design
3.4 Changing dies
3.4.1 Die handling
Devices used for the fast exchange of dies help to reduce set-up times,
allowing the economical production of different components even
where small batch sizes are required. Small and medium-sized forming
and blanking dies are transported within the stamping plant using
cranes, forklifts or other industrial trucks. The transportation of largerscale
dies into the press and their alignment call for special die changing
fixtures, as the dies cannot be deposited directly on the press bed.
Trouble-free die change is only possible if the upper and lower dies are
perfectly centered. In addition, it must be possible to deposit the dies
outside the press. The purpose of die changing fixtures is to simplify
and accelerate transport into the die mounting area, to ensure simple
handling of the pressure pins for the draw cushion, and to permit fast,
reliable clamping of dies.
Swivelling brackets
A swivelling bracketis a low-cost die changing fixture for the transport of
the die into the press. Such fixtures can be used up to a die weight of
around 6t. In the case of dies weighing up to around 2t, insertable
brackets suspended from retaining hooks located in the press bed are
used. When higher die weights are involved, support feet, where possible
fitted with rollers, are essential. Double-jointed swivelling brackets
can be turned into a parked position after die change (Fig. 3.4.1). It is
possible for dies to be manually pushed into position by one person up
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998