Method of controlling mandrel in a tube-extruding press

The invention relates to a method for adjusting the position of a mandrel, which is situated in a hydraulic punch consisting of a cylinder and a ram that form a mandrel cylinder, in an extrusion press for producing pipes, which are extruded from blocks that are loaded into a receiving device situated upstream of the extrusion press and are punched using the mandrel. The invention is characterised in that the mandrel cylinder is driven directly by pumps, which are set for a pre-calculated throughput that is dependent on the press speed, and that an additional throughput is added to the pre-calculated pump throughput. To adjust the position of the mandrel, a control valve that acts on the ring side of the mandrel is connected to a tank.