A pressure-compensated seal ring for flexible cutting of a low-pressure cylinder of a steam turbine

Abstract

The utility model discloses a steam turbine low pressure cylinder flexible cutting cylinder pressure compensation type sealing ring, including the transmission shaft, the outer peripheral wall one end of transmission shaft is provided with the fixed ring, still including the compensation subassembly and fixed subassembly of setting in the fixed ring one end, the compensation subassembly includes the flexible ring of fixed intercommunication in the fixed ring one end, the outer peripheral wall fixed connection of flexible ring has extrusion ring, one end fixed intercommunication of extrusion ring has pressure ring, one end sliding connection of pressure ring has the connecting ring, one end fixed connection of connecting ring has the group evenly distributed guide rod, and the outer peripheral wall of each guide rod all is equipped with spring, the utility model discloses through the fixed intercommunication of fixed thread ring one end of thread sleeve, make the spring deformation of thread sleeve one end compression, make the spring drive connecting ring and resist the sliding ring, make the sliding ring movement compression extrusion ring, then extrusion ring deformation compression flexible ring, make flexible ring deformation inwards and fit transmission shaft, realize flexible sealing.

Description

Technical Field

[0001] This utility model relates to the field of flexible sealing technology, and in particular to a pressure-compensated sealing ring for flexible cylinder cutting of a steam turbine low-pressure cylinder. Background Technology

[0002] Steam turbines are core power equipment in thermal power generation, nuclear power generation, and other fields, and their operational efficiency and safety are of paramount importance. During the operation of the low-pressure cylinder of a steam turbine unit, to adapt to different load demands, especially during the winter heating season, a cylinder-cutting operation mode is often adopted, meaning the low-pressure cylinder receives very little or almost no steam. Under this special operating condition, the steam flow rate inside the low-pressure cylinder decreases sharply, and the temperature rises, leading to a deterioration of the sealing environment between the low-pressure cylinder rotor and stationary components.

[0003] Traditional rigid sealing rings have significant drawbacks: under cylinder cutting conditions, rigid sealing rings cannot effectively adapt to the thermal deformation, vibration, and pressure fluctuations that may occur between the rotor and the cylinder. This can easily lead to excessively large sealing gaps causing steam leakage, or insufficient gaps causing friction and wear, and even triggering unit vibration. Leakage reduces unit efficiency, while friction and wear seriously threaten equipment safety and shorten equipment lifespan.

[0004] Therefore, there is an urgent need for a pressure-compensating sealing ring that can maintain a tight seal when the pressure is high, and can adaptively yield when the pressure is low or fluctuates to avoid dry friction, while maintaining a stable sealing effect throughout the process. Utility Model Content

[0005] The purpose of this invention is to address the shortcomings of existing technologies by proposing a pressure-compensated sealing ring for flexible cylinder cutting in steam turbine low-pressure cylinders.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder includes a drive shaft, a fixed ring at one end of the outer peripheral wall of the drive shaft, and a compensation component and a fixing component disposed at one end of the fixed ring.

[0007] The compensation component includes a flexible ring fixedly connected to one end of a fixed ring, a compression ring fixedly connected to the outer peripheral wall of the flexible ring, a pressure ring fixedly connected to one end of the compression ring, a connecting ring slidably connected to one end of the pressure ring, a set of evenly distributed guide rods fixedly connected to one end of the connecting ring, a spring sleeved on the outer peripheral wall of each guide rod, a set of evenly distributed guide holes adapted to the guide rods being opened inside the pressure ring, a fixed threaded ring fixedly connected to the other end of the pressure ring, and a threaded sleeve threadedly connected to one end of the fixed threaded ring.

[0008] Preferably, the outer peripheral wall of the extrusion ring is slidably connected to a sliding ring, and the cross-section of the extrusion ring is arranged in an isosceles trapezoidal structure.

[0009] Preferably, the fixing component includes a set of cavities formed inside the fixing ring, and one end of the fixing ring has a set of air guide holes communicating with the cavities.

[0010] Preferably, a set of uniformly distributed cavities are provided inside the pressure ring near the guide hole, and a set of air guide holes connected to the cavities are provided on the outer wall of the pressure ring.

[0011] Preferably, one end of the threaded sleeve is provided with a set of evenly distributed air guide holes three, and each of the air guide holes three is adapted to the air guide hole two.

[0012] Preferably, the fixed ring, the compression ring, the pressure ring, and the flexible ring are all made of flexible materials. Flexible materials can better fill microscopic uneven surfaces and achieve a tighter contact seal.

[0013] The beneficial effects of this utility model are as follows: The threaded sleeve is threaded to one end of the fixed threaded ring, which compresses the spring at one end of the threaded sleeve. The spring causes the connecting ring to abut against the sliding ring, which in turn compresses the extrusion ring. The extrusion ring then compresses the flexible ring, causing the flexible ring to deform inward and fit against the drive shaft, thus achieving a flexible seal. This effectively avoids dry friction and wear between the drive shaft and the flexible ring, ensuring the safe rotation of the low-pressure cylinder under zero air intake conditions and effectively improving the safety and service life of the device. The locking effect is achieved through the cooperation between the threaded sleeve and the fixed threaded ring, thereby limiting the deformation of the spring, maintaining the pressure of the spring on the connecting ring, and effectively improving the stability of the device. Attached Figure Description

[0014] Figure 1 This is a first-view three-dimensional structural diagram of a pressure-compensating sealing ring for flexible cylinder cutting of a steam turbine low-pressure cylinder, as proposed in this utility model. Figure 2 This is a partial cross-sectional three-dimensional structural diagram of a pressure-compensated sealing ring for flexible cylinder cutting of a steam turbine low-pressure cylinder, as proposed in this utility model. Figure 3 This is a partial exploded three-dimensional structural diagram of a pressure-compensated sealing ring for flexible cylinder cutting of a steam turbine low-pressure cylinder, as proposed in this utility model. Figure 4 This is a partial cross-sectional three-dimensional structural diagram of a pressure compensation component for a flexible cylinder cutting of a low-pressure cylinder in a steam turbine, as proposed in this utility model.

[0015] In the diagram: 1. Drive shaft; 2. Fixed ring; 3. Flexible ring; 4. Extrusion ring; 5. Pressure ring; 6. Cavity 1; 7. Air guide hole 1; 8. Cavity 2; 9. Air guide hole 2; 10. Sliding ring; 11. Connecting ring; 12. Guide rod; 13. Spring; 14. Guide hole; 15. Fixed threaded ring; 16. Threaded sleeve; 17. Air guide hole 3. Detailed Implementation

[0016] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments.

[0017] Example 1, referring to Figure 1-4 A pressure-compensating sealing ring for flexible cylinder cutting of a low-pressure cylinder of a steam turbine includes a drive shaft 1, a fixed ring 2 is provided at one end of the outer peripheral wall of the drive shaft 1, and a compensation component and a fixing component are provided at one end of the fixed ring 2.

[0018] like Figures 2-4 As shown, in one embodiment, the compensation component includes a flexible ring 3 fixedly connected to one end of the fixed ring 2, wherein the flexible ring 3 deforms to fit the transmission shaft 1 to achieve a seal. A compression ring 4 is fixedly connected to the outer peripheral wall of the flexible ring 3, wherein the compression ring 4 deforms to compress the flexible ring 3. A pressure ring 5 is fixedly connected to one end of the compression ring 4. The fixed ring 2, compression ring 4, pressure ring 5, and flexible ring 3 are all made of flexible material. A connecting ring 11 is slidably connected to one end of the pressure ring 5. A set of evenly distributed guide rods 12 is fixedly connected to one end of the connecting ring 11. A spring 13 is sleeved on the outer peripheral wall of each guide rod 12. The pressure ring 5 has a set of evenly distributed guide holes 14 that are adapted to the guide rod 12, which serve to compensate for the pressure. The guide holes 14 act as guide rods 12 and springs 13. The other end of the pressure ring 5 is fixedly connected to a fixed threaded ring 15. One end of the fixed threaded ring 15 is threadedly connected to a threaded sleeve 16. Through the cooperation between the fixed threaded ring 15 and the threaded sleeve 16, the spring 13 maintains its deformation, thereby keeping the connecting ring 11 slightly pressing the sliding ring 10. The outer peripheral wall of the compression ring 4 is slidably connected to the sliding ring 10, which serves to press the compression ring 4. The compression ring 4 has an isosceles trapezoidal cross-section.

[0019] like Figure 2 and Figure 3As shown, in one embodiment, the fixing component includes a set of cavities 6 formed inside the fixing ring 2. One end of the fixing ring 2 has a set of air guide holes 7 connected to the cavities 6. Through the cooperation between the air guide holes 7 and the cavities 6, the pressure difference on both sides of the fixing ring 2 causes the fixing ring 2 to deform and compress the flexible ring 3 to fit against the drive shaft 1. The pressure ring 5 has a set of uniformly distributed cavities 8 near the guide hole 14. The outer wall of the pressure ring 5 has a set of air guide holes 9 connected to the cavities 8. One end of the threaded sleeve 16 has a set of uniformly distributed air guide holes 17, and the air guide holes 17 are all adapted to the air guide holes 9. Through the cooperation between the cavities 8, the air guide holes 9, and the air guide holes 17, the pressure difference on both sides of the pressure ring 5 causes the pressure ring 5 to deform and compress the sliding ring 10.

[0020] Working principle: In use, the sealing ring is fitted onto the outer circumference of the drive shaft 1 near the cylinder-cutting butterfly valve. Then, the threaded sleeve 16 is threaded onto one end of the fixed threaded ring 15, causing the threaded sleeve 16 to compress the spring 13, which in turn causes the spring 13 to drive the connecting ring 11 to abut against the sliding ring 10. This causes the sliding ring 10 to move and compress the compression ring 4, which in turn deforms and compresses the flexible ring 3, causing the flexible ring 3 to deform inward and fit against the drive shaft 1, thus achieving a flexible seal. When the turbine is running normally, the steam pressure on the intermediate-pressure cylinder side is much higher than that on the low-pressure cylinder side. This positive pressure difference causes the pressure ring 5 to deform and compress the sliding ring 10. This causes the sliding ring 10 to further compress the compression ring 4, improving the tightness of the fit between the flexible ring 3 and the drive shaft 1, thereby reducing steam leakage and improving unit efficiency. When the butterfly valve closes to cut off the steam flowing to the low-pressure cylinder, the pressure difference on both sides of the pressure ring 5 decreases rapidly or even reverses. At this time, only the force of the spring 13 acts on the flexible ring 3, and the pressing force of the flexible ring 3 on the drive shaft 1 is greatly reduced, forming a flexible seal. This effectively avoids dry friction and wear between the drive shaft 1 and the flexible ring 3, ensuring the safe rotation of the low-pressure cylinder under zero air intake conditions, and effectively improving the safety and service life of the device.

[0021] The above description is only a preferred embodiment of the present utility model, but the protection scope of the present utility model is not limited thereto. Any equivalent substitutions or changes made by those skilled in the art within the technical scope disclosed in the present utility model, based on the technical solution and the inventive concept of the present utility model, should be included within the protection scope of the present utility model.

Claims

1. A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder, comprising a drive shaft (1), wherein a fixing ring (2) is provided at one end of the outer peripheral wall of the drive shaft (1), characterized in that, It also includes a compensation component and a fixing component disposed at one end of the fixing ring (2); The compensation component includes a flexible ring (3) fixedly connected to one end of a fixed ring (2), a compression ring (4) fixedly connected to the outer peripheral wall of the flexible ring (3), a pressure ring (5) fixedly connected to one end of the compression ring (4), a connecting ring (11) slidably connected to one end of the pressure ring (5), a set of evenly distributed guide rods (12) fixedly connected to one end of the connecting ring (11), a spring (13) sleeved on the outer peripheral wall of each guide rod (12), a set of evenly distributed guide holes (14) adapted to the guide rods (12) being opened inside the pressure ring (5), a fixed threaded ring (15) fixedly connected to the other end of the pressure ring (5), and a threaded sleeve (16) threadedly connected to one end of the fixed threaded ring (15).

2. The pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder according to claim 1, characterized in that, The outer peripheral wall of the extrusion ring (4) is slidably connected to a sliding ring (10), and the cross-section of the extrusion ring (4) is set in an isosceles trapezoidal structure.

3. A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder according to claim 2, characterized in that, The fixing component includes a set of cavities (6) opened inside the fixing ring (2), and one end of the fixing ring (2) is provided with a set of air guide holes (7) connected to the cavity (6).

4. A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder according to claim 3, characterized in that, The pressure ring (5) has a set of uniformly distributed cavities (8) inside near the guide hole (14), and the outer wall of the pressure ring (5) has a set of air guide holes (9) connected to the cavities (8).

5. A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder according to claim 4, characterized in that, One end of the threaded sleeve (16) is provided with a set of evenly distributed air guide holes three (17), and the air guide holes three (17) are all adapted to the air guide holes two (9).

6. A pressure-compensating sealing ring for flexible cylinder cutting in a steam turbine low-pressure cylinder according to claim 5, characterized in that, The fixed ring (2), the extrusion ring (4), the pressure ring (5), and the flexible ring (3) are all made of flexible materials.

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