Medium-low pressure communicating pipe for steam turbine
By designing a medium and low pressure communication pipe with a multi-layer insulation structure in the steam turbine, the pressure loss problem caused by the temperature drop in the low temperature environment is solved, the working efficiency of the steam turbine is improved, and the normal operation of the pipeline is ensured in the low temperature environment.
Patent Information
- Application Number
- CN202411879340.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-19
- Publication Date
- 2025-03-18
AI Technical Summary
During the operation of the steam turbine, especially in a low-temperature environment, the steam temperature flowing through the medium and low-pressure communication pipe drops seriously, resulting in a large pressure loss when the steam enters the low-pressure cylinder, reducing the working efficiency of the steam turbine.
A medium and low pressure communication pipe for steam turbines is designed, and a multi-layer insulation structure is adopted, including an insulation inner layer, an insulation outer layer, a fixed layer, a smear layer and an outer surface layer. Through these layers of structures, the heat loss of medium is reduced, the temperature and pressure of steam is maintained, and the pipeline is prevented from freezing in a low-temperature environment.
By reducing the heat dissipation loss of steam, the pressure loss of steam when entering the low-pressure cylinder is reduced, the working efficiency of the turbine is improved, and the normal operation of the pipeline is ensured in a low-temperature environment to prevent freezing and corrosion.
Smart Images
Figure CN119641455A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the technical field of steam turbines, and in particular to a medium- and low-pressure connecting pipe for a steam turbine. Background Art
[0002] A steam turbine, also known as a steam turbine engine, is a rotary steam power device. High-temperature and high-pressure steam passes through a fixed nozzle to become an accelerated airflow and then is sprayed onto the blades, causing the rotor equipped with blade rows to rotate and perform work externally. Steam turbines are the main equipment in modern thermal power plants and are also used in the metallurgical industry, chemical industry, and ship power plants. In steam turbines, the medium- and low-pressure connecting pipes play an important role. The steam discharged from the medium-pressure cylinder flows into the low-pressure cylinder through the medium- and low-pressure connecting pipes. The connecting pipe is equipped with multiple guide vane rings, which can change the direction of the airflow smoothly, thereby introducing steam into the low-pressure cylinder with minimal pressure loss.
[0003] During the operation of the steam turbine, especially in a low-temperature environment, the temperature of the steam flowing through the medium- and low-pressure connecting pipes drops seriously, resulting in a large pressure loss when the steam enters the low-pressure cylinder, causing the working efficiency of the steam turbine to decrease. Summary of the invention
[0004] In order to reduce the pressure loss of steam, the present application provides a medium- and low-pressure connecting pipe for a steam turbine.
[0005] The medium and low pressure connecting pipe for a steam turbine provided in the present application adopts the following technical solution:
[0006] A medium-low pressure connecting pipe for a steam turbine, comprising: a connecting pipe body, an air inlet and an air outlet are respectively arranged at both ends of the connecting pipe body, the air inlet is communicated with the air outlet, the air inlet is communicated with the exhaust end of the medium-pressure cylinder, the air outlet is communicated with the air inlet end of the low-pressure cylinder, the air inlet and the air outlet are both provided with connecting flanges, and the connecting flanges are used to connect the medium-pressure cylinder and the low-pressure cylinder;
[0007] The outer side wall of the connecting pipe body is covered with a heat preservation structure, and the heat preservation structure is used to maintain the temperature and pressure of the medium in the connecting pipe body.
[0008] In a possible implementation, the insulation structure includes an insulation inner layer, an insulation outer layer, a fixing layer, a finishing layer and an outer layer, the insulation inner layer is attached to the outer wall of the connecting pipe body, the insulation inner layer includes a plurality of inner insulation blocks, the plurality of inner insulation blocks are evenly distributed circumferentially along the outer wall of the connecting pipe body, the inner insulation blocks are arranged in a trapezoidal shape, the bottoms of two adjacent inner insulation blocks abut against each other, and an inner filling seam is arranged between two adjacent inner insulation blocks, and the inner filling seam is filled with a base material.
[0009] In a possible implementation, the thermal insulation outer layer is attached to the outer side wall of the thermal insulation inner layer, the thermal insulation outer layer includes a plurality of outer thermal insulation blocks, the plurality of outer thermal insulation blocks are evenly distributed along the outer side wall of the thermal insulation inner layer, the outer thermal insulation blocks are arranged in a trapezoidal shape, the bottoms of two adjacent outer thermal insulation blocks abut against each other, and an outer filling seam is arranged between two adjacent outer thermal insulation blocks, and the outer filling seam is filled with a base material;
[0010] The inner layer heat-insulating blocks and the outer layer heat-insulating blocks are circumferentially staggered with respect to the side wall of the connecting pipe body.
[0011] In a possible implementation, the fixed layer includes a plurality of tightening wires and a metal mesh, the tightening wires are sleeved on the outer wall of the thermal insulation outer layer, and the plurality of tightening wires are evenly distributed along the axial direction of the connecting pipe body, the metal mesh is arranged on the outside of the tightening wires, and the metal mesh covers the thermal insulation outer layer.
[0012] In a possible implementation, the plastering layer is disposed on the outer side of the fixed layer, and the plastering layer includes a plastering material, and the plastering material is evenly coated on the outer side wall of the metal wire mesh.
[0013] In a possible implementation, the outer surface layer includes glass fiber cloth, and the glass fiber cloth is attached to the outer side wall of the plaster layer.
[0014] Through the medium- and low-pressure connecting pipe for a steam turbine provided by the present application, steam enters the air inlet from the medium-pressure cylinder and is discharged from the exhaust port to the low-pressure cylinder. The insulation structure is set, and the insulation inner layer and the insulation outer layer jointly insulate the connecting pipe body, which is convenient for reducing the heat dissipation loss of the medium and ensuring that the medium in the pipeline can maintain the required temperature and pressure; at the same time, under low ambient temperature conditions, the insulation layer can also prevent the pipeline from freezing and ensure the normal operation of the pipeline. The fixing layer fixes the insulation layer and the insulation outer layer to the outer wall of the connecting pipe body through iron wire and metal wire mesh, which is convenient for preventing the insulation layer from falling off, and at the same time, it can also increase the strength of the pipeline; the insulation layer can prevent condensation from forming on the surface of the pipeline and avoid corrosion of the pipeline and equipment surface. In addition, the outer layer uses glass fiber cloth to adhere to the outer wall of the finishing layer, which is convenient for improving the corrosion resistance of the connecting pipe body. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] The accompanying drawings are used to provide a further understanding of the present application and constitute a part of the specification. Together with the embodiments of the present application, they are used to explain the present application and do not constitute a limitation to the present application.
[0016] Figure 1 It is a schematic diagram of the overall structure of a medium- and low-pressure connecting pipe for a steam turbine of the present application.
[0017] Figure 2It is a schematic diagram of the insulation structure.
[0018] Description of the drawings: 1. Connecting pipe body; 11. Air inlet; 12. Air outlet; 13. Connecting flange; 2. Insulation structure; 21. Inner insulation layer; 211. Inner insulation block; 212. Inner filling seam; 213. Base material; 22. Outer insulation layer; 221. Outer insulation block; 222. Outer filling seam; 23. Fixed layer; 231. Tightening wire; 232. Metal mesh; 24. Surface layer; 24. Surface material; 25. Outer surface layer; 251. Fiberglass cloth. DETAILED DESCRIPTION
[0019] In order to make the purpose, technical solutions and advantages of this application clearer, the technical solutions in this application will be clearly and completely described below in conjunction with the drawings in this application. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0020] The terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features; in the description of this application, unless otherwise specified, "plurality" means two or more.
[0021] The following is combined with Figure 1-2 This application is described in further detail.
[0022] The embodiment of the present application discloses a medium- and low-pressure connecting pipe for a steam turbine.
[0023] Reference Figure 1 A medium- and low-pressure connecting pipe for a steam turbine comprises: a connecting pipe body 1, an air inlet 11 and an air outlet 12 are respectively arranged at both ends of the connecting pipe body 1, the air inlet 11 is connected to the air outlet 12, the air inlet 11 is connected to the exhaust end of the medium-pressure cylinder, and the air outlet 12 is connected to the air inlet end of the low-pressure cylinder, and the air inlet 11 and the air outlet 12 are both provided with a connecting flange 13, and the connecting flange 13 is used to connect the medium-pressure cylinder and the low-pressure cylinder; the outer wall of the connecting pipe body 1 is covered with a thermal insulation structure 2, and the thermal insulation structure 2 is used to maintain the temperature and pressure of the medium in the connecting pipe body 1.
[0024] Reference Figure 2The insulation structure 2 includes an insulation inner layer 21, an insulation outer layer 22, a fixing layer 23, a finishing layer 24 and an outer layer 25. The insulation inner layer 21 is attached to the outer wall of the connecting pipe body 1. The insulation inner layer 21 includes a plurality of inner insulation blocks 211. The plurality of inner insulation blocks 211 are evenly distributed along the circumference of the outer wall of the connecting pipe body 1. The inner insulation blocks 211 are arranged in a trapezoidal shape. The bottoms of two adjacent inner insulation blocks 211 abut against each other, and an inner filling seam 212 is arranged between two adjacent inner insulation blocks 211. The inner filling seam 212 is filled with a primer material 213. The primer material 213 can be plaster, bonding gypsum, or thermal insulation mortar, as long as it can achieve firm bonding to the inner insulation blocks 211. The insulating outer layer 22 is attached to the outer wall of the insulating inner layer 21, and the insulating outer layer 22 includes multiple outer insulation blocks 221, and the multiple outer insulation blocks 221 are evenly distributed along the outer wall of the insulating inner layer 21. The outer insulation blocks 221 are arranged in a trapezoidal shape, and the bottoms of two adjacent outer insulation blocks 221 abut against each other, and an outer filling seam 222 is arranged between two adjacent outer insulation blocks 221, and the outer filling seam 222 is filled with a base material 213; the inner insulation blocks 211 and the outer insulation blocks 221 are circumferentially staggered about the side wall of the connecting pipe body 1. The fixed layer 23 includes a plurality of tightening wires 231 and a metal mesh 232. The tightening wires 231 are sleeved on the outer side wall of the heat-insulating outer layer 22, and the plurality of tightening wires 231 are evenly distributed along the axial direction of the connecting pipe body 1. The metal mesh 232 is arranged outside the tightening wires 231, and the metal mesh 232 covers the heat-insulating outer layer 22. The plastering layer 24 is arranged outside the fixed layer 23, and the plastering layer 24 includes a plastering material 24, and the plastering material 24 is evenly coated on the outer side wall of the metal mesh 232. The outer layer 25 includes a glass fiber cloth 251, and the glass fiber cloth 251 is attached to the outer side wall of the plastering layer 24.
[0025] The implementation principle of the medium-low pressure connecting pipe for a steam turbine of the present application is as follows: steam enters the air inlet 11 from the medium pressure cylinder and is discharged from the exhaust port to the low pressure cylinder. The inner insulation layer 21 and the outer insulation layer 22 jointly insulate the connecting pipe body 1, which is convenient for reducing the heat dissipation loss of the medium and ensuring that the medium in the pipeline can maintain the required temperature and pressure; at the same time, under low ambient temperature conditions, the insulation layer can also prevent the pipeline from freezing and ensure the normal operation of the pipeline. The fixing layer 23 fixes the insulation layer and the outer insulation layer 22 to the outer wall of the connecting pipe body 1 through iron wire and metal wire mesh 232, which is convenient for preventing the insulation layer from falling off and at the same time, it can also increase the strength of the pipeline; the insulation layer can prevent condensation from forming on the surface of the pipeline and avoid corrosion of the pipeline and equipment surface. In addition, the outer layer 25 uses glass fiber cloth 251 to adhere to the outer wall of the finishing layer 24, which is convenient for improving the corrosion resistance of the connecting pipe body 1.
[0026] The above embodiments are only used to illustrate the technical solution of the present application, but not to limit it. The present application is not limited to the exact structure described above and illustrated in the accompanying drawings, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For ordinary technicians in the technical field to which the present application belongs, various changes and modifications made without departing from the concept of the present application should be deemed to belong to the protection scope of the present application.
Claims
1. A medium and low pressure connecting pipe for a steam turbine, characterized in that: include: A connecting pipe body (1), wherein an air inlet (11) and an air outlet (12) are respectively arranged at two ends of the connecting pipe body (1), the air inlet (11) and the air outlet (12) are connected, the air inlet (11) is connected to the exhaust end of the medium-pressure cylinder, and the air outlet (12) is connected to the air inlet end of the low-pressure cylinder, and the air inlet (11) and the air outlet (12) are both provided with connecting flanges (13), and the connecting flanges (13) are used to connect the medium-pressure cylinder and the low-pressure cylinder; The outer wall of the connecting pipe body (1) is coated with a heat-insulating structure (2), and the heat-insulating structure (2) is used to maintain the temperature and pressure of the medium in the connecting pipe body (1).
2. A medium and low pressure connecting pipe for a steam turbine according to claim 1, characterized in that: The thermal insulation structure (2) comprises a thermal insulation inner layer (21), a thermal insulation outer layer (22), a fixing layer (23), a finishing layer (24) and an outer layer (25); the thermal insulation inner layer (21) is attached to the outer side wall of the connecting pipe body (1); the thermal insulation inner layer (21) comprises a plurality of inner layer thermal insulation blocks (211); the plurality of inner layer thermal insulation blocks (211) are evenly distributed along the circumference of the outer side wall of the connecting pipe body (1); the inner layer thermal insulation blocks (211) are arranged in a trapezoidal shape; the bottoms of two adjacent inner layer thermal insulation blocks (211) abut against each other; an inner layer filling seam (212) is arranged between two adjacent inner layer thermal insulation blocks (211); the inner layer filling seam (212) is filled with a base material (213).
3. A medium and low pressure connecting pipe for a steam turbine according to claim 2, characterized in that: The thermal insulation outer layer (22) is attached to the outer side wall of the thermal insulation inner layer (21), the thermal insulation outer layer comprises a plurality of outer layer thermal insulation blocks (221), the plurality of outer layer thermal insulation blocks (221) are evenly distributed along the outer side wall of the thermal insulation inner layer (21), the outer layer thermal insulation blocks (221) are arranged in a trapezoidal shape, the bottoms of two adjacent outer layer thermal insulation blocks (221) abut against each other, and an outer layer filling seam (222) is arranged between two adjacent outer layer thermal insulation blocks (221), and the outer layer filling seam (222) is filled with a base material (213); The inner layer heat-insulating block (211) and the outer layer heat-insulating block (221) are arranged alternately in the circumferential direction with respect to the side wall of the connecting pipe body (1).
4. A medium and low pressure connecting pipe for a steam turbine according to claim 3, characterized in that: The fixed layer (23) comprises a plurality of tightening wires (231) and a metal mesh (232); the tightening wires (231) are sleeved on the outer wall of the thermal insulation outer layer, and the plurality of tightening wires (231) are evenly distributed along the axial direction of the connecting pipe body (1); the metal mesh (232) is arranged on the outer side of the tightening wires (231), and the metal mesh (232) covers the thermal insulation outer layer (22).
5. A medium and low pressure connecting pipe for a steam turbine according to claim 4, characterized in that: The plastering layer (24) is arranged on the outside of the fixing layer (23), and the plastering layer (24) comprises a plastering material (24), and the plastering material (24) is evenly coated on the outer side wall of the metal wire mesh (232).
6. A medium and low pressure connecting pipe for a steam turbine according to claim 5, characterized in that: The outer surface layer (25) comprises a glass fiber cloth (251), and the glass fiber cloth (251) is attached to the outer side wall of the plastering layer (24).