Pumping unit is a kind of machinery and equipment used to extract petroleum, commonly known as "kowtow machine". The pumping unit is the most important lifting equipment in the rod pumping system. According to whether there is a beam, it can be divided into beam pumping unit and beamless pumping unit. 
The basic characteristics of the beam pumping unit are simple structure, easy to manufacture, and convenient to use. In particular, it can run around the clock in the oil field for a long time and is reliable in use. Therefore, although it has the disadvantages of large acceleration, poor balance effect, low efficiency, large volume and heavy weight during long strokes, it is still the most widely used pumping unit.