WO2019019127A1

WO2019019127A1 - Combined low-torque flat gate valve

Info

Publication number: WO2019019127A1
Application number: PCT/CN2017/094810
Authority: WO
Inventors: 周传本; 黄国成
Original assignee: 江苏政轩石油机械股份有限公司
Priority date: 2017-07-28
Filing date: 2017-07-28
Publication date: 2019-01-31

Abstract

A combined low-torque flat gate valve, comprising a valve body (100), a valve cavity (200), first valve seats (300) and a first valve plate (400); the first valve seats (300) are provided in the valve cavity (200) and connect medium channels (101) located at two ends thereof, and divide the valve cavity (200) into an upper cavity (201), a middle cavity (202) and a lower cavity (203) in order. Said valve further comprises: a second valve plate (500), which is provided in the first valve plate (400), the first valve plate (400) being provided with flow guide channels (401), the flow guide channels (401) being in communication with the medium channels (101); and second valve seats (600), which connect the flow guide channels (401) located at two ends of the second valve seat. By providing the two second valve seats (600) and the second valve plate (500) in the interior of the first valve plate (400), a small sealing pair having a low opening torque is formed, such that the flow guide channels (401) can be opened under the condition of full-pressure, reducing the pressure difference between two sides of the first valve plate (400) and then driving the first valve plate (400) to move so as to fully open the large-diameter gate valve, solving the traditional problem that a flat gate valve, which has a huge diameter, in an oil and gas pipeline cannot be operated by a single person.

Description

Composite low torque slab gate valve

Technical field

The invention relates to the technical field of slab gate valves, in particular to a composite low torque slab gate valve used in the petroleum industry.

Background technique

The valve is a control component in the fluid delivery system, with functions such as cut-off, regulation, diversion, anti-backflow, pressure regulation, split or overflow relief; valves for fluid control systems, from the simplest shut-off valves to extremely complex The various valves used in the automatic control system are quite diverse in variety and specifications. The seat of the slab gate valve is tightly attached to the ram under the action of the spring preload and the pressure difference caused by the medium pressure difference to ensure the seal. The upper and lower valve seats are always close to the ram, causing the friction between the ram and the valve seat to be very large when the valve is opened. The torque is very heavy. Only the hand wheel diameter or actuator specifications are increased to solve the problem. Moreover, during the frequent use of this structure, the sealing ring is severely worn due to the opening pressure, and the valve seal is invalid.

At present, the slab gate valve technology has been developed and the use effect has been recognized. The slab gate valves used at home and abroad are both a ram and two valve seats distributed on both sides of the ram. Through the control of the ram, the full Open or fully closed, however, the gate valve is controlled by a single block. The torque is usually very large, the internal structure is complicated, the parts are many, and the sealing effect at the time of full closing is not optimistic. Under normal circumstances, the torque of the small-diameter low-pressure valve is not too large. Under normal circumstances, the movement of the gate can be made by the rotation of the hand wheel to realize the opening and closing of the gate valve. However, the manual opening torque of the large-diameter high-pressure valve is very large, and the movement of the ram is difficult to realize only by the rotation of the hand wheel, and with the progress of the pipeline technology, the pressure of the pipeline design is getting higher and higher, and the pipeline diameter is getting larger and larger. Because the slab gate valve is in the form of a floating valve seat, under the action of the medium pressure, the ram plate is close to the sealing surface of the downstream valve seat. The operating force of the ram under the full pressure difference is the medium positive pressure multiplied by the sealing surface friction coefficient, although the sealing surface is selected. Polytetrafluoroethylene with a low coefficient of friction (coefficient of friction is 0.05 to 0.1), but the valve operation force is still large, especially in the case of large diameter and high pressure, for example, the pressure of the oil and gas pipeline exceeds 16 MPa, and the diameter exceeds 1000mm, so the valve operating force increases rapidly, the valve operating device model size is large, and even has to use the deceleration booster device, the cost is higher, and also the valve opening and closing time is extended. Even if there is a ball screw pair used in a large-diameter high-pressure valve, the torque of the valve is greatly reduced, but the opening torque is still very large, generally reaching 500-600 N/m, and normally one or two people cannot open.

Summary of the invention

The purpose of this section is to summarize some aspects of the embodiments of the invention and to briefly describe some preferred embodiments. The simplifications or omissions may be made in this section as well as in the description of the invention and the invention, and the scope of the invention is not to be construed as limiting the scope of the invention.

The present invention has been made in view of the problems of the prior art composite low torque slab gate valve described above.

Therefore, the object of the present invention is to provide a composite low-torque slab gate valve, which greatly reduces the manufacturing cost and greatly reduces the labor intensity of the operator and improves the production efficiency.

In order to solve the above technical problem, the present invention provides the following technical solution: a composite low-torque slab gate valve including a valve body, a valve chamber and a first valve seat, wherein the valve body is provided with a medium passage for supplying medium in the left-right direction And a valve chamber in the up and down direction, the first valve seat is disposed in the valve cavity and communicates with the medium passage at both ends thereof, and the valve chamber is sequentially divided into an upper chamber, a middle chamber and a lower chamber, And the middle cavity is in communication with the medium passage, and further comprising: a first valve plate partially inserted into the first valve seat to cut off or communicate with the medium passage; and a second valve plate disposed at the The first valve plate includes a second intercepting end and a second transparent end, which are capable of cutting or conducting a flow guiding channel disposed in the left and right direction of the first valve plate, the guiding channel and the The medium passages are in communication; and the second valve seat communicates with the flow guiding passages at both ends thereof, and the second valve plate is inserted into the second valve seat to cut off or conduct the flow guiding passage.

A preferred embodiment of the composite low torque slab gate valve of the present invention, wherein: the first valve plate further includes a first cut end and a first through end, the first cut end being a solid portion, a sliding groove is disposed on the upper and lower sides, the second valve plate is slid in the sliding groove, and the flow guiding channel is cut off, the first transparent end is a transparent portion, and the medium passage can be Corresponding connection.

A preferred embodiment of the composite low-torque slab gate valve of the present invention, wherein: the second valve plate has the same structure as the first valve plate, and the second truncated end is a solid portion, a truncation The flow guiding channel is described, and the second transparent end is a transparent portion, and can communicate with the guiding channel.

A preferred embodiment of the composite low-torque slab gate valve according to the present invention, further comprising: a lifting member on which a finite protrusion is disposed, and the lifting member is divided into an upper end and a lower end by the limiting protrusion, The lower end is connected to the second valve plate, the inner diameter of the lower end is smaller than the inner diameter of the upper end, and a certain gap is formed between the lower end and the sliding groove.

As a preferred embodiment of the composite low-torque slab gate valve of the present invention, the first intercepting end further includes a limiting block and a contact member, and the limiting block covers the top end of the sliding slot. And The top end of the first valve plate is connected, and the abutting member is disposed at a bottom end of the gap and is connected to a top end of the second valve plate.

As a preferred embodiment of the composite low torque slab gate valve of the present invention, the method further includes a valve cover that is capped at the top end of the valve chamber and connected to the valve body.

A preferred embodiment of the composite low-torque slab gate valve of the present invention, wherein: the bonnet is further provided with a finite position port, and the limiting port can be limited with the limiting protrusion, and the The lifting piece continues to rise.

As a preferred embodiment of the composite low torque slab gate valve of the present invention, the length of the sliding groove is equal to the sum of the lengths of the lower end and the second valve plate.

A preferred embodiment of the composite low-torque slab gate valve according to the present invention, wherein the first permeable end is in communication with the medium passage when the limiting port is in contact with the limiting protrusion .

A preferred embodiment of the composite low-torque slab gate valve of the present invention, wherein: when the limiting block interferes with the abutting member, the guiding channel and the transparent portion of the second valve plate Corresponding connection.

The invention has the beneficial effects that the composite low-torque slab gate valve provided by the invention has two second valve seats and a second valve plate built in the first valve plate to form a small sealing pair with low opening torque. The flow guiding channel can be opened under full pressure condition, the pressure difference between the two sides of the first valve plate is reduced, and then the movement of the first valve plate is driven to realize the full opening of the large-diameter gate valve, and the large-diameter slab gate valve in the oil and gas pipeline can not be solved. The problem of single operation is not only simple and easy, reduces costs, greatly reduces the labor intensity of the operator, and greatly shortens the time for opening the valve and improves production efficiency.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the description of the embodiments will be briefly described below. It is obvious that the drawings in the following description are only some embodiments of the present invention, Those skilled in the art can also obtain other drawings based on these drawings without paying any inventive labor. among them:

1 is a schematic view showing the overall structure of a composite low-torque slab gate valve according to a first aspect of the present invention;

2 is a cross-sectional structural view showing the first low-torque slab gate valve of the first embodiment of the present invention in a state in which the valve is completely closed;

3 is a schematic view showing the overall structure of a second valve plate in the composite low-torque slab gate valve according to the first aspect of the present invention;

Figure 4 is a partial enlarged view of Figure 3 of the present invention;

5 is a schematic view showing the overall structure of a first valve plate in a composite low-torque slab gate valve according to a second embodiment of the present invention, wherein the second valve plate is removed;

6 is a schematic view showing the overall structure of a lifting member in a composite low-torque slab gate valve according to a third aspect of the present invention;

7 is a partially enlarged schematic structural view of a third type of composite low torque slab gate valve according to the present invention;

8 is a schematic structural view of the composite low-torque slab gate valve in the composite low-torque slab gate valve in conflict with the abutting member;

9 is a schematic structural view of a composite low-torque slab gate valve in a composite low-torque slab gate valve in contact with a limit protrusion;

FIG. 10 is a structural schematic view of the composite low-torque slab gate valve of the present invention in a closing process after the valve is fully opened.

Detailed ways

The above described objects, features and advantages of the present invention will become more apparent from the aspects of the appended claims.

In the following description, numerous specific details are set forth in order to provide a full understanding of the present invention, but the invention may be practiced in other ways than those described herein, and those skilled in the art can do without departing from the scope of the invention. The invention is not limited by the specific embodiments disclosed below.

In addition, "an embodiment" or "an embodiment" as used herein refers to a particular feature, structure, or characteristic that can be included in at least one implementation of the invention. The appearances of the "in one embodiment", "a" or "an"

Secondly, the present invention will be described in detail in conjunction with the accompanying drawings. When the embodiments of the present invention are described in detail, for the convenience of description, the sectional view of the structure of the device will not be partially enlarged according to the general proportion, and the schematic diagram is only an example, and should not be used here. Limit the scope of protection of the invention. In addition, the actual three-dimensional dimensions of length, width and depth should be included in the actual production.

1 to 3 are schematic views showing the overall structure of the composite low-torque slab gate valve in the fully closed state of the valve according to the first embodiment of the present invention, in order to realize the full-pressure opening operation of the single-plate gate valve, and simple Easy to do, greatly reducing the labor intensity of the operator, in this embodiment the composite low The torque slab gate valve includes a valve body 100, a valve chamber 200, a first valve seat 300, a first valve plate 400, a second valve plate 500, and a second valve seat 600. Specifically, the valve body 100 is internally provided with a left-right direction. The medium passage 101 through which the medium flows and the valve chamber 200 in the up and down direction, and the medium passage 101 communicates with the valve chamber 200 in the up and down direction in the valve body 100, that is, the valve chamber 200 is inserted into the medium passage 101 to divide it into an upstream medium passage. And a downstream medium passage; and the first valve seat 300 is disposed in the valve chamber 200 and communicates with the medium passages 101 at both ends thereof, that is, the first valve seat 300 connects the upstream medium passages at both ends and the downstream medium passage, where the first valve The seat 300 is a detachable surface part of the valve for supporting the fully closed position of the valve core and forming a sealing pair. The diameter of the valve seat is the maximum diameter of the valve, and the valve seat is widely used, such as various rubber, plastic or metal. The material can be used as a valve seat material; the first valve seat 300 sequentially divides the valve chamber 200 into an upper chamber 201, a middle chamber 202 and a lower chamber 203, wherein the middle chamber 202 communicates with the medium passage 101, and the diameter of the middle chamber 202 With media channel 101 The size of the diameter is matched, the medium can enter the middle cavity 202 through the upstream medium passage and then enter the downstream medium passage to complete the medium transportation; the first valve plate 400 is partially inserted into the first valve seat 300 to cut the medium passage 101, and the first valve plate The two ends of the 400 can move against the first valve seat 300 in the valve chamber 200 to cut off the medium. When the first valve plate 400 moves up to the top end of the upper chamber 201, the upward movement cannot be continued, and the valve is in an open state, and When the first valve plate 400 moves downward to the bottom end of the lower chamber 203, the valve is in a closed state. As shown in FIG. 1 , when the first valve plate 400 moves to the lower end of the valve chamber 200, the valve plate is two. The pressure difference of the side medium gradually increases, and vice versa, the pressure difference between the two sides of the valve plate decreases. Of course, in the embodiment, preferably, an elastic member is disposed between the two ends of the first valve seat 300 and the valve body 100, and the valve seat is pressed against the first valve plate 400 by the elastic member to enhance the sealing performance. Further, in order to realize the simple opening of the full pressure in the closed state of the first valve plate 400 and reduce the strength of the manual labor, the second valve plate 500 and the second valve seat 600 are further provided in this embodiment. Specifically, the second valve The plate 500 is disposed in the first valve plate 400, and the first valve plate 400 is further disposed with a flow guiding channel 401 disposed in the left-right direction. The guiding channel 401 is located in the middle cavity 202 and communicates with the medium channel 101. The two valve plate 500 moves up and down in the first valve plate 400, and can cut or turn on the flow guiding passage 401 in the first valve plate 400. When the first valve plate 400 moves downward to the bottom end of the lower chamber 203, the first A valve plate 400 blocks the medium to close the valve. At this time, both ends of the first valve plate 400 are in a full pressure state, and the second valve plate 500 in the first valve plate 400 is moved to facilitate the manual operation for pressure relief. The flow channel 401 communicates with the medium channel 101, and the medium enters the flow channel 401 from the upstream medium channel and then flows into the downstream medium channel. Therefore, the pressure difference between the two ends of the first valve plate 400 is reduced, and when the value difference between the two ends is balanced, The pressure difference between the two sides of the valve is very small, so it is closed Torque is small, single operation It is also relatively easy. Of course, the second valve seat 600 is similar to the first valve seat 300 for connecting the two end passages, and the second valve seat 600 is disposed on both sides of the second valve plate 500, and the two functions cooperate to realize the flow guiding passage 401. Turn it on and off. Also in this embodiment, preferably, an elastic member is disposed between the two ends of the second valve seat 600 and the second valve plate 500, and the valve seat is pressed against the second valve plate 500 by the elastic member to enhance the sealing performance. .

FIG. 5 is a schematic view showing the overall structure of a composite low-torque slab gate valve according to a second embodiment of the present invention in an open state, in order to realize a composite between the second valve plate 500 and the first valve plate 400. Referring to FIGS. 1 to 4, in the present embodiment, the difference from the first embodiment is that the first valve plate 400 further includes a first cut end 402 and a first through end 403. Specifically, the The composite low-torque slab gate valve includes a valve body 100, a valve chamber 200, a first valve seat 300, a first valve plate 400, a second valve plate 500, and a second valve seat 600. The valve body 100 is internally provided with a left-right direction. The medium passage 101 through which the medium flows and the valve chamber 200 in the up and down direction, and the medium passage 101 communicates with the valve chamber 200 in the up and down direction in the valve body 100, that is, the valve chamber 200 is inserted into the medium passage 101 to divide it into an upstream medium passage. And a downstream medium passage; and the first valve seat 300 is disposed in the valve chamber 200 and communicates with the medium passages 101 at both ends thereof, that is, the first valve seat 300 connects the upstream medium passages at both ends and the downstream medium passage, where the first valve The seat 300 is a detachable surface part of the valve. The support valve core is fully closed and constitutes a sealing pair. Generally, the diameter of the valve seat is the maximum diameter of the valve, and the valve seat material is very wide. For example, various rubber, plastic or metal materials can be used as the valve seat material; The valve seat 300 sequentially divides the valve chamber 200 into an upper chamber 201, a middle chamber 202 and a lower chamber 203, wherein the middle chamber 202 communicates with the medium passage 101, and the diameter of the middle chamber 202 coincides with the diameter of the medium passage 101, and the medium can After entering the middle cavity 202 through the upstream medium passage, the medium is transported into the downstream medium passage, and the first valve plate 400 is partially inserted into the first valve seat 300 to cut the medium passage 101, and the first valve plate 400 can interfere with the first end. The valve seat 300 moves within the valve chamber 200 to intercept the medium. When the first valve plate 400 moves up to the top end of the upper chamber 201, the upward movement cannot be continued, at which time the valve is in the open state, and when the first valve plate 400 moves downward to the bottom end of the lower chamber 203, the valve is closed. In the state shown in FIG. 1 , when the first valve plate 400 moves to the lower end of the valve chamber 200, the pressure difference between the two sides of the valve plate gradually increases, and vice versa, the pressure difference between the two sides of the valve plate decreases. Of course, in the embodiment, preferably, an elastic member is disposed between the two ends of the first valve seat 300 and the valve body 100, and the valve seat is pressed against the first valve plate 400 by the elastic member to enhance the sealing performance. Further, in order to realize the simple opening of the full pressure in the closed state of the first valve plate 400 and reduce the labor intensity, the second valve plate 500 and the second valve seat 600 are further provided. Specifically, the second valve The plate 500 is disposed in the first valve plate 400, and the first valve plate 400 is further disposed with a flow guiding channel 401 disposed in the left-right direction. The guiding channel 401 is located in the middle cavity 202 and communicates with the medium channel 101. The two valve plate 500 moves up and down within the first valve plate 400 to cut or turn on the flow guiding passage 401 in the first valve plate 400. In the present embodiment, the first valve plate 400 herein further includes a first cut end 402 and a first through end 403, wherein the first cut end 402 is a solid portion on which the sliding groove 402a is disposed in the up and down direction. The second valve plate 500 slides in the sliding groove 402a to cut off the flow guiding passage 401. The first transparent end 403 is a transparent portion and can communicate with the medium passage 101. The second valve plate 500 and the first valve plate The 400 has the same structure, and the cut-off portion is a solid body, and includes a second cut-off end 501 and a second pass-through end 502, which are capable of cutting or conducting the flow guiding passage 401 disposed in the left-right direction in the first valve plate 400, wherein The second truncated end 501 is a solid portion, the flow guiding channel 401 is cut off, and the second transparent end 502 is a transparent portion, and can communicate with the guiding channel 401. The transparent portion can communicate with the guiding channel 401. When the first valve plate 400 moves up to the top end of the upper chamber 201, the upward movement cannot be continued, at which time the first through end 403 is in complete communication with the medium passage 101, the valve is in a fully open state; and when the first valve plate 400 is When moving downward to the bottom end of the lower chamber 203, the first cut end 402 of the first valve plate 400 is just in the middle chamber 202, and the medium is blocked to bring the valve into a closed state, at which time both ends of the first valve plate 400 are at In the full pressure state, in order to facilitate the manual operation, the second valve plate 500 in the first valve plate 400 is moved to the flow passage 101 to communicate with the medium passage 101, that is, the second valve plate 500 moves in the sliding groove 402a, and the movement occurs. The state includes that the second valve plate 500 is a solid cut-off portion corresponding to the flow guiding channel 401, blocking the medium passage; and the second valve plate 500 has a transparent portion corresponding to the communication guide channel 401, and the medium is provided by the upstream medium passage. After entering the flow guiding channel 401, it flows into the downstream medium passage, so the pressure difference between the two ends of the first valve plate 400 is lowered. When the pressure difference between the two ends is balanced, since the pressure difference between the two sides of the valve is small, the torque is very close when the valve is closed. Small, single-player operations are relatively easy. Of course, the second valve seat 600 is similar to the first valve seat 300 for connecting the two end passages, and the second valve seat 600 is disposed on both sides of the second valve plate 500, and the two functions cooperate to realize the flow guiding passage 401. Turn it on and off. Also in this embodiment, preferably, an elastic member is disposed between the two ends of the second valve seat 600 and the second valve plate 500, and the valve seat is pressed against the second valve plate 500 by the elastic member to enhance the sealing performance. .

6 to 7 are schematic views showing the overall structure of the composite low-torque slab gate valve according to the third embodiment of the present invention, in order to realize the relationship between the second valve plate 500 and the first valve plate 400. The movement of the second valve plate 500 in the up-and-down direction in the first valve plate 400 in the composite structure and the up-and-down movement of the first valve plate 400 in the valve chamber 200 are different from the second embodiment in this embodiment. It The composite low-torque slab gate valve further includes a lifting member 700, specifically, the valve body 100, the valve chamber 200, the first valve seat 300, the first valve plate 400, the second valve plate 500, and the second valve. The seat 600 is provided with a medium passage 101 through which the medium flows in the left-right direction and a valve chamber 200 in the up-and-down direction, and the medium passage 101 communicates with the valve chamber 200 in the up-and-down direction in the valve body 100, that is, the valve The cavity 200 is inserted into the medium passage 101 to divide it into an upstream medium passage and a downstream medium passage; and the first valve seat 300 is disposed in the valve chamber 200 and communicates with the medium passage 101 at both ends thereof, that is, the first valve seat 300 is connected at both ends An upstream medium passage and a downstream medium passage, wherein the first valve seat 300 is a detachable surface part in the valve for supporting the full closed position of the valve core and forming a sealing pair, wherein the valve seat diameter is the maximum circulation diameter of the valve, and The valve seat material is very wide. For example, various rubber, plastic or metal materials can be used as the valve seat material; the first valve seat 300 sequentially divides the valve chamber 200 into an upper chamber 201, a middle chamber 202 and a lower chamber 203, wherein the middle chamber 202 and media channel 1 01 is connected, and the diameter of the middle cavity 202 coincides with the diameter of the medium passage 101. The medium can enter the middle cavity 202 through the upstream medium passage and then enter the downstream medium passage to complete the medium transportation; the first valve plate 400 is partially inserted into the first The medium passage 101 is cut in the valve seat 300, and both ends of the first valve plate 400 are movable against the first valve seat 300 to move within the valve chamber 200, thereby cutting the medium. When the first valve plate 400 moves up to the top end of the upper chamber 201, the upward movement cannot be continued, at which time the valve is in the open state, and when the first valve plate 400 moves downward to the bottom end of the lower chamber 203, the valve is closed. In the state shown in FIG. 1 , when the first valve plate 400 moves to the lower end of the valve chamber 200, the pressure difference between the two sides of the valve plate gradually increases, and vice versa, the pressure difference between the two sides of the valve plate decreases. Of course, in the embodiment, preferably, an elastic member is disposed between the two ends of the first valve seat 300 and the valve body 100, and the valve seat is pressed against the first valve plate 400 by the elastic member to enhance the sealing performance. Further, in order to realize the simple opening of the full pressure in the closed state of the first valve plate 400 and reduce the strength of the manual labor, the second valve plate 500 and the second valve seat 600 are further provided in this embodiment. Specifically, the second valve The plate 500 is disposed in the first valve plate 400, and the first valve plate 400 is further disposed with a flow guiding channel 401 disposed in the left-right direction. The guiding channel 401 is located in the middle cavity 202 and communicates with the medium channel 101. The two valve plate 500 moves up and down within the first valve plate 400 to cut or turn on the flow guiding passage 401 in the first valve plate 400. In the present embodiment, the first valve plate 400 herein further includes a first cut end 402 and a first through end 403, wherein the first cut end 402 is a solid portion on which the sliding groove 402a is disposed in the up and down direction. The second valve plate 500 slides in the sliding groove 402a to cut off the flow guiding passage 401. The first transparent end 403 is a transparent portion and can communicate with the medium passage 101. The second valve plate 500 and the first valve plate 400 has the same structure, and its truncated portion is an entity, including a second truncated end 501 and a second transparent end 502, two The flow guiding channel 401 disposed in the left and right direction of the first valve plate 400 can be cut off or turned on, wherein the second cutting end 501 is a solid portion, the flow guiding channel 401 is cut off, and the second transparent end 502 is a transparent portion. It can communicate with the flow guiding channel 401, and the transparent portion can communicate with the flow guiding channel 401. When the first valve plate 400 moves up to the top end of the upper chamber 201, the upward movement cannot be continued, at which time the first through end 403 is in complete communication with the medium passage 101, the valve is in a fully open state; and when the first valve plate 400 is When moving downward to the bottom end of the lower chamber 203, the first cut end 402 of the first valve plate 400 is just in the middle chamber 202, and the medium is blocked to bring the valve into a closed state, at which time both ends of the first valve plate 400 are at In the full pressure state, in order to facilitate the manual operation, the second valve plate 500 in the first valve plate 400 is moved to the flow passage 101 to communicate with the medium passage 101, that is, the second valve plate 500 moves in the sliding groove 402a, referring to FIG. ～10, wherein the second valve plate 500 is moved in the sliding groove 402a in the embodiment to provide a lifting member 700 and a top end of the second valve plate 500. Preferably, the upper end of the lifting member 700 Part of the thread is provided, which cooperates with an externally disposed nut to form a structure of a rolling screw. The ball screw is an ideal product for converting a rotary motion into a linear motion or converting a linear motion into a rotary motion, which is through an outer end. Hand wheel Transfer screw drive nut screw moves in the vertical direction, so as to drive the bottom of the second valve plate 500 moves in the vertical direction, greatly reduce the friction, reducing the torque handwheel. Further, a lifting protrusion 700 is further disposed on the lifting member 700. The lifting member 700 is divided into an upper end 701 and a lower end 702 by the limiting protrusion 701, wherein the lower end 702 is connected to the second valve plate 500, and the inner diameter of the lower end 702 is smaller than The inner diameter of the upper end 701 is preferably a one-piece structure in the present embodiment. The upper end 701 and the lower end 702 are preferably arranged in a separate manner, and are connected by the limiting protrusions 701. Further, the second valve plate 500 is sized to match the sliding groove 402a, and the lower end 702 is smaller in diameter than the inner diameter of the sliding groove 402a, so the lower end 702 is located in the sliding groove 402a, and a certain gap S is formed therebetween, and the top end of the sliding groove 402a is formed. The limiting block 402b is configured to cover the sliding slot 402a, and the lifting member 700 is connected to the second valve plate 500 through the limiting block 402b. Of course, in this embodiment, in order to facilitate the disassembly, installation and maintenance of the lifting member 700, the limiting block is provided. 402b is connected to the top end of the first valve plate 400, and the two are separated structures. Of course, it is not difficult to find that the two can also be an integrated structure; and the gap S is also disposed to interfere with the limiting block 402b. The resisting member 402c is disposed at the bottom end of the gap S and is connected to the top end of the second valve plate 500. Similarly, the abutting member 402c and the second valve plate 500 are separated or integrated. And the length of the sliding groove 402a is equal to the sum of the lengths of the lower end 702 and the second valve plate 500. The structure is set such that the state in the sliding groove 402a includes when the second valve plate 500 moves to the sliding The second valve when the bottom end of the groove 402a 500 is a truncated portion of the entity Correspondingly sealing to the flow guiding channel 401, blocking the medium passage, continuing to rotate the hand wheel to raise the lifting member 700, thereby causing the second valve plate 500 to rise, and the cut portion of the second valve plate 500 gradually leaves the guiding passage 401, and The transparent portion gradually enters and is in communication with the flow guiding channel 401. When the transparent portion of the second valve plate 500 completely corresponds to the communication guiding channel 401, the limiting block 402b and the abutting member 402c are in contact with each other, and the guiding channel 401 is The transparent portion of the second valve plate 500 is completely correspondingly communicated. At this time, the medium enters the flow guiding channel 401 from the upstream medium passage and then flows into the downstream medium passage. Therefore, the pressure difference between the two ends of the first valve plate 400 is reduced, and the ends of the first valve plate 400 are lowered. When the value differential pressure is balanced, the hand wheel is continuously rotated, and the lifting member 700 continues to rise. However, since the limiting block 402b is in conflict with the abutting member 402c, the limiting block 402b is fixedly connected to the top end of the first valve plate 400. The limiting block 402b has a tendency to move upward due to the upward force, so that the first valve plate 400 is moved upward; and in this embodiment, a valve cover 800 is further included, and the valve cover 800 covers the top of the valve chamber 200. And The body 100 is connected, and the same valve cover 800 and the valve body 100 can be either an integral type or a separate structure. Further, the valve cover 800 is further provided with a limited position port 801, which can be restrained from the limit protrusion 701. When the limiting port 801 is in contact with the limiting protrusion 701, the first through end 403 is completely in communication with the medium channel 101, and the valve is in a fully open state. Since the pressure difference between the two sides of the valve is small, the torque is small when closing and opening, and the single operation is relatively easy. Of course, the second valve seat 600 is similar to the first valve seat 300 for connecting the two end passages, and the second valve seat 600 is disposed on both sides of the second valve plate 500, and the two functions cooperate to realize the flow guiding passage 401. Turn it on and off. Also in this embodiment, preferably, an elastic member is disposed between the two ends of the second valve seat 600 and the second valve plate 500, and the valve seat is pressed against the second valve plate 500 by the elastic member to enhance the sealing performance. . If the valve needs to be closed, since the pressure difference between the two sides of the valve is small, contrary to the steering of the hand wheel when opening, the lifting member 700 is lowered, and since there is no medium pressure difference on both sides of the second valve plate 500, the second valve plate is first driven. After the 500 is lowered, the second valve plate 500 is no longer lowered by the bottom end of the sliding groove 402a, so that the flow guiding channel 401 is in a completely closed state, and the hand wheel is continuously rotated in the opposite direction, since the length of the sliding groove 402a is equal to the lower end 702. The sum of the lengths of the second valve plate 500, so that the lifting member 700 will lower the first valve plate 400, thereby slowly cutting the medium passage 101 when the first valve plate 400 is lowered to the bottom end of the valve chamber 200. The valve is fully closed. In the present invention, the large-diameter high-pressure valve for oil and gas is generally used in a pressure environment of 15000 PSI. Although the labor-saving device of the ball screw is used, the valve of the original slab gate valve still has a torque of 600-650 N/m during the opening process of the valve, so By performing a full-pressure opening operation by a single person, it is necessary to open the valve with an auxiliary opening device or to open 4 to 5 people together, which requires a lot of manpower and material resources, and labor. The strength of the laborer is very high; and with the solution of the invention, the torque of the valve opening can be stably reduced to 100-130 N/m, and only a single person can be used without the need for a ball screw labor saving device. The operation of opening the valve at full pressure is completed, which greatly reduces the labor intensity and saves the opening time.

It should be noted that the above embodiments are only used to explain the technical solutions of the present invention, and the present invention is not limited thereto. Although the present invention is described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention can be Modifications or equivalents are intended to be included within the scope of the appended claims.

Claims

A composite low-torque slab gate valve includes a valve body (100), a valve chamber (200) and a first valve seat (300), and the valve body (100) is provided with a medium passage for circulating medium in a left-right direction (101) and a valve chamber (200) in an up and down direction, the first valve seat (300) being disposed in the valve chamber (200) and communicating the medium passage (101) at both ends thereof, and The valve chamber (200) is sequentially divided into an upper chamber (201), a middle chamber (202) and a lower chamber (203), and the middle chamber (202) is in communication with the medium passage (101), and is characterized in that: Also includes,

a first valve plate (400) partially inserted into the first valve seat (300) to intercept or communicate the medium passage (101);

a second valve plate (500) disposed in the first valve plate (400), including a second intercepting end (501) and a second transparent end (502), the two being capable of cutting or conducting the first a flow guiding channel (401) disposed in the left and right direction in the valve plate (400), the flow guiding channel (401) being in communication with the medium passage (101);

a second valve seat (600) communicating the flow guiding passages (401) at both ends thereof, and the second valve plate (500) is inserted into the second valve seat (600) to cut off or conduct the guiding Flow channel (401).
The composite low torque slab gate valve of claim 1 wherein said first valve plate (400) further includes a first truncated end (402) and a first permeable end (403).

The first cutting end (402) is a solid portion, and a sliding groove (402a) is disposed on the upper and lower sides, and the second valve plate (500) slides in the sliding groove (402a), and the cutting portion is cut off. The flow guiding channel (401) is a transparent portion capable of correspondingly communicating with the medium channel (101).
The composite low torque slab gate valve according to claim 2, wherein said second valve plate (500) has the same structure as said first valve plate (400), said second cut end (501) As a physical part, the flow guiding channel (401) is cut off, and the second transparent end (502) is a transparent portion, and can communicate with the guiding channel (401).
A composite low torque slab gate valve according to claim 2 or 3, further comprising a lifting member (700) on which a finite projection (701) is disposed, said lifting member (700) being limited The position protrusion (701) is divided into an upper end (701) and a lower end (702),

The lower end (702) is coupled to the second valve plate (500), the inner diameter of the lower end (702) is smaller than the inner diameter of the upper end (701), and the lower end (702) and the sliding groove (402a) A certain gap (S) is formed between the two.
A compound low torque slab gate valve according to claim 4, wherein said first section The break end (402) further includes a limit block (402b) and a contact member (402c),

The limiting block (402b) is capped at a top end of the sliding groove (402a) and connected to a top end of the first valve plate (400), and the abutting member (402c) is disposed at the gap (S) The bottom end is connected to the top end of the second valve plate (500).
A compound low torque slab gate valve according to claim 5, further comprising a valve cover (800), said valve cover (800) being capped at the top end of said valve chamber (200), and said valve Body (100) connection.
The composite low-torque slab gate valve according to claim 6, wherein the bonnet (800) is further provided with a finite position port (801), and the limiting port (801) can be coupled with the limiting position. The (701) limit limits the continued rise of the lifter (700).
The composite low torque slab gate valve according to any one of claims 5, 6 or 7, wherein said sliding groove (402a) has a length equal to said lower end (702) and said second valve plate (500) The sum of the lengths of the two.
The composite low-torque slab gate valve according to claim 8, wherein when the limiting port (801) is in contact with the limiting protrusion (701), the first transparent end (403) Corresponding to the medium channel (101).
The composite low-torque slab gate valve according to claim 9, wherein when the limiting block (402b) is in contact with the abutting member (402c), the flow guiding channel (401) and the first The transparent portion of the two valve plates (500) is correspondingly connected.