Parallel double gate valve

Abstract

The utility model discloses a parallel double gate plate gate valve, including valve body, valve cover, valve rod, support, two gate plates and two valve seats, be equipped with the middle chamber in the valve body, one flow channel is equipped with respectively at the both ends of valve body, the valve cover is installed on the upper end of valve body, and the outer end cooperation and connection of valve rod has hand wheel, and the inner end of valve rod is connected with support and stretches into the middle chamber, two gate plates are installed respectively at the both sides of support, and two valve seats are installed respectively at the junction of corresponding flow channel and middle chamber, are used for when the valve is closed and corresponding gate plate abuts and constitutes sealed cooperation, the junction of flow channel inner end and middle chamber is equipped with annular groove, and the inner diameter of annular groove is greater than the inner diameter of flow channel, so that the annular groove and flow channel form a limit step between, and the fixed ring is detachably installed in the annular groove, and the valve seat is screwed on the inner circular surface of fixed ring, and the end face of valve seat away from gate plate is abutting tightly with limit step. The utility model not only is convenient for early processing production, but also is favorable to later maintenance replacement, and the maintenance cost is lower.

Description

Technical Field

[0001] This utility model relates to the field of valve technology, and in particular to a parallel double gate valve that is easy to disassemble and maintain. Background Technology

[0002] A slab gate valve is a sliding valve with a parallel gate as its closing element. The closing element can be a single gate or a double gate with an opening mechanism. Slab gate valves can be classified by their actuation method into manual, pneumatic, and electric types. They can also be classified by application and usage into slab gate valves with orifices, slab gate valves without orifices, oilfield slab gate valves, pipeline slab gate valves, and gas slab gate valves, etc.

[0003] The working principle of a parallel double gate valve is as follows: the thrust of the valve stem is transmitted to the gate through the force component of the internal valve components, so that the gate and the valve seat are automatically squeezed to form a forced seal.

[0004] Currently, the connection between the valve seat and valve body of a parallel double gate valve is mainly achieved through two methods: welding and threaded connection.

[0005] For example, the utility model patent application CN201310082915.7 discloses an automatic pressure relief structure for a parallel double-gate valve, which includes a valve body, two valve seats, and two gates. The valve seats are embedded in the valve body and welded to it as a whole. A gate is installed inside the valve body that can be tightly attached to or separated from the valve seat under the driving force of the actuator. In this design, the valve seat and valve body are welded together. Because the gate and valve seat form a forced seal when the valve is closed, frequent use will cause wear on the valve seat sealing surface, leading to poor sealing performance. Furthermore, the welded valve seat is difficult to disassemble and replace, making subsequent maintenance difficult.

[0006] For example, the utility model patent with application number CN201320865296.4 discloses a parallel double-gate opening valve core, in which the valve seat is screwed onto the valve body by a threaded connection. Although this connection method is convenient for disassembly and assembly, the thread machining operation on the inner wall of the valve body is relatively difficult, and the internal threads of the valve body are easily damaged by repeated rotation of the valve seat, which makes it impossible to install the valve seat smoothly and thus the valve body is discarded, resulting in high maintenance costs.

[0007] To address the aforementioned issues, there is an urgent need in the market for a parallel double-gate valve that is easy to disassemble and maintain. Utility Model Content

[0008] The purpose of this utility model is to provide a parallel double gate valve. This utility model is not only convenient for early processing and production, but also convenient for later maintenance and replacement, resulting in lower maintenance costs.

[0009] To achieve the above objectives, this utility model provides the following technical solution: a parallel double-gate valve, comprising a valve body, a valve cover, a valve stem, a bracket, two gates, and two valve seats. The valve body has a central cavity, and each end of the valve body has a flow channel communicating with the central cavity. The valve cover is installed on the upper end of the valve body, the valve stem passes through the valve cover, and a handwheel is connected to the outer end of the valve stem. The inner end of the valve stem extends into the central cavity and is connected to the bracket. The two gates are respectively installed on both sides of the bracket, and the two valve seats are respectively installed at the junction of the corresponding flow channel and the central cavity, for sealing with the corresponding gate when the valve is closed. An annular groove is provided at the junction of the inner end of the flow channel and the central cavity. The inner diameter of the annular groove is larger than the inner diameter of the flow channel, so that a limiting step is formed between the annular groove and the flow channel. A fixing ring is detachably installed in the annular groove. The valve seat is threaded to the inner circular surface of the fixing ring, and the end face of the valve seat away from the gate abuts against the limiting step.

[0010] By adopting the above technical solution, a detachable retaining ring is set inside the valve body, and the valve seat is threaded onto the retaining ring. Based on the detachable and replaceable valve seat, this avoids the increased processing difficulty caused by machining threads inside the valve body and the difficulty in repairing subsequent thread damage (i.e., no need to machine threads inside the valve body). Furthermore, the retaining ring can be directly replaced when the threads on the retaining ring are damaged. This greatly facilitates the early processing and production as well as the later maintenance and replacement, and reduces maintenance costs.

[0011] The present invention is further configured such that a plurality of first screw holes are distributed in a circumferential array on the fixing ring, the first screw holes extend radially along the fixing ring, and a plurality of positioning grooves, the number of which is equivalent to the number of the first screw holes, are distributed in a circumferential array on the inner circular surface of the annular groove. Each first screw hole is internally threaded with a stud, and one end of the stud is provided with a positioning protrusion for inserting into the corresponding positioning groove.

[0012] By adopting the above technical solution, the fixing ring is locked in the annular groove by multiple studs and the fixing ring threaded together, so that it cannot rotate circumferentially or move axially, thus realizing the detachable installation of the fixing ring. The connection structure is simple and reliable, and disassembly and assembly are very convenient.

[0013] The present invention is further configured such that the outer diameter of the positioning protrusion is smaller than the outer diameter of the stud, and a tapered limiting part is provided between the positioning protrusion and the stud. After the stud is screwed into the first screw hole, the tapered limiting part abuts against the inner circular surface of the annular groove.

[0014] By adopting the above technical solution, the screw insertion depth is limited by the conical limiting part, which can ensure the accurate installation of the screw and the precise matching between the positioning protrusion and the positioning groove.

[0015] The present invention is further configured such that at least one voltage stabilizing groove is provided on the outer circular surface of the positioning protrusion, and the extending direction of the voltage stabilizing groove is parallel to the extending direction of the positioning protrusion.

[0016] By adopting the above technical solution, the design of the pressure stabilizing groove on the positioning protrusion allows the medium in the positioning groove to be discharged when the positioning protrusion is inserted into the positioning groove. At the same time, when the positioning protrusion leaves the positioning groove, the medium can re-enter the positioning groove, maintaining the pressure balance in the positioning groove, so that the positioning protrusion can smoothly enter or leave the positioning groove.

[0017] The present invention is further configured such that the other end of the stud corresponding to the positioning protrusion is provided with an internal hexagonal groove.

[0018] By adopting the above technical solution, an L-shaped hex screwdriver can be used to rotate the stud, which facilitates its disassembly and assembly.

[0019] The present invention is further configured such that the limiting step is provided with a plurality of positioning protrusions arranged in a circumferential array, and the valve seat is provided with a plurality of positioning recesses that fit with the positioning protrusions.

[0020] By adopting the above technical solution, the valve seat can be pre-installed and positioned so that the first screw hole is aligned with the corresponding positioning groove. After the stud is screwed into the first screw hole, the positioning protrusion can be directly inserted into the positioning groove.

[0021] The present invention is further provided that a sealing ring for forming a sealing fit with the valve seat is installed on the limiting step.

[0022] By adopting the above technical solution, the sealing between the valve seat and the limit step can be guaranteed, and the medium can be prevented from leaking from the gap between the two when the valve is closed.

[0023] The present invention is further configured such that a second threaded hole extending to the inner end face of the limiting step is provided on the outer wall of the valve body, the outer end of the second threaded hole is threaded to an oil inlet connector, and a sealing gasket is provided between the oil inlet connector and the valve body. The valve seat is provided with an L-shaped lubrication channel at one end that is in contact with the limiting step. One end of the lubrication channel is connected to the second threaded hole, and the other end of the lubrication channel extends to the inner circular surface of the fixing ring.

[0024] By adopting the above technical solution, when the valve seat needs to be disassembled, if the threads between the valve seat and the fixed ring become stuck, lubricant can be injected through the oil inlet connector. The lubricant enters the threaded mating surface between the valve seat and the fixed ring through the lubrication channel on the valve seat, reducing the friction coefficient between the two and making it easier to unscrew the valve seat.

[0025] The present invention is further configured such that the lubrication channel has multiple channels, and the multiple lubrication channels are distributed in a circumferential array on the valve seat. An annular flow divider groove is formed on the end face of the valve seat that is in contact with the limiting step. The inner end of the second screw hole is connected to the annular flow divider groove. The end of the lubrication channel near the limiting step is connected to the annular flow divider groove.

[0026] By adopting the above technical solution, the threaded mating surfaces between the valve seat and the fixed ring can be uniformly lubricated in the circumference through multiple lubrication channels, resulting in more comprehensive lubrication and facilitating the rotation operation of the valve seat.

[0027] The present invention is further configured such that an O-ring is installed on the outer periphery and inner periphery of the valve seat corresponding to the annular diversion groove, respectively, for forming a sealing fit with the limiting step.

[0028] By adopting the above technical solution, lubricant leakage through the gap between the valve seat and the limiting step can be avoided, ensuring that the lubricant can effectively enter the threaded mating surface between the valve seat and the fixed ring, and reducing lubricant consumption. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0030] Figure 2 This utility model Figure 1 Enlarged structural diagram of section A in the middle;

[0031] Figure 3 This is a schematic diagram of the structure of the fixing ring of this utility model.

[0032] In the diagram: 1. Valve body; 2. Valve cover; 3. Valve stem; 4. Bracket; 5. Gate; 6. Valve seat; 7. Central cavity; 8. Flow channel; 9. Annular groove; 10. Limiting step; 11. Fixing ring; 12. First screw hole; 13. Positioning groove; 14. Stud; 15. Positioning protrusion; 16. Conical limiting part; 17. Pressure stabilizing groove; 18. Internal hexagonal groove; 19. Positioning protrusion; 20. Positioning recess; 21. Sealing ring; 22. Second screw hole; 23. Oil inlet connector; 24. Sealing gasket; 25. Lubrication channel; 26. Annular diverter groove; 27. O-ring; 28. Handwheel. Detailed Implementation

[0033] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0034] Example: As attached Figures 1-3 The parallel double-gate valve shown includes a valve body 1, a valve cover 2, a valve stem 3, a bracket 4, two gates 5, and two valve seats 6. The valve body 1 has a central cavity 7, and each end of the valve body 1 has a flow channel 8 communicating with the central cavity 7. The valve cover 2 is installed on the upper end of the valve body 1. The valve stem 3 passes through the valve cover 2, and a handwheel 28 is connected to the outer end of the valve stem 3. The inner end of the valve stem 3 extends into the central cavity 7 and connects to the bracket 4. The two gates 5 are respectively installed on both sides of the bracket 4. The connection between the valve stem 3 and the bracket 4, and the connection between the bracket 4 and the gates 5, are existing technologies; therefore, their specific connection structures are not described in detail here. The valve seat 6 is installed at the junction of the corresponding flow channel 8 and the middle cavity 7, and is used to abut against the corresponding gate 5 to form a sealing fit when the valve is closed. An annular groove 9 is provided at the junction of the inner end of the flow channel 8 and the middle cavity 7. The inner diameter of the annular groove 9 is larger than the inner diameter of the flow channel 8, so that a limiting step 10 is formed between the annular groove 9 and the flow channel 8. A fixing ring 11 is detachably installed in the annular groove 9. The valve seat 6 is threaded to the inner circular surface of the fixing ring 11. That is, the outer circular surface of the valve seat 6 has an external thread, and the inner circular surface of the fixing ring 11 has an internal thread that matches the external thread. The end face of the valve seat 6 away from the gate 5 abuts against the limiting step 10. By setting a detachable retaining ring 11 inside the valve body 1 and then threading the valve seat 6 onto the retaining ring 11, the valve seat 6 can be detached and replaced. This avoids the increased processing difficulty caused by machining threads inside the valve body 1 and the difficulty in repairing subsequent thread damage (i.e., no need to machine threads inside the valve body 1). Furthermore, the retaining ring 11 can be directly replaced when the threads on it are damaged. This greatly facilitates the initial processing and production as well as the subsequent maintenance and replacement, and reduces maintenance costs.

[0035] As attached Figure 2 and attached Figure 3 As shown, the fixing ring 11 has a plurality of first screw holes 12 arranged in a circumferential array. The first screw holes 12 extend radially along the fixing ring 11. The inner circular surface of the annular groove 9 has a plurality of positioning grooves 13 arranged in a circumferential array, with a number equivalent to the number of the first screw holes 12. In this embodiment, four positioning grooves 13 are used. Each first screw hole 12 is internally threaded with a stud 14, and one end of the stud 14 is provided with a positioning protrusion 15 for inserting into the corresponding positioning groove 13. The positioning protrusion 15 and the stud 14 are integral structures, and both the positioning protrusion 15 and the positioning groove 13 are cylindrical. By means of multiple studs 14 threadedly engaging with the fixing ring 11, the fixing ring 11 is locked in the annular groove 9, preventing it from rotating circumferentially or displacing axially. This achieves detachable installation of the fixing ring 11, with a simple and reliable connection structure that is very convenient for disassembly and assembly.

[0036] As attached Figure 2and attached Figure 3 As shown, the outer diameter of the positioning protrusion 15 is smaller than the outer diameter of the stud 14, and a tapered limiting part 16 is provided between the positioning protrusion 15 and the stud 14. After the stud 14 is screwed into the first screw hole 12, the tapered limiting part 16 abuts against the inner circular surface of the annular groove 9. By limiting the screwing depth of the stud 14 by the tapered limiting part 16, the precise installation of the stud 14 and the precise fit between the positioning protrusion 15 and the positioning groove 13 can be ensured.

[0037] As attached Figure 2 and attached Figure 3 As shown, at least one pressure-stabilizing groove 17 is formed on the outer circular surface of the positioning protrusion 15. The cross-section of the pressure-stabilizing groove 17 can be rectangular or semi-circular, and the extending direction of the pressure-stabilizing groove 17 is parallel to the extending direction of the positioning protrusion 15. The design of the pressure-stabilizing groove 17 on the positioning protrusion 15 allows the medium in the positioning groove 13 to be discharged when the positioning protrusion 15 is inserted into the positioning groove 13. At the same time, when the positioning protrusion 15 is removed from the positioning groove 13, the medium can re-enter the positioning groove 13, maintaining the pressure balance in the positioning groove 13, so that the positioning protrusion 15 can smoothly enter or leave the positioning groove 13.

[0038] As attached Figure 2 As shown, the stud 14 has an internal hexagonal groove 18 at the other end corresponding to the positioning protrusion 15. An L-shaped hexagonal screwdriver can be used to rotate the stud 14, which facilitates its assembly and disassembly.

[0039] As attached Figure 2 and attached Figure 3 As shown, the limiting step 10 is provided with a plurality of positioning protrusions 19 arranged in a circumferential array, and the valve seat 6 is provided with a plurality of positioning recesses 20 that fit with the positioning protrusions 19. In this embodiment, there are four positioning protrusions 19 and four positioning recesses 20. By pre-installing and positioning the valve seat 6, the first screw hole 12 can be aligned with the corresponding positioning groove 13, and after the stud 14 is screwed into the first screw hole 12, the positioning protrusion 15 can be directly inserted into the positioning groove 13.

[0040] As attached Figure 2 As shown, a sealing ring 21 is installed on the limiting step 10 to form a sealing fit with the valve seat 6. This design ensures the sealing between the valve seat 6 and the limiting step 10, preventing the medium from leaking from the gap between them when the valve is closed.

[0041] As attached Figure 2 and attached Figure 3As shown, a second threaded hole 22 extending to the inner end face of the limiting step 10 is also provided on the outer wall of the valve body 1. An oil inlet connector 23 is threadedly connected to the outer end of the second threaded hole 22. The oil inlet connector 23 is an oil inlet connector 23 with a one-way valve, which is a product that can be directly purchased on the market. Therefore, its structure will not be described in detail here. A sealing gasket 24 is provided between the oil inlet connector 23 and the valve body 1. The end of the valve seat 6 that is in contact with the limiting step 10 is provided with a lubrication channel 25 with an L-shaped cross section. One end of the lubrication channel 25 is connected to the second threaded hole 22, and the other end of the lubrication channel 25 extends to the inner circular surface of the fixing ring 11. When it is necessary to disassemble the valve seat 6, if the threads of the valve seat 6 and the fixing ring 11 become stuck, lubricant can be injected through the oil inlet connector 23. The lubricant enters the threaded mating surface of the valve seat 6 and the fixing ring 11 through the lubrication channel 25 on the valve seat 6, reducing the friction coefficient between the two and making it easier to unscrew the valve seat 6.

[0042] As attached Figure 2 and attached Figure 3 As shown, there are multiple lubrication channels 25, which are arranged in a circumferential array on the valve seat 6. In this embodiment, there are four lubrication channels 25. An annular flow divider groove 26 is formed on the end face of the valve seat 6 that is in contact with the limiting step 10. The inner end of the second screw hole 22 is connected to the annular flow divider groove 26. The end of the lubrication channel 25 near the limiting step 10 is connected to the annular flow divider groove 26. Through multiple lubrication channels 25, the threaded mating surfaces between the valve seat 6 and the fixing ring 11 can be uniformly lubricated in the circumferential direction, resulting in more comprehensive lubrication and facilitating the rotation operation of the valve seat 6.

[0043] As attached Figure 2 and attached Figure 3 As shown, an O-ring 27 is installed on the outer periphery and inner periphery of the valve seat 6 corresponding to the annular diversion groove 26, respectively, to form a sealing fit with the limiting step 10. This design can prevent lubricant leakage through the gap between the valve seat 6 and the limiting step 10, ensuring that the lubricant can effectively enter the threaded mating surface between the valve seat 6 and the fixing ring 11, and reducing lubricant consumption.

Claims

1. A parallel double-gate valve, comprising a valve body (1), a valve cover (2), a valve stem (3), a bracket (4), two gates (5), and two valve seats (6), wherein the valve body (1) has a central cavity (7), and each end of the valve body (1) is provided with a flow channel (8) communicating with the central cavity (7), the valve cover (2) is installed on the upper end of the valve body (1), the valve stem (3) passes through the valve cover (2), and the outer end of the valve stem (3) is fitted with a handwheel (28), the inner end of the valve stem (3) extends into the central cavity (7) and is connected to the bracket (4), the two gates (5) are respectively installed on both sides of the bracket (4), and the two valve seats (6) are respectively installed at the junction of the corresponding flow channel (8) and the central cavity (7), for sealing with the corresponding gate (5) when the valve is closed; characterized in that: An annular groove (9) is provided at the junction of the inner end of the flow channel (8) and the middle cavity (7). The inner diameter of the annular groove (9) is larger than the inner diameter of the flow channel (8), so that a limiting step (10) is formed between the annular groove (9) and the flow channel (8). A fixing ring (11) is detachably installed in the annular groove (9). The valve seat (6) is threaded to the inner circular surface of the fixing ring (11), and the end face of the valve seat (6) away from the gate (5) abuts against the limiting step (10).

2. The parallel double-gate valve according to claim 1, characterized in that: The fixing ring (11) has a plurality of first screw holes (12) arranged in a circumferential array. The first screw holes (12) extend radially along the fixing ring (11). The inner circular surface of the annular groove (9) has a plurality of positioning grooves (13) arranged in a circumferential array, which are equivalent in number to the first screw holes (12). Each first screw hole (12) is threaded with a stud (14), and one end of the stud (14) is provided with a positioning protrusion (15) for inserting into the corresponding positioning groove (13).

3. A parallel double-gate valve according to claim 2, characterized in that: The outer diameter of the positioning protrusion (15) is smaller than the outer diameter of the stud (14), and a tapered limiting part (16) is provided between the positioning protrusion (15) and the stud (14). After the stud (14) is screwed into the first screw hole (12), the tapered limiting part (16) abuts against the inner circular surface of the annular groove (9).

4. A parallel double-gate valve according to claim 2, characterized in that: At least one voltage stabilizing groove (17) is provided on the outer circular surface of the positioning protrusion (15), and the extending direction of the voltage stabilizing groove (17) is parallel to the extending direction of the positioning protrusion (15).

5. A parallel double-gate valve according to claim 2, characterized in that: The stud (14) has an internal hexagonal groove (18) at the other end corresponding to the positioning protrusion (15).

6. A parallel double-gate valve according to claim 2, characterized in that: The limiting step (10) is provided with a plurality of positioning protrusions (19) arranged in a circular array, and the valve seat (6) is provided with a plurality of positioning recesses (20) that fit with the positioning protrusions (19).

7. A parallel double-gate valve according to claim 1, characterized in that: A sealing ring (21) is installed on the limiting step (10) for forming a sealing fit with the valve seat (6).

8. A parallel double-gate valve according to claim 1, characterized in that: The valve body (1) is also provided with a second screw hole (22) extending to the inner end face of the limiting step (10). The outer end of the second screw hole (22) is threaded with an oil inlet connector (23), and a sealing gasket (24) is provided between the oil inlet connector (23) and the valve body (1). The valve seat (6) is provided with a lubrication channel (25) with an L-shaped cross section at one end that is in contact with the limiting step (10). One end of the lubrication channel (25) is connected to the second screw hole (22), and the other end of the lubrication channel (25) extends to the inner circle surface of the fixing ring (11).

9. A parallel double-gate valve according to claim 8, characterized in that: The lubrication channel (25) has multiple channels, and the multiple lubrication channels (25) are arranged in a circumferential array on the valve seat (6). An annular flow divider groove (26) is provided on the end face of the valve seat (6) that is in contact with the limiting step (10). The inner end of the second screw hole (22) is connected to the annular flow divider groove (26). The end of the lubrication channel (25) near the limiting step (10) is connected to the annular flow divider groove (26).

10. A parallel double-gate valve according to claim 8, characterized in that: The valve seat (6) is equipped with an O-ring (27) at the outer periphery and inner periphery of the annular diversion groove (26) respectively, which is used to form a sealing fit with the limiting step (10).

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