3 Fundamentals of press design

Presses used for solid forming
adequate clamping. In this case, cold sizing of the appropriate surfaces is
an essential pre-requisite for successful further processing (Fig. 6.8.13).
Sintered parts are also frequently subjected to a subsequent compacting
or sizing process in order to compensate for warping caused by heat
treatment (Fig. 6.8.14). All these operations require a large forming
force, coupled with minimal machine and die deflection. Due to its
favorable force distribution, the knuckle-joint bottom drive press has
been shown to offer the most suitable forming system for coining applications.
The basic principle of this drive type is described in Sect. 3.2.2
and 6.8.2 (cf. Fig. 3.2.5).
Compared to presses for solid forming, the slide stroke and work
length can be substantially shorter. Sizing is generally performed in a
single station, so allowing the die mounting area or the press bed to be
smaller. Ejector systems in the slide and press bed are only necessary for
coining work.
Cutlery embossing presses
In addition to possible applications already outlined here, this type of
sizing press is also used with a good degree of success for the forming
and embossing of cutlery. This operation allows even the finest chiselling
effects to be precisely embossed.
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998
Fig. 6.8.13
Coined forgings
523