China double stage vane pump supplier

Two-stage vane pump and double vane pump structure and working principle

1. Two-stage vane pump

Two-stage vane pump refers to the two pumps installed on the same drive shaft in series to form the oil circuit relationship of the front and rear stages, that is, the oil outlet of the former pump is the oil inlet of the latter pump, and the two vane pumps are installed In a pump body and connected in series on the oil circuit.

The working principle of the two-stage vane pump is that the rotors of the two single-stage vane pumps are installed on the same transmission shaft, and when the transmission shaft rotates, the two rotors are driven to rotate together.

The first-stage pump absorbs oil from the oil tank through the oil suction pipe, and the output oil is directly sent to the oil suction port of the second-stage pump, and the output oil of the second-stage pump is sent to the working system through the pipeline, thus forming a front and rear stage. Oil supply relationship.

Suppose the output pressure of the first-stage pump is p1, and the output pressure of the second-stage pump is p2, then the final output pressure of the pump is p1+p2:

But this requires a basic condition: the output flow of the first pump should just meet the needs of the input flow of the second pump, otherwise it will cause cavitation in the oil, cause noise, and reduce the efficiency of the pump. Since the curves and widths of the inner walls of the stators of the two pumps cannot be made the same, the capacities per revolution of the two single-stage pumps cannot be completely equal.

2. Double stage vane pump

The double vane pump is composed of two independent vane pumps installed on the same drive shaft. The external oil circuits of the two pumps are independent of each other. Two pumps can share the same inlet port, but their pressure ports are independent. The two pumps can be installed in the same casing or can be provided with separate casings. It is a duplex pump in which two pumps share the same casing but have independent oil outlets, and they are jointly driven by the drive shaft 7.

This kind of double-vane pump is often used in mechanical transmissions with fast-moving and slow-working feed requirements. At this time, the double pump is often composed of a small flow pump and a large flow pump. When fast movement is required, oil can be supplied by a large-flow pump, or two pumps can supply oil at the same time; when a slow working feed is required, oil can be supplied by a small-flow pump, and the large-flow pump can be unloaded at the same time to save power And prevent the heating of the oil. This kind of pump often adopts a double-connected structure of a low-pressure large-flow pump and a high-pressure small-flow pump.