Water turbine paddle sealing assembly and water turbine

Abstract

The utility model discloses a water turbine paddle sealing assembly and a water turbine, and relates to the technical field of water turbine sealing, the water turbine paddle sealing assembly comprises a sealing ring lamination layer and a second supporting ring arranged at the outer end of the sealing ring lamination layer, the second supporting ring is provided with a sediment leading-out hole, and the water turbine paddle sealing assembly further comprises an inner ring and an outer ring which are both flexible rings, an inner side flange is arranged on the inner side of the second supporting ring, an outer side flange is arranged on the outer side of the second supporting ring, the inner ring is arranged on the inner side of the second supporting ring and clamped between the outer end of the sealing ring lamination layer and the inner side flange, and the outer ring is arranged on the outer side of the second supporting ring and clamped between the outer end of the sealing ring lamination layer and the outer side flange; the inner ring protrudes relative to the inner side flange, the sediment guide-out hole is located in the outer side of the inner ring, and the water turbine comprises the water turbine paddle sealing assembly. According to the technical scheme, damage to the paddle shaft caused by silt in water and damage to a sealing structure on the sealing assembly can be effectively reduced.

Description

Technical Field

[0001] This utility model relates to the field of water turbine sealing technology, and in particular to a water turbine blade sealing assembly and a water turbine. Background Technology

[0002] The turbine blade sealing assembly, as a two-way sealing structure (used to prevent oil leakage from inside the runner body into the flow channel, and at the same time to prevent water and impurities in the flow channel from seeping into the runner body), is specifically used between the runner body and the blade shaft of the turbine. Through its axial sealing function, it achieves the sealing and isolation of oil inside the runner body and water outside the runner body.

[0003] High-performance turbine blade sealing assemblies are considered to need to maintain stable and reliable performance during a major turbine overhaul. In the prior art, the widely used sealing assemblies typically employ a combination of X-type and V-type sealing rings, forming a layered composite sealing structure. This structure utilizes multiple lips and the radial compensation capability of each lip under elastic compression to achieve reliable sealing. A specific technical solution is provided in patent application number CN201220237280.4.

[0004] Meanwhile, the design of turbine blade sealing components should also consider the performance indicators of sealing materials. For example, the sealing rings used mainly include PU (polyurethane) sealing rings and NBR (nitrile rubber) sealing rings. In existing composite sealing structures, there is a technical solution that uses PU sealing rings and NBR sealing rings in a layered combination to achieve, for example, the characteristic of NBR sealing rings that are not easy to loosen or age under long-term prestress, thus ensuring the contact quality between the sealing component and the blade shaft; and the characteristic of PU sealing rings that have a fast elastic recovery speed, thus ensuring the dynamic sealing effect under blade angle adjustment.

[0005] Depending on the location of the turbine, the operating environment of the blade sealing assembly also includes water quality and flow velocity conditions. Further optimizing the structural design of the turbine blade sealing assembly to enable it to adapt well to various operating environment conditions is an important measure to ensure the working efficiency of the turbine. Utility Model Content

[0006] To address the aforementioned issue of optimizing the structural design of turbine blade sealing components, this utility model provides a turbine blade sealing component and a turbine. This technical solution can effectively reduce the damage caused by silt in the water to the blade shaft and the sealing structure on the sealing component.

[0007] To address the aforementioned problems, the turbine blade sealing assembly and turbine provided by this utility model solve the problems through the following technical points: The turbine blade sealing assembly includes a sealing ring stack and a second support ring disposed at the outer end of the sealing ring stack. The second support ring is provided with a mud and sand discharge hole connecting its inner and outer sides. It also includes an inner ring and an outer ring, both of which are flexible rings. The inner side of the second support ring is provided with an inner flange coaxial with it, and the outer side of the second support ring is provided with an outer flange coaxial with it. The inner ring is disposed inside the second support ring and sandwiched between the outer end of the sealing ring stack and the inner flange. The outer ring is disposed outside the second support ring and sandwiched between the outer end of the sealing ring stack and the outer flange.

[0008] The inner ring protrudes relative to the inner flange, and the mud and sand outlet is located on the outer side of the inner ring.

[0009] In the prior art, the sealing ring stack used for turbine blade seals is a stacked structure formed by overlapping multiple sealing rings. In turbine blade seals, X-type sealing rings and V-type sealing rings are usually stacked, and support rings are usually also used at both ends of the sealing ring stack. The support rings are used to transmit compressive force to the sealing ring stack to constrain the sealing ring stack so that the inner side is sealed with the blade shaft and the outer side is sealed with the channel on the runner.

[0010] The above structural forms are common implementations of turbine blade sealing assemblies. This solution addresses the issue that turbine blade sealing assemblies may be used in water bodies containing a large amount of silt. During long-term operation, this silt may enter between the sealing ring stack and the blade shaft. For turbines with adjustable blades (such as axial-flow propeller turbines), when the blade angle is adjusted, this silt will become abrasive particles located between the blade shaft and the sealing ring stack during blade rotation, accelerating damage to the blade shaft surface and the inner side of the sealing ring stack. To address this problem, a technical solution is proposed that a silt outlet hole is set on the second support ring, and an inner ring and an outer ring are set between the silt outlet hole and the sealing ring stack.

[0011] Specifically, the second support ring acts on the outer end of the sealing ring stack. In practical application, the outer end of the second support ring interacts with the pressure plate mounted on the impeller body. When sediment in the water enters the gap between the first support ring and the impeller shaft through the gap between the pressure plate and the impeller shaft, the inner ring protruding relative to the inner flange acts as a stop ring to prevent the sediment from further moving into the sealing ring stack. Under the centrifugal force generated by the rotation of the impeller body, this sediment is discharged through the sediment discharge hole located on the inner side of the second support ring, and through the sediment discharge hole located on the outer side of the second support ring. Therefore, this solution uses the inner ring to act as a barrier to prevent sediment from further penetrating into the sealing ring stack. If it cannot completely prevent sediment from penetrating, the sediment discharge hole reduces the concentration of sediment particles at the sealing component location, thereby reducing the damage caused by sediment in the water to the impeller shaft and the sealing ring stack on the sealing component when the impeller rotates.

[0012] The inner and outer flanges can be annular structures integrally formed with the second support ring and located on the inner and outer sides of the second support ring, respectively. Alternatively, they can be annular structures welded or snapped onto the inner and outer sides of the second support ring. Their function is to allow the second support ring to provide pressure towards the inner end of the sealing ring stack for the inner and outer rings, respectively. This pressure forces the inner and outer rings to deform and constrains their axial position on the second support ring, ensuring that the inner and outer rings effectively prevent sediment from moving further towards the sealing ring stack. Since the second support ring is typically configured with an inner diameter larger than the outer diameter of the impeller shaft and an outer diameter smaller than the diameter of the hole (shaft hole) on the runner body, the outer ring, in conjunction with the inner ring, is used to balance the pressure exerted by the inner and outer sides of the second support ring on the sealing ring stack.

[0013] As a further technical solution for the aforementioned turbine blade sealing assembly:

[0014] The dimensions of the inner ring are such that, under the compression of the inner flange and the sealing ring stack, it can fit with the turbine blade shaft to form an annular contact line or contact surface.

[0015] The outer ring is sized such that it can fit against the turbine runner to form an annular contact line or contact surface under the compression of the outer flange and the sealing ring stack.

[0016] The inner ring and the outer ring are located at the same axial position as the second support ring;

[0017] In its natural state, the inner and outer rings have the same thickness.

[0018] The above scheme is as follows: the inner ring's dimensions ensure that its inner side fits well with the blade shaft side under corresponding compression, and the outer ring's dimensions ensure that its outer side fits well with the channel surface on the runner body under corresponding compression. This effectively prevents mud and sand from entering between the sealing ring stack and the blade shaft, causing abrasive wear, and from accumulating in the cavities of the sealing ring stack, thus affecting the deformation of the sealing ring stack under pressure adaptation. The same axial position and equal thickness design aim to provide balanced support for the sealing ring stack from both the inner and outer sides of the second support ring.

[0019] The number of sediment discharge holes is multiple, and the sediment discharge holes are evenly arranged in the circumferential direction of the second support ring.

[0020] The above scheme can effectively ensure the discharge of mud and sand at various locations inside the second support ring.

[0021] The sealing ring stack includes a first stack, an X-shaped sealing ring, and a second stack, which are stacked sequentially from the inner end to the outer end. Both the first stack and the second stack are stacked structures formed by stacking two or more V-shaped sealing rings.

[0022] The recessed side of the first stack faces the inner end of the turbine blade sealing assembly, and the recessed side of the second stack faces the outer end of the turbine blade sealing assembly.

[0023] It also includes a first support ring that mates with the inner end of the first stack, the outer end of the first support ring being embedded in a groove at the end of the first stack;

[0024] The inner end of the second support ring is embedded in the groove at the end of the second stack.

[0025] The above provides a specific implementation of a sealing ring stack, which uses X-type and V-type sealing rings to form the sealing ring stack, creating multiple sealing lips. Each sealing lip can adapt to the contact pressure of the sealing surface through deformation under the pressure difference on both sides, providing a reliable seal and minimizing resistance to the rotation of the blade shaft. The first support ring is the inner support ring of the sealing ring stack, working in conjunction with the second support ring to transmit the compressive force on the sealing ring stack and stabilize its position in the radial direction of the blade shaft.

[0026] The V-shaped sealing ring on the first layer is a nitrile rubber ring, and the V-shaped sealing ring and X-shaped sealing ring on the second layer are both polyurethane rings.

[0027] In the above scheme, the first layer is the sealing ring structure near the oil side during use, and the second layer is the sealing ring structure near the water side during use. The X-shaped sealing ring is the sealing ring structure in the middle position. Using this scheme, the first layer is more likely to come into contact with oil, and using a nitrile rubber ring as the V-shaped sealing ring at this position can effectively prevent oil from affecting the long-term reliability of the first layer. The second layer is more likely to come into contact with water, and using a polyurethane ring as the V-shaped sealing ring at this position can effectively prevent water from affecting the long-term reliability of the second layer (nitrile rubber has excellent oil resistance, but it is prone to expansion and aging with long-term contact with water; polyurethane is susceptible to long-term contact with mineral oil). It is prone to swelling and softening, losing structural stability and elasticity, while exhibiting excellent hydrolysis resistance. Meanwhile, the V-type sealing ring on the second layer at the outer end of the sealing ring stack, made of polyurethane, ensures its service life when in contact with mud and sand through wear resistance far superior to that of nitrile rubber rings. It also has strong resistance to possible cavitation erosion and ideal surface stability. At the same time, the X-type sealing ring is made of polyurethane to utilize the better structural stability of the X-type sealing ring compared to the V-type sealing ring, and to utilize the strong dynamic sealing capability of the polyurethane ring to ensure the sealing reliability of the turbine blade sealing assembly under blade angle adjustment conditions.

[0028] The overlapping V-shaped sealing rings satisfy the following condition: the outer convex side of one V-shaped sealing ring is consistent with the outer concave side of the other V-shaped sealing ring, and a mutually overlapping fit is formed through the outer convex side and the concave side.

[0029] The outer end of the first support ring and the inner end of the second support ring are both embedded in the corresponding recesses of the V-shaped sealing ring. The outer end of the first support ring and the inner end of the second support ring both satisfy the following condition: during the process of embedding into the recess, the compression of the V-shaped sealing ring first occurs at the inner and outer positions of the recess.

[0030] In the above scheme, the V-shaped sealing rings are seamlessly fitted together, thus providing a sealing ring stack with a stable stacking relationship. The relationship between the outer end of the first support ring and the inner end of the second support ring and the corresponding V-shaped sealing ring is as follows: when the first support ring and the second support ring compress the corresponding V-shaped sealing ring, the compression position first occurs on the inner and outer sides of the depression. As the V-shaped sealing ring deforms, the compression position gradually moves towards the center of the depression. This provides a technical solution in which, under a small pre-tightening force, the first and second support rings at both ends can effectively increase the radial deformation of the sealing ring stack when pre-tightening the turbine blade sealing assembly.

[0031] Both the inner and outer rings are polyurethane rings.

[0032] Similarly, setting the inner and outer rings as polyurethane rings aims to utilize the hydrolysis resistance, abrasion resistance, and cavitation resistance of polyurethane rings.

[0033] Multiple sealing lips are provided on both the inner and outer sides of the sealing ring stack, arranged at intervals along the axis of the sealing ring stack, and the surface of each sealing lip is a smooth arc surface.

[0034] In the above scheme, the surface shape of the arc-shaped sealing lip is used to avoid stress concentration on the sealing lip, which would affect the long-term performance stability of the sealing lip.

[0035] This solution also relates to a water turbine, including a runner body and a blade shaft that cooperates with the runner body, and a sealing assembly disposed between the runner body and the blade shaft by a pressure plate, wherein the sealing assembly is a water turbine blade sealing assembly as described in any of the above claims.

[0036] A mud and sand discharge cavity is formed between the pressure plate and the wheel body. The mud and sand discharge cavity is connected to the opening on the outside of the second support ring. The mud and sand discharge cavity extends to the outer surface of the wheel body.

[0037] This turbine is a turbine including the aforementioned turbine blade sealing assembly, and represents a specific application of the aforementioned turbine blade sealing assembly. In this design, the sediment discharge chamber serves as a channel for sediment to pass through the sediment discharge hole and move from the inner side of the second support ring to the outside of the runner body.

[0038] As a further technical solution for the aforementioned water turbine:

[0039] The hole on the rotor body for installing the sealing component is a stepped hole with an outer diameter larger than the inner diameter. The inner end face of the sealing component is supported on the stepped surface at the end of the stepped hole. The mud and sand discharge hole is located on the outside of the second support ring and is located in the area enclosed by the outer section of the stepped hole.

[0040] The above solution provides a specific form of setting a turbine blade sealing assembly on the runner body. Specifically, a cavity surrounding the second support ring is formed by the outer section of the stepped hole to increase the width of the outer cavity of the second support ring, so that mud and sand can be discharged from the mud and sand outlet hole, then through the mud and sand outlet cavity, and finally discharged from the outer surface of the runner body.

[0041] This utility model has the following beneficial effects:

[0042] This solution utilizes the inner ring to act as a barrier, preventing further infiltration of sediment into the sealing ring stack. If this cannot be completely prevented, the sediment discharge hole reduces the concentration of sediment particles at the sealing component location. This reduces the damage caused by sediment in the water to the blade shaft and the sealing ring stack on the sealing component during blade rotation. Attached Figure Description

[0043] Figure 1 This is a cross-sectional view of a specific embodiment of the turbine blade sealing assembly described in this solution;

[0044] Figure 2 This is a partial cross-sectional view of a specific embodiment of a water turbine.

[0045] The reference numerals in the attached figures are as follows: 1. First support ring; 2. First stack; 3. X-shaped sealing ring; 4. Second stack; 5. Inner ring; 6. Second support ring; 7. Outer ring; 8. Seal outlet hole; 9. Sealing assembly; 10. Blade shaft; 11. Seal outlet cavity; 12. Pressure plate; 13. Rotor body; 14. Inner flange; 15. Outer flange. Detailed Implementation

[0046] 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:

[0047] Example 1:

[0048] like Figure 1 and Figure 2 As shown, the turbine blade sealing assembly includes a sealing ring stack and a second support ring 6 disposed at the outer end of the sealing ring stack. The second support ring 6 is provided with a mud and sand discharge hole 8 connecting its inner and outer sides. It also includes an inner ring 5 and an outer ring 7, both of which are flexible rings. The inner side of the second support ring 6 is provided with an inner flange 14 coaxial with it, and the outer side of the second support ring 6 is provided with an outer flange 15 coaxial with it. The inner ring 5 is disposed inside the second support ring 6 and sandwiched between the outer end of the sealing ring stack and the inner flange 14. The outer ring 7 is disposed outside the second support ring 6 and sandwiched between the outer end of the sealing ring stack and the outer flange 15.

[0049] The inner ring 5 protrudes relative to the inner flange 14, and the mud and sand outlet hole 8 is located on the outer side of the inner ring 5.

[0050] In the prior art, the sealing ring stack used for turbine blade seals is a stacked structure formed by overlapping multiple sealing rings. In turbine blade seals, X-type sealing rings 3 and V-type sealing rings are usually stacked, and support rings located at both ends of the sealing ring stack are also commonly used. The support rings are used to transmit compressive force to the sealing ring stack to constrain the sealing ring stack so that the inner side is sealed to the blade shaft 10 and the outer side is sealed to the channel on the runner body 13.

[0051] The above structural forms are common implementations of turbine blade sealing assemblies. This solution addresses the issue that turbine blade sealing assemblies may be used in water bodies containing a large amount of silt. During long-term operation, this silt may enter between the sealing ring stack and the blade shaft 10. For turbines with adjustable blades (such as axial-flow propeller turbines), when the blade angle is adjusted, this silt will become abrasive particles located between the blade shaft 10 and the sealing ring stack during blade rotation, accelerating the damage to the surface of the blade shaft 10 and the inner side of the sealing ring stack. A technical solution is proposed that a silt outlet hole 8 is set on the second support ring 6, and an inner ring 5 and an outer ring 7 are set between the silt outlet hole 8 and the sealing ring stack.

[0052] Specifically, the second support ring 6 is a support ring that acts on the outer end of the sealing ring stack. In practical application, the outer end of the second support ring 6 interacts with the pressure plate 12 installed on the impeller body 13. When the silt in the water enters the gap between the pressure plate 12 and the blade shaft 10 through the gap between the pressure plate 12 and the blade shaft 10, the inner ring 5 protruding relative to the inner flange 14 acts as a retaining ring for the silt to move further into the sealing ring stack. Under the centrifugal force generated by the rotation of the impeller body 13, the silt is discharged through the silt outlet hole 8 located inside the second support ring 6 and through the silt outlet hole 8 located outside the second support ring 6. Therefore, this solution uses the inner ring 5 to act as a barrier to prevent silt from further penetrating into the sealing ring stack. If it cannot completely prevent silt from penetrating, the silt outlet hole 8 reduces the concentration of silt particles at the sealing component 9. This reduces the damage caused by silt in the water to the blade shaft 10 and the sealing ring stack on the sealing component 9 when the blade rotates.

[0053] The inner flange 14 and outer flange 15 can be annular structures integrally formed with the second support ring 6 and located on the inner and outer sides of the second support ring 6, respectively. Alternatively, they can be annular structures welded or snapped onto the inner and outer sides of the second support ring 6. Their function is to allow the second support ring 6 to provide pressure towards the inner end of the sealing ring stack for the inner ring 5 and outer ring 7, respectively. This pressure forces the inner ring 5 and outer ring 7 to deform and constrain their axial position on the second support ring 6, ensuring that the inner ring 5 and outer ring 7 effectively prevent sediment from moving further towards the sealing ring stack. Since the second support ring 6 is typically configured with an inner diameter larger than the outer diameter of the impeller shaft 10 and an outer diameter smaller than the diameter of the hole (shaft hole) on the impeller body 13, the outer ring 7, in conjunction with the inner ring 5, is used to balance the pressure exerted by the inner and outer sides of the second support ring 6 on the sealing ring stack.

[0054] Example 2:

[0055] This embodiment is a further refinement of embodiment 1:

[0056] The inner ring 5 has the following dimensions: it can fit with the turbine blade shaft 10 to form an annular contact line or contact surface under the compression of the inner flange 14 and the sealing ring stack.

[0057] The outer ring 7 has the following dimensions: it can fit with the turbine runner 13 to form an annular contact line or contact surface under the compression of the outer flange 15 and the sealing ring stack.

[0058] The inner ring 5 and the outer ring 7 are located at the same axial position as the second support ring 6;

[0059] In its natural state, the inner ring 5 and the outer ring 7 have the same thickness.

[0060] The above scheme is as follows: the inner ring 5 is sized to ensure that its inner side fits well with the side of the impeller shaft 10 under corresponding compression, and the outer ring 7 is sized to ensure that its outer side fits well with the surface of the channel on the impeller body 13 under corresponding compression. This effectively prevents mud and sand from entering between the sealing ring stack and the impeller shaft 10 and causing abrasive wear, as well as from accumulating in the cavity of the sealing ring stack, thus affecting the deformation of the sealing ring stack under pressure adaptation. The same axial position and equal thickness design are intended to ensure that the inner and outer sides of the second support ring 6 can provide balanced support for the sealing ring stack.

[0061] Example 3:

[0062] This embodiment is a further refinement of embodiment 1:

[0063] The number of mud and sand outlet holes 8 is multiple, and the mud and sand outlet holes 8 are evenly arranged in the circumferential direction of the second support ring 6.

[0064] The above scheme can effectively ensure the discharge of mud and sand at various positions inside the second support ring 6.

[0065] Example 4:

[0066] This embodiment is a further refinement of embodiment 1:

[0067] The sealing ring stack includes a first stack 2, an X-shaped sealing ring 3, and a second stack 4 stacked sequentially from the inner end to the outer end. The first stack 2 and the second stack 4 are both stacked structures formed by stacking two or more V-shaped sealing rings.

[0068] The recessed side of the first stack 2 faces the inner end of the turbine blade sealing assembly, and the recessed side of the second stack 4 faces the outer end of the turbine blade sealing assembly.

[0069] It also includes a first support ring 1 that mates with the inner end of the first stack 2, and the outer end of the first support ring 1 is embedded in the groove at the end of the first stack 2;

[0070] The inner end of the second support ring 6 is embedded in the groove at the end of the second stack 4.

[0071] The above provides a specific implementation of the sealing ring stack, which uses X-type sealing rings 3 and V-type sealing rings to form the sealing ring stack, thereby creating multiple sealing lips. Each sealing lip can adapt to the contact pressure of the sealing surface through deformation under the pressure difference on both sides, providing a reliable sealing solution with low resistance to the rotation of the blade shaft 10. The first support ring 1 is the support ring at the inner end of the sealing ring stack, working in conjunction with the second support ring 6 to transmit the compressive force on the sealing ring stack and stabilize the position of the sealing ring stack in the radial direction of the blade shaft 10.

[0072] Example 5:

[0073] This embodiment is a further refinement of embodiment 4:

[0074] The V-shaped sealing ring on the first stack 2 is a nitrile rubber ring, and the V-shaped sealing ring and X-shaped sealing ring 3 on the second stack 4 are both polyurethane rings.

[0075] In the above scheme, the first layer 2 is the sealing ring structure near the oil side during use, and the second layer 4 is the sealing ring structure near the water side during use. The X-shaped sealing ring 3 is the sealing ring structure in the middle position. Using this scheme, the first layer 2 is more likely to come into contact with oil. Using a nitrile rubber ring as the V-shaped sealing ring at this position can effectively prevent oil from affecting the long-term reliability of the first layer 2. The second layer 4 is more likely to come into contact with water. Using a polyurethane ring as the V-shaped sealing ring at this position can effectively prevent water from affecting the long-term reliability of the second layer 4 (nitrile rubber has excellent oil resistance, but it is prone to expansion and aging after long-term contact with water; polyurethane is more susceptible to water damage after long-term contact with mineral oil). Contact is prone to swelling and softening, losing structural stability and elasticity, while exhibiting excellent hydrolysis resistance. Meanwhile, the V-shaped sealing ring on the second stack 4 at the outer end of the sealing ring stack, due to its polyurethane ring, can ensure its service life when in contact with mud and sand through wear resistance far superior to that of nitrile rubber rings. It also has strong resistance to possible cavitation cavitation and ideal surface stability. At the same time, the X-shaped sealing ring 3 is set as a polyurethane ring, which aims to utilize the better structural stability of the X-shaped sealing ring 3 compared to the V-shaped sealing ring, and to utilize the strong dynamic sealing ability of the polyurethane ring to ensure the sealing reliability of the turbine blade sealing assembly under blade angle adjustment conditions.

[0076] Example 6:

[0077] This embodiment is a further refinement of embodiment 4:

[0078] The overlapping V-shaped sealing rings satisfy the following condition: the outer convex side of one V-shaped sealing ring is consistent with the outer concave side of the other V-shaped sealing ring, and a mutually overlapping fit is formed through the outer convex side and the concave side.

[0079] The outer end of the first support ring 1 and the inner end of the second support ring 6 are both embedded in the corresponding recesses of the V-shaped sealing ring. The outer end of the first support ring 1 and the inner end of the second support ring 6 both satisfy the following: during the process of embedding into the recess, the compression position of the V-shaped sealing ring first occurs at the inner and outer positions of the recess.

[0080] In the above scheme, the V-shaped sealing rings are seamlessly fitted together, thus providing a sealing ring stack with a stable stacking relationship. The relationship between the outer end of the first support ring 1 and the inner end of the second support ring 6 and the corresponding V-shaped sealing ring is as follows: when the first support ring 1 and the second support ring 6 compress the corresponding V-shaped sealing ring, the compression position first occurs on the inner and outer sides of the depression. As the V-shaped sealing ring deforms, the compression position gradually moves towards the center of the depression. This provides a technical solution in which, under a small pre-tightening force, the first support ring 1 and the second support ring 6 at both ends can effectively increase the radial deformation of the sealing ring stack when pre-tightening the turbine blade sealing assembly.

[0081] Example 7:

[0082] This embodiment is a further refinement of embodiment 1:

[0083] Both the inner ring 5 and the outer ring 7 are polyurethane rings.

[0084] Similar to Example 5 above, the inner ring 5 and the outer ring 7 are set as polyurethane rings in order to utilize the hydrolysis resistance, wear resistance and cavitation resistance of polyurethane rings.

[0085] Example 8:

[0086] This embodiment is a further refinement of embodiment 1:

[0087] Multiple sealing lips are provided on both the inner and outer sides of the sealing ring stack, arranged at intervals along the axis of the sealing ring stack, and the surface of each sealing lip is a smooth arc surface.

[0088] In the above scheme, the surface shape of the arc-shaped sealing lip is used to avoid stress concentration on the sealing lip, which would affect the long-term performance stability of the sealing lip.

[0089] Example 9:

[0090] Based on Embodiment 1, this embodiment provides a water turbine, including a runner body 13 and a blade shaft 10 that cooperates with the runner body 13, and also includes a sealing assembly 9 disposed between the runner body 13 and the blade shaft 10 by a pressure plate 12. The sealing assembly 9 is the water turbine blade sealing assembly described in Embodiment 1.

[0091] A mud and sand discharge cavity 11 is formed between the pressure plate 12 and the wheel body 13. The mud and sand discharge cavity 11 communicates with the mud and sand discharge hole 8 located on the outside of the second support ring 6. The mud and sand discharge cavity 11 extends to the outer surface of the wheel body 13.

[0092] This turbine is a turbine including the turbine blade sealing assembly, and represents a specific application of the aforementioned turbine blade sealing assembly. In this design, the sediment discharge chamber 11 serves as a channel for sediment to pass through the sediment discharge hole 8 and move from the inside of the second support ring 6 to the outside of the runner body 13.

[0093] Example 10:

[0094] This embodiment is a further refinement of embodiment 9:

[0095] The hole on the rotor body 13 for installing the sealing component 9 is a stepped hole with an outer diameter larger than the inner diameter. The inner end face of the sealing component 9 is supported on the stepped surface at the end of the stepped hole. The mud and sand discharge hole 8 is located on the outside of the second support ring 6 and is located in the area enclosed by the outer section of the stepped hole.

[0096] The above solution provides a specific form of setting a turbine blade sealing assembly on the runner body 13. Specifically, a cavity surrounding the second support ring 6 is formed by the outer section of the stepped hole to increase the width of the outer cavity of the second support ring 6, so that the mud and sand can be discharged from the mud and sand outlet hole 8, then through the mud and sand outlet cavity 11, and finally discharged from the outer surface of the runner body 13.

[0097] 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 hydro turbine blade seal assembly comprising a seal ring stack and a second support ring (6) arranged at the outer end of the seal ring stack, characterized in that The second support ring (6) is provided with a silt guide hole (8) communicating with the inside and outside of the second support ring (6), and further comprises an inner ring (5) and an outer ring (7) which are both flexible rings, the inside of the second support ring (6) is provided with an inside flange (14) coaxial with the second support ring (6), the outside of the second support ring (6) is provided with an outside flange (15) coaxial with the second support ring (6), the inner ring (5) is arranged on the inside of the second support ring (6) and clamped between the outer end of the sealing ring stack and the inside flange (14), and the outer ring (7) is arranged on the outside of the second support ring (6) and clamped between the outer end of the sealing ring stack and the outside flange (15). The inner ring (5) protrudes relative to the inside flange (14), and the silt guide hole (8) is located on the outside of the inner ring (5).

2. The hydro turbine paddle seal assembly of claim 1, wherein, The size of the inner ring (5) satisfies that the inner ring (5) can be in contact with the blade shaft (10) of the water turbine to form an annular contact line or contact surface under the extrusion of the inside flange (14) and the sealing ring stack. The size of the outer ring (7) satisfies that the outer ring (7) can be in contact with the runner body (13) of the water turbine to form an annular contact line or contact surface under the extrusion of the outside flange (15) and the sealing ring stack. The inner ring (5) and the outer ring (7) are arranged at the same axial position of the second support ring (6). The inner ring (5) and the outer ring (7) are equal in thickness in the natural state.

3. The hydro turbine paddle seal assembly of claim 1, wherein, The number of the silt guide holes (8) is multiple, and the silt guide holes (8) are uniformly arranged in the circumferential direction of the second support ring (6).

4. The hydro turbine paddle seal assembly of claim 1, wherein, The sealing ring stack comprises a first stack (2), an X-shaped sealing ring (3) and a second stack (4) which are sequentially stacked from the inner end to the outer end, and the first stack (2) and the second stack (4) are both stack structures formed by stacking two or more V-shaped sealing rings. The recessed side of the first stack (2) faces the inner end of the water turbine blade sealing assembly, and the recessed side of the second stack (4) faces the outer end of the water turbine blade sealing assembly. Further comprising a first support ring (1) matched with the inner end of the first stack (2), and the outer end of the first support ring (1) is embedded in the groove of the end of the first stack (2). The inner end of the second support ring (6) is embedded in the groove of the end of the second stack (4).

5. The hydro turbine paddle seal assembly of claim 4, wherein, The V-shaped sealing ring on the first stack (2) is a nitrile rubber ring, and the V-shaped sealing ring on the second stack (4) and the X-shaped sealing ring (3) are both polyurethane rings.

6. The hydro turbine paddle seal assembly of claim 4, wherein, The mutually stacked V-shaped sealing rings satisfy that the outer convex side of one V-shaped sealing ring is consistent with the shape of the recessed side of another V-shaped sealing ring, and the mutually stacked V-shaped sealing rings are in a fitting relationship through the outer convex side and the recessed side. The outer end of the first support ring (1) and the inner end of the second support ring (6) are both embedded in the recess of the corresponding V-shaped sealing ring, and the outer end of the first support ring (1) and the inner end of the second support ring (6) both satisfy that the extrusion position of the V-shaped sealing ring first occurs at the inner side position and the outer side position of the recess during the embedding process.

7. The turbine bucket seal assembly of any one of claims 1 to 6, wherein, The inner ring (5) and the outer ring (7) are both polyurethane rings.

8. The hydro turbine paddle seal assembly of any one of claims 1 to 6, wherein, The inner side and the outer side of the sealing ring stack are both provided with multiple sealing lips which are arranged at intervals along the axis of the sealing ring stack, and the surface of each sealing lip is a smooth arc surface.

9. Hydraulic turbine comprising a runner body (13) and a paddle shaft (10) cooperating with the runner body (13), further comprising a sealing assembly (9) arranged between the runner body (13) and the paddle shaft (10) by means of a pressure plate (12), characterized in that, The sealing assembly (9) is a water turbine blade sealing assembly according to any one of claims 1 to 8. The pressing plate (12) and the runner body (13) form a sediment guiding cavity (11), which communicates with the orifice of the sediment guiding hole (8) on the outer side of the second supporting ring (6), and the sediment guiding cavity (11) extends to the outer surface of the runner body (13).

10. The hydraulic turbine of claim 9, wherein The hole for mounting the sealing assembly (9) on the runner body (13) is a stepped hole with the outer section diameter being larger than the inner section diameter, the inner end surface of the sealing assembly (9) is supported on the stepped surface at the end of the stepped hole, and the orifice of the sediment guiding hole (8) on the outer side of the second supporting ring (6) is located in the area surrounded by the outer section of the stepped hole.

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