A high-airtightness chemical raw material conveying shut-off valve

Abstract

This utility model discloses a high-airtightness chemical raw material conveying shut-off valve, relating to the field of shut-off valve technology. It includes a valve body, a valve cover, and a valve stem. The valve body has a valve seat inside, and the lower end of the valve stem has a first valve disc adapted to the valve seat. A second valve disc adapted to the valve seat is slidably connected below the first valve disc. The second valve disc is hollow with an open upper end and contains an elastic element. A connecting rod connects the elastic element and the first valve disc, and the connecting rod is slidably inserted into the second valve disc. This utility model achieves a double hard seal; even if one layer of seal fails, the other layer can still ensure effective sealing of the medium, effectively improving the valve's sealing performance. Furthermore, a soft seal can be achieved between the second valve disc and the valve seat, further improving the valve's sealing performance. The second valve disc also has an elastic compensation function to prevent loosening and leakage between the second valve disc and the second sealing bevel after the valve is subjected to vibration.

Description

Technical Field

[0001] This utility model relates to the field of gate valve technology, and in particular to a high airtightness gate valve for conveying chemical raw materials. Background Technology

[0002] Gate valves, also known as shut-off valves, are among the most widely used valves. They play a crucial role in cutting off and throttling the medium in the pipeline they are connected to. As an extremely important type of shut-off valve, the gate valve seals by applying torque to the valve stem. The valve stem applies pressure to the valve disc in the axial direction, causing the valve disc sealing surface to fit tightly against the valve seat sealing surface, preventing the medium from leaking along the gap between the sealing surfaces. Because gate valves have a small opening height during opening and closing, are easy to adjust the flow rate, are convenient to manufacture and maintain, and have a wide range of applicable pressures, they are widely used in the field of chemical raw material transportation.

[0003] However, traditional gate valves achieve the effect of sealing the medium by only one valve disc cooperating with the valve seat. After a period of use, if wear occurs between the valve disc and the valve seat, the sealing performance will easily decline, which will have a certain impact on the transportation of chemical raw materials. Utility Model Content

[0004] The purpose of this invention is to solve the problem that the existing technology relies on only one valve disc and valve seat for sealing, which easily leads to a decrease in sealing performance after wear. Therefore, a high airtightness chemical raw material conveying shut-off valve is proposed.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A high-airtightness chemical raw material conveying shut-off valve includes a valve body, a valve cover, and a valve stem. The valve body has a valve seat inside. The lower end of the valve stem has a first valve disc adapted to the valve seat. A second valve disc adapted to the valve seat is slidably connected below the first valve disc. The interior of the second valve disc is hollow with an open upper end and has an elastic element inside. A connecting rod is connected between the elastic element and the first valve disc. The connecting rod is slidably inserted into the second valve disc.

[0006] In some embodiments, the valve seat has a first valve seat hole and a second valve seat hole arranged sequentially from top to bottom inside. The inner diameter of the first valve seat hole is larger than the inner diameter of the second valve seat hole, and the upper end of the first valve seat hole has a first sealing slope adapted to the first valve disc, and the interior of the second valve seat hole has a second sealing slope adapted to the second valve disc.

[0007] In some embodiments, a sealing airbag ring is fitted around the outside of the second valve disc to seal the outer wall of the second valve disc with the inner wall of the first valve seat hole.

[0008] In some embodiments, the elastic element includes an upper cover plate, a lower cover plate, and a soft sealing ring, wherein the upper cover plate, the lower cover plate, and the soft sealing ring form an elastic airbag, and a connecting pipe is connected between the upper cover plate and the sealing airbag ring.

[0009] In some embodiments, the upper cover plate is fixedly connected to the connecting rod, and the lower cover plate is fixedly connected to the inside of the second valve disc.

[0010] In some embodiments, a guide post is fixedly connected to the lower surface of the upper cover plate, a guide sleeve is fixedly connected to the upper surface of the lower cover plate, the guide post is slidably connected to the guide sleeve, and a spring sleeved outside the guide sleeve is connected between the upper cover plate and the lower cover plate.

[0011] In some embodiments, a sealing cover is detachably connected to the upper opening of the second valve disc, a sealing gasket is provided between the sealing cover and the second valve disc, the sealing cover is sleeved on the outside of the connecting rod, and a sliding sealing ring is provided on the sealing cover that is sleeved on the outside of the connecting rod.

[0012] In some embodiments, the connecting rod includes a connecting post and a limiting ring, the diameter of the limiting ring being larger than the diameter of the connecting post, and the limiting ring being connected to the upper end of the connecting post by a screw.

[0013] In some embodiments, a groove is provided on the lower surface of the first valve disc, and a connecting cover is sleeved on the upper end of the connecting column and the outside of the limiting ring. The connecting cover is connected to the groove by bolts.

[0014] Compared with the prior art, this utility model provides a highly airtight chemical raw material conveying shut-off valve, which has the following beneficial effects: 1. By cooperating with the valve seat, the first valve disc, and the second valve disc, the valve can achieve a double hard seal after being closed, thereby effectively improving the valve's sealing performance. Even if one layer of seal fails, the other layer can still ensure that the valve can effectively seal the medium. This can improve the reliability and service life of the sealing components to a certain extent and ensure the normal operation of chemical raw material transportation. 2. By cooperating with the elastic element and the sealing air ring, during the valve closing process, the compression of the elastic element can inflate the sealing ring and cause it to expand and deform to a certain extent. This allows the sealing ring to fit tightly against the inner wall of the first valve seat hole and the outer wall of the second valve disc, thereby achieving a soft seal between the second valve disc and the valve seat. This further improves the valve's sealing performance and ensures a better sealing effect. 3. By setting the elastic element, after the valve is closed, the elastic element can have high elasticity, thereby realizing the elastic compensation function of the second valve disc. When wear occurs between the second valve disc and the second sealing slope, the elastic element's rebound force can push the second valve disc downward for a certain displacement compensation, so that the second valve disc can still be tightly attached to the second sealing slope, ensuring the sealing performance between the two. Furthermore, when the valve is subjected to a certain vibration, the elastic force provided by the elastic element can still ensure the tight fit between the second valve disc and the second sealing slope, preventing loosening and leakage between the two. 4. During the valve opening and closing process, there is no sliding friction between the sealing airbag ring and the valve seat, which effectively prevents damage to the surface of the sealing airbag ring due to friction. Therefore, it can play a certain protective role for the sealing airbag ring and ensure its service life.

[0015] Other advantages, objectives and features of this invention will be set forth in part in the description which follows; and in part will be apparent to those skilled in the art upon examination of the following description; or may be taught from practice of this invention. Attached Figure Description

[0016] Figure 1 This is a frontal cross-sectional three-dimensional structural diagram of the present invention in its closed state; Figure 2 This is a frontal cross-sectional view of the structure of this utility model in its open state; Figure 3 This is a frontal three-dimensional structural diagram of the second valve disc. Figure 4 A schematic diagram of the three-dimensional structure of the explosion at the second valve disc; Figure 5 This is a frontal three-dimensional structural diagram of the valve seat; Figure 6 This is a partial structural diagram of the present invention viewed from the front and in cross-section. Figure 7 This is a schematic diagram of the front sectional view of the second valve disc.

[0017] In the diagram: 1. Valve body; 2. Valve cover; 3. Valve stem; 301. Threaded cap; 302. Handwheel; 4. Valve seat; 401. First valve seat hole; 402. Second valve seat hole; 403. First sealing bevel; 404. Second sealing bevel; 5. First valve disc; 501. Groove; 6. Second valve disc; 601. Sealing cap; 602. Sealing gasket; 603. Sliding sealing ring; 7. Connecting rod; 701. Connecting post; 702. Limiting ring; 703. Screw; 8. Elastic element; 801. Upper cover plate; 802. Lower cover plate; 803. Sealing connecting ring; 804. Spring; 805. Guide sleeve; 806. Guide post; 9. Sealing airbag ring; 10. Connecting pipe; 11. Connecting cap. Detailed Implementation

[0018] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0019] Reference Figure 1-2 A high-airtightness chemical raw material conveying shut-off valve includes a valve body 1, a valve cover 2, and a valve stem 3. The valve cover 2 is fixedly and sealed to the upper end of the valve body 1 by bolts. The outer surface of the valve stem 3 is threaded and threadedly connected to the valve cover 2. A handwheel 302 is fixedly connected to the upper end of the valve stem 3. A valve seat 4 is fixedly installed inside the valve body 1. The lower end of the valve stem 3 is provided with a first valve disc 5 that matches the valve seat 4. A second valve disc 6 that matches the valve seat 4 is slidably connected below the first valve disc 5. Both the lower ends of the first valve disc 5 and the lower ends of the second valve disc 6 are provided with chamfered bevels. The valve seat 4, the first valve disc 5, and the second valve disc 6 are made of hard sealing materials such as stainless steel, alloy steel, and copper alloy.

[0020] Reference Figure 5-6 The valve seat 4 has a first valve seat hole 401 and a second valve seat hole 402 sequentially formed from top to bottom inside. The inner diameter of the first valve seat hole 401 is larger than the inner diameter of the second valve seat hole 402. The upper end of the first valve seat hole 401 is provided with a first sealing slope 403 that matches the lower chamfered slope of the first valve disc 5. The interior of the second valve seat hole 402 is provided with a second sealing slope 404 that matches the lower chamfered slope of the second valve disc 6.

[0021] Reference Figure 3-4 The interior of the second valve disc 6 is hollow with an opening at the top and has an elastic element 8 inside. A connecting rod 7 is connected between the elastic element 8 and the first valve disc 5. The connecting rod 7 is slidably inserted into the second valve disc 6.

[0022] Reference Figure 6The outer side of the second valve disc 6 is fitted with a sealing airbag ring 9, which is used to seal the outer wall of the second valve disc 6 with the inner wall of the first valve seat hole 401. When the sealing airbag ring 9 is not inflated, its outer diameter is smaller than the inner diameter of the first valve seat hole 401.

[0023] Reference Figure 6-7 The elastic element 8 includes an upper cover plate 801, a lower cover plate 802, and a soft sealing ring 803. The upper cover plate 801, the lower cover plate 802, and the soft sealing ring 803 form an elastic airbag, and a connecting pipe 10 connects the upper cover plate 801 and the sealing airbag ring 9. The upper cover plate 801 is fixedly connected to the connecting rod 7, and the lower cover plate 802 is fixedly connected to the inside of the second valve disc 6.

[0024] A guide post 806 is fixedly connected to the lower surface of the upper cover plate 801, and a guide sleeve 805 is fixedly connected to the upper surface of the lower cover plate 802. The guide post 806 is slidably connected to the guide sleeve 805, and a spring 804 sleeved on the outside of the guide sleeve 805 is connected between the upper cover plate 801 and the lower cover plate 802 to increase the elastic force of the elastic element 8.

[0025] Reference Figure 3 , Figure 4 as well as Figure 7 A sealing cover 601 is detachably connected to the upper opening of the second valve disc 6. Specifically, the second valve disc 6 is connected to the sealing cover 601 by bolts. A sealing gasket 602 is provided between the sealing cover 601 and the second valve disc 6 to ensure the sealing between the second valve disc 6 and the sealing cover 601. The sealing cover 601 is sleeved on the outside of the connecting rod 7, and a sliding sealing ring 603 is provided on the sealing cover 601 and sleeved on the outside of the connecting rod 7 to ensure the sealing between the sealing cover 601 and the connecting rod 7, and to achieve the purpose of sealing the inside of the second valve disc 6. This can effectively prevent the medium from entering the second valve disc 6, and thus play a certain role in protecting the components inside the second valve disc 6.

[0026] The sealing airbag ring 9, sealing gasket 602, sliding sealing ring 603, and sealing connecting ring 803 can all be made of soft sealing materials such as polytetrafluoroethylene, perfluoroether rubber, and fluororubber, which can ensure reliable sealing performance while also having good corrosion resistance.

[0027] Reference Figure 7 The connecting rod 7 includes a connecting post 701 and a limiting ring 702. The diameter of the limiting ring 702 is larger than the diameter of the connecting post 701, and the limiting ring 702 is connected to the upper end of the connecting post 701 by a screw 703.

[0028] Reference Figure 6The lower surface of the first valve disc 5 has a groove 501. The upper end of the connecting post 701 is sleeved with the outer side of the limiting ring 702 and the connecting cover 11 is connected to the groove 501 by bolts. The upper surface of the first valve disc 5 has a valve stem mounting hole. The lower end of the valve stem 3 is inverted T-shaped and inserted into the valve stem mounting hole. The lower part of the valve stem 3 is also sleeved with a threaded cap 301. The threaded cap 301 is threaded into the valve stem mounting hole and presses on the inverted T-shaped step at the lower end of the valve stem 3, thereby realizing the detachable connection between the valve stem 3 and the first valve disc 5.

[0029] In this utility model, the valve's open state is as follows: Figure 2 As shown, the medium flows from left to right, passing sequentially through the second valve seat hole 402 and the first valve seat hole 401. When the valve needs to be closed, the valve stem 3 is turned by handwheel 302, which in turn moves the first valve disc 5 and the second valve disc 6 downwards. During this process, the second valve disc 6 passes through the first valve seat hole 401 and inserts into the second sealing slope 404 on the second valve seat hole 402 through its chamfered lower end, thus achieving the first layer of hard seal. Then, the rotation of the valve stem 3 continues to move the first valve disc 5 downwards, inserting its chamfered lower end into the first sealing slope 403, thus achieving the second layer of hard seal. The two layers of hard seals can effectively improve the sealing performance of the valve. Even if one layer of seal fails, the other layer can still ensure that the valve can effectively seal the medium.

[0030] Furthermore, during the valve closing process, the sealing airbag ring 9 will also be inserted into the first valve seat hole 401 along with the second valve disc 6. After the second valve disc 6 contacts and seals with the second sealing slope 404, the second valve disc 6 stops moving downwards due to the obstruction of the second sealing slope 404, while the first valve disc 5 will continue to move downwards until it contacts and seals with the first sealing slope 403. During this process, the first valve disc 5 will push the connecting rod 7 to slide downwards on the second valve disc 6, thereby squeezing the upper cover plate 801, causing the upper cover plate 801 to slide downwards, and causing the sealing connecting ring 803 to... A certain degree of deformation compresses the internal space of the elastic airbag formed by the upper cover plate 801, the lower cover plate 802, and the sealing ring 803. At this time, some of the air in the sealing airbag enters the sealing ring 803 through the connecting pipe 10, thereby inflating the sealing ring 803 and causing it to expand and deform to a certain extent. This causes the sealing ring 803 to be tightly attached to the inner wall of the first valve seat hole 401 and the outer wall of the second valve disc 6, thereby achieving a soft seal between the second valve disc 6 and the valve seat 4, and further improving the sealing performance of the valve.

[0031] Furthermore, during the downward pressing of the upper cover plate 801 by the connecting rod 7, the downward movement of the upper cover plate 801 will also compress the spring 804 to a certain extent. Combined with the elastic airbag formed by the upper cover plate 801, the lower cover plate 802, and the sealing connecting ring 803, the elastic element 8 can have high elasticity, thereby realizing the elastic compensation function of the second valve disc 6. When wear occurs between the second valve disc 6 and the second sealing slope 404, the rebound force of the elastic element 8 can push the second valve disc 6 downward to perform a certain displacement compensation, so that the second valve disc 6 can still be tightly attached to the second sealing slope 404, ensuring the sealing performance between the two. Moreover, when the valve is subjected to a certain vibration, the elastic force provided by the elastic element 8 can still ensure the tight fit between the second valve disc 6 and the second sealing slope 404, preventing the two from loosening and leaking.

[0032] When the valve needs to be opened, the valve stem 3 is turned in the opposite direction by handwheel 302, which pulls the first valve disc 5 upward and separates it from the first sealing slope 403. During this process, spring 804 rebounds and pushes the upper cover plate 801 to slide upward and reset. During this process, the elastic airbag formed by the upper cover plate 801, lower cover plate 802 and sealing connecting ring 803 rebounds, and some air in the sealing airbag ring 9 is drawn back into the elastic airbag rebound through the connecting pipe 10, thereby separating the outer diameter of the sealing airbag ring 9 from the inner wall of the first valve seat hole 401. When the elastic airbag returns to its original state, the first valve disc 5, along with the elastic element 8 and the second valve disc 6 pulled upward by the connecting rod 7, moves back to their original positions, thereby separating the second valve disc 6 from the second sealing slope 404 and opening the valve. Moreover, as can be seen from the above, there is no sliding friction between the sealing airbag ring 9 and the valve seat 4 during the valve opening and closing process, which can prevent damage to the surface of the sealing airbag ring 9 due to friction.

[0033] When it is necessary to inspect the first valve disc 5 and the second valve disc 6, the valve cover 2 can be removed from the valve body 1 first, and the first valve disc 5 and the second valve disc 6 can be removed from the valve body 1 at the same time. Then, the valve stem 3 can be separated from the first valve disc 5 by unscrewing the threaded cap 301. Then, the connecting rod 7 can be separated from the first valve disc 5 by unscrewing the bolt between the connecting cover 11 and the first valve disc 5, thereby separating the second valve disc 6 from the first valve disc 5. Finally, the screw 703 can be unscrewed to connect the limiting ring 702 to the connecting rod 7. After separating the column 701, unscrew the bolts between the second valve disc 6 and the sealing cover 601 to separate the sealing cover 601 from the second valve disc 6. Then, slide the sealing cover 601 upward to separate it from the connecting column 701, thereby opening the second valve disc 6. After that, the internal elastic element 8 and the connecting pipe 10 can be inspected. Therefore, while ensuring that the valve's sealing element has high sealing performance, it also ensures the convenience of subsequent maintenance and repair of related components.

[0034] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

[0035] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

Claims

1. A high-airtightness chemical raw material conveying shut-off valve, comprising a valve body (1), a valve cover (2), and a valve stem (3), wherein a valve seat (4) is provided inside the valve body (1), characterized in that: The lower end of the valve stem (3) is provided with a first valve disc (5) that is adapted to the valve seat (4). A second valve disc (6) adapted to the valve seat (4) is slidably connected below the first valve disc (5). The interior of the second valve disc (6) is hollow with an open upper end and is provided with an elastic element (8). A connecting rod (7) is connected between the elastic element (8) and the first valve disc (5). The connecting rod (7) is slidably inserted into the second valve disc (6). A sealing airbag ring (9) is fitted around the outside of the second valve disc (6) to seal the outer wall of the second valve disc (6) with the inner wall of the valve seat (4); The elastic element (8) includes an upper cover plate (801), a lower cover plate (802) and a soft sealing ring (803). The upper cover plate (801), the lower cover plate (802) and the soft sealing ring (803) form an elastic airbag, and a connecting pipe (10) is connected between the upper cover plate (801) and the sealing airbag ring (9).

2. The high airtightness chemical raw material conveying shut-off valve according to claim 1, characterized in that: The valve seat (4) has a first valve seat hole (401) and a second valve seat hole (402) sequentially arranged from top to bottom inside. The inner diameter of the first valve seat hole (401) is larger than the inner diameter of the second valve seat hole (402). The upper end of the first valve seat hole (401) is provided with a first sealing slope (403) that matches the first valve disc (5). The interior of the second valve seat hole (402) is provided with a second sealing slope (404) that matches the second valve disc (6).

3. The high airtightness chemical raw material conveying shut-off valve according to claim 1, characterized in that: The upper cover plate (801) is fixedly connected to the connecting rod (7), and the lower cover plate (802) is fixedly connected to the inside of the second valve disc (6).

4. The high airtightness chemical raw material conveying shut-off valve according to claim 1, characterized in that: The lower surface of the upper cover plate (801) is fixedly connected to a guide post (806), and the upper surface of the lower cover plate (802) is fixedly connected to a guide sleeve (805). The guide post (806) is slidably connected to the guide sleeve (805), and a spring (804) sleeved on the outside of the guide sleeve (805) is connected between the upper cover plate (801) and the lower cover plate (802).

5. The high airtightness chemical raw material conveying shut-off valve according to claim 1, characterized in that: A sealing cover (601) is detachably connected to the upper opening of the second valve disc (6). A sealing gasket (602) is provided between the sealing cover (601) and the second valve disc (6). The sealing cover (601) is sleeved on the outside of the connecting rod (7), and a sliding sealing ring (603) is provided on the sealing cover (601) and sleeved on the outside of the connecting rod (7).

6. The high airtightness chemical raw material conveying shut-off valve according to claim 1, characterized in that: The connecting rod (7) includes a connecting post (701) and a limiting ring (702). The diameter of the limiting ring (702) is larger than the diameter of the connecting post (701), and the limiting ring (702) is connected to the upper end of the connecting post (701) by a screw (703).

7. The high airtightness chemical raw material conveying shut-off valve according to claim 6, characterized in that: The lower surface of the first valve disc (5) is provided with a groove (501), and the upper end of the connecting column (701) is sleeved with a connecting cover (11) on the outside of the limiting ring (702). The connecting cover (11) is connected to the groove (501) by bolts.

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