3 Fundamentals of press design

486 Solid forming (Forging)
Fig. 6.7.1 Four-station die holder with hydraulic die clamping and closing system
in the second station
die. However, for warm forming and in some cases also for cold forming,
the use of single die holding sleeves is preferred. Thus, the thermal
expansion is absorbed in each individual die holder, independent of
other die stations. Using a suitable cooling device, it is possible to prevent
the motion of die block, as a result of thermal expansion, relative
to the die halves mounted on the slide.
In principle, the layout of the upper die is similar. However, additional
wedge adjustment devices (Fig. 6.7.2) are located in the head plate.
These are used for individual height adjustment of the dies. The wedge
adjustment devices have an adjustment height of about 3 to 5 mm.
Metal Forming Handbook / Schuler (c) Springer-Verlag Berlin Heidelberg 1998