Combined turbulent flow steam seal structure
By adding spoiler rings and spoiler grooves in the toothed maze seal structure of high-pressure steam turbines to hinder and reduce the speed of steam circulation, the problem of out-of-control vibration of the rotor shaft is solved and effective vibration control is achieved.
Patent Information
- Application Number
- CN202323644887.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-29
- Publication Date
- 2025-02-21
- Estimated Expiration
- 2033-12-29
AI Technical Summary
In high-pressure steam turbines, the rotor shaft is prone to vibration out of control when rotating at high speed. The reason is that the high-pressure steam circulation is formed between the static sealing teeth and the dynamic sealing teeth, resulting in an increase in the half-speed vibration energy, which is more likely to lead to instability when the frequency fits.
The toothed maze seal structure adds a spoiler ring and a spoiler groove. The outer circular side of the spoiler ring is connected to the inner wall of the stator. The rotor shaft passes through the shaft hole in the middle of the spoiler ring, and a first spoiler is arranged on the spoiler ring. The sheet and the second spoiler, the first spoiler, is spiral-torque, and the spoiler is arranged irregularly alone or in combination on the inner wall of the stator.
Through the design of the spoiler ring and the spoiler groove, the rotation speed of the steam circulation is hindered, forming a vortex current reduces the average speed of the steam circulation, destroying its stability, thereby preventing the rotor shaft from vibrating out of control at high speed rotation.
Smart Images
Figure CN222513522U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the field, and more specifically relates to a combined spoiler steam seal structure in a high-pressure steam turbine. Background Art
[0002] In high-pressure and ultra-high-pressure steam turbines or industrial turbines, in order to reduce leakage losses, a dense tooth-shaped labyrinth seal structure is often used for sealing in the high-pressure section. The tooth-shaped labyrinth seal structure consists of static sealing teeth on the stator and dynamic sealing teeth on the rotor shaft. The sealing section of the sealing structure is long, and the sealing distance between the static sealing teeth and the dynamic sealing teeth is small. The length of the rotor shaft is usually long and its rotation speed is high. Therefore, it is inevitable that the rotor rigidity deteriorates, making the rotor shaft prone to instability during rotation.
[0003] At the same time, due to the high energy density of high-pressure and ultra-high-pressure steam, when the high-pressure steam flows into the labyrinth seal structure, driven by the high-speed rotation of the rotor shaft, it is easy to form a high-speed rotating steam circulation in the narrow area between the static sealing teeth and the dynamic sealing teeth. The rotation direction of the steam circulation is the same as the rotation direction of the rotor shaft, and its average angular velocity is approximately half of the rotor shaft speed. The greater the energy density of the steam circulation, the greater the half-speed excitation energy it generates. When the periodic vibration frequency generated by this high-energy steam circulation matches the frequency of the rotor shaft, it is more likely to cause the rotor shaft with poor rigidity to become unstable, causing the vibration value of the rotor shaft to continue to increase and become difficult to control, thereby affecting the normal operation of the turbine.
[0004] Therefore, reducing the rotation speed of the high-pressure steam circulation as much as possible is an effective way to avoid uncontrolled rotor shaft vibration. Utility Model Content
[0005] In view of the shortcomings of the prior art, the utility model provides a combined spoiler steam seal structure used in a high-pressure steam turbine. A spoiler ring and a spoiler groove are added to the toothed labyrinth seal structure, which can effectively destroy the stability of the steam circulation and reduce the speed of the steam circulation, thereby preventing the rotor shaft from vibrating out of control under high-speed rotation.
[0006] To achieve the above-mentioned purpose, the utility model provides the following technical solutions: a combined spoiler steam seal structure, comprising a stator, a rotating rotor shaft is arranged in the stator, a plurality of dynamic sealing teeth are arranged at intervals on the rotor shaft, a plurality of static sealing teeth are arranged at intervals on the inner wall of the stator, and also comprises a spoiler ring and a spoiler groove located on the inner wall of the stator, the outer circle side of the spoiler ring is connected to the inner wall of the stator, the rotor shaft passes through the axial hole in the middle of the spoiler ring, a plurality of grooves are arranged on the inner circle side of the spoiler ring, and a tooth piece is formed between two adjacent grooves, the tooth piece comprises a first spoiler and a second spoiler, and the groove distance between two adjacent grooves on both sides of the first spoiler is smaller than that of the second spoiler, the first spoiler and the second spoiler are arranged circumferentially at intervals on the spoiler ring, the first spoiler is spirally twisted, a single spoiler groove or a spoiler ring or a combination of a spoiler groove and a spoiler ring is arranged between the static sealing teeth, and the single spoiler groove or the spoiler ring or the combined spoiler groove and the spoiler ring are arranged at irregular intervals.
[0007] Furthermore, the spiral twist angle of the first spoiler is 8°-12°.
[0008] Furthermore, the spoiler groove includes a plurality of waist-shaped grooves, and the plurality of waist-shaped grooves are circumferentially spaced apart on the inner wall of the stator.
[0009] Further, when the spoiler groove is provided alone, it is located between two adjacent static sealing teeth, and the width of the spoiler groove is smaller than the interval between the two static sealing teeth.
[0010] Furthermore, when the annular spoiler is provided alone, it replaces the position of a static sealing tooth and is located between two adjacent dynamic sealing teeth.
[0011] Furthermore, the thickness of the spoiler ring is the same as the thickness of the static sealing teeth.
[0012] Furthermore, when the spoiler groove and the spoiler ring are arranged in combination, the spoiler ring replaces the position of a static sealing tooth and is located between two adjacent dynamic sealing teeth, and spoiler grooves are arranged on both sides of the spoiler ring.
[0013] Compared with the prior art, the utility model has the following beneficial effects: the rotation speed of the steam circulation is hindered from the side by the first spoiler twisted at a certain angle and the wider and straighter second spoiler, and the spoiler grooves on the inner wall of the stator can form eddies at the outer edges of the steam circulation to further reduce the average speed of the steam circulation, and the spoiler rings and spoiler grooves are irregularly arranged on the stator alone or in combination, which effectively destroys the stability of the steam circulation and reduces the speed of the steam circulation, thereby preventing the rotor shaft from vibrating out of control under high-speed rotation. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1It is a schematic diagram of the combined spoiler steam seal structure of the utility model;
[0015] Figure 2 It is a structural schematic diagram of the spoiler ring in the combined spoiler steam seal structure of the utility model (the first spoiler is in an untwisted state).
[0016] Reference numerals: stator 1 ; rotor shaft 2 ; dynamic sealing teeth 3 ; static sealing teeth 4 ; spoiler ring 5 ; spoiler groove 6 ; groove 7 ; first spoiler vane 8 ; second spoiler vane 9 . DETAILED DESCRIPTION
[0017] In the description of the present invention, it should be noted that directional words, such as the terms "center", "lateral (X)", "longitudinal (Y)", "vertical (Z)", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", etc., indicating directions and positional relationships are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of narrating the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and cannot be understood as limiting the specific protection scope of the present invention.
[0018] In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features. Therefore, the definition of "first" and "second" features can explicitly or implicitly include one or more of the features. In the description of the utility model, the meaning of "several" and "a number" is two or more, unless otherwise clearly and specifically defined.
[0019] Reference Figure 1 and Figure 2 The utility model is further described.
[0020] A combined turbulent steam seal structure comprises a stator 1, wherein a rotating rotor shaft 2 is arranged in the stator 1, a plurality of dynamic sealing teeth 3 arranged at intervals are arranged on the rotor shaft 2, a plurality of static sealing teeth 4 arranged at intervals are arranged on the inner wall of the stator 1, a tooth-shaped labyrinth seal structure is formed between the dynamic sealing teeth 3 and the static sealing teeth 4, and further comprises a turbulent ring 5 and a turbulent groove 6 located on the inner wall of the stator 1, the outer circumference of the turbulent ring 5 is connected to the inner wall of the stator 1, the rotor shaft 2 passes through the axial hole in the middle of the turbulent ring 5, and the inner circumference of the turbulent ring 5 is provided with A plurality of grooves 7 are provided, and tooth plates are formed between two adjacent grooves 7. The tooth plates include a first spoiler plate 8 and a second spoiler plate 9. The groove pitch between two adjacent grooves 7 on both sides of the first spoiler plate 8 is smaller than that of the second spoiler plate 9. The first spoiler plate 8 and the second spoiler plate 9 are circumferentially spaced apart on the spoiler ring 5. The first spoiler plate 8 is spirally twisted. A single spoiler groove 6 or a spoiler ring 5 or a combination of a spoiler groove 6 and a spoiler ring 5 is provided between the static sealing teeth 4, and the single spoiler groove 6 or the spoiler ring 5 or the combined spoiler groove 6 and the spoiler ring 5 are irregularly spaced apart.
[0021] This is a preferred embodiment, wherein the spiral twist angle of the first spoiler 8 is 8°-12°, and specifically may be 10°.
[0022] like Figure 1 As shown, in this embodiment, preferably, the spoiler groove 6 includes a plurality of waist-shaped grooves, and the plurality of waist-shaped grooves are circumferentially spaced apart on the inner wall of the stator 1 .
[0023] Preferably, in this embodiment, when the spoiler groove 6 is provided alone, it is located between two adjacent static sealing teeth 4 , and the width of the spoiler groove 6 is smaller than the interval between the two static sealing teeth 4 .
[0024] like Figure 1 As shown, in this embodiment, preferably, when the annular spoiler is provided alone, it replaces the position of a static sealing tooth 4 and is located between two adjacent dynamic sealing teeth 3 .
[0025] like Figure 1 As shown, in this embodiment, preferably, the thickness of the spoiler ring 5 is the same as the thickness of the static sealing tooth 4 .
[0026] like Figure 1 As shown, in this embodiment, preferably, when the spoiler groove 6 is combined with the spoiler ring 5 , the spoiler ring 5 replaces the position of a static sealing tooth 4 and is located between two adjacent dynamic sealing teeth 3 , and spoiler grooves 6 are provided on both sides of the spoiler ring 5 .
[0027] like Figure 1 and Figure 2As shown, the rotation speed of the steam circulation is hindered from the side by the first spoiler 8 twisted at a certain angle and the wider and straight second spoiler 9, and the spoiler groove 6 on the inner wall of the stator 1 can form a vortex at the outer edge of the steam circulation to further reduce the average speed of the steam circulation, and the spoiler ring 5 and the spoiler groove 6 are irregularly arranged on the stator 1 alone or in combination, which effectively destroys the stability of the steam circulation and reduces the speed of the steam circulation, thereby preventing the rotor shaft 2 from vibrating out of control under high-speed rotation.
[0028] The above is only a preferred embodiment of the present invention. The protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.
Claims
1. A combined spoiler steam seal structure, comprising a stator, a rotating rotor shaft is arranged inside the stator, a plurality of dynamic sealing teeth are arranged at intervals on the rotor shaft, and a plurality of static sealing teeth are arranged at intervals on the inner wall of the stator, characterized in that: The invention also includes a spoiler ring and a spoiler groove on the inner wall of the stator, the outer circle side of the spoiler ring is connected to the inner wall of the stator, the rotor shaft passes through the axial hole in the middle of the spoiler ring, a plurality of grooves are arranged on the inner circle side of the spoiler ring, and tooth plates are formed between two adjacent grooves, the tooth plates include a first spoiler plate and a second spoiler plate, and the groove distance between two adjacent grooves on both sides of the first spoiler plate is smaller than that of the second spoiler plate, the first spoiler plate and the second spoiler plate are circumferentially spaced apart on the spoiler ring, the first spoiler plate is spirally twisted, a separate spoiler groove or a spoiler ring or a combination of a spoiler groove and a spoiler ring is arranged between the static sealing teeth, and the separate spoiler groove or the spoiler ring or the combined spoiler groove and the spoiler ring are arranged at irregular intervals.
2. The combined spoiler steam seal structure according to claim 1 is characterized in that: The spiral twist angle of the first spoiler is 8°-12°.
3. The combined spoiler steam seal structure according to claim 2 is characterized in that: The spoiler groove comprises a plurality of waist-shaped grooves, and the plurality of waist-shaped grooves are arranged on the inner wall of the stator at intervals in the circumferential direction.
4. The combined spoiler steam seal structure according to claim 3 is characterized in that: When the spoiler groove is provided alone, it is located between two adjacent static sealing teeth, and the width of the spoiler groove is smaller than the interval between the two static sealing teeth.
5. The combined spoiler steam seal structure according to claim 4 is characterized in that: When the annular spoiler is provided alone, it replaces the position of a static sealing tooth and is located between two adjacent dynamic sealing teeth.
6. The combined spoiler steam seal structure according to claim 5 is characterized in that: The thickness of the spoiler ring is the same as the thickness of the static sealing teeth.
7. The combined spoiler steam seal structure according to claim 6 is characterized in that: When the spoiler groove and the spoiler ring are arranged in combination, the spoiler ring replaces the position of a static sealing tooth and is located between two adjacent dynamic sealing teeth. The spoiler grooves are arranged on both sides of the spoiler ring.