Balance structure of rotor for starting water feeding pump

Abstract

The invention discloses a balance structure of a rotor for starting a water feeding pump, which comprises a pump shaft, impellers sleeved on the pump shaft, a middle seal shaft sleeve, a rear seal shaft sleeve and a shaft sleeve nut. The impellers comprise nine stages, the nine stages of impellers comprise a first-stage impeller, a second-stage impeller, a third-stage impeller, a fourth-stage impeller and a fifth-stage impeller which are sequentially arranged from front to back in a low pressure area, and further comprises a sixth-stage impeller, a seven-stage impeller, an eighth-stage impeller and a ninth-stage impeller which are sequentially arranged from back to front in a high pressure area, inlets of the five stages of impellers of the low pressure area point to the driving end of a charging pump, and the four stages of impellers of the high pressure area are symmetrically arranged with the rear four stages of impellers in the low pressure area in back-to-back mode. Rear hubs of the nine stages of impellers have the same outer diameter, the diameter of an inlet of the first-stage impeller of the low pressure area is larger than that of inlets of the other eight stages of impellers, and the shapes and sizes of the other eight stages of impellers are the same. The middle seal shaft sleeve is sleeved between the fifth-stage impeller and the ninth-stage impeller, the rear seal shaft sleeve is arranged at the rear end of the sixth-stage impeller, the outer diameter of the rear seal shaft sleeve is larger than that of the rear hubs of the nine stages of impellers, a nut of the shaft sleeve is fixed at the rear end of the rear seal shaft sleeve.

Description

technical field [0001] The invention relates to a start-up feedwater pump for a nuclear power plant, in particular to a balance structure for a rotor of the start-up feedwater pump. Background technique [0002] The start-up feed water pump for nuclear power plants is used to supply water to the steam generator during the start-up and normal shutdown of the reactor, without using the water source of the auxiliary water supply system, and to facilitate the flushing of the secondary circuit during start-up. The existing start-up feed water pump is a horizontal multistage pump, and the existing multistage pumps mostly use balance discs or balance drums to balance the axial force of the rotor parts, so the structure of the rotor parts is complicated. Contents of the invention [0003] The purpose of the present invention is to overcome the disadvantages of the prior art and provide a balance structure for starting the rotor of the feed water pump, which can automatically balan...

AI Technical Summary

Problems solved by technology

The existing start-up feed water pump is a horizontal multi-stage pump, and the existing multi-stage pumps mostly use balance discs or balance drums to balance the axial force of the rotor parts, so the structure of the rotor parts is complicated

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