Hot pressed hollow vessel prodn. - has conical face punch to extrude metal along die faces

摘要

The press die (3) has a conical insert (5) and a moving punch (4). The precast blank is subjected to welding, to correct any hair line cracks that may be present on the cast surface of the top and bottom of the block. After preheating and welding, the block is placed in the die which has a conical insert of 140 deg. included angle. The punch (4) descends to a preset dimension (8) which forms the base of the vessel. The precast blocks are cheaper than rolled bar and allow closer tolerances.