CN216894921U

CN216894921U - Boiler feed pump with transition type box body

Info

Publication number: CN216894921U
Application number: CN202220566517.7U
Authority: CN
Inventors: 付博; 张维学; 张爽
Original assignee: Shenyang Industrial Pump Factory Co ltd
Current assignee: Shenyang Industrial Pump Factory Co ltd
Priority date: 2022-03-16
Filing date: 2022-03-16
Publication date: 2022-07-05
Anticipated expiration: 2032-03-16

Abstract

A boiler feed pump with a transition box body is disclosed, the problem to be solved by the application is how to prolong the service life of a stepped shaft and reduce the abrasion of the stepped shaft, the technical scheme of the application is that a pump cover and an intake box body are respectively fixed at two ends of a cylinder body, a shaft end seal is arranged outside the pump cover and the intake box body, the shaft end seal is connected with the stepped shaft through a bearing, and a sealing ring is arranged on a flow passage of an impeller; transition box bodies are arranged between the front 6 groups of guide vanes and impellers and the rear six groups of guide vanes and impellers; the transition box body is arranged in the middle of the cylinder body, a plurality of inclined runners are arranged on the circumference of the transition box body, and adjacent inclined runners are arranged in a staggered mode; the pulling force of the shaft is reduced by half, and the stress condition and the service performance of the shaft are improved; the balance backwater water pressure is reduced, the efficiency is increased, and the reliable operation of the pump is reinforced.

Description

Boiler feed pump with transition type box body

Technical Field

The application relates to the technical field of feed pumps, in particular to a boiler feed pump with a transition type box body.

Background

The demand of the medium-high pressure multistage centrifugal pump in the process flow of various devices is increased and expanded continuously in the fields of medium petrochemistry, medium petroleum, power stations (including nuclear power stations), steel enterprises and the like, and the pump has the advantages of stable operation, low failure rate and simple and quick maintenance.

The multistage pump is formed by connecting a cylinder body, a middle section, a plurality of impeller guide vanes and a pump cover into a whole by using main bolts and nuts, so that the multistage pump has serious loss on a bearing and has high requirement on eliminating axial force on a rotor.

The existing multi-stage pump structure is that a balance drum (disc) is arranged at the position of a final-stage impeller to eliminate the axial force of a rotor, the structure can only eliminate a part of the axial force of the whole pump rotor, and the rest of the axial force needs to be eliminated through a thrust bearing, so that the load of the bearing can be increased, and the whole service life of the pump is shortened.

The technical problem that this application will solve is: the service life of the bearing is prolonged, and the abrasion of the bearing is reduced.

Disclosure of Invention

It is an object of the present application to provide a boiler feed pump with a transition box.

The purpose of the application is realized by the following steps: the pump body comprises a bearing body, a pump cover, a cylinder body, a transition box body, a sealing ring, a guide vane, an impeller and an inhalation box body; a pump cover and a suction box body are respectively fixed at two ends of the cylinder body, shaft end seals are arranged outside the pump cover and the suction box body and are connected with a bearing body through bearings, 12 groups of guide vanes and impellers are sequentially arranged on the bearing body, and a sealing ring is arranged on a flow passage of each impeller; transition box bodies are arranged between the front 6 groups of guide vanes and impellers and the rear six groups of guide vanes and impellers; the transition function body sets up at the barrel middle part, and the transition function body is cyclic annular, and the transition function body is gone up the circumference and is provided with a plurality of slant runners, and adjacent slant runner is crisscross setting.

The application has the advantages that:

the residual axial force is avoided, the bearing load of the bearing is increased, and the service life of the bearing is prolonged; the pulling force of the shaft is reduced by half, and the stress condition and the service performance of the shaft are improved; the mechanical seal stress is reduced, the service life is prolonged, the balance backwater water pressure is reduced, the efficiency is improved, and the reliable operation of the pump is reinforced.

Drawings

FIG. 1 is a schematic block diagram of the structure of the present application;

FIG. 2 is a schematic block diagram of the structure of a transition body of the present application;

fig. 3 is a cross-sectional view of fig. 2.

Detailed Description

Referring to fig. 1, the pump body comprises a bearing body 1, a pump cover 2, a cylinder 3, a transition box body 4, a sealing ring 5, a guide vane 6, an impeller 7 and an intake box body 8; a pump cover and a suction box body are respectively fixed at two ends of the cylinder body, shaft end seals are arranged outside the pump cover and the suction box body and are connected with a bearing body through bearings, 12 groups of guide vanes and impellers are sequentially arranged on the bearing body, and a sealing ring is arranged on a flow passage of each impeller; transition box bodies are arranged between the front 6 groups of guide vanes and impellers and the rear six groups of guide vanes and impellers; the transition function body sets up at the barrel middle part, and the transition function body is cyclic annular, and the transition function body is gone up the circumference and is provided with a plurality of slant runners 11, and adjacent slant runner is crisscross setting.

The impellers of 1 to 6 stages of the rotor are placed on the same side, the impellers of 7 to 12 stages are symmetrically arranged through the staggered design of the transition sections, the purpose of symmetrical arrangement of the impellers is achieved, the generated axial force is the same because the differential pressure value of each stage of the impeller is fixed during operation, and the symmetrically arranged impellers can save a balancing drum (disc) with an original structure and achieve the purpose of mutually symmetrically balancing the axial force. The axial force that bears like this is impartial, can not produce the load of too big axial force to the bearing, and the symmetry of log progression is two simultaneously, and the pulling force of axle reduces half, and the mechanical seal atress reduces (instantaneous intracavity pressure reduces), and balanced return water pressure reduces, increases efficiency, and this technique promotes the efficiency of pump, the reduction of maintenance rate, and sealed life's increase has played very important effect to the whole life of pump.

The design method of the symmetrically arranged impellers is adopted, so that the axial forces are balanced, excessive residual axial force is not generated, the service life of the bearing is prolonged, the fault rate of the pump is reduced, the overhaul period of the pump is prolonged, and the frequency of replacing parts is reduced.

During operation, a medium enters the water inlet impeller diversion flow channel 10 through the transition box body 4 through the accelerated pressurization of the 1-6-stage impeller, and the medium enters the water outlet impeller to the six flow channels 9 again through the accelerated pressurization of the rear 6-stage impeller and then is output.

Claims

1. A boiler feed pump with a transition box, comprising: the pump body, characterized by: the pump body comprises a stepped shaft, a pump cover, a cylinder body, a transition box body, a sealing ring, a guide vane, an impeller and an suction box body; a pump cover and a suction box body are respectively fixed at two ends of the cylinder body, shaft end seals are arranged outside the pump cover and the suction box body and are connected with a stepped shaft through a bearing, 12 groups of guide vanes and impellers are sequentially arranged on the stepped shaft, and a sealing ring is arranged on a flow passage of the impeller; transition box bodies are arranged between the front 6 groups of guide vanes and impellers and the rear six groups of guide vanes and impellers; the transition function body sets up at the barrel middle part, and the transition function body is cyclic annular, and the transition function body is gone up the circumference and is provided with a plurality of slant runners, and adjacent slant runner is crisscross setting.