Piston pump
Between valve block (6) and drive mechanism of a pump, angularly movable oscillating line pipes (8) are arranged which connect the working chambers of the plunger (3) to the pump working chambers (7) arranged between intake and pressure valves. When pumping hot media to the drive mechanism (1), a temperature drop occurs inside the oscillating line pipes (8) so that the seals (5) of the plunger (3) are exposed only to relatively low temperatures. So that the valve block (6) expanding from the drive mechanism (1) under the thermal load does not transmit any inadmissible transverse forces to the cylinder parts (4) of the plunger (3), a transverse web (12) providing intermediate support for the oscillating line pipes (8) is arranged which, through interaction with the valve block (6) forces the oscillating line pipes (8) into variably separated relative positions in such a way that the ends of the oscillating line pipes (8) on the drive mechanism side have an almost constant transverse separation (S). <IMAGE>