CN-122014871-A - Prevent two flashboard flat gate valves of cavity superpressure explosion

CN122014871ACN 122014871 ACN122014871 ACN 122014871ACN-122014871-A

Abstract

The invention relates to the technical field of double-gate plate gate valves, and provides a double-gate plate gate valve capable of preventing explosion of a middle cavity overpressure aiming at the pain points that the sealing pair is seriously worn when the existing valve is opened and closed, the explosion is easily caused by the middle cavity overpressure and the applicability of the existing pressure relief scheme is poor. The invention is characterized in that an adjusting device capable of adjusting sealing specific pressure is arranged at the lower end of a valve rod, a flashboard component is provided with an elastic telescopic pull rod, the flashboard component adopts a pushing block with bevel transmission, the pushing block is matched with a telescopic cylinder sleeve structure, when the valve rod is closed, a left flashboard seals an inlet cavity first, a middle cavity residual medium is automatically emptied through an outlet cavity, and then a right flashboard seals the outlet cavity, and a pressure relief valve is not required to be additionally arranged. The invention effectively reduces the abrasion loss of the sealing pair, thoroughly avoids the risk of overpressure of the middle cavity, is suitable for the working conditions of high pressure, high temperature and extremely toxic/inflammable and explosive medium, and greatly improves the service life and the operation safety of the valve.

Inventors

Weng wanda
TENG CAIHONG
SU MIN
CHEN XIANXIAO
TIAN KAIYANG

Assignees

万能阀门有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (8)

1. The double-flashboard flat gate valve capable of preventing overpressure explosion of the middle cavity comprises a valve body, a valve cover, a valve rod and a driving device, wherein an inlet cavity, an outlet cavity, a flashboard assembly, a left valve seat and a right valve seat are arranged in the valve body; the flashboard assembly comprises a left flashboard and a right flashboard, wherein the left flashboard and the right flashboard are provided with a left cylinder and a right cylinder which are opposite, the left cylinder and the right cylinder are respectively and telescopically arranged at two ends of a cylinder sleeve, the cylinder sleeve is sequentially sleeved with a left pushing block, a right pushing block and a right pushing block, a vertical moving gap is formed between the left pushing block and the right pushing block, a left inclined surface which is matched with the left pushing block in a driving way is arranged between the left pushing block and the left pushing block, the left pushing block is jointed with the left flashboard, a right inclined surface which is matched with the right pushing block is arranged between the right pushing block and the left pushing block, the upper end of the left pushing block is connected with the lower end of a pull rod, the upper ends of the left pulling block and the right pulling block are respectively in transmission fit with the upper ends of the left pushing block, the upper ends of the right pulling block are in transmission fit with the lower ends of an adjusting device, the lower end of the left pushing block is connected with a lower valve rod, a lower positioning hole is formed in the bottom of a valve body corresponding to the lower valve rod, and a lower limiting structure of the left pushing block and the right pushing block is further arranged at the bottom of the valve body.
2. The dual-flashboard flat gate valve capable of preventing overpressure explosion of a middle cavity is characterized in that the adjusting device comprises an adjusting sleeve, a pull head, an adjusting block and a cross rod, the upper end of the pull sleeve is connected to the lower end of a valve rod, the adjusting block can be arranged in the pull sleeve in a vertically movable mode, the cross rod penetrates through the adjusting block, a vertical groove is formed in the corresponding pull sleeve, the adjusting sleeve is in threaded connection with the upper end of the pull sleeve, the adjusting sleeve forms the upper limit of the adjusting block, the upper end of the pull rod stretches into the pull sleeve, a spring is arranged between the pull rod and the adjusting block, the pull head is arranged at the lower end of the pull sleeve, the pull head forms the lower limit of the pull rod, and the lower end of the pull sleeve is in transmission fit with the upper end of the right pull head.
3. The double-flashboard flat gate valve capable of preventing the overpressure explosion of the middle cavity as set forth in claim 2, wherein the upper end of the pull rod is a T-shaped head, and the T-shaped head extends into and is limited in the pull sleeve.
4. The double-flashboard flat gate valve capable of preventing overpressure explosion of a middle cavity as set forth in claim 1, wherein the outer side of the left top block is provided with an anti-rotation groove, and the corresponding inner wall of the valve body is provided with an anti-rotation groove, and the anti-rotation groove is matched with the anti-rotation groove.
5. The double-flashboard flat gate valve capable of preventing overpressure explosion of a middle cavity as set forth in claim 1, wherein the driving device is arranged at the upper end of the valve cover through a bracket, a filler is arranged between the upper end of the valve cover and the valve rod, the filler is provided with a gland, and the gland and the bracket are jointly fixed at the upper end of the valve cover.
6. The double-gate plate gate valve capable of preventing overpressure explosion of a middle cavity as set forth in claim 1, wherein the left cylinder is integrally formed in the center of the inner side surface of the left gate plate, and the right cylinder is integrally formed in the center of the inner side surface of the right gate plate.
7. The double-gate plate gate valve capable of preventing overpressure explosion of a middle cavity as set forth in claim 1, wherein the left inclined plane and the right inclined plane are arranged opposite to each other and are both upper inclined planes.
8. The double-flashboard flat gate valve for preventing overpressure explosion of a middle cavity as set forth in claim 1, wherein the lower limit structures of the left push block and the right push block are respectively a lower left limit block and a lower right limit block, the lower left limit block is in limit fit with the left push block, and the lower right limit block is in limit fit with the right push block.

Description

Prevent two flashboard flat gate valves of cavity superpressure explosion Technical Field The invention relates to the technical field of valves, in particular to a double-flashboard flat gate valve capable of preventing overpressure explosion of a middle cavity, and aims to solve the technical problems that when an existing double-flashboard flat gate valve is opened and closed, a sealing pair is seriously worn, explosion is easily caused by overpressure of the middle cavity, and the applicability of an existing pressure relief scheme is poor. Background The double-flashboard flat gate valve is characterized in that two flashboard and two valve seats are combined into two sealing pairs in the valve body, so that the valve body can bear very large medium pressure, and the valve body has good sealing performance when being used for a high-pressure, high-temperature and high-flow pipeline, but has certain technical defects, and the valve body has the defects that in order to keep enough sealing specific pressure of a sealing surface, the sealing pairs between the flashboard and the valve seats are subjected to large friction force in the opening and closing process of the valve, so that the sealing pairs are easy to damage, meanwhile, when the valve is closed, a medium can remain in a middle cavity, the medium in the middle cavity can be influenced by external temperature, thermal expansion and cold contraction can be generated, and particularly under the high-temperature working conditions such as fire disaster, the medium in the middle cavity is expanded at high temperature, so that the valve is burst. Some existing double-flashboard flat gate valves can be provided with a pressure relief valve at a middle cavity, when medium in the middle cavity generates high pressure, the medium is discharged through the pressure relief valve, but the cost is increased, meanwhile, the medium with extremely toxic and strong corrosiveness cannot be directly discharged to the outside, and the scheme is completely inapplicable. In addition, the scheme that a part is free of a pressure relief valve realizes pressure relief of the middle cavity by optimizing the flashboard structure, but the problems of complex structure, inconvenient adjustment of sealing specific pressure, unstable pressure relief reliability and the like exist. Disclosure of Invention The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a double-flashboard flat gate valve for preventing overpressure explosion of a middle cavity. The invention aims to solve the technical problems, and adopts the following technical scheme that the double-flashboard flat gate valve capable of preventing the overpressure explosion of the middle cavity comprises a valve body, a valve cover, a valve rod and a driving device, wherein an inlet cavity, an outlet cavity, a flashboard assembly, a left valve seat and a right valve seat are arranged in the valve body; the flashboard assembly comprises a left flashboard and a right flashboard, wherein the left flashboard and the right flashboard are provided with a left cylinder and a right cylinder which are opposite, the left cylinder and the right cylinder are respectively and telescopically arranged at two ends of a cylinder sleeve, the cylinder sleeve is sequentially sleeved with a left pushing block, a right pushing block and a right pushing block, a vertical moving gap is formed between the left pushing block and the right pushing block, a left inclined surface which is matched with the left pushing block in a driving way is arranged between the left pushing block and the left pushing block, the left pushing block is jointed with the left flashboard, a right inclined surface which is matched with the right pushing block is arranged between the right pushing block and the left pushing block, the upper end of the left pushing block is connected with the lower end of a pull rod, the upper ends of the left pulling block and the right pulling block are respectively in transmission fit with the upper ends of the left pushing block, the upper ends of the right pulling block are in transmission fit with the lower ends of an adjusting device, the lower end of the left pushing block is connected with a lower valve rod, a lower positioning hole is formed in the bottom of a valve body corresponding to the lower valve rod, and a lower limiting structure of the left pushing block and the right pushing block is further arranged at the bottom of the valve body. Preferably, the adjusting device comprises an adjusting sleeve, a pull head, an adjusting block and a cross rod, wherein the upper end of the pull sleeve is connected to the lower end of the valve rod, the adjusting block can be arranged in the pull sleeve in a vertically moving manner, the cross rod is arranged on the adjusting block in a penetrating manner, a vertical groove is formed in the corresponding pull sleeve, the adjusting s