1. Basic Concept of the Pumping Rod The pumping rod, as the name suggests, is a slender component that connects the downhole pump to the surface drive mechanism, driving the downhole pump through reciprocating motion. It is typically made of high-strength alloy steel to withstand significant tensile and compressive forces, as well as alternating loads, ensuring stable long-term operation in harsh downhole environments. Pumping rods can be categorized into various types, including solid rods, hollow rods, and specially structured rods, to meet different geological conditions and extraction requirements. A sucker rod is a steel rod, typically between 25 and 30 feet (7 to 9 meters) in length, and threaded at both ends, used in the oil industry to join together the surface and downhole components of a reciprocating piston pump installed in an oil well. The pumpjack is the visible above-ground drive for the well pump, and is connected to the downhole pump at the bottom of the well by a series of interconnected sucker rods. Sucker rods are also commonly available made of fiberglass in 37 1/2 foot lengths and diameters of 3/4, 7/8, 1, and 1 1/4 inch. These are terminated in metallic threaded ends, female at one end and male at the other. 2 Working Principle of the Pumping Rod In the process of oil extraction, the pumping rod is driven by a power device on the surface (such as a pump jack) to perform periodic up-and-down reciprocating motion. When the pumping rod moves downward, it pushes the downhole pump plunger down, increasing the volume of the pump chamber and creating a negative pressure that draws crude oil into the pump. Subsequently, the pumping rod moves upward, driving the plunger upward, which decreases the volume of the pump chamber and increases the pressure, thereby transporting the crude oil through the tubing to the surface. This process repeats continuously, enabling the ongoing extraction of crude oil. 3. Technical Characteristics of Pumping Rods High Strength and High Toughness: Pumping rods must withstand significant mechanical stress and alternating loads, thus requiring materials with high strength and high toughness to ensure long-term safety and reliability during use. Corrosion Resistance: Due to the complex underground environment, which contains various corrosive media, the surface of pumping rods is often treated for corrosion resistance, such as galvanization or the application of protective coatings, to extend their service life. Good Sealing Performance: To ensure the efficiency of the pumping unit, it is essential to maintain good sealing between the pumping rod and the pump body to prevent crude oil leakage. Ease of Maintenance: To facilitate replacement and repair, the design of pumping rods must consider their disassemblability and ease of maintenance, enabling continuous crude oil extraction through a cyclical process.