Walking Beam Pumping Unit

The pumping unit is a type of machinery used for oil extraction, commonly known as a ‘nodding donkey.’ It uses pressurization to extract oil from a well. During the upstroke of the pumping unit, the elastic contraction of the tubing moves upwards, driving the mechanical deblocking oil extractor upwards, which then strikes the sliding sleeve to produce vibrations; simultaneously, the forward check valve closes, and the diameter-changing piston assembly seals the oil. During the downstroke of the pumping unit, the elastic expansion of the tubing moves downwards, driving the mechanical deblocking oil extractor downwards, which again strikes the sliding sleeve to produce vibrations; simultaneously, the reverse check valve partially closes, while the diameter-changing piston assembly continues to seal the annular oil passage of the oil sleeve, forming a high-pressure area below the reverse check valve. This movement creates a reverse impact force on the oil flow channel within the formation.