Structural Analysis Of Multi-stage Pumps

The multi-stage pump mainly consists of four parts: stator, rotor, bearings, and shaft seal:
1. The stator part of a multi-stage pump mainly consists of a suction section, a middle section, a discharge section, and a guide vane, which are clamped by tension bolts to form a working chamber. D-type pumps generally have horizontal suction and vertical upward discharge; When injecting water into an oilfield, the inlet and outlet of the pump are all vertically upward. The inlet and outlet of the DG multi-stage pump are both vertically upward.
2. The rotor part of a multi-stage pump mainly consists of a shaft, impeller, balance plate, and shaft sleeve. The axial force is balanced by a balance plate.
3. The multi-stage pump bearings mainly consist of bearing bodies, bearings, and bearing glands, etc. The bearings are lubricated with grease or thin oil.
4. The shaft seal of the multi-stage pump adopts a soft packing seal, mainly composed of the sealing box body, packing, water blocking ring, etc. on the inlet section and tail cover. The water seal of the D-type pump comes from the pressure water inside the pump. The DG pump seal water comes from external water supply.
5. The multi-stage pump rotates and is directly driven by the prime mover through an elastic coupling. Looking at the pump from the original engine end, the pump rotates clockwise. The DG type pump is a horizontal single suction multi-stage segmented centrifugal pump. For transporting clean water (with impurities less than 1% and particle size less than 0.1mm) or other liquids with physical and chemical properties similar to water. The temperature of the medium conveyed by the D-type pump is less than 100 ℃, suitable for mining drainage, oilfield water injection, factory and urban water supply and drainage, and other occasions. Oilfield water injection pumps use different materials based on the corrosiveness of the medium. The DG type pump delivers medium temperatures below 120 ℃ and is suitable for various types of boiler feedwater.