Double-seal stop valve

Abstract

The utility model discloses a double-seal stop valve which comprises a valve body, a valve cover, a valve rod, a valve clack and a valve seat, a middle cavity is arranged in the valve body, an inlet flow channel and an outlet flow channel are respectively arranged at two ends of the valve body, the valve cover is installed at the upper end of the valve body, the valve rod is connected with the valve clack, and the valve seat is installed in the middle cavity and used for being in sealing fit with the valve clack when the valve is closed. An upper conical sealing face is arranged on the valve clack, a valve clack annular surfacing layer is arranged on the periphery of the upper conical sealing face, an upper valve seat annular surfacing layer and a lower valve seat annular surfacing layer which protrude out of the inner side of the valve seat are arranged on the valve seat, and when the valve is closed, the upper valve seat annular surfacing layer and the lower valve seat annular surfacing layer abut against the valve clack annular surfacing layer at the same time. And an upper conical surface sealing pair and a lower conical surface sealing pair are formed. The valve clack and the valve seat are matched through the two conical surface sealing pairs, the friction force is small, the service life is long, when one conical surface sealing pair is damaged, the other conical surface sealing pair can still achieve the sealing effect, and sealing is quite reliable.

Description

Technical Field

[0001] The utility model relates to the technical field of valves, in particular to a double-sealed stop valve. Background Art

[0002] The closing principle of the stop valve is to rely on the axial pressure of the valve stem to make the valve disc sealing surface fit tightly with the valve seat sealing surface to prevent the medium from flowing from bottom to top. However, this structure is a forced sealing structure, so when the valve is closed, pressure must be applied to the valve disc to force the sealing surface to prevent leakage.

[0003] Currently, the valve seat of a globe valve has only one sealing surface that acts as a seal. When the valve is closed, the pressure differential of the medium is concentrated on the sealing surface. Therefore, the medium exerts a large scouring force on the valve seat sealing surface, thereby accelerating the wear of the valve seat sealing surface and reducing its service life. Patent application number CN201811424419.4 discloses a double-seal globe valve, whose valve seat includes a valve seat cone and a valve seat ring arranged along the direction of valve disc movement. Its valve disc includes a valve disc cone and a valve disc ring arranged along the direction of valve disc movement. The valve seat cone and the valve disc cone cooperate to form a cone sealing pair, and the valve seat ring and the valve disc ring cooperate to form an annular sealing pair, realizing a double sealing structure. However, during the opening and closing process, this sealing structure experiences a large friction between the valve seat ring and the valve disc ring. Not only does this sealing structure have a large opening and closing operating torque, but the annular sealing pair is also extremely susceptible to wear and has a short service life. Therefore, this structure needs to be improved. Utility Model Content

[0004] The purpose of the utility model is to provide a double-seal stop valve. The valve disc and the valve seat of the utility model are matched in the form of two conical sealing pairs, which not only has low friction and long service life, but also when one conical sealing pair is damaged, the other conical sealing pair can still play a sealing effect, and the sealing is very reliable.

[0005] To achieve the above-mentioned purpose, the utility model provides the following technical solution: a double-sealed stop valve, comprising a valve body, a valve cover, a valve stem, a valve disc and a valve seat, wherein a middle cavity is provided in the valve body, and an inlet flow channel and an outlet flow channel are respectively provided at two ends of the valve body and connected to the middle cavity, the valve cover is installed at the upper end of the valve body, the valve stem passes through the valve cover and is linked to the valve disc arranged in the middle cavity of the valve body, and the valve seat is installed in the middle cavity to form a sealing cooperation with the valve disc when the valve is closed; the valve disc is provided with an upper conical sealing surface, the outer periphery of the upper conical sealing surface is provided with a valve disc annular surfacing layer, and the valve seat is provided with an upper valve seat annular surfacing layer and a lower valve seat annular surfacing layer protruding from the inner side of the valve seat. When the valve is closed, the upper valve seat annular surfacing layer and the lower valve seat annular surfacing layer simultaneously abut against the valve disc annular surfacing layer to form an upper conical surface sealing pair and a lower conical surface sealing pair, and an annular cavity is formed between the upper conical surface sealing pair and the lower conical surface sealing pair.

[0006] By adopting the above technical solution, the valve disc and the valve seat are matched with two conical sealing pairs, which not only has low friction and long service life, but also when one conical sealing pair is damaged, the other conical sealing pair can still achieve a sealing effect, and the sealing is very reliable.

[0007] The utility model is further configured such that the upper inner end of the valve seat is provided with a lower conical sealing surface adapted to the upper conical sealing surface on the valve disc, and the upper valve seat annular surfacing layer and the lower valve seat annular surfacing layer are respectively provided at the upper edge and the lower edge of the lower conical sealing surface.

[0008] By adopting the above technical solution, it is the first structure of the valve seat.

[0009] The utility model is further configured such that a sealing flange extending toward the inner periphery is provided at the lower end of the valve seat, and the upper valve seat annular surfacing layer and the lower valve seat annular surfacing layer are respectively provided at the inner edge of the upper end of the valve seat and the inner edge of the upper end of the sealing flange.

[0010] By adopting the above technical solution, it is the second structure of the valve seat.

[0011] The utility model is further configured such that an annular partition is provided in the middle of the annular surfacing layer of the valve disc, and an annular expansion opening is provided at the outer end of the annular partition, which is larger on the outside and smaller on the inside and is communicated with the annular cavity.

[0012] By adopting the above technical solution, the cavity between the upper cone sealing pair and the lower cone sealing pair has more corners, and the medium flowing through this position has a flushing effect when the valve is opened and closed, and has a self-cleaning function.

[0013] The utility model is further configured such that a mounting groove is provided on the valve body at a position corresponding to the inner wall of the middle cavity, the valve seat is embedded in the mounting groove, and a sealing gasket is provided between the valve seat and the mounting groove.

[0014] By adopting the above technical solution, the valve seat is not only easy to install but also has good sealing performance.

[0015] The present invention is further configured such that a sleeve is further provided in the middle cavity, a plurality of throttling holes are evenly provided on the side of the sleeve, the sleeve is sleeved on the outer periphery of the valve disc and the two are clearance-matched.

[0016] By adopting the above technical solution, the provision of a sleeve can achieve a decompression effect, which can not only improve the turbulent state of the medium and prevent the occurrence of water hammer, but also reduce the valve opening and closing torque, making the valve opening and closing easier, and can also reduce the scouring effect on the two conical sealing pairs, thereby increasing their service life.

[0017] The utility model is further configured to include a self-sealing component, which includes a packing pressure plate, a packing sleeve, a sealing packing, a valve core, a self-tightening gasket and a gasket; the upper end of the valve body is provided with a supporting step, the valve core is arranged on the supporting step, the inner side of the upper end of the valve core is provided with a first sealing groove, the packing pressure plate is connected to the valve cover through a fastener, and the packing pressure plate is pressed against the upper end of the packing sleeve to prompt the packing sleeve to press the sealing packing into the sealing groove; the inner side of the upper end of the valve core is provided with a second sealing groove, the lower end of the valve cover is provided with a clamping flange, the clamping flange is threadedly connected to the inner side of the upper end of the valve body and pressed against the upper end of the gasket, prompting the gasket to press the self-tightening gasket into the second sealing groove, and the upper end of the second sealing groove is provided with a first sealing cone surface, and the lower end of the self-tightening gasket is provided with a second sealing cone surface matching the first sealing cone surface.

[0018] By adopting the above technical solution, good sealing between the valve cover and the valve body and between the valve cover and the valve stem can be ensured, and the internal medium can be prevented from leaking from the gap between the valve cover and the valve body or between the valve cover and the valve stem.

[0019] The present invention is further configured such that a locking nut is threadedly connected to the outer periphery of the valve core, and the locking nut is tightly pressed against the upper end of the valve cover.

[0020] By adopting the above technical solution, the locking nut presses against the valve cover, which can enhance the thread friction between the clamping flange and the inner wall of the valve body, thereby preventing the valve cover from loosening and ensuring the reliability of the sealing structure.

[0021] The utility model is further configured such that the lower end of the valve core is tightly pressed against the upper end of the sleeve, so that the sleeve presses the valve seat tightly against the installation groove.

[0022] By adopting the above technical solution, the sleeve and the valve seat can be positioned and installed by installing the self-sealing component, and the assembly operation is very convenient.

[0023] An inverted T-shaped connecting portion is provided at the lower end of the valve stem, and an inverted T-shaped connecting groove which matches the inverted T-shaped connecting portion is opened at the side of the upper end of the valve disc.

[0024] By adopting the above technical solution, the connection structure between the two is simple and reliable, and the assembly and disassembly is very convenient. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 It is a structural diagram of the utility model;

[0026] Figure 2 for Figure 1 A schematic diagram of the enlarged structure of the middle part A;

[0027] Figure 3 This is a schematic diagram of the first structure of the valve seat of the utility model;

[0028] Figure 4 This is a schematic diagram of the second structure of the valve seat of the utility model;

[0029] Figure 5 for Figure 1 Schematic diagram of the enlarged structure of part B in the middle.

[0030] In the figure: 1. Valve body; 2. Valve cover; 3. Valve stem; 4. Valve disc; 5. Valve seat; 6. Center cavity; 7. Inlet flow channel; 8. Outlet flow channel; 9. Upper conical sealing surface; 10. Annular weld overlay of valve disc; 11. Annular weld overlay of upper valve seat; 12. Annular weld overlay of lower valve seat; 13. Annular cavity; 14. Lower conical sealing surface; 15. Sealing flange; 16. Annular partition; 17. Annular flare; 18. Mounting groove; 19. Sealing gasket. 20. Sleeve; 21. Throttle hole; 22. Self-sealing assembly; 23. Packing pressure plate; 24. Packing sleeve; 25. Sealing packing; 26. Valve core; 27. Self-tightening gasket; 28. Spacer; 29. ​​Support step; 30. First sealing groove; 31. Second sealing groove; 32. Clamping flange; 33. First sealing cone surface; 34. Second sealing cone surface; 35. Locking nut; 36. Inverted T-shaped connecting part; 37. Inverted T-shaped connecting groove. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0032] Example: As shown in the attached Figures 1 to 5The double-seal stop valve shown in the figure includes a valve body 1, a valve cover 2, a valve stem 3, a valve disc 4 and a valve seat 5. The valve body 1 is provided with a central cavity 6, which extends vertically. The two ends of the valve body 1 are respectively provided with an inlet flow channel 7 and an outlet flow channel 8 connected to the side of the central cavity 6. The valve cover 2 is installed at the upper end of the valve body 1. The valve stem 3 passes through the valve cover 2 and is linked to the valve disc 4 provided in the central cavity 6 of the valve body 1. The valve seat 5 is installed in the central cavity 6 to form a sealing cooperation with the valve disc 4 when the valve is closed; the valve disc 4 is provided with an upper conical sealing surface 9, and the upper conical sealing surface 9 A valve disc annular surfacing layer 10 is provided on the outer periphery, and an upper valve seat annular surfacing layer 11 and a lower valve seat annular surfacing layer 12 protruding from the inner side of the valve seat 5 are provided on the valve seat 5. When the valve is closed, the upper valve seat annular surfacing layer 11 and the lower valve seat annular surfacing layer 12 are simultaneously pressed against the valve disc annular surfacing layer 10 to form an upper conical sealing pair and a lower conical sealing pair. An annular cavity 13 is formed between the upper conical sealing pair and the lower conical sealing pair. The contact area between the upper valve seat annular surfacing layer 11 and the lower valve seat annular surfacing layer 12 and the valve disc annular surfacing layer 10 is relatively small. The valve disc 4 and the valve seat 5 are matched in the form of two conical sealing pairs, which not only has low friction and long service life, but also when one conical sealing pair is damaged, the other conical sealing pair can still play a sealing effect, and the seal is very reliable. The annular cavity 13 formed between the upper conical sealing pair and the lower conical sealing pair has the function of a water seal, which not only has the effect of enhancing the sealing performance, but also can prevent gas from mixing into the liquid during the opening and closing process of the valve, effectively preventing cavitation.

[0033] The valve seat 5 has the following two structures:

[0034] The first structure of the valve seat 5: as shown in the attached Figure 3 As shown, the upper inner end of the valve seat 5 is provided with a lower conical sealing surface 14 that is compatible with the upper conical sealing surface 9 on the valve disc 4, and the upper valve seat annular surfacing layer 11 and the lower valve seat annular surfacing layer 12 are respectively arranged at the upper edge and the lower edge of the lower conical sealing surface 14.

[0035] The second structure of the valve seat 5: as shown in the attached Figure 4 As shown, the lower end of the valve seat 5 is provided with a sealing flange 15 extending toward the inner periphery, and the upper valve seat annular surfacing layer 11 and the lower valve seat annular surfacing layer 12 are respectively provided at the inner edge of the upper end of the valve seat 5 and the inner edge of the upper end of the sealing flange 15.

[0036] As attached Figure 2 As shown, an annular partition 16 is provided in the middle of the disc's annular overlay layer 10. An annular flare 17, which is larger on the outside and smaller on the inside and communicates with the annular cavity 13, is provided at the outer end of the annular partition 16. This design creates more corners in the cavity between the upper and lower conical sealing pairs. When the valve is opened and closed, the medium flowing through this area has a flushing effect, providing a self-cleaning function.

[0037] As attached Figure 2 As shown, the valve body 1 has a mounting groove 18 formed on the inner wall of the central cavity 6. The valve seat 5 is embedded in the mounting groove 18, and a sealing gasket 19 is provided between the valve seat 5 and the mounting groove 18. The sealing gasket 19 is made of an elastic material, such as silicone or rubber. The valve seat 5 is not only easy to install but also has good sealing performance.

[0038] As attached Figure 1 As shown, a sleeve 20 is further disposed within the central cavity 6. Multiple throttle holes 21 are evenly distributed on the sides of the sleeve 20. The throttle holes 21 connect the central cavity 6 with the inlet flow channel 7. The sleeve 20 is sleeved around the outer periphery of the valve disc 4, with the two discs being fitted together with a clearance. The provision of the sleeve 20 provides a decompression effect, improving the turbulent flow of the medium and preventing water hammer. It also reduces the valve opening and closing torque, making it easier to open and close the valve. It also reduces the scouring effect on the two conical sealing pairs, thereby increasing their service life.

[0039] As attached Figure 5 As shown, it also includes a self-sealing component 22, which includes a packing pressure plate 23, a packing sleeve 24, a sealing packing 25, a valve core 26, a self-tightening gasket 27 and a pad 28; the upper end of the valve body 1 is provided with a support step 29, the valve core 26 is arranged on the support step 29, and the inner side of the upper end of the valve core 26 is provided with a first sealing groove 30, the packing pressure plate 23 is connected to the valve cover 2 by a fastener, and the packing pressure plate 23 is pressed against the upper end of the packing sleeve 24 to cause the packing sleeve 24 to The sealing packing 25 is pressed tightly into the sealing groove; a second sealing groove 31 is provided on the inner side of the upper end of the valve core 26, and a pressing flange 32 is provided on the lower end of the valve cover 2. The pressing flange 32 is threadedly connected to the inner side of the upper end of the valve body 1 and presses against the upper end of the gasket 28, prompting the gasket 28 to press the self-tightening gasket 27 into the second sealing groove 31. The upper end of the second sealing groove 31 is provided with a first sealing cone 33, and the lower end of the self-tightening gasket 27 is provided with a second sealing cone 34 that cooperates with the first sealing cone 33. This design ensures good sealing between the valve cover 2 and the valve body 1, as well as between the valve cover 2 and the valve stem 3, and prevents internal media from leaking from the gaps between the valve cover 2 and the valve body 1 or between the valve cover 2 and the valve stem 3.

[0040] As attached Figure 5 As shown, a locking nut 35 is threadedly connected to the outer periphery of the valve core 26, and the locking nut 35 is tightly abutted against the upper end of the valve cover 2. The locking nut 35 abuts against the valve cover 2, which can enhance the thread friction between the pressing flange 32 and the inner wall of the valve body 1, thereby preventing the valve cover 2 from loosening and ensuring the reliability of the sealing structure.

[0041] As attached Figure 1 and attached Figure 5As shown, the lower end of the valve core 26 is tightly against the upper end of the sleeve 20, prompting the sleeve 20 to press the valve seat 5 against the installation groove 18. After the self-sealing component 22 is installed, the sleeve 20 and the valve seat 5 can be positioned and installed, and the assembly operation is very convenient.

[0042] As attached Figure 1 As shown, the lower end of the valve stem 3 is provided with an inverted T-shaped connecting portion 36, and the upper end side of the valve disc 4 is provided with an inverted T-shaped connecting groove 37 that fits with the inverted T-shaped connecting portion 36. The connection structure of the two is simple and reliable, and is very convenient to disassemble and assemble.

Claims

1. A double-sealed stop valve, comprising a valve body (1), a valve cover (2), a valve stem (3), a valve disc (4) and a valve seat (5), wherein a central cavity (6) is provided in the valve body (1), and an inlet flow channel (7) and an outlet flow channel (8) are respectively provided at both ends of the valve body (1) and communicate with the central cavity (6), wherein the valve cover (2) is mounted on the upper end of the valve body (1), the valve stem (3) passes through the valve cover (2) and is linked to the valve disc (4) disposed in the central cavity (6) of the valve body (1), and the valve seat (5) is mounted in the central cavity (6) to form a sealing fit with the valve disc (4) when the valve is closed; and characterized in that: The valve disc (4) is provided with an upper conical sealing surface (9), and a valve disc annular cladding layer (10) is provided on the outer periphery of the upper conical sealing surface (9). The valve seat (5) is provided with an upper valve seat annular cladding layer (11) and a lower valve seat annular cladding layer (12) protruding from the inner side of the valve seat (5). When the valve is closed, the upper valve seat annular cladding layer (11) and the lower valve seat annular cladding layer (12) simultaneously press against the valve disc annular cladding layer (10) to form an upper conical sealing pair and a lower conical sealing pair, and an annular cavity (13) is formed between the upper conical sealing pair and the lower conical sealing pair.

2. The double seal stop valve according to claim 1, characterized in that: The upper inner end of the valve seat (5) is provided with a lower conical sealing surface (14) adapted to the upper conical sealing surface (9) on the valve disc (4), and the upper valve seat annular surfacing layer (11) and the lower valve seat annular surfacing layer (12) are respectively provided at the upper edge and the lower edge of the lower conical sealing surface (14).

3. The double seal stop valve according to claim 1, characterized in that: The lower end of the valve seat (5) is provided with a sealing flange (15) extending toward the inner periphery, and the upper valve seat annular surfacing layer (11) and the lower valve seat annular surfacing layer (12) are respectively provided at the inner edge of the upper end of the valve seat (5) and the inner edge of the upper end of the sealing flange (15).

4. The double seal stop valve according to claim 1, characterized in that: An annular partition (16) is provided in the middle of the valve disc annular surfacing layer (10), and an annular expansion opening (17) is provided at the outer end of the annular partition (16), which is larger on the outside and smaller on the inside and is connected to the annular cavity (13).

5. The double seal stop valve according to claim 1, characterized in that: The valve body (1) is provided with a mounting groove (18) at a position corresponding to the inner wall of the middle cavity (6), the valve seat (5) is embedded in the mounting groove (18), and a sealing gasket (19) is provided between the valve seat (5) and the mounting groove (18).

6. The double seal stop valve according to claim 5, characterized in that: A sleeve (20) is further provided in the middle cavity (6), and a plurality of throttle holes (21) are evenly arranged on the side of the sleeve (20). The sleeve (20) is sleeved on the outer periphery of the valve disc (4) and the two are clearance-matched.

7. The double-seal stop valve according to claim 6, characterized in that: The valve body (1) further comprises a self-sealing assembly (22), wherein the self-sealing assembly (22) comprises a packing pressure plate (23), a packing pressure sleeve (24), a sealing packing (25), a valve core (26), a self-tightening gasket (27) and a gasket (28); a support step (29) is provided at the upper end of the valve body (1), the valve core (26) is arranged on the support step (29), a first sealing groove (30) is provided on the inner side of the upper end of the valve core (26), the packing pressure plate (23) is connected to the valve cover (2) through a fastener, and the packing pressure plate (23) is pressed against the upper end of the packing pressure sleeve (24) to cause the packing pressure sleeve (24) to be pressed. ) presses the sealing packing (25) into the sealing groove; a second sealing groove (31) is provided on the inner side of the upper end of the valve core (26), and a clamping flange (32) is provided on the lower end of the valve cover (2), and the clamping flange (32) is threadedly connected to the inner side of the upper end of the valve body (1) and pressed against the upper end of the gasket (28), so that the gasket (28) presses the self-tightening gasket (27) into the second sealing groove (31), and a first sealing cone surface (33) is provided on the upper end of the second sealing groove (31), and a second sealing cone surface (34) is provided on the lower end of the self-tightening gasket (27) to match the first sealing cone surface (33).

8. The double seal stop valve according to claim 7, characterized in that: The outer periphery of the valve core (26) is also threadedly connected with a locking nut (35), and the locking nut (35) is tightly abutted against the upper end of the valve cover (2).

9. The double-seal stop valve according to claim 7, characterized in that: The lower end of the valve core (26) is tightly pressed against the upper end of the sleeve (20), prompting the sleeve (20) to press the valve seat (5) onto the installation groove (18).

10. The double seal stop valve according to claim 1, characterized in that: The lower end of the valve stem (3) is provided with an inverted T-shaped connecting portion (36), and the upper end side of the valve flap (4) is provided with an inverted T-shaped connecting groove (37) that fits with the inverted T-shaped connecting portion (36).

Images