CN113280160B

CN113280160B - Detachable axial-flow check valve normally open structure

Info

Publication number: CN113280160B
Application number: CN202110409503.4A
Authority: CN
Inventors: 王秋林; 田峰; 刘其斌; 顾朝党; 尹春雨
Original assignee: SHANGHAI VALVE FACTORY CO Ltd
Current assignee: SHANGHAI VALVE FACTORY CO Ltd
Priority date: 2021-04-16
Filing date: 2021-04-16
Publication date: 2023-06-02
Anticipated expiration: 2041-04-16
Also published as: CN113280160A

Abstract

The invention discloses a detachable axial flow check valve normally open structure which comprises a valve clack, a fairing and a guide rod connected with the valve clack, wherein a spring installation boss is arranged at one end of the guide rod far away from the valve clack, a compression spring is installed on the spring installation boss, a shaft sleeve is sleeved at the outer side of one end of the guide rod close to the valve clack, the shaft sleeve limits the stroke of the compression spring, the shaft sleeve is fixedly clamped with the fairing, and a shaft sleeve gland preventing the shaft sleeve from rotating is arranged at the outer side of the shaft sleeve. The invention can maintain the valve to be normally open when the system is in a low-power operation condition, and can conveniently and quickly carry out on-line maintenance.

Description

Detachable axial-flow check valve normally open structure

Technical Field

The invention relates to a detachable axial flow check valve normally open structure used in the field of valves.

Background

The conventional axial flow check valve adopts a normally closed structure, when the valve is opened, working medium firstly needs to overcome the spring force and the friction force generated by the dead weight of the opening and closing member, so that the opening pressure difference of the valve is large, when the system of the valve is in a low-power operation working condition, the acting force of the working medium is slightly larger or even smaller than the spring force and the friction force generated by the dead weight of the opening and closing member, the axial flow check valve has insufficient opening height, and the valve can not be opened in severe cases. For a passive system which relies on the dead weight of a medium to drive the fluid circulation of the system, the normally closed valve is selected to be incapable of meeting the working requirement of the system, and even the valve can not be opened when the condition is serious, so that the system is in water loss accident.

In addition, in order to ensure the circulation capacity, the valve body of the conventional axial flow check valve is designed into a whole, if the valve is in welded connection with a pipeline, common faults such as abrasion, clearance inclusion and the like of a moving part of the valve cannot be maintained on line, the period required by cutting and maintaining the valve and the pipeline is long, the number of times of repeated welding with the pipeline is limited, the reliability verification after the welding of the valve and the pipeline is difficult, and the risk of irradiation influence of maintenance personnel is high. For valves in service in irradiation areas, conventional axial flow check valves have failed to meet service requirements in areas with irradiation, high risk, etc.

Disclosure of Invention

The invention aims to overcome the defects of the prior art, and provides a detachable axial flow check valve normally open structure which can maintain the normally open valve when a system is in a low-power operation working condition and can be conveniently and quickly maintained on line.

The technical scheme for achieving the purpose is as follows: a detachable axial flow check valve normally open structure comprises a valve clack, a fairing and a guide rod connected with the valve clack;

the one end that the valve clack was kept away from to the guide arm is equipped with the spring installation boss, installs compression spring on this spring installation boss, the one end outside that the guide arm is close to the valve clack has cup jointed the axle sleeve, and this axle sleeve is right compression spring's stroke is spacing, the axle sleeve with the radome fairing joint is fixed the axle sleeve outside is provided with the prevention the rotatory axle sleeve gland of axle sleeve.

Furthermore, the valve clack and the guide rod are in locking threaded connection through a pin shaft, and the fairing is spliced through a screw.

Further, a plurality of convex shoulders are arranged on the outer side of the shaft sleeve, and clamping grooves matched with the convex shoulders are formed in the fairing;

still further, the sleeve gland is provided with a waist-shaped hole matched with the shoulder, and the sleeve is prevented from rotating by the waist-shaped hole.

Further, a pressure relief hole is formed in the fairing, the position of the hole is the position of the end part of the guide rod when the valve clack is closed to 80% of the full stroke, and the guide rod passes through the pressure relief hole in the moving process.

Furthermore, the middle part of the valve body of the normally open structure of the axial flow check valve adopts a middle flange structure.

The detachable axial flow check valve normally open structure has small full-open flow resistance coefficient, and can still ensure the circulation capacity of the valve under the low-flow working condition, thereby ensuring that the fluid required by the system is sufficient when the system where the valve is positioned is under the low-power operation working condition; the valve body is not required to be cut, so that parts such as the valve clack, the valve rod and the like can be replaced conveniently and quickly, and online maintenance is realized; the impact load when the valve is closed can be effectively reduced, and the water hammer effect is reduced. The invention has simple structural design, simple installation and operation, effectively reduces the full-open flow resistance of the valve and improves the reliability of system operation under the low-flow working condition.

Drawings

FIG. 1 is a schematic diagram of a normally open structure of a removable axial flow check valve of the present invention;

FIG. 2 is a schematic illustration of a fairing of a normally open construction of a removable axial flow check valve in accordance with the present invention;

FIG. 3 is a cross-sectional view in the direction C-C of FIG. 2;

FIG. 4 is an axial view of a sleeve of a normally open construction of a removable axial flow check valve of the present invention;

fig. 5 is an axial view of a sleeve gland of a normally open structure of a removable axial flow check valve of the present invention.

Detailed Description

In order to better understand the technical solution of the present invention, the following detailed description is given by way of specific examples:

referring to fig. 1, the invention relates to a detachable axial flow check valve normally open structure, which comprises a valve clack 1, a fairing 2, a guide rod 3 connected with the valve clack, a compression spring 4, a shaft sleeve 5 and a shaft sleeve gland 6.

The valve clack 1 and the guide rod 3 are in locking threaded connection through a pin shaft, and the fairing 2 is spliced through a screw. One end of the guide rod 3, which is far away from the valve clack 1, is provided with a spring installation boss, a compression spring 4 is installed on the spring installation boss, the outer side of one end of the guide rod 3, which is close to the valve clack 1, is sleeved with a shaft sleeve 5, and the shaft sleeve 5 limits the stroke of the compression spring 3.

Referring to fig. 2 to 5, 3 convex shoulders 51 are provided on the outer side of the shaft sleeve 5, a clamping groove 21 matching with the convex shoulders 51 is provided on the inner side of the fairing 2, and the shaft sleeve 5 is axially fixed relative to the fairing 2 through the clamping groove 21. The sleeve gland 6 is provided with a waist-shaped hole 61 matched with the shoulder 51, the shoulder 51 is clamped through the waist-shaped hole 61, and the sleeve 5 is prevented from being separated from the fairing 2 due to circumferential rotation. The sleeve gland 6 is connected with the fairing 2 through a fastener.

The fairing 2 is provided with a pressure relief hole, the position of the hole is the position of the end part of the guide rod when the valve clack is closed to 80% of the full stroke, and the guide rod passes through the pressure relief hole in the movement process. In the initial stage of closing the valve, the pressure relief hole plays a role in pressure relief, and a piston effect for preventing the valve from closing is prevented from being formed on the side where the compression spring is located; when the boss at the tail end of the guide rod is plugged or passes through the pressure relief hole, a piston cavity is formed in front of the boss at the tail end of the guide rod, so that the closing speed of the valve clack is slowed down, the impact load between the valve clack and the valve body during large-flow closing can be reduced, and the water hammer effect is reduced.

The middle part of the valve body of the normally open structure of the axial flow check valve adopts a middle flange structure with a stud and a nut which are connected, so that the internal parts of the axial flow check valve can be detached from the flange holes when the internal parts are needed. Meanwhile, because the flange hole is larger, the valve has large operation space when in on-line inspection, and the condition of missed inspection caused by insufficient illumination of an unreachable area or a partial area when in endoscopic inspection through a small hole is avoided. The design completely avoids the problems of repeated cutting and welding of the valve and the pipeline. And the period required for on-line inspection and maintenance is greatly shortened. The valve cover of the axial flow check valve is matched with the valve body to manufacture a flow passage, so that the flow resistance coefficient of the medium flowing through the valve is kept consistent with that of the integral structure.

The invention relates to a specific installation and maintenance method of a normally open structure of a detachable axial flow check valve, which comprises the following steps:

1. and loading the spring installation boss end of the guide rod into the pressure relief hole of the fairing.

2. And then loading the compression spring, adopting the shaft sleeve to compress the spring, enabling the shoulder of the shaft sleeve to be matched with the groove on the fairing, pressing the shaft sleeve into the shaft sleeve until the shaft sleeve is completely attached to the fairing, and rotating the shaft sleeve for about 180 degrees, so that the shoulder is clamped with the clamping groove, and the shaft sleeve is completely fixed on the fairing.

3. And a shaft sleeve gland is arranged, so that a waist-shaped hole on the shaft sleeve gland is matched with a shaft sleeve shoulder to prevent the shaft sleeve from rotating circumferentially.

4. And finally, connecting the shaft sleeve gland and the fairing together by using a fastener.

5. Under normal working conditions, the spring force overcomes the friction force generated by the weight of the valve clack and the guide rod assembly, so that the valve is kept open; when the medium backflow working condition occurs, the medium force overcomes the spring force and the friction force generated by the weight of the valve clack and the guide rod component, so that the valve is closed; after the medium backflow working condition is finished, the valve clack and the guide rod assembly are restored to the valve opening position again under the action of spring force.

6. When the spring or the internal part is damaged, the middle flange is disassembled, the shaft sleeve gland screw is loosened, the shaft sleeve gland is taken out, then the valve clack is separated from the guide rod screw thread, and the valve clack is lifted out. And rotating the shaft sleeve to align the shaft sleeve convex shoulder with the groove on the fairing and then axially taking out the shaft sleeve. And finally, taking out the compression spring and the guide rod for maintenance or replacement. The convenient on-line maintenance mode can effectively prolong the service cycle of the valve.

It will be appreciated by persons skilled in the art that the above embodiments are provided for illustration only and not for limitation of the invention, and that variations and modifications of the above described embodiments are intended to fall within the scope of the claims of the invention as long as they fall within the true spirit of the invention.

Claims

1. The utility model provides a removable axial flow check valve normally open structure, includes valve clack (1), radome fairing (2) and guide arm (3) be connected with valve clack (1), its characterized in that: one end of the guide rod (3) far away from the valve clack (1) is provided with a spring installation boss, a compression spring (4) is installed on the spring installation boss, a shaft sleeve (5) is sleeved on the outer side of one end of the guide rod (3) close to the valve clack (1), a plurality of convex shoulders (51) are arranged on the outer side of the shaft sleeve (5), and clamping grooves (21) matched with the convex shoulders (51) are formed in the fairing (2); the shaft sleeve (5) limits the stroke of the compression spring (4), the shaft sleeve (5) is clamped with the clamping groove (21) by rotating the shaft sleeve (5), the shaft sleeve (5) is fixed on the fairing (2), and a shaft sleeve gland (6) for preventing the shaft sleeve (5) from rotating is arranged outside the shaft sleeve (5);

the shaft sleeve gland (6) is provided with a waist-shaped hole (61) matched with the shoulder (51), and the shaft sleeve (5) is prevented from rotating through the waist-shaped hole (61); the fairing (2) is provided with a pressure relief hole, the position of the pressure relief hole is the position of the end part of the guide rod (3) when the valve clack (1) is closed to 80% of the full stroke, and the guide rod (3) passes through the pressure relief hole in the moving process;

the valve clack (1) is in locking threaded connection with the guide rod (3) through a pin shaft, and the fairing (2) is spliced through a screw;

the middle part of the valve body adopts a middle flange structure with a stud and a nut which are connected, so that the internal part of the axial flow check valve can be detached from the flange hole when the internal part is needed;

the valve clack (1) is in locking threaded connection with the guide rod (3) through a pin shaft, and the fairing (2) is spliced through screws.