Water turbine guide vane sealing assembly and water turbine

Abstract

The utility model discloses a water turbine guide vane sealing assembly and a water turbine, and relates to the technical field of water turbine sealing systems, the sealing assembly comprises a sealing strip, a pressing plate and a supporting pad; a boss is arranged on the side face of the sealing strip, and the pressing plate provides pressure for the boss to press the sealing strip. The base plate assembly comprises a base plate main body and an elastic cushion fixed on the base plate main body; the elastic cushion meets the following conditions: the elastic cushion can be deformed to be flush with the surface of the cushion plate main body in a pressed state and is kept in a convex form relative to the surface of the cushion plate main body in a natural state, the surface is the inner side surface and / or the outer side surface of the cushion plate main body, the inner side surface is the surface, in contact with the boss, on the cushion plate main body, and the outer side surface is the surface, in contact with the boss, on the cushion plate main body. The outer side face is the surface, used for making contact with a pressing plate, of the base plate body, the water turbine comprises the sealing assembly, and the sealing assembly not only has the advantage of being high in position stability of the base plate body, but also has the advantage of being easy to pull out the base plate body.

Description

Technical Field

[0001] This utility model relates to the technical field of water turbine sealing systems, and in particular to a water turbine guide vane sealing assembly and a water turbine. Background Technology

[0002] The guide vane end face sealing assembly of a hydro turbine (hydro generator) is an important component of the guide vane sealing system. It is used to seal the gap between the guide vane end and the top cover and bottom ring. The specific principle is to use a sealing strip that fits tightly between the guide vane end and the top cover / bottom ring to reduce leakage on both sides of the guide vane. Especially when the hydro turbine is completely closed or the opening is small, the quality of its sealing performance has a significant impact on the amount of water flowing through both sides of the guide vane. Therefore, the performance of the end face sealing assembly directly affects the unit's operating efficiency, operating stability, and service life.

[0003] In the prior art, an important form of the sealing assembly for the end face of a turbine guide vane is a sealing strip combined with a pressure compensation structure. This method can compensate for wear after the sealing assembly is worn, and at the same time has the ability to ensure that the sealing assembly can have sufficient sealing force for a long time. The specific implementation method is as shown in the technical solution of the applicant's earlier patent application number CN202221840531.8. In this solution, the mounting plate is a top cover or bottom ring, the metal sealing gasket is the sealing strip that contacts the end face of the guide vane, and the pressure compensation mechanism includes an elastic sealing gasket and an air source device.

[0004] In the applicant's earlier proposed technical solution, when the metal sealing gasket reaches its maximum wear and still cannot achieve sufficient sealing contact force under the action of the pressure compensation mechanism, a gasket is installed on the sealing assembly. This solution offers the advantages of conveniently restoring the performance of the sealing assembly and extending its service life. Furthermore, for situations where the sealing strip is squeezed against the guide vane end face, causing the protrusion on the sealing strip to disappear from mutual compression with the pressure plate, the gasket and protrusion are bonded together using hot melt adhesive. This effectively ensures that the gasket is stably confined between the protrusion and the pressure plate. However, before removing the gasket, a step is required to treat the hot melt adhesive to remove the connection between the gasket and the protrusion. Utility Model Content

[0005] In view of the above-mentioned operational characteristics of removing the gasket from the sealing assembly, this utility model provides a turbine guide vane sealing assembly and a turbine. This sealing assembly not only has the characteristics of strong positional stability of the gasket body, but also has the characteristics of simple operation of removing the gasket body.

[0006] To address the aforementioned problems, this utility model provides a turbine guide vane sealing assembly and a turbine that solve the problems through the following technical points: A turbine guide vane sealing assembly includes a sealing strip, a pressure plate for pressing the sealing strip, and a support pad for supporting the sealing strip; a boss is provided on the side of the sealing strip, and the pressure plate presses the sealing strip by providing pressure to the boss; it also includes a pad assembly disposed between the pressure plate and the boss.

[0007] The pad assembly includes a pad body and an elastic pad fixed to the pad body; the elastic pad satisfies the following conditions: under pressure, it can deform to be flush with the surface of the pad body, and under natural conditions, it maintains a convex shape relative to the surface of the pad body. The surface is the inner side and / or outer side of the pad body, the inner side is the surface on the pad body for contacting the boss, and the outer side is the surface on the pad body for contacting the pressure plate.

[0008] When used as a sealing assembly for the end face of a turbine guide vane, this solution can be applied as follows: The pressure plates on both sides of the sealing strip are fixed to a mounting base (top cover or bottom ring) using clamping bolts. The sealing strip and support pad are confined between the two pressure plates. The support pad is located inside the sealing strip, and under the action of the support pad, the maximum extension length of the sealing strip is limited by the support provided by the pressure plates to the boss. Depending on the opening and closing status of the turbine guide vane, the state of the turbine guide vane end face sealing assembly may be as follows: The guide vane end face is not in contact with the sealing strip, and the sealing strip is pushed to the outermost side under the action of the support pad. In this case, the pad assembly, as a support structure between the pressure plates and the boss, can be stably constrained between the pressure plates and the boss. When the guide vane is closed or opened at a small angle, it is pressed against the sealing strip. In this case, relative to the outermost state, the sealing strip is moved backward under the action of the guide vane end face. If the pad assembly cannot compensate for the increased gap between the pressure plates and the boss, the pad assembly loses the clamping effect of the pressure plates and the boss. In the second state described above, in order to maintain the positional reliability of the gasket on the sealing assembly, the applicant has previously provided a technical solution based on hot melt adhesive to fix the gasket assembly. When it is necessary to remove the gasket assembly so that the sealing strip can be further released, a hot melt process is required to remove the connection between the gasket assembly and the sealing strip, which has a certain impact on the maintenance efficiency of the sealing assembly.

[0009] Based on the above, a technical solution is provided that uses an elastic pad to maintain the position of the pad assembly between the sealing strip and the pressure plate. In this solution, when the guide vane end face does not affect the extension of the sealing strip relative to the pressure plate (the first state mentioned above), the support pad provides pressure to the inner side of the sealing strip, forcing the sealing strip to move to the position of the pressure plate support boss. At this time, depending on the magnitude of the force provided by the support pad to the sealing strip, the elastic pad on the pad assembly located between the sealing strip and the pressure plate is deformed under pressure. When the support force of the elastic pad on the sealing strip is large, the elastic pad deforms to be flush with the surface of the pad body. In this state, the boss and the pressure plate reach the minimum distance, specifically the thickness of the pad body, and the force borne by the elastic pad reaches the maximum value (the force between the sealing strip and the pressure plate is transmitted through the pad body). That is, in this solution, when the support force of the support pad on the sealing strip is large, when the inner side of the pad body is in contact with the boss and the outer side is in contact with the pressure plate, the increase in support force will not cause a further increase in the deformation of the elastic pad. For forces that may act on the gasket assembly, this design protects the elastic gasket and extends its service life. During the guide vane closing process, as the guide vane rotates, when the end face of the guide vane acts on the guide surface of the sealing strip and presses the sealing strip down, the distance between the boss and the pressure plate increases. At this time, the elastic gasket rebounds, ensuring that the gasket assembly still has the characteristic of the pressure plate and the sealing strip providing clamping force during this increased distance. Thus, when the sealing strip acts on the end face of the guide vane, the presence of the above clamping force makes the structural design of this design advantageous in maintaining the position of the gasket assembly on the sealing assembly. When the top surface of the sealing strip needs to be removed to release the sealing strip due to wear, the sealing strip is pressed down to release the gasket assembly. Since there is no adhesion or other connection between the gasket assembly, the sealing strip, and the pressure plate, the gasket assembly can be efficiently removed, which is beneficial for further improving the maintenance efficiency and convenience of the sealing assembly.

[0010] As those skilled in the art, when the elastic pad deforms under pressure to be flush with the surface of the pad body, the force between the boss and the pressure plate is transmitted through the pad body. This state is used to prevent the elastic pad from undergoing permanent deformation under excessive thrust of the support pad on the sealing strip. The above-mentioned shape of maintaining a protrusion relative to the surface of the pad body in the natural state means that the elastic pad has the ability to protrude relative to the pad body, so that the elastic pad can maintain the clamping force of the pressure plate and the boss on the pad assembly through elastic rebound.

[0011] As a further technical solution for the aforementioned turbine guide vane sealing assembly:

[0012] The pad body is provided with a groove, and the elastic pad is installed in the groove. When the elastic pad is deformed to be flush with the surface of the pad body, the elastic pad is completely contained in the groove.

[0013] The above provides a specific structure for a pad assembly, which involves creating a groove on the pad body and installing an elastic pad within the groove. The groove is large enough to accommodate all the elastic pads. The elastic pads can extend from the groove in their natural state and can be accommodated within the groove through elastic deformation under pressure. In specific implementations, besides using annular grooves and elastic rings as described below, grooves can also be machined on the inner and / or outer surfaces of the pad body, with elastic pads placed in each groove. When an elastic pad is placed on only one side of the pad body via a groove, during the movement of the sealing strip towards the pressure plate, one side of the pad assembly interacts with the pressure plate or boss via the pad body, while the other side interacts with the pressure plate or boss via the elastic pad. In this application, the clamping force can still be maintained by the elastic pad. However, in use, there is a possibility that the surface of the pad body may directly adhere to the boss or pressure plate during use. When it is necessary to remove the pad assembly, the adhesion can be broken by appropriately tapping the end of the pad body, or by tapping the sealing strip or pressure plate, through vibration. A better approach is to have elastic pads on both the inner and outer sides of the pad body. This effectively reduces the possibility of the pad body sticking together. As for any sticking that may occur on the elastic pads, since the elastic pads are easily torn when the pad body is pulled, it will not substantially affect the extraction efficiency of the pad assembly.

[0014] The groove is an annular groove located on the outer periphery of the pad body and extending in the circumferential direction around the pad body, and the elastic pad is an elastic ring sleeved in the annular groove.

[0015] The above provides a type of groove and a type of elastic pad. In this solution, the elastic pad can be assembled on the pad body by directly fitting the elastic ring into the annular groove. The assembly is convenient. At the same time, it can make the pad body have elastic pads at all positions in the circumferential direction and can utilize the space on the side of the pad body to accommodate the elastic pads during compression deformation.

[0016] The annular groove has a recessed central region, and the elastic ring fits into the central region.

[0017] The purpose of the above design is to constrain the position of the elastic pad on the annular groove by utilizing a central recess and the elastic ring fitting within this recessed area. This prevents the elastic pad from slipping to the end of the annular groove and being clamped outside the annular groove on the pad body, which could lead to localized permanent deformation or even damage under the significant force between the boss and the pressure plate, thus affecting the reliability of the elastic pad. Simultaneously, by using this recess to constrain the position of the elastic ring on the annular groove, it avoids the situation where, if the inner ring of the elastic ring is bonded to the annular groove, the constrained inner ring would affect the natural deformation of the elastic pad under pressure, thereby impacting the lifespan of the elastic pad.

[0018] The number of elastic pads is greater than 1, and the elastic pads are arranged at intervals along the length of the pad body.

[0019] The above scheme aims to utilize a greater number of elastic pads to stabilize the position of the sealing assembly on the pad assembly in all states.

[0020] It also includes a socket provided on the pad body, the socket having an opening located on the outer side of the pad body;

[0021] There are multiple sockets, which are spaced apart along the length of the pad body.

[0022] In the above scheme, the insertion hole serves as the operating hole for removing the pad assembly. Specifically, a pulling tool is inserted into the insertion hole at the end face of the sealing assembly, and the pulling tool provides an outward pulling force to the pad body. The number and arrangement of the insertion holes are designed to allow for the selection of appropriate insertion holes and the pulling tool to facilitate the complete removal of the pad assembly at different extraction lengths. In practical applications, both ends of the pad body have insertion holes. According to the general shape of existing sealing assemblies, in the initial state, the insertion holes at this position are covered by the pressure plate. If the pad assembly is removed from the left end of the sealing assembly, the pad body at the right end of the sealing assembly can be tapped. When the pad body moves to the left and exposes the insertion hole at the left end, the subsequent extraction operation can be completed using this insertion hole.

[0023] The pad assembly includes a left half and a right half that are independent of each other. The left half serves as a support structure between the upper sealing strip on the left side of the sealing assembly and the pressure plate, and the right half serves as a support structure between the upper sealing strip on the right side of the sealing assembly and the pressure plate.

[0024] Both the left and right halves have a pad body and an elastic pad.

[0025] This solution aims to achieve the following: This type of sealing assembly is generally installed on a mounting base between two guide vanes. The guide vanes rotate synchronously, and a single sealing assembly serves to seal the end faces of both guide vanes. Due to installation errors, the end faces of the two guide vanes may be misaligned. In this solution, for the configuration of the pad assembly, the left and right halves can be configured independently to accommodate the different guide vane end face positions and the required extension height of the sealing strip. During maintenance of the sealing assembly, either the left or right half can be removed individually. It should be noted that when the sealing strip is an integral structure, to prevent the sealing strip from warping and affecting the sealing performance, the sealing strip should preferably use a flexible polymer structure with wear resistance and sufficient strength. This allows for compensation for warping through different deformations at the left and right ends, ensuring a good sealing effect. When the sealing strip is a metal structure, it is advisable to configure the sealing strip as including independent left and right halves, that is, the sealing strips at different ends of the sealing assembly are supported by different pad assemblies.

[0026] It also includes a side gasket, which is a flexible gasket fixed to the side of the sealing strip. The side gasket is located above the boss and is used to fill the gap between the sealing strip and the pressure plate.

[0027] This solution aims to: fill the gap with the side pad to prevent mud and sand from entering the gap, which could cause the effective thrust of the support pad on the sealing strip to be uncontrollable, or the sealing strip to be unable to effectively retract under the push of the guide vane end face, resulting in damage to the front end of the sealing strip.

[0028] The pad body is a metal sheet, and the elastic pad is a silicone rubber pad.

[0029] In this design, the metal sheet pad body can effectively maintain its shape stability, and the silicone rubber dot elastic pad can maintain good elasticity for a long time under long-term pressure.

[0030] This solution also relates to a water turbine, including a mounting base for a top cover or a bottom ring, and a guide vane end face sealing assembly mounted on the mounting base. The guide vane end face sealing assembly is a sealing assembly as described in any of the above embodiments, wherein the pressure plate is connected to the mounting base by connecting bolts, and both sides of the sealing strip have pressure plates, and the support pad is located in the gap between the two pressure plates and is located inside the sealing strip.

[0031] The above-mentioned water turbine includes the sealing assembly, which is a specific application scheme of the sealing assembly.

[0032] This utility model has the following beneficial effects:

[0033] This solution provides a technical approach for maintaining the position of the gasket assembly between the sealing strip and the pressure plate based on an elastic gasket. It features the characteristics of protecting the elastic gasket and extending its service life; it is advantageous for maintaining the position of the gasket assembly on the sealing assembly; and it is beneficial for further improving the maintenance efficiency and convenience of the sealing assembly. Attached Figure Description

[0034] Figure 1 This is a structural schematic diagram of a specific application embodiment of the turbine guide vane sealing assembly described in this solution;

[0035] Figure 2 This is a top view of the pad body described in this solution;

[0036] Figure 3 This is a top view of the pad assembly described in this solution;

[0037] Figure 4 for Figure 1 A magnified view of the area indicated by label 3 in the attached figure.

[0038] The reference numerals in the attached drawings are as follows: 1. Sealing strip, 2. Pressure plate, 3. Gasket assembly, 31. Gasket body, 32. Insertion hole, 33. Groove, 34. Elastic pad, 4. Support pad, 5. Plug, 6. Tightening bolt, 7. Side gasket, 8. Mounting base. Detailed Implementation

[0039] The present invention will be further described in detail below with reference to the embodiments, but the present invention is not limited to the following embodiments:

[0040] Example 1:

[0041] like Figures 1 to 4 As shown, a turbine guide vane sealing assembly includes a sealing strip 1, a pressure plate 2 for pressing the sealing strip 1, and a support pad 4 for providing support for the sealing strip 1; a boss is provided on the side of the sealing strip 1, and the pressure plate 2 presses the sealing strip 1 by providing pressure to the boss; it also includes a pad assembly 3 disposed between the pressure plate 2 and the boss.

[0042] The pad assembly 3 includes a pad body and an elastic pad 34 fixed on the pad body; the elastic pad 34 satisfies the following conditions: under pressure, it can deform to be flush with the surface of the pad body, and under natural conditions, it maintains a convex shape relative to the surface of the pad body. The surface is the inner side and / or outer side of the pad body. The inner side is the surface on the pad body that is in contact with the boss, and the outer side is the surface on the pad body that is in contact with the pressure plate 2.

[0043] When this solution is used as a sealing assembly for the end of a turbine guide vane, it can be specifically applied as follows: the pressure plates 2 on both sides of the sealing strip 1 are fixed to the mounting base 8, which is the top cover or bottom ring, by clamping bolts 6. Similar to the previous design, the plugs 5 are used to protect the clamping bolts 6. The sealing strip 1 and the support pad 4 are restricted between the two pressure plates 2. The support pad 4 is located inside the sealing strip 1. Under the action of the support pad 4, the maximum extension length of the sealing strip 1 is limited by the support provided by the pressure plates 2 to the boss. Depending on the opening and closing status of the turbine guide vanes, the state of the turbine guide vane end face sealing assembly may be as follows: The guide vane end face is not in contact with the sealing strip 1, and the sealing strip 1 is pushed to the outermost side under the action of the support pad 4. In this case, the pad assembly 3, as a support structure between the pressure plate 2 and the boss, can be stably constrained between the pressure plate 2 and the boss. When the guide vane is closed or opened at a small angle, it is pressed against the sealing strip 1. In this case, relative to the outermost state mentioned above, the sealing strip 1 is moved backward under the action of the guide vane end face. If the pad assembly cannot compensate for the increased gap between the pressure plate and the boss, the pad assembly 3 loses the clamping of the pressure plate 2 and the boss. In the second state mentioned above, to maintain the positional reliability of the pad on the sealing assembly, the applicant previously provided a technical solution based on hot melt adhesive to fix the pad assembly 3. When it is necessary to remove the pad assembly 3 to allow the sealing strip 1 to be further released, a hot melt process is required to remove the connection between the pad assembly 3 and the sealing strip 1, which has a certain impact on the maintenance efficiency of the sealing assembly.

[0044] Based on the above, a technical solution is provided that uses an elastic pad 34 to maintain the position of the pad assembly 3 between the sealing strip 1 and the pressure plate 2. In this solution, when the guide vane end face does not affect the extension of the sealing strip 1 relative to the pressure plate 2 (the first state mentioned above), the support pad 4 provides pressure to the inner side of the sealing strip 1, forcing the sealing strip 1 to move to the position of the support boss of the pressure plate 2. At this time, according to the magnitude of the force provided by the support pad 4 to the sealing strip 1, the elastic pad 34 on the pad assembly 3 located between the sealing strip 1 and the pressure plate 2 is deformed by pressure. When the elastic pad 34 When the supporting force on the sealing strip 1 is relatively large, the elastic pad 34 deforms to be flush with the surface of the pad body. In this state, the distance between the boss and the pressure plate 2 reaches its minimum, specifically the thickness of the pad body 31. The force borne by the elastic pad 34 reaches its maximum (the force between the sealing strip 1 and the pressure plate 2 is transmitted through the pad body 31). That is, in this scheme, when the supporting force of the support pad 4 on the sealing strip 1 is large, when the inner side of the pad body 31 is in contact with the boss and the outer side is in contact with the pressure plate 2, the increase in supporting force will not cause the elastic pad 34 to deform. With the further increase in quantity, for the larger force that may act on the pad assembly 3, this solution has the characteristics of protecting the elastic pad 34 and extending the service life of the elastic pad 34; during the closing process of the guide vane, as the guide vane rotates, when the end face of the guide vane acts on the guide surface of the side of the sealing strip 1 and causes the sealing strip 1 to be pressed down, the distance between the boss and the pressure plate 2 increases. At this time, the elastic pad 34 rebounds, so that the pad assembly 3 still has the characteristics of the pressure plate 2 and the sealing strip 1 being able to provide clamping force for the pad assembly 3 during the process of this distance increase. Thus, when the sealing strip 1 acts on the end face of the guide vane, due to the above clamping force, the structural design of this solution is beneficial to maintaining the position of the pad assembly 3 on the sealing assembly; when the top surface of the sealing strip 1 needs to be removed to release the sealing strip 1 due to wear, the sealing strip 1 is pressed down to release the pad assembly 3. Since the pad assembly 3 is not adhered to the sealing strip 1 and has no other connection relationship, the pad assembly 3 can be extracted efficiently, which is beneficial to further improving the maintenance efficiency and convenience of the sealing assembly.

[0045] As those skilled in the art, when the elastic pad 34 is deformed under pressure to be flush with the surface of the pad body, the force between the boss and the pressure plate 2 is transmitted through the pad body 31. This state is used to prevent the elastic pad 34 from undergoing permanent deformation under excessive thrust of the support pad 4 on the sealing strip 1. The above-mentioned shape of maintaining a protrusion relative to the surface of the pad body in the natural state means that the elastic pad 34 has the ability to protrude relative to the pad body 31, so that the elastic pad 34 can maintain the clamping force of the pressure plate 2 and the boss on the pad assembly 3 through elastic rebound.

[0046] Example 2:

[0047] This embodiment is a further refinement of embodiment 1:

[0048] The pad body 31 is provided with a groove 33, and the elastic pad 34 is installed in the groove 33. When the elastic pad 34 is deformed to be flush with the surface of the pad body, the elastic pad 34 is completely contained in the groove 33.

[0049] The above provides a specific structure of the pad assembly 3, which is that a groove is provided on the pad body 31 and the elastic pad 34 is installed in the groove. The size of the groove is sufficient to accommodate all the elastic pads 34. The elastic pads 34 can extend out of the groove in the natural state and can be accommodated in the groove 33 through elastic deformation in the compressed state. In specific implementation, in addition to the annular groove and elastic ring method provided below, grooves 33 can also be machined on the inner and / or outer surfaces of the pad body 31, and elastic pads 34 can be provided in each groove 33. When the elastic pad 34 is provided on only one side of the pad body 31 through the groove 33, during the process of the sealing strip 1 moving towards the inside of the pressure plate 2, one side of the pad assembly 3 interacts with the pressure plate 2 or the boss through the pad body 31, and the other side interacts with the pressure plate 2 or the boss through the elastic pad 34. Under this application, the clamping force can still be maintained by the elastic pad 34. However, when this solution is used, there is a possibility that the surface of the pad body 31 may directly stick to the boss or the pressure plate 2 during use. When it is necessary to remove the pad assembly 3, the sticking can be broken by appropriately tapping the end of the pad body 31, or by tapping the sealing strip 1 or the pressure plate 2 through vibration. A preferred approach is to have elastic pads 34 on both the inner and outer sides of the pad body 31. This approach can effectively reduce the possibility of adhesion of the pad body 31. As for adhesion that may occur on the elastic pads 34, since the elastic pads 34 are easily torn when the pad body 31 is pulled, it will not substantially affect the extraction efficiency of the pad assembly 3.

[0050] Example 3:

[0051] This embodiment is a further refinement of embodiment 2:

[0052] The groove 33 is an annular groove provided on the outer periphery of the pad body 31 and extending in the circumferential direction around the pad body 31, and the elastic pad 34 is an elastic ring sleeved in the annular groove.

[0053] The above provides a form of groove 33 and a form of elastic pad 34. In this solution, the elastic pad 34 can be assembled on the pad body 31 by directly fitting the elastic ring into the annular groove. The assembly is convenient. At the same time, it can make the pad body 31 have elastic pads 34 at all positions in the circumference and can use the space on the side of the pad body 31 to accommodate the elastic pads 34 during compression deformation.

[0054] Example 4:

[0055] This embodiment is a further refinement of embodiment 3:

[0056] The annular groove has a recessed central region, and the elastic ring fits into the central region.

[0057] The purpose of the above design is to constrain the position of the elastic pad 34 on the annular groove by using a central recess and the elastic ring fitting within this recessed area. This prevents the elastic pad 34 from slipping to the end of the annular groove and being clamped outside the annular groove on the pad body 31, which could lead to localized permanent deformation or even damage under the greater force between the boss and the pressure plate 2, thus affecting the reliability of the elastic pad 34. Simultaneously, by using this recess to constrain the position of the elastic ring on the annular groove, it avoids the situation where, if the inner ring of the elastic ring is bonded to the annular groove, the inner ring of the elastic ring is constrained, affecting the natural deformation of the elastic pad 34 under pressure, thus impacting its lifespan.

[0058] Example 5:

[0059] This embodiment is a further refinement of embodiment 1:

[0060] The number of elastic pads 34 is greater than 1, and the elastic pads 34 are arranged at intervals along the length of the pad body 31.

[0061] The above scheme aims to utilize a greater number of elastic pads 34 to stabilize the position of the sealing assembly on the pad assembly 3 in all states.

[0062] Example 6:

[0063] This embodiment is a further refinement of embodiment 1:

[0064] It also includes a socket 32 ​​provided on the pad body 31, the socket 32 ​​having an opening located on the outer side of the pad body 31;

[0065] There are multiple sockets 32, which are arranged at intervals along the length of the pad body 31.

[0066] In the above scheme, the insertion hole 32 serves as the operating hole for removing the pad assembly 3. Specifically, at the end face of the sealing assembly, a turning tool is inserted into the insertion hole 32, and the turning tool provides an outward pulling force to the pad body 31. The number and arrangement of the insertion holes 32 are designed to allow for the selection of appropriate insertion holes 32 to cooperate with the turning tool at different extraction lengths of the pad assembly 3, so as to facilitate the complete extraction of the pad assembly 3. In specific applications, both ends of the pad body 31 have insertion holes 32. According to the general shape of existing sealing assemblies, in the initial state, the insertion holes 32 at this position are covered by the pressure plate 2. If the pad assembly 3 is extracted from the left end of the sealing assembly, the pad body 31 at the right end of the sealing assembly can be tapped. When the pad body 31 moves to the left and exposes the insertion hole 32 at the left end, the subsequent extraction operation can be completed using the insertion hole 32.

[0067] Example 7:

[0068] This embodiment is a further refinement of embodiment 1:

[0069] The pad assembly 3 includes a left half and a right half that are independent of each other. The left half serves as a support structure between the upper sealing strip 1 on the left side of the sealing assembly and the pressure plate 2, and the right half serves as a support structure between the upper sealing strip 1 on the right side of the sealing assembly and the pressure plate 2.

[0070] Both the left and right halves have a pad body 31 and an elastic pad 34.

[0071] This solution aims to achieve the following: This type of sealing assembly is generally installed on the mounting base 8 between two guide vanes. The guide vanes have the characteristics of synchronous rotation, and a single sealing assembly serves the sealing of the end faces of both guide vanes. Due to installation errors, the end faces of the two guide vanes may be misaligned. In this solution, for the configuration of the pad assembly 3, the left and right halves can be configured independently to adapt to the different guide vane end face positions and the required extension height of the sealing strip 1. When maintaining the sealing assembly, the left or right half can be removed individually. It should be noted that when the sealing strip 1 is an integral structure, to avoid the sealing strip 1 warping and affecting the sealing performance, the sealing strip 1 should preferably use a flexible polymer structure with wear resistance and sufficient strength to compensate for warping through different deformations at the left and right ends, ensuring the sealing effect. When the sealing strip 1 is a metal structure, it is advisable to configure the sealing strip 1 as including independent left and right halves, that is, the sealing strip 1 at different ends of the sealing assembly is supported by different pad assemblies 3.

[0072] Example 8:

[0073] This embodiment is a further refinement of embodiment 1:

[0074] It also includes a side gasket 7, which is a flexible gasket fixed to the side of the sealing strip 1. The side gasket 7 is located above the boss and is used to fill the gap between the sealing strip 1 and the pressure plate 2.

[0075] This solution aims to: fill the gap by the side pad, and prevent mud and sand from entering the gap, which would cause the effective thrust of the support pad 4 on the sealing strip 1 to be uncontrollable, or the sealing strip 1 to be unable to retract effectively under the push of the guide vane end face, resulting in damage to the front end of the sealing strip 1, etc.

[0076] Example 9:

[0077] This embodiment is a further refinement of embodiment 1:

[0078] The pad body 31 is a metal sheet, and the elastic pad 34 is a silicone rubber pad.

[0079] In this design, the metal sheet pad body 31 can effectively maintain its shape stability, and the silicone rubber dot elastic pad 34 can maintain good elasticity for a long time under long-term pressure.

[0080] Example 10:

[0081] This embodiment provides a water turbine based on any of the above embodiments, including a mounting base 8 which is a top cover or a bottom ring, and a guide vane end face sealing assembly mounted on the mounting base 8. The guide vane end face sealing assembly is the sealing assembly described in any of the above embodiments. The pressure plate 2 is connected to the mounting base 8 by connecting bolts. Both sides of the sealing strip 1 have pressure plates 2, and the support pad 4 is located in the gap between the two pressure plates 2 and is located inside the sealing strip 1.

[0082] The above-mentioned water turbine includes the sealing assembly, which is a specific application scheme of the sealing assembly.

[0083] The above description, in conjunction with specific preferred embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, other embodiments derived without departing from the technical solution of the present invention should be included within the protection scope of the present invention.

Claims

1. A turbine guide vane sealing assembly, comprising a sealing strip (1), a pressure plate (2) for pressing the sealing strip (1), and a support pad (4) for providing support for the sealing strip (1); a boss is provided on the side of the sealing strip (1), and the pressure plate (2) presses the sealing strip (1) by providing pressure to the boss; further comprising a pad assembly (3) disposed between the pressure plate (2) and the boss. Its features are, The pad assembly (3) includes a pad body (31) and an elastic pad (34) fixed on the pad body (31); the elastic pad (34) satisfies the following: under pressure, it can be deformed to be flush with the surface of the pad body (31), and under natural state, it maintains a convex shape relative to the surface of the pad body (31). The surface is the inner side and / or outer side of the pad body (31). The inner side is the surface on the pad body (31) for contacting the boss, and the outer side is the surface on the pad body (31) for contacting the pressure plate (2).

2. The turbine guide vane sealing assembly according to claim 1, characterized in that, The pad body (31) is provided with a groove (33), and the elastic pad (34) is installed in the groove (33). When the elastic pad (34) is deformed to be flush with the surface of the pad body (31), the elastic pad (34) is completely contained in the groove (33).

3. The turbine guide vane sealing assembly according to claim 2, characterized in that, The groove (33) is an annular groove provided on the outer periphery of the pad body (31) and extending in the circumferential direction around the pad body (31), and the elastic pad (34) is an elastic ring sleeved in the annular groove.

4. A turbine guide vane sealing assembly according to claim 3, characterized in that, The annular groove has a recessed central region, and the elastic ring fits into the central region.

5. A turbine guide vane sealing assembly according to any one of claims 1 to 4, characterized in that, The number of elastic pads (34) is greater than 1, and the elastic pads (34) are arranged at intervals along the length of the pad body (31).

6. A turbine guide vane sealing assembly according to any one of claims 1 to 4, characterized in that, It also includes a socket (32) provided on the pad body (31), the socket having an opening located on the outer side of the pad body (31); There are multiple sockets (32), which are arranged at intervals along the length of the pad body (31).

7. A turbine guide vane sealing assembly according to any one of claims 1 to 4, characterized in that, The pad assembly (3) includes a left half and a right half that are independent of each other. The left half serves as a support structure between the upper sealing strip (1) on the left side of the sealing assembly and the pressure plate (2), and the right half serves as a support structure between the upper sealing strip (1) on the right side of the sealing assembly and the pressure plate (2). Both the left and right halves have a pad body (31) and an elastic pad (34).

8. A turbine guide vane sealing assembly according to any one of claims 1 to 4, characterized in that, It also includes a side gasket (7) that is fixed to the side of the sealing strip (1) and is a flexible gasket. The side gasket (7) is located above the boss and is used to fill the gap between the sealing strip (1) and the pressure plate (2).

9. A turbine guide vane sealing assembly according to any one of claims 1 to 4, characterized in that, The pad body (31) is a metal sheet, and the elastic pad (34) is a silicone rubber pad.

10. A water turbine, comprising a mounting base (8) as a top cover or bottom ring, and a guide vane end face sealing assembly mounted on the mounting base (8), characterized in that, The guide vane end face sealing assembly is the sealing assembly according to any one of claims 1 to 9, wherein the pressure plate (2) is connected to the mounting base (8) by connecting bolts (6), both sides of the sealing strip (1) have pressure plates (2), and the support pad (4) is located in the gap between the two pressure plates (2) and is located inside the sealing strip (1).

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