Check valve with hard sealing characteristic

Abstract

The technical scheme of the utility model discloses a check valve with a hard sealing characteristic. The check valve comprises a valve seat, a valve plate, a connecting clamping plate, a cylindrical pin, a screwed plug, an upper sealing cavity, a lower sealing cavity and a horizontal limiting structure, the valve plate is arranged in the valve seat, the valve seat and the valve plate are connected through the connecting clamping plate, the connecting clamping plate and the valve plate are fixed through the cylindrical pin, the upper portion of the valve seat is provided with an upper sealing cavity, the lower portion of the valve seat is provided with a lower sealing cavity, the upper portion of the valve plate and the upper sealing cavity are sealed in a matched mode, and the lower portion of the valve plate and the lower sealing cavity are sealed in a matched mode. A horizontal limiting structure is arranged in the middle of the valve seat and limits the maximum rotation angle of the valve plate to be 90 degrees. A screwed plug is arranged on the outer side of the connecting clamping plate and arranged in the valve seat. Through cooperation of the valve plate, the connecting clamping plate, the valve seat, the horizontal limiting structure and the like, rotary opening or closing of the valve plate is achieved, and gas backflow is effectively blocked by combining the metal plane sealing characteristic of the valve plate.

Description

Technical Field

[0001] The utility model belongs to the technical field of control valves, and in particular relates to a check valve with hard sealing characteristics. Background Art

[0002] A check valve is a type of valve whose opening and closing parts are valve plates. It relies on its own weight and the pressure of the medium to produce a movement to block the backflow of the medium. It belongs to the category of automatic valves and is also called non-return valve, one-way valve, reflux valve or isolation valve. The movement of the valve plate is divided into lifting type and swing type. In centrifugal chillers, swing check valves are usually used. They are fixed between the compressor exhaust flange and the condenser inlet flange by clamping. The check valve and the two flanges are sealed with gaskets, and the whole is fastened by bolts. When the centrifugal chiller is operating normally, the gaseous refrigerant can be transported normally. When the centrifugal chiller stops due to a fault, the refrigerant gas will flow back to the compressor, generating an instantaneous impact force on the centrifuge impeller, causing the rear end of the impeller to bear alternating loads, thereby affecting the service life of the core power component impeller. The check valve can prevent the gaseous refrigerant from flowing back. The check valves currently on the market are expensive and have long lead times. Damaged check valves need to be replaced as a whole, and the specifications and models of existing check valves are insufficient to meet the process requirements of centrifugal chillers.

[0003] Patent CN111336283 B discloses a micro-pressure loss check valve, which includes a valve body, a valve plate provided inside the valve body, the valve body and the valve plate are sealed by a sealing table, the inner cavity of the valve body is provided with a left guide limit block and a right guide limit block; the edge area of ​​the left guide limit block is formed with a left limit edge, and the left guide limit block is provided with a left hole; the edge area of ​​the right guide limit block is formed with a right limit edge, and the right guide limit block is provided with a right hole; the left hole is provided with a left eccentric shaft, and the eccentric position of the left eccentric shaft forms a left rotating shaft; the right hole is provided with a right eccentric shaft. The right eccentric shaft has a right rotating shaft formed at an eccentric position; the left ear body is provided with a left shaft hole, and the right ear body is provided with a right shaft hole. The left rotating shaft extends into the left shaft hole, and the right rotating shaft extends into the right shaft hole. The valve plate rotates around the axis of the left and right rotating shafts, and the center line connecting the left and right shaft holes is located at the eccentric position of the valve plate. This allows the fluid to flow only in the required direction, solves the problem of large fluid resistance, and eliminates valve plate vibration. However, the limiting structure when the valve is opened is complex, prone to failure, and complex to maintain. Therefore, it is necessary to develop a check valve that is easy to maintain, has hard sealing characteristics, and is suitable for centrifugal chillers. Utility Model Content

[0004] In order to solve the existing technical problems, the utility model provides a check valve with hard sealing characteristics. Through the cooperation of the valve plate, connecting clamp, valve seat and horizontal limit structure, the valve plate can be rotated to open or close, and combined with the metal plane sealing characteristics of the valve plate, it can effectively prevent gas backflow.

[0005] The technical solution of the utility model is: a check valve with hard sealing characteristics, including a valve seat, a valve plate, a connecting splint, a cylindrical pin, a wire plug, an upper sealing cavity, a lower sealing cavity and a horizontal limiting structure; the valve plate is arranged inside the valve seat, the valve seat and the valve plate are connected by a connecting splint, the connecting splint and the valve plate are fixed by a cylindrical pin, an upper sealing cavity is arranged on the upper part of the valve seat, a lower sealing cavity is arranged on the lower part of the valve seat, the upper part of the valve plate cooperates with the upper sealing cavity for sealing, the lower part of the valve plate cooperates with the lower sealing cavity for sealing, a horizontal limiting structure is arranged in the middle of the valve seat, and the horizontal limiting structure limits the rotation angle of the valve plate to a maximum of 90°; a wire plug is arranged on the outer side of the connecting splint, and the wire plug is arranged inside the valve seat.

[0006] Furthermore, the rotation center of the valve plate is the center of the cylindrical pin, the rotation center of the valve plate is arranged above the center line of the valve plate, and the eccentricity ratio is 4 / 6, 4.5 / 5.5 or 3 / 7.

[0007] Furthermore, the upper sealing chamber is arranged on the rear side of the valve plate, and the lower sealing chamber is arranged on the front side of the valve plate. When the valve plate is in a closed state, the rear end face of the valve plate is in close contact with the upper sealing chamber, and the front end face of the valve plate is in close contact with the lower sealing chamber.

[0008] Furthermore, the horizontal limiting structure includes a horizontal limiting structure I and a horizontal limiting structure II. When the valve plate rotates 90 degrees, the horizontal limiting structure I contacts the front end surface of the valve plate, and the horizontal limiting structure II contacts the rear end surface of the valve plate.

[0009] Furthermore, the connecting splint includes a concave groove, a stepped shaft and a cylindrical pin hole I, the stepped shaft is connected to the rear end of the concave groove, the valve plate is installed in the concave groove, the stepped shaft is installed in the valve seat, the cylindrical pin hole I passes through the stepped shaft along the axis to the concave groove, and the cylindrical pin holes II are symmetrically arranged at the left and right ends of the valve plate. The cylindrical pin is installed in the cylindrical pin hole I and the cylindrical pin hole II, and the cylindrical pin is interference fit with the cylindrical pin hole I and the cylindrical pin hole II.

[0010] Furthermore, a countersunk hole is provided at the rear end of the cylindrical pin hole 1, and a screw hole is provided at the top of the cylindrical pin.

[0011] Furthermore, connecting plate assembly holes are symmetrically arranged on the left and right sides of the inner wall of the valve seat, radial sealing holes are arranged outside the connecting plate assembly holes, the stepped shaft of the connecting plate is installed in the connecting plate assembly hole, and the screw plug is installed in the radial sealing hole.

[0012] Furthermore, a gasket is provided between the thread plug and the connecting splint, and the gasket is provided in the radial sealing hole.

[0013] When the utility model is installed, the connecting splint is inserted into the connecting splint assembly hole from the inside of the valve seat, so that the stepped shaft is inserted into the connecting splint assembly hole, and the concave groove is outside the connecting splint assembly hole. The connecting splint can rotate 360° along the connecting splint assembly hole, and then the valve plate is inserted into the concave groove of the connecting splint perpendicular to the valve seat, and the cylindrical pins are respectively inserted into the cylindrical pin hole I of the connecting splint and the cylindrical pin hole II of the valve plate from the outside of the left and right sides of the valve seat, so that the connecting splint and the valve plate are connected through the cylindrical pins and rotate synchronously, finally, gaskets and wire plugs are respectively installed in the radial sealing air on the left and right sides of the valve seat to complete the radial sealing of the check valve.

[0014] By adopting the above technical solution, the beneficial effects achieved by the utility model are as follows:

[0015] (1) The utility model realizes that when the centrifugal chiller is started, the valve plate rotates to open, and when it is stopped, the valve plate rotates to close by cooperating with the valve plate, connecting clamp, valve seat and horizontal limit structure. Combined with the metal plane sealing characteristics of the valve plate and the upper sealing chamber and the lower sealing chamber, the gas backflow is effectively blocked. The structure is simple, the cost is low, and it is easy to install and maintain.

[0016] (2) The check valve of the utility model has a short structure length, small volume and light weight, and is suitable for centrifugal chillers to reduce heat loss of centrifugal chillers.

[0017] (3) Since the connecting plate and the valve plate rotate synchronously during the opening and closing process of the check valve, it is necessary to perform radial sealing on the check valve. The radial sealing of the check valve is achieved through the cooperation of the gasket and the radial sealing hole. The structure is simple and easy to maintain. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a structural diagram of the utility model in a fully open state;

[0019] Figure 2 This is a schematic diagram of the structure of the utility model in a closed state;

[0020] Figure 3 It is a front view of the utility model in a fully open state;

[0021] Figure 4 for Figure 3 BB cross-sectional view;

[0022] Figure 5 for Figure 3 CC cross-sectional view;

[0023] Figure 6 This is a schematic structural diagram of the valve plate of the present utility model;

[0024] Figure 7 This is a schematic structural diagram of the connecting splint of the present invention.

[0025] In the figure, 1. valve seat; 2. valve plate; 3. connecting splint; 4. cylindrical pin; 5. screw plug; 6. upper sealing chamber; 7. lower sealing chamber; 9. horizontal limit structure I; 10. horizontal limit structure II; 11. concave groove; 12. stepped shaft; 13. cylindrical pin hole I; 14. cylindrical pin hole II; 15. countersunk hole; 16. connecting splint assembly hole; 17. radial sealing hole; 18. gasket. DETAILED DESCRIPTION

[0026] The present invention will be further described in detail below with reference to the accompanying drawings and specific implementation methods. Example

[0027] Reference Figure 1-7 In the present invention, a check valve with hard sealing characteristics includes a valve seat 1, a valve plate 2, a connecting splint 3, a cylindrical pin 4, a wire plug 5, an upper sealing chamber 6, a lower sealing chamber 7 and a horizontal limiting structure; the valve plate 2 is arranged inside the valve seat 1, the valve seat 1 and the valve plate 2 are connected by the connecting splint 3, the connecting splint 3 and the valve plate 2 are fixed by the cylindrical pin 4, an upper sealing chamber 6 is arranged on the upper part of the valve seat 1, a lower sealing chamber 7 is arranged on the lower part of the valve seat 1, the upper part of the valve plate 2 is sealed with the upper sealing chamber 6, the lower part of the valve plate 2 is sealed with the lower sealing chamber 7, a horizontal limiting structure is arranged in the middle part of the valve seat 1, and the horizontal limiting structure limits the rotation angle of the valve plate 2 to a maximum of 90°; a wire plug 5 is arranged on the outside of the connecting splint 3, and the wire plug 5 is arranged inside the valve seat 1.

[0028] The valve plate 2 of this embodiment 1 is oblong and made of aluminum bronze, which has good wear resistance and impact resistance. The valve seat 1 is an integral machined part.

[0029] Furthermore, the rotation center of the valve plate 2 is the center of the cylindrical pin 4 , and the rotation center of the valve plate 2 is set above the center line of the valve plate 2 , and the eccentricity ratio is 4 / 6, 4.5 / 5.5 or 3 / 7.

[0030] In this embodiment 1, the eccentricity ratio of the valve plate 2 is 4.5 / 5.5, the center of gravity of the valve plate 2 is below the rotation center, and the water hammer pressure is relatively small.

[0031] Furthermore, the upper sealing chamber 6 is arranged on the rear side of the valve plate 2, and the lower sealing chamber 7 is arranged on the front side of the valve plate 2. When the valve plate 2 is in a closed state, the rear end face of the valve plate 2 is in close contact with the upper sealing chamber 6, and the front end face of the valve plate 2 is in close contact with the lower sealing chamber 7.

[0032] Furthermore, the horizontal limiting structure includes a horizontal limiting structure I 9 and a horizontal limiting structure II 10. When the valve plate 2 rotates 90 degrees, the horizontal limiting structure I 9 contacts the front end surface of the valve plate 2, and the horizontal limiting structure II 10 contacts the rear end surface of the valve plate 2.

[0033] Through the cooperation of the upper sealing chamber 6, the lower sealing chamber 7, the horizontal limiting structure I 9 and the horizontal limiting structure II 10, when the check valve is switched from the closed state to the fully open state, the valve plate 2 can only rotate counterclockwise from 0° to 90°. When the check valve is switched from the fully open state to the closed state, the valve plate 2 rotates clockwise by 90°. The metal plane sealing characteristics of the valve plate 2, the upper sealing chamber 6 and the lower sealing chamber 7 effectively prevent gas backflow.

[0034] Furthermore, the connecting plate 3 includes a concave groove 11, a stepped shaft 12, and a cylindrical pin hole I 13. The stepped shaft 12 is connected to the rear end of the concave groove 11. The valve plate 2 is mounted in the concave groove 11, and the stepped shaft 12 is mounted in the valve seat 1. The cylindrical pin hole I 13 extends along the axis of the stepped shaft 12 to the concave groove 11. Cylindrical pin holes II 14 are symmetrically provided on the left and right ends of the valve plate 2. The cylindrical pin 4 is mounted in the cylindrical pin holes I 13 and II 14. The cylindrical pin 4 has an interference fit with the cylindrical pin holes I 13 and II 14. The concave groove 11 facilitates the installation and centering of the valve plate 2, and the stepped shaft 12 facilitates the rotation of the connecting plate 3 within the connecting plate assembly hole 16.

[0035] Furthermore, a countersunk hole 15 is provided at the rear end of the cylindrical pin hole 113, and a screw hole is provided at the top of the cylindrical pin 4. The countersunk hole 15 is convenient for inserting the cylindrical pin 4, and the screw hole is convenient for disassembling the cylindrical pin 4.

[0036] Furthermore, connecting plate assembly holes 16 are symmetrically arranged on the left and right sides of the inner wall of the valve seat 1, radial sealing holes 17 are arranged on the outside of the connecting plate assembly holes 16, the stepped shaft 12 of the connecting plate 3 is installed in the connecting plate assembly hole 16, and the screw plug 5 is installed in the radial sealing hole 17.

[0037] Furthermore, a gasket 18 is provided between the plug 5 and the connecting splint 3, and the gasket 18 is provided in the radial sealing hole 17. Through the cooperation of the gasket 18 and the radial sealing hole 17, radial sealing of the check valve is achieved.

[0038] The working principle of a check valve with hard sealing characteristics of the present invention is as follows: the initial state of the check valve is the closed state. When the centrifugal chiller is started, the refrigerant gas discharged from the compressor generates an instantaneous impact force, causing the valve plate 2 to rotate counterclockwise to open and find a balanced state or fully open in the refrigerant gas fluid. When the valve plate 2 is in the fully open state, the valve plate 2 rotates 90°. At this time, the front end surface of the valve plate 2 contacts the horizontal limit structure I 9, and the rear end surface of the valve plate 2 contacts the horizontal limit structure II 10, thereby limiting the valve plate 2 and preventing the valve plate 2 from rotating at an angle exceeding 90 degrees. When the centrifugal chiller is shut down, the refrigerant gas flows from the condenser to the compressor, and the gas backflow generates an instantaneous impact force. Combined with the gravity of the valve plate 2 itself, the valve plate 2 rotates clockwise and closes. At this time, the valve plate 2 is in close contact with the upper sealing cavity 6 and the lower sealing cavity 7. The elastic deformation of the aluminum bronze material of the valve plate 2 and the contact sealing effect of the valve plate 2 and the valve seat 1 surface form an effective seal, blocking the backflow gas, preventing the refrigerant gas from blowing directly to the impeller, and reducing fatigue damage to the impeller.

[0039] Since each additional check valve adds one resistance point to a centrifugal chiller, increases pressure loss by 0.1 bar, and causes approximately 1°C of heat loss at the compressor exhaust port, check valves installed in centrifugal chillers should be as lightweight and shaped to meet flow characteristics as possible while meeting strength, rigidity, and performance requirements. The check valve of Example 1 is short, compact, lightweight, and easy to manufacture and install, making it suitable for use in centrifugal chillers. It offers a cost-effective solution to the problem of effective backflow prevention in check valves and the difficulty of replacing damaged parts.

[0040] During installation of this embodiment 1, the connecting splint 3 is inserted into the connecting splint assembly hole 16 from the inside of the valve seat 1, so that the stepped shaft 12 is inserted into the connecting splint assembly hole 16, and the concave groove 11 is outside the connecting splint assembly hole 16. The connecting splint 3 can rotate 360° along the connecting splint assembly hole 16, and then the valve plate 2 is inserted into the concave groove 11 of the connecting splint 3 perpendicular to the valve seat 1, and the cylindrical pin 4 is respectively inserted into the cylindrical pin hole I 13 of the connecting splint 3 and the cylindrical pin hole II 14 of the valve plate 2 from the outside of the left and right sides of the valve seat 1, so that the connecting splint 3 and the valve plate 2 are connected through the cylindrical pin 4 and rotate synchronously, and finally, the gasket 18 and the wire plug 5 are respectively installed in the radial sealing holes 17 on the left and right sides of the valve seat 1 to complete the radial sealing of the check valve.

Claims

1. A check valve with hard sealing characteristics, characterized by: The valve seat (1) comprises a valve plate (2), a connecting splint (3), a cylindrical pin (4), a screw plug (5), an upper sealing cavity (6), a lower sealing cavity (7) and a horizontal limiting structure; the valve plate (2) is arranged inside the valve seat (1), the valve seat (1) and the valve plate (2) are connected by the connecting splint (3), the connecting splint (3) and the valve plate (2) are fixed by the cylindrical pin (4), an upper sealing cavity (6) is arranged on the upper part of the valve seat (1), a lower sealing cavity (7) is arranged on the lower part of the valve seat (1), the upper part of the valve plate (2) cooperates with the upper sealing cavity (6) to seal, the lower part of the valve plate (2) cooperates with the lower sealing cavity (7) to seal, a horizontal limiting structure is arranged in the middle of the valve seat (1), and the horizontal limiting structure limits the maximum rotation angle of the valve plate (2) to 90°; a screw plug (5) is arranged on the outer side of the connecting splint (3), and the screw plug (5) is arranged inside the valve seat (1).

2. A check valve with hard sealing characteristics according to claim 1, characterized in that: The rotation center of the valve plate (2) is the center of the cylindrical pin (4), and the rotation center of the valve plate (2) is arranged above the center line of the valve plate (2), and the eccentricity ratio is 4 / 6, 4.5 / 5.5 or 3 / 7.

3. The check valve with hard sealing characteristics according to claim 1, characterized in that: The upper sealing chamber (6) is arranged on the rear side of the valve plate (2), and the lower sealing chamber (7) is arranged on the front side of the valve plate (2). When the valve plate (2) is in a closed state, the rear end surface of the valve plate (2) is in close contact with the upper sealing chamber (6), and the front end surface of the valve plate (2) is in close contact with the lower sealing chamber (7).

4. A check valve with hard sealing properties according to claim 1, characterized in that: The horizontal limiting structure comprises a horizontal limiting structure I (9) and a horizontal limiting structure II (10). When the valve plate (2) rotates 90 degrees, the horizontal limiting structure I (9) contacts the front end surface of the valve plate (2), and the horizontal limiting structure II (10) contacts the rear end surface of the valve plate (2).

5. The check valve with hard sealing characteristics according to claim 1, characterized in that: The connecting splint (3) includes a concave groove (11), a stepped shaft (12) and a cylindrical pin hole I (13), the stepped shaft (12) is connected to the rear end of the concave groove (11), the valve plate (2) is installed in the concave groove (11), the stepped shaft (12) is installed in the valve seat (1), the cylindrical pin hole I (13) passes through the stepped shaft (12) along the axis to the concave groove (11), the cylindrical pin holes II (14) are symmetrically arranged at the left and right ends of the valve plate (2), the cylindrical pin (4) is installed in the cylindrical pin hole I (13) and the cylindrical pin hole II (14), and the cylindrical pin (4) is interference fit with the cylindrical pin hole I (13) and the cylindrical pin hole II (14).

6. A check valve with hard sealing properties according to claim 5, characterized in that: A countersunk hole (15) is provided at the rear end of the cylindrical pin hole I (13), and a screw hole is provided at the top of the cylindrical pin (4).

7. The check valve with hard sealing characteristics according to claim 5, characterized in that: Connecting plate assembly holes (16) are symmetrically provided on the left and right sides of the inner wall of the valve seat (1), radial sealing holes (17) are provided outside the connecting plate assembly holes (16), the stepped shaft (12) of the connecting plate (3) is installed in the connecting plate assembly hole (16), and the screw plug (5) is installed in the radial sealing hole (17).

8. The check valve with hard sealing characteristics according to claim 1, characterized in that: A gasket (18) is provided between the thread plug (5) and the connecting splint (3), and the gasket (18) is provided in the radial sealing hole (17).

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