There are several classifications of oil pumps

When the pump is filled with liquid, the impeller rotates to generate centrifugal force, and the liquid in the impeller channel is thrown to the periphery under the action of centrifugal force, and flows into the pump casing to form a vacuum in the center of the impeller. The liquid is sucked in by atmospheric pressure. The pool flows into the impeller. In this way, the liquid is continuously sucked in and out. The liquid that gains energy in the impeller has greater kinetic energy when it flows out of the impeller. These liquids are collected in the spiral pump casing and convert the kinetic energy into pressure energy in the diffuser behind. The types of centrifugal pumps can be divided into:
　　(1) Centrifugal pumps can be divided into single-stage pumps and multi-stage pumps according to the number of working impellers.
　　(2) According to the working pressure, it can be divided into: low pressure pump, medium pressure pump and high pressure pump.
　　(3) According to the impeller water inlet method, it can be divided into: single suction pump and double suction pump.
　　(4) According to the joint seam of the pump casing, it can be divided into: horizontal split pump and vertical joint surface pump.
　　(5) According to the position of the pump shaft, it can be divided into: horizontal pump and vertical pump.
　　(6) According to the way in which the water from the impeller is led to the extrusion chamber, it can be divided into: volute pump and guide vane pump.
　　(7) According to whether the pump speed can be changed, it can be divided into: fixed-speed pump and speed-regulating pump.

Definition and classification of pumps

　　Pump is a device used to convert the mechanical energy of the prime mover into the kinetic energy and pressure energy of the liquid. Pumps are generally used to transport liquids, which can be sent from a low position to a high position, or from a low pressure container to a high pressure container.
　　The types of pumps can be divided into:
　　⑴ Vane pump Centrifugal pump, axial flow pump, mixed flow pump, vortex pump, self-priming pump.
　　⑵ Positive displacement pump Gear pump, screw pump, piston pump.
　　⑶ Other types of pumps, jet pumps, vacuum pumps.
　　Pump working principle and classification

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