A mud pump is a machine used during drilling to deliver mud or water, or other flushing fluid, into the borehole. Mud pumps are an important component of drilling equipment.
In commonly used positive circulation drilling, it delivers the surface flushing medium-clean water, mud, or polymer flushing fluid-under pressure through a high-pressure hose, swivel, and the center hole of the drill string directly to the bottom of the drill bit. This cools the drill bit and removes and transports the cut rock cuttings to the surface.
Common mud pumps are piston or plunger type. A power unit drives the pump's crankshaft to rotate, and the crankshaft, through a crosshead, drives the piston or plunger to reciprocate within the pump cylinder. The alternating action of the suction and discharge valves achieves the purpose of pressurizing and circulating the flushing fluid.