Mfr of chipboard etc. by stepped pressing between steel strips

摘要

The material which is to be compressed is fed between belts with inlet gap which gradually reduces over a first stretch (a) The gap between the belts is controlled by heated plates which are moved against the belts. The press plates act against rollers which engage with the belts. The first stretch (a) is followed by second, third and fourth stretches (B,C,E). Over the third stretch (C) no pressure is exerted on the belt so that the material can expand again, which allows the density distribution of the end product to be controlled. The edges of the entry and exit sections of the third stretch (C) lie at an angle of (beta) and (beta1) which have tangents of approximately 0.05 for a vertical increase in thickness of up to 10 mm.