Drilling pumps were formerly known as "mud pumps". If the whole drilling operation process is compared to human life activities, then the drilling pump, like the human heart, is the source of continuous circulation of drilling fluid from the ground to the bottom of the well, and then from the bottom of the well back to the surface. Drilling pumps are an important part of drilling equipment.

In commonly used rotary drilling, it is to send the surface washing medium, drilling fluid, under a certain pressure, through the high-pressure hose, swivel and drill string center hole, straight to the bottom of the drill bit, so as to achieve the purpose of cooling the drill bit, removing the cut rock chips and transporting them to the surface.

The commonly used drilling pump is piston type or plunger type, the crankshaft of the pump is driven by the power machine, and the crankshaft is driven by the crosshead and then driven by the piston or plunger in the pump cylinder to reciprocate. Under the alternating action of suction valve and discharge valve, the purpose of pressure delivery and circulation of drilling fluid is realized. During the drilling process, if the drilling pump does not work properly, a downhole drilling accident will occur, just like the human heart has stopped beating.

The classification of drilling pumps can be divided into single-acting drilling pumps and double-acting drilling pumps according to the form of action, and can be divided into three cylinders and five cylinders according to the number of cylinders.