What is Mud Pump Piston? The mud pump piston is one of the main parts of the fluid end system of the mud pump, and also one of the vulnerable parts in drilling work. The discharge pressure of mud pump is produced through the reciprocating rectilinear motion of the piston assembly in the piston. The piston assembly is composed of a piston core, rubber, spring, pressing plate, etc.. Mud pump piston and cylinder liner constitute a pair of dynamic sealing and sealing components are assembled on the