Centrifugal pump capable of reducing clearance leakage flow

Abstract

The centrifugal pump comprises a motor, a rotating shaft, a machine shell, a bottom plate, a rear cover plate, a volute, an impeller and a pump cover, the rotating shaft is connected with the motor and extends into the machine shell and the pump cover, the impeller is arranged in the volute and comprises a rotating disc, a plurality of first-stage blades, a plurality of second-stage blades, a third-stage blade and a connecting opening, and the rotating shaft penetrates through the connecting opening and is connected with the bottom plate. The first-stage blades and the second-stage blades are arranged on the front side of the rotating disc, the third-stage blades are arranged on the rear side of the rotating disc, the first-stage blades and the second-stage blades are arranged at intervals, the first-stage blades are longer than the second-stage blades, the top ends of the first-stage blades are arranged on the outer edge of the rotating disc, and the tail ends of the second-stage blades are arranged on the edge of the connecting opening. The top ends of the third-stage blades are arranged on the outer edge of the rotating disc, the tail ends of the third-stage blades are arranged on the edge of the connecting opening, the pump cover is provided with a plurality of first transfer channels along the pump cover shell, the volute is axially provided with a plurality of second transfer channels, and the first transfer channels and the second transfer channels are in one-to-one correspondence and are in one-to-one connection.

Description

technical field [0001] The invention relates to the field of centrifugal pumps, in particular to a centrifugal pump for reducing gap leakage flow. Background technique [0002] A centrifugal pump is a pump that transports liquid by the centrifugal force generated when the impeller rotates. In order to reduce the volume and size of the centrifugal pump, the subsequent problem is that the centrifugal pump is small in size, resulting in the impeller at high speed, there is a tip clearance in the half-open and fully-open centrifugal pumps; due to the blade pressure surface The pressure is higher than the pressure on the suction surface, so that this part of the liquid flow bypasses the tip edge and enters the axial gap between the casing and the blade, forming a leakage flow at the tip gap of the blade, and finally returns to the impeller inlet. There is always a part of the liquid flow in the gap circulation, resulting in energy loss, this flow is called gap leakage flow, resu...

AI Technical Summary

Problems solved by technology

In order to reduce the volume and size of the centrifugal pump, the subsequent problem is that the centrifugal pump is small in size, resulting in the impeller at high speed, there is a tip clearance in the half-open and fully-open centrifugal pumps; due to the blade pressure surface The pressure is higher than the pressure on the suction surface, so that this part of the liquid flow bypasses the tip edge and enters the axial gap between the casing and the blade, forming a leakage flow at the tip gap of the blade, and finally returns to the impeller inlet. There is always a part of the liquid flow in the gap circulation, resulting in energy loss, this flow is called gap leakage flow, resulting in reduced hydraulic efficiency and axial force problems

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