Rotary piston pump, in particular discharge gear pump

摘要

A discharge gear pump for discharging a corrosive polymer melt under great mechanical loading is described. The problem lies in the material pairing in the area of the bearing bushes mounted in the side plates of the pump housing and of the drive shaft made of corrosion-proof steel. In order to avoid the mechanical wear on the shaft, co-running armour bushes are arranged between the bearing bushes and the drive shaft. The toothed wheel and the armour bushes arranged on both sides on the drive shaft are made either as one part or from a number of components, and in particular from a sintered material which is corrosion-resistant and after its hardening has an adequate hardness of more than 58 HRC.