Connector sealing structure of power station valve

Abstract

The utility model discloses an interface sealing structure of a power station valve, belongs to the technical field of valve sealing, and aims to solve the problem that a metal winding gasket between the power station valve and a connecting pipeline easily causes relatively large abrasion to a connecting bolt between flange plates during long-term sealing work. The sealing structure comprises a metal winding gasket, an annular sealing gasket and two sealing connection semi-rings, the annular sealing gasket comprises an outer ring part and an inner ring part, the outer ring part coaxially sleeves the inner ring part, the inner ring part is arranged between a valve flange plate and a pipeline flange plate, the inner ring part sleeves the metal winding gasket, and the two sealing connection semi-rings are arranged on the metal winding gasket. The inner ring part is clamped and fixed with a pipeline flange plate through a valve flange plate, the outer ring part is arranged on the outer circle face of the valve flange plate and the outer circle face of the pipeline flange plate in a sleeving mode, and the two sealing connection semi-rings are clamped on the outer ring wall of the outer ring part and detachably connected through a bolt and nut assembly. The sealing structure is mainly used at the joint of the power station valve and the pipeline.

Description

Technical Field

[0001] This utility model belongs to the field of valve sealing technology, specifically relating to an interface sealing structure for a power station valve. Background Technology

[0002] Power plant valves are large valves used in high-temperature and high-pressure conditions. Ensuring the sealing of the interface between the valve and the connecting pipeline is crucial during operation. Any pressure leakage in the connecting pipeline can not only affect the stable operation of the entire power plant but also easily lead to safety accidents. Currently, power plant valves and pipelines are mostly connected using flange structures, with the sealing structure typically being a spiral wound gasket. The spiral wound layer between the two metal rings in the gasket can undergo certain deformation under high temperature and pressure to adapt to the special operating conditions of the power plant valve. However, most existing power plant valve flanges are flat flanges. When installing the spiral wound gasket, the flange connecting bolts are required as a positioning structure. The specific process is as follows: first, bring the valve flange close to the pipeline flange, insert half of the bolts into the connecting hole between the two flanges, then insert the spiral wound gasket through the gap between the valve flange and the pipeline flange, and finally, use the bolts to contact the outer wall of the gasket to ensure proper sealing. After the position of the spiral wound gasket is determined, the two valve flanges are closed and tightened with bolts. Although the spiral wound layer in the spiral wound gasket can well adapt to some of the gasket deformation caused by radial force, there are still some problems with using the spiral wound gasket as the sealing structure alone in actual use. Under the influence of high temperature and high pressure working environment, the spiral wound gasket will still expand outward as a whole, causing extrusion wear on the bolts between the valve flange and the pipe flange. Long-term service will cause bolt deformation and shorten bolt life. This means that the degree of extrusion wear on the bolts needs to be monitored during each maintenance, and some bolts with large extrusion deformation need to be replaced, indirectly increasing the cost of maintenance. Therefore, in order to overcome the problem that the spiral wound gasket can easily cause great wear on the connecting bolts between the flanges during long-term sealing operation, it is very much in line with the actual needs to develop a combined interface sealing structure for power plant valves. Utility Model Content

[0003] This utility model aims to solve the problem that metal spiral wound gaskets between power plant valves and connecting pipes can easily cause significant wear to the connecting bolts between flanges during long-term sealing operation, and thus provides an interface sealing structure for power plant valves.

[0004] A sealing structure for the interface of a power plant valve includes a spiral wound gasket. The spiral wound gasket is disposed between the valve flange on the power plant valve and the pipe flange on the corresponding connecting pipe. The spiral wound gasket is clamped and fixed by the valve flange and the pipe flange and is used to seal the interface between the power plant valve and the connecting pipe.

[0005] The sealing structure also includes an annular sealing gasket and two sealing connection half-rings. The annular sealing gasket includes an outer ring and an inner ring. The outer ring is coaxially sleeved on the outside of the inner ring, and the outer ring wall of the inner ring is integrally formed with the center of the inner ring wall in the outer ring. The inner ring is located between the valve flange and the pipe flange and is sleeved on the metal spiral wound gasket. The inner ring is clamped and fixed by the valve flange and the pipe flange. The outer ring is sleeved on the outer circular surface of the valve flange and the pipe flange. The two sealing connection half-rings are clamped on the outer ring wall of the outer ring and are detachably connected by a bolt and nut assembly.

[0006] Furthermore, one end of the outer ring extends to the outer end face of the valve flange and is coplanar with the outer end face of the valve flange, and the other end of the outer ring extends to the outer end face of the pipe flange and is coplanar with the outer end face of the pipe flange.

[0007] Furthermore, the end of the inner ring is machined with multiple through holes at equal intervals along the circumference, and each through hole is coaxially corresponding to a connecting bolt between a valve flange and a pipe flange;

[0008] Furthermore, N sealing ring grooves are machined on the end faces of both ends of the inner ring, where N is a positive integer, and all N sealing ring grooves are located between the through hole and the inner ring wall of the inner ring. A sealing ring is embedded in each sealing ring groove, and the two ends of the inner ring are in close contact with the valve flange or pipe flange through the sealing ring.

[0009] Furthermore, the width of the sealing connection half-ring is the same as the width of the outer ring;

[0010] Furthermore, each end of the sealing connection half ring is provided with a connecting lug plate, and the top of each connecting lug plate is machined with a vertically downward extending connecting through hole. The two sealing connection half rings are disassembled and connected by the cooperation of the connecting lug plate and the bolt and nut assembly.

[0011] Furthermore, each end face of the sealing connection half ring is provided with two clamps, and each clamp is set between two adjacent connecting bolts on the valve flange and the pipe flange. One end of each clamp is detachably connected to the end face of the sealing connection half ring by bolts, and the other end of each clamp extends to the outer end face of the valve flange or the outer end face of the pipe flange, and the inner side of the other end of each clamp is in close contact with the outer end face of the valve flange or the outer end face of the pipe flange.

[0012] Furthermore, a gasket is provided on the inner side of the other end of each clamp, and each clamp is in close contact with the outer end face of the valve flange or the outer end face of the pipe flange through the gasket;

[0013] The beneficial effects of this application compared to the prior art are:

[0014] This application provides an interface sealing structure for a power plant valve. Based on a traditional spiral wound gasket, an annular sealing gasket and two sealing half-rings are added. The annular sealing gasket is fitted onto both the valve flange and the pipe flange, and simultaneously also fits over the spiral wound gasket. The through-hole inside the annular sealing gasket can replace the connecting bolts for installation and positioning of the spiral wound gasket. The annular sealing gasket also protects the connecting bolts, effectively preventing rigid contact between the spiral wound gasket and the connecting bolts. Even if the spiral wound gasket expands during operation, the annular sealing gasket prevents direct compression of the connecting bolts, reducing bolt wear and deformation, effectively improving bolt lifespan, and reducing maintenance time and costs.

[0015] During the installation of the annular sealing gasket, the sealing ring structure composed of sealing connecting half rings is used for clamping and fixing, ensuring the stability of the annular sealing gasket during operation. In addition to positioning the metal spiral wound gasket during installation and avoiding rigid compression between the connecting bolts and the metal spiral wound gasket, the annular sealing gasket can also help to further improve the connection sealing between the valve flange and the pipe flange, effectively reducing the possibility of interface pressure relief and interface leakage during the operation of power plant valves. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the installation of the interface sealing structure described in this application;

[0017] Figure 2 This is a schematic diagram of the interface sealing structure described in this application;

[0018] Figure 3 This is a side view of the interface sealing structure described in this application after installation;

[0019] Figure 4 This is a schematic diagram of the annular sealing gasket in the interface sealing structure described in this application;

[0020] Figure 5 This is a cross-sectional view along direction aa of the annular sealing gasket in the interface sealing structure described in this application;

[0021] Figure 6 This is a schematic diagram of the annular sealing gasket in the interface sealing structure described in this application (when the sealing ring is installed);

[0022] Figure 7 This is a cross-sectional view along the bb direction of the annular sealing gasket in the interface sealing structure described in this application (when the sealing ring is installed);

[0023] Figure 8 for Figure 7 A magnified view of a section at point A in the middle;

[0024] Figure 9 for Figure 6 A magnified view of a section at point B in the middle;

[0025] Figure 10 This is a schematic diagram of the installation of the interface sealing structure described in this application (when installing the clamping plate);

[0026] Figure 11 This is a side view of the interface sealing structure described in this application after installation (when the clamping plate is installed);

[0027] In the figure, 1 is a metal spiral wound gasket, 2 is an annular sealing gasket, 21 is an outer ring, 22 is an inner ring, 221 is a through hole, 222 is a sealing ring groove, 223 is a sealing ring, 3 is a sealing connection half ring, 31 is a rubber gasket, 32 is a clamping plate, 33 is a gasket, 4 is a power station valve, 41 is a valve flange, 5 is a connecting pipe, and 51 is a pipe flange. Detailed Implementation

[0028] Specific implementation method one: Combining Figures 1 to 11 This embodiment describes a sealing structure for the interface of a power station valve. The sealing structure includes a spiral wound gasket 1, which is disposed between the valve flange 41 on the power station valve 4 and the pipe flange 51 on the corresponding connecting pipe 5. The spiral wound gasket 1 is clamped and fixed by the valve flange 41 and the pipe flange 51 and is used to seal the interface between the power station valve 4 and the connecting pipe 5.

[0029] The sealing structure also includes an annular sealing gasket 2 and two sealing connection half-rings 3. The annular sealing gasket 2 includes an outer ring portion 21 and an inner ring portion 22. The outer ring portion 21 is coaxially sleeved on the outside of the inner ring portion 22, and the outer ring wall of the inner ring portion 22 is integrally formed with the center of the inner ring wall in the outer ring portion 21. The inner ring portion 22 is disposed between the valve flange 41 and the pipe flange 51, and the inner ring portion 22 is sleeved on the metal spiral wound gasket 1. The inner ring portion 22 is clamped and fixed by the valve flange 41 and the pipe flange 51. The outer ring portion 21 is sleeved on the outer circular surface of the valve flange 41 and the pipe flange 51. The two sealing connection half-rings 3 are clamped on the outer ring wall of the outer ring portion 21, and the two sealing connection half-rings 3 are detachably connected by a bolt and nut assembly.

[0030] This embodiment describes a sealing structure for the interface of a power plant valve. It employs a combination of annular sealing gasket 2 and spiral wound gasket 1 to ensure the sealing stability between the valve flange 41 and the pipe flange 51. The inner spiral wound layer of the spiral wound gasket 1 is made of graphene, while the annular sealing gasket 2 is made of silicone rubber or fluororubber. The outer ring 21 of the annular sealing gasket 2 wraps around the outer surfaces of the valve flange 41 and the pipe flange 51, achieving circumferential sealing under the clamping and compression of the annular structure formed by two sealing connecting half-rings 3. This also avoids rigid contact between the sealing connecting half-rings 3 and the outer surface of the flange, preventing wear on the flange. The inner ring 22 works with the spiral wound gasket 1 to further improve the sealing performance between the valve flange 41 and the pipe flange 51. Simultaneously, the inner ring 22 effectively positions the spiral wound gasket 1 during installation, preventing rigid compression between it and the connecting bolts between the valve flange 41 and the pipe flange 51, thus improving the service life of the connecting bolts.

[0031] Specific Implementation Method Two: Combining Figures 1 to 11 This embodiment differs from Specific Embodiment 1 in that one end of the outer ring 21 extends to the outer end face of the valve flange 41 and is coplanar with the outer end face of the valve flange 41, while the other end of the outer ring 21 extends to the outer end face of the pipe flange 51 and is coplanar with the outer end face of the pipe flange 51. Other components and connection methods are the same as in Specific Embodiment 1.

[0032] Specific implementation method three: Combining Figures 1 to 11 This embodiment differs from Specific Embodiment Two in that the end of the inner ring 22 has multiple through holes 221 machined at equal intervals along the circumference, and each through hole 221 is coaxially corresponding to a connecting bolt between a valve flange 41 and a pipe flange 51. Other components and connection methods are the same as in Specific Embodiment Two.

[0033] Specific implementation method four: Combination Figures 1 to 11 This embodiment differs from Specific Embodiment Three in that N sealing ring grooves 222 are machined on the end faces of both ends of the inner ring portion 22, where N is a positive integer. All N sealing ring grooves 222 are located between the through hole 221 and the inner ring wall of the inner ring portion 22. A sealing ring 223 is embedded in each sealing ring groove 222. Both ends of the inner ring portion 22 are in close contact with the valve flange 41 or pipe flange 51 through the sealing rings 223. Other components and connection methods are the same as in Specific Embodiment Three.

[0034] Referring to specific embodiments two to four, the through hole 221 is used to mate with the connecting bolts between the valve flange 41 and the pipe flange 51 to avoid connection interference. The design of the sealing ring groove 222 and the sealing ring 223 is to improve the tightness of the connection between the annular sealing gasket 2 and the valve flange 41 and the pipe flange 51. When the metal spiral wound gasket 1 expands outward as a whole during operation, the outer metal ring of the metal spiral wound gasket 1 will be squeezed against the inner wall of the inner ring 22, and the resulting radial force will be gradually diffused outward to the sealing ring 223. Under the compression of the circumferential clamping force and the radial force, the sealing ring 223 will fit tightly with the inner ring 22, the valve flange 41 and the pipe flange 51, thereby helping to provide the sealing stability of the sealing structure.

[0035] Specific Implementation Method Five: Combining Figures 1 to 11 This embodiment differs from Specific Embodiment Four in that the width of the sealing connection half-ring 3 is the same as the width of the outer ring portion 21. Other components and connection methods are the same as in Specific Embodiment Four.

[0036] Specific Implementation Method Six: Combination Figures 1 to 11 This embodiment differs from specific embodiment five in that each end of the sealing connection half-ring 3 is provided with a connecting lug plate. Each connecting lug plate has a vertically downward-extending connecting through hole machined at its top. The two sealing connection half-rings 3 are connected and detached through the cooperation of the connecting lug plates and the bolt and nut assembly. Other components and connection methods are the same as in specific embodiment five.

[0037] Specific implementation method seven: Combination Figures 1 to 11 This embodiment differs from Specific Embodiment Six in that each end face of the sealing connection half-ring 3 is further provided with two clamping plates 32. Each clamping plate 32 is positioned between two adjacent connecting bolts on the valve flange 41 and the pipe flange 51. One end of each clamping plate 32 is detachably connected to the end face of the sealing connection half-ring 3 by bolts, and the other end of each clamping plate 32 extends to the outer end face of the valve flange 41 or the pipe flange 51, with the inner side of the other end of each clamping plate 32 in close contact with the outer end face of the valve flange 41 or the pipe flange 51. Other components and connection methods are the same as in Specific Embodiment Six.

[0038] Specific implementation method eight: Combination Figures 1 to 11 This embodiment differs from specific embodiment seven in that a gasket 33 is provided on the inner side of the other end of each clamping plate 32, and each clamping plate 32 is in close contact with the outer end face of the valve flange 41 or the outer end face of the pipe flange 51 through the gasket 33. Other components and connection methods are the same as in specific embodiment seven.

[0039] Referring to specific embodiments five to eight, a rubber gasket 31 is provided between the two connecting lugs on the same side of the two sealing connection half-rings 3. The rubber gasket 31 serves as a connection protection, preventing rigid contact between the two connecting lugs. The clamping plate 32 is designed to further increase the axial clamping force between the valve flange 41 and the pipe flange 51, preventing axial clearance between the valve flange 41 and the pipe flange 51 during operation. The axial clearance mentioned here refers to a special case where the internal winding layer of the metal spiral wound gasket 1 fails due to breakage during operation, which can easily lead to... The inner metal ring of the metal spiral wound gasket 1 undergoes axial deformation. When the sealing is achieved solely by the metal spiral wound gasket 1, the spiral wound layer fails. The axial deformation of the inner metal ring increases the probability of axial clearance, thereby increasing the possibility of pressure relief and leakage. By using the clamp 32 at the end of the flange, the connection tightness between the valve flange 41 and the pipe flange 51 can be improved, and the generation of axial clearance can be constrained to the greatest extent. In order to avoid damaging the flange surface when the clamp 32 contacts the flange, a thin gasket 33 is provided between the clamp 32 and the flange. The thin gasket 33 is a soft metal gasket, such as a thin copper sheet.

[0040] The present invention has been disclosed above with reference to preferred embodiments, but it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed structure and technical content to create equivalent embodiments without departing from the scope of the present invention. However, any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

[0041] Working principle

[0042] In this application, the annular sealing gasket 2 is first fitted onto the outer circumference of the valve flange 41, ensuring that the inner ring portion 22 of the annular sealing gasket 2 is tightly against the end face of the connecting end of the valve flange 41. Simultaneously, each through hole 221 on the inner ring portion 22 corresponds to a connecting hole on the valve flange 41. After the annular sealing gasket 2 is installed, the metal spiral wound gasket 1 is embedded in the inner ring portion 22 and positioned using the inner ring portion 22. After the metal spiral wound gasket 1 is positioned, the connecting pipe 5 is moved closer to the power station valve 4, and the pipe flange 51 is closed towards the valve flange 41 to clamp the metal spiral wound gasket 1 and the inner ring portion 22. After the pipe flange 51 contacts the metal spiral wound gasket 1 and the inner ring portion 22, the valve flange 41 is connected to the pipe flange 41 using bolt and nut assemblies. The flange 51 is tightened to clamp the two sealing connection half-rings 3 together on the outer ring 21. The outer ring 21 is circumferentially fixed and the two sealing connection half-rings 3 are locked and fixed by the bolt and nut assembly. After the sealing connection half-rings 3 are installed, the clamping plate 32 is set at the preset position at the end of the sealing connection half-rings 3 and the clamping plate 32 is fixed to the sealing connection half-rings 3 by bolts. The metal spiral wound gasket 1 and the inner ring 22 are used as the main sealing structure between the power station valve 4 and the connecting pipe 5. The inner ring 22 can effectively position the metal spiral wound gasket 1 and prevent the metal spiral wound gasket 1 from directly squeezing and contacting the connecting bolt. The outer ring 21 can circumferentially reinforce and seal the contact between the power station valve 4 and the connecting pipe 5. On the one hand, it is used to clamp the outer ring 21, and on the other hand, it also enhances the sealing effect at the interface.

Claims

1. An interface sealing structure of a power station valve, the sealing structure comprising a metal-wound gasket (1) arranged between a valve flange (41) on the power station valve (4) and a pipe flange (51) on a corresponding connecting pipe (5), and clamped and fixed by the valve flange (41) and the pipe flange (51) and used for sealing the interface between the power station valve (4) and the connecting pipe (5); the sealing structure further comprising an annular sealing gasket (2) and two sealing connection half-rings (3), the annular sealing gasket (2) comprising an outer ring portion (21) and an inner ring portion (22), the outer ring portion (21) coaxially sleeving the outer portion of the inner ring portion (22), and the outer ring wall of the inner ring portion (22) and the center of the inner ring wall of the outer ring portion (21) being integrally formed, the inner ring portion (22) being arranged between the valve flange (41) and the pipe flange (51), and sleeving the metal-wound gasket (1), the inner ring portion (22) being clamped and fixed by the valve flange (41) and the pipe flange (51), the outer ring portion (21) sleeving the outer circular surface of the valve flange (41) and the pipe flange (51), and the two sealing connection half-rings (3) being clamped on the outer ring wall of the outer ring portion (21) and detachably connected by a bolt and nut assembly. characterized in that One end of the outer ring portion (21) extends to the outer end surface of the valve flange (41) and is arranged in a coplanar manner with the outer end surface of the valve flange (41), and the other end of the outer ring portion (21) extends to the outer end surface of the pipe flange (51) and is arranged in a coplanar manner with the outer end surface of the pipe flange (51).

2. An interface seal for a power plant valve according to claim 1, wherein: The end portion of the inner ring portion (22) is circumferentially equidistantly processed with a plurality of through holes (221), and each through hole (221) is coaxially arranged corresponding to a connecting bolt between the valve flange (41) and the pipe flange (51).

3. An interface seal for a power plant valve according to claim 2, wherein: The end surfaces of the two ends of the inner ring portion (22) are respectively processed with N sealing ring grooves (222), N being a positive integer, and the N sealing ring grooves (222) are all located between the through holes (221) and the inner ring wall of the inner ring portion (22), one sealing ring (223) is embedded in each sealing ring groove (222), and the two ends of the inner ring portion (22) are in close contact with the valve flange (41) or the pipe flange (51) through the sealing rings (223).

4. An interface seal for a power plant valve according to claim 3, wherein: The width dimension of the sealing connection half-ring (3) is the same as the width dimension of the outer ring portion (21).

5. An interface seal for a power plant valve according to claim 1 or 4, wherein: Each connecting ear plate of the two ends of the sealing connection half-ring (3) is provided with a connecting through hole extending vertically downward in the top portion, and the two sealing connection half-rings (3) are detachably connected through the cooperation of the connecting ear plates and the bolt and nut assembly.

6. An interface seal for a power plant valve according to claim 5, wherein: ​ 7. An interface seal for a power plant valve according to claim 6, wherein: Two clamping plates (32) are arranged on the end face of each sealing connecting half ring (3), and each clamping plate (32) is arranged between two connecting bolts arranged adjacently on the valve flange (41) and the pipeline flange (51). One end of each clamping plate (32) is connected to the end face of the sealing connecting half ring (3) by bolt dismounting. The other end of each clamping plate (32) extends to the outer end face of the valve flange (41) or the outer end face of the pipeline flange (51), and the inner side of the other end of each clamping plate (32) is in close contact with the outer end face of the valve flange (41) or the outer end face of the pipeline flange (51).

8. An interface seal for a power plant valve according to claim 7, wherein: A gasket (33) is arranged on the inner side of the other end of each clamping plate (32), and each clamping plate (32) is in close contact with the outer end face of the valve flange (41) or the outer end face of the pipeline flange (51) through the gasket (33).

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