High-low tooth sealing structure with adaptive capability

Abstract

The application relates to a high-low tooth sealing structure with self-adaptive capability, and relates to the technical field of mechanical sealing, which comprises a rotor, a supporting main body, and a stator sealing ring, the supporting main body is used for supporting the rotor and is rotationally connected with the rotor, the stator sealing ring is sleeved on the outer rotor and is fixedly connected with the supporting main body, a sealing tooth groove is formed in the circumferential wall of the rotor, and at least two sealing tooth grooves are spaced apart in the axial direction of the rotor; a plurality of low teeth and a plurality of high teeth are circumferentially formed on the inner circumferential wall of the stator sealing ring, the low teeth and the high teeth are alternately arranged in the axial direction of the stator sealing ring, a gap is left between the low teeth and the rotor, the high teeth extend into the corresponding sealing tooth groove, and a gap is left between the high teeth and the sealing tooth groove, and the circumferential wall surface of the rotor and the surface of the sealing tooth groove are both provided with an abradable material layer. The application has the effects of reducing the damage caused by the collision and abrasion between the rotor and the stator to the sealing performance and improving the recovery after abrasion.

Description

Technical Field

[0001] This application relates to the field of mechanical seal technology, and in particular to a high-low tooth seal structure with adaptive capability. Background Technology

[0002] High-low tooth seals, also known as labyrinth seals, are a type of non-contact fluid dynamic seal widely used in turbine machinery. Their basic principle is to utilize a series of alternating high and low teeth to form a narrow throttling gap with the corresponding sealing bushing. This causes a series of throttling expansion effects as fluid passes through, thereby reducing the pressure and flow rate of the leaking medium and achieving a seal.

[0003] In traditional high-low tooth seal structures, the gap between the sealing teeth and the bushing is fixed during unit installation. During unit startup, shutdown, or changes in operating conditions, the rotor and stator undergo relative displacement (e.g., thermal expansion, vibration), potentially altering the design gap. If the gap is too small, frictional wear can easily occur, even leading to rotor thermal bending; if the gap is too large, the sealing effect significantly decreases, resulting in reduced efficiency. However, even slight contact can cause the sealing tooth tips to wear, permanently increasing the gap and permanently degrading the sealing performance, making repair difficult. While adjustable seals exist in existing technologies, their structures are often very complex, costly, and their reliability is difficult to guarantee, making them unsuitable for high-speed rotating machinery. Utility Model Content

[0004] In order to reduce the damage to the sealing performance caused by the friction between the rotor and the stator and improve the recovery after wear, this application provides a high and low tooth sealing structure with adaptive capability.

[0005] The adaptive high-low tooth sealing structure provided in this application adopts the following technical solution: An adaptive high-low tooth sealing structure includes a rotor, a support body, and a stator sealing ring. The support body supports the rotor and is rotatably connected to it. The stator sealing ring is sleeved on the outside of the rotor and fixedly connected to the support body. The rotor's circumferential wall has sealing grooves, with at least two sealing grooves spaced apart along the rotor's axial direction. The inner circumferential wall of the stator sealing ring is circumferentially formed with a plurality of low teeth and a plurality of high teeth, which are alternately arranged along the axial direction of the stator sealing ring. A gap is left between the low teeth and the rotor. Each high tooth corresponds to a sealing groove and extends into the corresponding sealing groove, leaving a gap between the high tooth and the sealing groove. A wear-resistant material layer is provided on the surface of the rotor's circumferential wall and the surface of the sealing groove.

[0006] By adopting the above technical solution, the high teeth extend into the sealing tooth groove of the rotor, and together with the low teeth arranged alternately there, form a multi-stage tortuous sealing path, improving the throttling effect. Under normal operating conditions, the support body keeps the stator sealing ring in a position with the initial design clearance from the rotor, achieving optimal sealing. When the rotor shifts in a certain direction due to thermal expansion, vibration, or gravitational bending, the high and low teeth in that direction will be subjected to aerodynamic pressure or slight contact from the rotor's proximity. At this time, slight friction will occur between the sealing tooth groove and the high teeth, and between the rotor peripheral wall and the low teeth, meaning a small amount of the wear-resistant material layer will be worn away, but it will be essentially undamaged. After unavoidable slight friction, the wear-resistant material layer protects the rotor and the high and low tooth bases, maintaining a small effective operating clearance even after wear, achieving adaptive maintenance of sealing performance. Furthermore, the worn wear-resistant material layer is easy to restore at a low cost, while the expensive and difficult-to-repair rotor and stator sealing ring are protected. This reduces the damage to the sealing performance caused by rotor-stator friction and improves the recoverability after wear.

[0007] Preferably, the sealing groove is rectangular in shape within the radial section, wherein the radial section is the plane where the rotor axis is located.

[0008] By adopting the above technical solution, the rectangular tooth groove structure is simple and easy to process. When combined with the high tooth, it forms clear radial and axial limits, improving the stability and reliability of the seal. In addition, the rectangular tooth groove has fewer corner areas, making it easier to repair the wearable material layer.

[0009] Preferably, both the high teeth and the low teeth are triangularly arranged in the radial section, wherein the radial section is the plane where the rotor axis is located.

[0010] By adopting the above technical solution, the cross-sections of the high teeth and the low teeth are triangular. The angle of the tooth tip of the triangular tooth shape is easy to run into the wearable material layer. Moreover, when there is slight contact, the worn part of the wearable material layer forms a triangle that matches the tooth tip, which makes it easier to form a more fitting dynamic sealing surface.

[0011] Preferably, the support body includes a support element and a stator sleeve. The support element is used to support the rotor and is rotatably connected to the rotor. One end of the stator sleeve is fixedly connected to the support element, and the other end of the stator sleeve is provided with a positioning groove. The axis of the positioning groove coincides with the rotor axis. The stator sealing ring is located in the positioning groove, and the outer peripheral wall of the stator sealing ring abuts against the inner peripheral wall of the positioning groove.

[0012] By adopting the above technical solution, the support element provides positioning for the stator sleeve, and the stator sleeve and positioning groove provide a radial installation reference for the stator sealing ring, ensuring that the initial gap between it and the rotor is uniform and consistent, which is conducive to achieving the best sealing effect.

[0013] Preferably, the stator sealing ring comprises two symmetrically divided semi-rings.

[0014] By adopting the above technical solution, the symmetrically segmented split half ring is easy to install and replace, prevents the sealing groove and high tooth from interfering with the disassembly of the stator sealing ring, facilitates the repair of the wearable material layer, and improves maintenance efficiency.

[0015] Preferably, the positioning groove has a limiting part integrally formed at one end near the support element, one end of the stator sealing ring abuts against the limiting part, and the end of the stator sleeve away from the support element is detachably connected to an end cap via a connector, the end cap abutting against the other end of the stator sealing ring.

[0016] By adopting the above technical solution, the limiting part and the end cover together form an axial fixing structure for the stator sealing ring, preventing the stator sealing ring from moving during operation. At the same time, the end cover is detachable, which facilitates the disassembly and assembly of the sealing ring.

[0017] Preferably, the connector is a bolt.

[0018] By adopting the above technical solutions, bolted connections have the advantages of simple structure, high reliability, and adjustable preload, making them convenient for on-site assembly and maintenance.

[0019] Preferably, the wearable material layer is a graphite-based composite coating.

[0020] By adopting the above technical solutions, the graphite-based composite coating exhibits superior self-lubricating properties. When the high and low teeth slightly rub against the rotor, it reduces the coefficient of friction, preventing tooth tip damage from meshing with the rotor substrate. Simultaneously, the graphite-based composite coating possesses excellent high-temperature resistance and corrosion resistance, and is not prone to aging or failure over long-term use. Furthermore, the graphite-based composite coating is soft and highly malleable, quickly forming a highly conformable dynamic sealing surface with the tooth tips after wear, maintaining an effective sealing gap. Its material cost is low, and the application and repair process is simple, reducing maintenance costs.

[0021] In summary, this application includes at least one of the following beneficial technical effects: 1. By setting up a rotor, support body, stator sealing ring, sealing tooth groove, low tooth, high tooth, and wearable material layer, when the rotor deviates and causes slight friction, the wearable material layer can adaptively wear down to maintain a small effective operating gap, protect the rotor and the base of the sealing teeth, achieve adaptive maintenance of sealing performance, and significantly reduce the repair cost and difficulty after wear. 2. By setting support elements, stator sleeves, and positioning grooves, a radial installation reference and positioning are provided for the stator sealing ring, ensuring the uniformity and stability of the initial sealing gap between the stator sealing ring and the rotor; 3. By setting limit parts, end caps, and bolts, reliable axial fixation of the stator sealing ring is achieved, preventing the stator sealing ring from moving during operation. At the same time, the detachable connection of the bolts facilitates the installation, disassembly, and maintenance of the stator sealing ring, improving the practicality and ease of maintenance of the structure. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the radial section of a high-low tooth sealing structure with adaptive capability provided in the embodiments of this application.

[0023] Figure 2 yes Figure 1 Enlarged view of section A.

[0024] Explanation of reference numerals in the attached drawings: 1. Rotor; 11. Sealing tooth groove; 12. Wearable material layer; 2. Support body; 21. Support element; 22. Stator sleeve; 221. Positioning groove; 222. Limiting part; 23. End cover; 24. Bolt; 3. Stator sealing ring; 31. Low tooth; 32. High tooth. Detailed Implementation

[0025] The following is in conjunction with the appendix Figure 1-2 This application will be described in further detail.

[0026] This application discloses a high-low tooth sealing structure with adaptive capability. (Refer to...) Figure 1 It includes a rotor 1, a support body 2, and a stator sealing ring 3. The support body 2 supports the rotor 1 and is rotatably connected to the rotor 1. The stator sealing ring 3 is sleeved on the outside of the rotor 1 and is fixedly connected to the support body 2.

[0027] Reference Figure 1 and Figure 2 The rotor 1 has a sealing groove 11 circumferentially opened on its peripheral wall. At least two sealing grooves 11 are spaced apart in the axial direction of the rotor 1. In this embodiment, there are two sealing grooves 11. The sealing grooves 11 are rectangular in the radial section, where the radial section is the plane where the axis of the rotor 1 is located.

[0028] Reference Figure 1 and Figure 2The inner circumferential wall of the stator sealing ring 3 is circumferentially formed with a plurality of low teeth 31 and a plurality of high teeth 32. The low teeth 31 and high teeth 32 are alternately arranged along the axial direction of the stator sealing ring 3, and a gap is left between the low teeth 31 and the circumferential wall of the rotor 1. The high teeth 32 correspond one-to-one with the sealing tooth grooves 11, and the high teeth 32 extend into the corresponding sealing tooth grooves 11, leaving a gap between them and the sealing tooth grooves 11. Both the high teeth 32 and the low teeth 31 are triangular in shape in the radial section, and the tips of the high teeth 32 and the low teeth 31 face the rotor 1. A wearable material layer 12 is provided on the surface of the circumferential wall of the rotor 1 and the surface of the sealing tooth grooves 11. The wearable material layer 12 is a graphite-based composite coating with a lower strength than that of the rotor 1 and the stator sealing ring 3.

[0029] Reference Figure 1 and Figure 2 The high teeth 32 extend into the sealing tooth groove 11 of the rotor 1 and alternate with the low teeth 31, forming a multi-stage tortuous sealing path, effectively increasing the number of fluid throttling cycles and improving the sealing effect. The wear-resistant material layer 12 of the graphite-based composite coating on the surface of the rotor 1 and the surface of the sealing tooth groove 11 preferentially undergoes adaptive wear when the rotor 1 shifts due to thermal expansion, vibration, etc., and slightly rubs against the tooth tips, thereby maintaining a small effective operating clearance and preventing damage to the rotor 1 substrate and the sealing tooth substrate. After wear, the wear-resistant material layer 12 is easy to repair.

[0030] Reference Figure 1 The support body 2 includes a support element 21 and a stator sleeve 22. The support element 21 supports the rotor 1 and is rotatably connected to the rotor 1. In this embodiment, the support element 21 is a support structure used in turbine machinery to support the rotation of the rotor 1, and is rotatably connected to the rotor 1 through bearings or other means. One end of the stator sleeve 22 is fixedly connected to the support element 21 by screws.

[0031] Reference Figure 1 and Figure 2 The stator sleeve 22 has a positioning groove 221 at its other end, and the axis of the positioning groove 221 coincides with the axis of the rotor 1. The stator sealing ring 3 includes two symmetrically divided semi-rings. After the two semi-rings are combined to form the stator sealing ring 3, they are located in the positioning groove 221, and the outer peripheral wall of the stator sealing ring 3 abuts against the inner peripheral wall of the positioning groove 221. The positioning groove 221 has a limiting part 222 integrally formed at one end near the support element 21. One end of the stator sealing ring 3 abuts against the limiting part 222. The end of the stator sleeve 22 away from the support element 21 is detachably connected to an end cap 23 through a connector, and the end cap 23 abuts against the other end of the stator sealing ring 3. The connector is a bolt 24.

[0032] Reference Figure 1 and Figure 2The stator sleeve 22 provides radial positioning for the stator sealing ring 3 through the positioning groove 221, ensuring the initial clearance between the stator sealing ring 3 and the rotor 1. The limiting part 222 and the end cover 23 connected by bolts 24 press the stator sealing ring 3 from both sides, realizing the axial fixation of the stator sealing ring 3 and preventing the stator sealing ring 3 from moving during operation. This facilitates installation and disassembly, thereby enabling the inspection and repair of the wear-resistant material layer 12 and improving the maintainability of the structure.

[0033] The implementation principle of the adaptive high-low tooth sealing structure in this application embodiment is as follows: the high tooth 32 extends into the sealing tooth groove 11 of the rotor 1, and together with the alternating low teeth 31, forms a multi-level tortuous sealing path, improving the throttling effect. Under normal operating conditions, the support body 2 keeps the stator sealing ring 3 in a position with the initial design gap from the rotor 1, achieving optimal sealing. When the rotor 1 shifts in a certain direction due to thermal expansion, vibration, or gravitational bending, the high tooth 32 and low tooth 31 in that direction will be subjected to aerodynamic pressure or slight contact caused by the rotor 1 approaching. At this time, the sealing tooth groove 11 and the high tooth 32, and the peripheral wall of the rotor 1 and the low tooth 31 will slightly rub against each other, that is, a small amount of wear material layer 12 will be worn away, but it is basically undamaged. After unavoidable minor friction, the wearable material layer 12 protects the rotor 1 and the high-tooth 32 and low-tooth 31 substrates. Even after wear, it can maintain a small effective operating clearance, achieving adaptive maintenance of sealing performance. Furthermore, the worn wearable material layer 12 is easy to restore at a low cost, while the expensive and difficult-to-repair rotor 1 and stator sealing ring 3 are protected. This reduces the damage to the sealing performance caused by friction between the rotor 1 and the stator, and improves the recoverability after wear.

[0034] The above are all preferred embodiments of this application, and are not intended to limit the scope of protection of this application. Therefore, all equivalent changes made in accordance with the structure, shape and principle of this application should be covered within the scope of protection of this application.

Claims

1. A high-low tooth sealing structure with adaptive capability, comprising a rotor (1), a support body (2), and a stator sealing ring (3), wherein the support body (2) supports the rotor (1) and is rotatably connected to the rotor (1), and the stator sealing ring (3) is sleeved on the outside of the rotor (1) and fixedly connected to the support body (2), characterized in that: The rotor (1) has a sealing tooth groove (11) circumferentially formed on its peripheral wall. At least two sealing tooth grooves (11) are spaced apart in the axial direction of the rotor (1). The inner peripheral wall of the stator sealing ring (3) is formed with a plurality of low teeth (31) and a plurality of high teeth (32). The low teeth (31) and high teeth (32) are arranged alternately along the axial direction of the stator sealing ring (3). There is a gap between the low teeth (31) and the rotor (1). The high teeth (32) correspond one-to-one with the sealing tooth grooves (11). The high teeth (32) extend into the corresponding sealing tooth grooves (11) and there is a gap between them and the sealing tooth grooves (11). The peripheral wall surface of the rotor (1) and the surface of the sealing tooth grooves (11) are both provided with a wearable material layer (12).

2. The adaptive high-low tooth sealing structure according to claim 1, characterized in that: The sealing groove (11) is rectangular in shape in the radial section, wherein the radial section is the plane where the axis of the rotor (1) is located.

3. The adaptive high-low tooth sealing structure according to claim 1, characterized in that: The high tooth (32) and the low tooth (31) are both triangularly arranged in the radial section, wherein the radial section is the plane where the axis of the rotor (1) is located.

4. The adaptive high-low tooth sealing structure according to claim 1, characterized in that: The support body (2) includes a support element (21) and a stator sleeve (22). The support element (21) is used to support the rotor (1) and is rotatably connected to the rotor (1). One end of the stator sleeve (22) is fixedly connected to the support element (21), and the other end of the stator sleeve (22) is provided with a positioning groove (221). The axis of the positioning groove (221) coincides with the axis of the rotor (1). The stator sealing ring (3) is located in the positioning groove (221), and the outer peripheral wall of the stator sealing ring (3) abuts against the inner peripheral wall of the positioning groove (221).

5. The adaptive high-low tooth sealing structure according to claim 4, characterized in that: The stator sealing ring (3) comprises two symmetrically divided semi-rings.

6. The adaptive high-low tooth sealing structure according to claim 4, characterized in that: The positioning groove (221) has a limiting part (222) integrally formed at one end near the support element (21). One end of the stator sealing ring (3) abuts against the limiting part (222). The end of the stator sleeve (22) away from the support element (21) is detachably connected to an end cap (23) through a connector. The end cap (23) abuts against the other end of the stator sealing ring (3).

7. The adaptive high-low tooth sealing structure according to claim 6, characterized in that: The connector is a bolt (24).

8. The adaptive high-low tooth sealing structure according to claim 1, characterized in that: The wearable material layer (12) is a graphite-based composite coating.

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