Piston assembly is the major part of the mud pump fluid end. The discharge pressure of mud pump is generated by the up-and-down motion of the piston in the cylinder. Small piston—high pressure and low flow rate; Big piston—low pressure and high flow rate. Metric pump and inch pump adopts metric piston and inch piston respectively. Generally, φ170, φ160, φ150 and 6″, 6-1/2″, 7″, etc., is used.

The inner hole of F500 piston of the metric pump isφ25.4; The inner hole of F800--1300 piston isφ42. The inner hole of inch piston isφ38.1.

Material: piston core 42CrMo; Rubber sheet: Buna-N rubber or polyurethane