Low-pressure inner cylinder for steam turbine of thermal power plant
By setting up multiple steam cavity chambers and pumping holes in the low -voltage internal cylinder of the fire power plant, the uniform diffusion and temperature distribution of the steam can be achieved, solving the problem of low -voltage internal cylinder deformation and poor thermal expansion, improvement of operating efficiency and stability sex.
Patent Information
- Application Number
- CN202420446324.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-08
- Publication Date
- 2025-01-28
- Estimated Expiration
- 2034-03-08
AI Technical Summary
After long-term operation of the domestic 300MW and 600MW thermal power plant steam turbines, the low-pressure inner cylinders have different degrees of deformation, resulting in problems such as excessive temperature gradient, uneven temperature, and poor thermal expansion.
Design a low -voltage inner cylinder for the steam turbine of thermal power plant. By setting up the first steam cavity room, the second steam cavity chamber and the third steam cavity chamber of the left and right sides of the vapor chamber, the steam will be spread evenly, and the axis shaft is balanced The thrust is distributed evenly through the pumping holes and steam pipes.
Improve the balance and stability of the low -pressure cylinder body, avoid deformation, ensure the smoothness of thermal expansion, and improve the operating efficiency.
Smart Images
Figure CN222414966U_ABST
Abstract
Description
Technical Field
[0001] The present application relates to steam turbine technology, and in particular to a low-pressure inner cylinder for a steam turbine in a thermal power plant. 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 and becomes an accelerated airflow, which is then sprayed onto the blades, causing the rotor with the blades 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 devices.
[0003] The steam turbine is mainly composed of a high-pressure cylinder, a medium-pressure cylinder and a low-pressure cylinder. When the steam turbine converts the thermal energy of high-temperature steam into high-speed rotating mechanical energy and drives the generator to cut the magnetic lines of force and convert them into electrical energy, the steam has to do work, its pressure decreases, and its volume expands. Therefore, the steam expands from high pressure to medium pressure / low pressure. The low-pressure cylinder includes a low-pressure outer cylinder and a low-pressure inner cylinder. The low-pressure inner cylinder is relatively large in size. Due to the level of design and manufacturing, many domestic 300MW and 600MW units have different degrees of deformation in the low-pressure inner cylinder after long-term operation, resulting in excessive temperature gradients in each chamber of the low-pressure inner cylinder, uneven temperature, and poor thermal expansion. Utility Model Content
[0004] The present application provides a low-pressure inner cylinder for a steam turbine in a thermal power plant, which is used to solve the technical problems described in the above-mentioned background technology.
[0005] In order to solve the above technical problems, this application adopts the following technical solutions:
[0006] The present application provides a low-pressure inner cylinder for a steam turbine in a thermal power plant, comprising:
[0007] A low-pressure cylinder body, wherein a steam inlet chamber is arranged in the middle of the low-pressure cylinder body, a steam inlet passage is connected to the steam inlet chamber, and a first steam extraction chamber, a second steam extraction chamber and a third steam extraction chamber are arranged on the left and right sides of the steam inlet chamber respectively away from the steam inlet chamber;
[0008] Each of the first steam extraction chambers, each of the second steam extraction chambers and each of the third steam extraction chambers is provided with a steam extraction hole communicating with the steam inlet chamber;
[0009] Each of the first steam extraction chambers, each of the second steam extraction chambers and each of the third steam extraction chambers is connected to a steam extraction pipe connected to the low-pressure cylinder body.
[0010] Optionally, the steam inlet chamber, each of the first steam extraction chambers, each of the second steam extraction chambers and each of the third steam extraction chambers are arranged along the circumference of the low-pressure cylinder body;
[0011] Each of the first steam extraction chambers, each of the second steam extraction chambers, and each of the third steam extraction chambers is provided with a plurality of the steam extraction holes at even intervals along the circumference thereof.
[0012] Optionally, the diameter of the steam inlet flow passage decreases gradually as it approaches the low-pressure cylinder body.
[0013] Optionally, the steam inlet chamber is surrounded by two annular first baffles and the inner wall of the low-pressure cylinder body, and the two first baffles are close to each other and are both inclinedly arranged on the inner wall of the low-pressure cylinder body.
[0014] Optionally, a plurality of reinforcing ribs are arranged at equal intervals in the steam inlet chamber, and two ends of each of the reinforcing ribs are respectively arranged on side walls of two first partitions close to each other.
[0015] Optionally, each of the first steam extraction chambers is surrounded by an annular second baffle, a third baffle, the first baffle, and the inner wall of the low-pressure cylinder, and the second steam extraction chamber and the third steam extraction chamber are both surrounded by two second baffles, the third baffle, and the inner wall of the low-pressure cylinder;
[0016] The second partition is arranged on the inner wall of the low-pressure cylinder body and is parallel to the first partition located on the same side of the steam inlet chamber as the first partition, and the steam extraction hole is arranged on the third partition.
[0017] Optionally, a lifting lug is provided on the side of the low-pressure cylinder body.
[0018] The low-pressure inner cylinder for the steam turbine of a thermal power plant provided by the present application, by respectively arranging the first steam extraction chamber, the second steam extraction chamber and the third steam extraction chamber on the left and right sides of the steam inlet chamber, makes the steam entering the steam inlet chamber of the low-pressure cylinder body diffuse evenly to the left and right sides of the steam inlet chamber, so as to balance the axial thrust in the low-pressure cylinder body, so that the low-pressure cylinder body has better balance and is more stable during the entire operation process, and is not easy to deform, thereby ensuring the smooth thermal expansion. In addition, the steam entering the steam inlet chamber through the steam inlet flow channel enters the first steam extraction chamber, the second steam extraction chamber and the third steam extraction chamber in sequence through the steam extraction hole, so that the steam flow rate in the low-pressure cylinder body is more uniform and the temperature distribution is more uniform, and the steam entering the above-mentioned chambers is discharged to the outside of the low-pressure cylinder body through the steam extraction pipes connected thereto, avoiding the situation where the temperature in the low-pressure cylinder body is too high, thereby improving the operation efficiency of the low-pressure inner cylinder. BRIEF DESCRIPTION OF THE DRAWINGS
[0019] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.
[0020] Figure 1 A schematic diagram of the structure of a low-pressure inner cylinder for a steam turbine in a thermal power plant provided in one embodiment of the present application;
[0021] Figure 2 A schematic structural diagram of a low-pressure inner cylinder for a steam turbine in a thermal power plant provided by another embodiment of the present application;
[0022] Figure 3 A schematic structural diagram of a low-pressure inner cylinder for a steam turbine in a thermal power plant provided in another embodiment of the present application.
[0023] In the figure: 100, low-pressure cylinder body; 101, steam inlet chamber; 1011, steam inlet flow channel; 1012, first baffle; 1013, reinforcing rib; 1014, second baffle; 1015, third baffle; 102, first steam extraction chamber; 103, second steam extraction chamber; 104, third steam extraction chamber; 105, lifting ear; 200, steam extraction hole; 300, steam extraction pipe. DETAILED DESCRIPTION
[0024] In order to make the purpose, technical scheme and advantages of the embodiments of the present application clearer, the technical scheme in the embodiments of the present application is clearly and completely described below. Obviously, the described embodiments are part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work also fall within the scope of protection of the present application.
[0025] refer to Figures 1 to 3 The present application provides a low-pressure inner cylinder for a steam turbine in a thermal power plant, comprising:
[0026] The low-pressure cylinder 100 has a steam inlet chamber 101 in the middle thereof, and the steam inlet chamber 101 is connected to a steam inlet channel 1011. The left and right sides of the steam inlet chamber 101 are provided with a first steam extraction chamber 102, a second steam extraction chamber 103 and a third steam extraction chamber 104, respectively, away from the steam inlet chamber 101. 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, so that the rotor with the blade row rotates and performs work externally. When the steam turbine converts the thermal energy of the high-temperature steam into high-speed rotating mechanical energy and drives the generator to cut When the magnetic lines of force are converted into electrical energy, the steam has to do work, its pressure decreases, and its volume expands. Specifically, the steam expands from the high-pressure cylinder to the medium-pressure cylinder and the low-pressure cylinder in sequence, and the steam in the medium-pressure cylinder enters the low-pressure cylinder body 100 through the steam inlet channel 1011. Since the first steam extraction chamber 102, the second steam extraction chamber 103 and the third steam extraction chamber 104 are respectively provided on the left and right sides of the steam inlet chamber 101, the steam entering the steam inlet chamber 101 through the steam inlet channel 1011 can be evenly distributed in the low-pressure cylinder body 100, balancing the axial thrust in the low-pressure cylinder body 100 and making the temperature in the low-pressure cylinder body 100 more uniform, avoiding excessive local temperature.
[0027] Each first steam extraction chamber 102, each second steam extraction chamber 103 and each third steam extraction chamber 104 is provided with a steam extraction hole 200 connected to the steam inlet chamber 101; wherein, the steam in the steam inlet chamber 101 entering the low-pressure cylinder body 100 from the steam inlet channel 1011 enters the first steam extraction chamber 102 through the steam extraction hole 200 on the first steam extraction chamber 102, enters the second steam extraction chamber 103 through the steam extraction hole 200 on the second steam extraction chamber 103, and enters the third steam extraction chamber 104 through the steam extraction hole 200 on the third steam extraction chamber 104.
[0028] Each first steam extraction chamber 102, each second steam extraction chamber 103 and each third steam extraction chamber 104 are connected to a steam extraction pipe 300 connected to the outside of the low-pressure cylinder 100. Among them, one end of each steam extraction pipe 300 away from the low-pressure cylinder 100 is used to connect to the low-pressure heater, and the function of the low-pressure heater is to use the steam that has done part of the work in the steam turbine to extract it into the heater to heat the feed water, increase the temperature of the water, reduce the amount of steam discharged from the steam turbine to the condenser, reduce energy loss, and improve the cycle efficiency of the thermal system. That is, the steam entering the first steam extraction chamber 102, the second steam extraction chamber 103 and the third steam extraction chamber 104 through the steam extraction hole 200 is respectively discharged to the low-pressure heater through the steam extraction pipe 300 connected thereto, so that the heat contained in the steam entering the low-pressure cylinder 100 is fully utilized.
[0029] The low-pressure inner cylinder for a steam turbine in a thermal power plant provided in the present application is configured such that a first steam extraction chamber 102, a second steam extraction chamber 103 and a third steam extraction chamber 104 are respectively arranged on the left and right sides of the steam inlet chamber 101, so that the steam entering the steam inlet chamber 101 of the low-pressure cylinder body 100 is evenly diffused to the left and right sides of the steam inlet chamber 101, thereby balancing the axial thrust in the low-pressure cylinder body 100, making the low-pressure cylinder body 100 better balanced and more stable during the entire operation process, and not easy to deform, thereby ensuring smooth thermal expansion. In addition, the steam entering the steam inlet chamber 101 through the steam inlet flow channel 1011 enters the first steam extraction chamber 102, the second steam extraction chamber 103 and the third steam extraction chamber 104 in sequence through the steam extraction hole 200, so that the steam flow rate in the low-pressure cylinder 100 is more uniform and the temperature distribution is more uniform, and the steam entering the above-mentioned chambers is discharged to the outside of the low-pressure cylinder 100 through the steam extraction pipe 300 connected thereto, avoiding the situation where the temperature in the low-pressure cylinder 100 is too high, thereby improving the operating efficiency of the low-pressure cylinder 100.
[0030] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 In the present application, the steam inlet chamber 101, each first steam extraction chamber 102, each second steam extraction chamber 103 and each third steam extraction chamber 104 are all arranged along the circumference of the low-pressure cylinder 100; in addition, each first steam extraction chamber 102, each second steam extraction chamber 103 and each third steam extraction chamber 104 are evenly spaced along the circumference thereof with a plurality of steam extraction holes 200. The arrangement of each first steam extraction chamber 102, each second steam extraction chamber 103 and each third steam extraction chamber 104 and the arrangement of the plurality of steam extraction holes 200 thereon enable the steam in the steam inlet chamber 101 to uniformly enter the above-mentioned chambers, so that the temperature in the above-mentioned chambers is relatively uniform and the temperature gradient is relatively small, thereby ensuring the stability of thermal expansion of the low-pressure cylinder 100.
[0031] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 , the diameter of the steam inlet flow channel 1011 in the present application decreases gradually as it approaches the low-pressure cylinder 100. Among them, the end of the steam inlet flow channel 1011 away from the low-pressure cylinder 100 is connected to the intermediate-pressure cylinder of the steam turbine through a connecting pipe, and the steam expanded in the intermediate-pressure cylinder enters the steam inlet chamber 101 of the low-pressure cylinder 100 through the connecting pipe and the steam inlet flow channel 1011 in sequence, and the pipe diameter of the steam inlet flow channel 1011 gradually decreases between the connecting pipe and the low-pressure cylinder 100, so that the flow rate of the steam entering the steam inlet chamber 101 gradually increases, thereby improving the diffusion rate of the steam in the low-pressure cylinder 100, and further improving the operating efficiency of the low-pressure cylinder 100.
[0032] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 The steam inlet chamber 101 in the present application is formed by two annular first baffles 1012 and the inner wall of the low-pressure cylinder 100. The two first baffles 1012 are close to each other and are both inclined on the inner wall of the low-pressure cylinder 100. Among them, the projection growth of the inclined first baffle 1012 in the axial direction of the low-pressure cylinder 100 can make the axial temperature gradient distribution in the low-pressure cylinder 100 more uniform, thereby ensuring the smoothness of the thermal expansion of the low-pressure cylinder 100. The distance between the two first baffles 1012 determines the volume of the steam inlet chamber 101, and the spacing between the two first baffles 1012 can be set according to the actual size of the low-pressure cylinder 100 and the requirements during operation. Therefore, the present application does not make specific limitations on it.
[0033] In some embodiments, reference Figure 2 In the present application, a plurality of reinforcing ribs 1013 are arranged at equal intervals in the steam inlet chamber 101, and the two ends of each reinforcing rib 1013 are respectively arranged on the side walls of the two first partitions 1012 that are close to each other. The arrangement of the plurality of reinforcing ribs 1013 improves the stability between the two first partitions 1012, and the plurality of reinforcing ribs 1013 can disperse the steam entering the steam inlet chamber 101, so that the steam is evenly diffused in the steam inlet chamber 101, thereby making the temperature distribution in the steam inlet chamber 101 uniform.
[0034] In some embodiments, reference Figure 1 , Figure 2 and Figure 3 In the present application, each first steam extraction chamber 102 is surrounded by an annular second partition 1014, a third partition 1015, a first partition 1012 and the inner wall of the low-pressure cylinder 100, and the second steam extraction chamber 103 and the third steam extraction chamber 104 are both surrounded by two second partitions 1014, a third partition 1015 and the inner wall of the low-pressure cylinder 100; specifically, the second partition 1014 is arranged on the inner wall of the low-pressure cylinder 100 and is parallel to the first partition 1012 located on the same side of the steam inlet chamber 101, the third partition 1015 is cylindrical and connected to the first partition 1012 and the second partition 1014 on a side away from the low-pressure cylinder, the outer wall of the barrel of the third partition 1015 is at a preset distance from the inner wall of the low-pressure cylinder, and the steam extraction hole 200 is arranged on the third partition 1015.
[0035] In the above embodiment, the second steam extraction chamber 103 and the third steam extraction chamber 104 are both closed chambers, and the second steam extraction chamber 103 and the third steam extraction chamber 104 are connected with the low-pressure cylinder 100 through the steam extraction holes 200 provided thereon, so that the steam entering the low-pressure cylinder 100 enters the second steam extraction chamber 103 and the third steam extraction chamber 104 through the steam extraction holes 200, so that the steam entering the low-pressure cylinder 100 is sufficient for the low-pressure cylinder 100 to operate and do work. The steam after exhaust still has residual heat and enters the second extraction chamber 103 through the extraction hole 200 on the second extraction chamber 103, and enters the third extraction chamber 104 through the extraction hole 200 on the third extraction chamber 104, and the steam in the second extraction chamber 103 and the steam in the third extraction chamber 104 are discharged to the outside of the low-pressure cylinder 100 through the extraction pipe 300 thereon for use in heating for other purposes, thereby improving the utilization efficiency of steam.
[0036] In some embodiments, reference Figure 3 The side of the low-pressure cylinder 100 in the present application is provided with a lifting lug 105. The lifting lug 105 can make the low-pressure cylinder 100 more convenient to move. In addition, there can be multiple lifting lugs 105, which can be set according to actual needs. Therefore, the present application does not further limit it.
[0037] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit it. Although the present application has been described in detail with reference to the aforementioned embodiments, ordinary technicians in the field should understand that they can still modify the technical solutions recorded in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.
Claims
1. A low-pressure inner cylinder for a steam turbine in a thermal power plant, characterized in that: include: A low-pressure cylinder (100), wherein a steam inlet chamber (101) is disposed in the middle of the low-pressure cylinder (100), a steam inlet passage (1011) is connected to the steam inlet chamber (101), and a first steam extraction chamber (102), a second steam extraction chamber (103) and a third steam extraction chamber (104) are disposed on the left and right sides of the steam inlet chamber (101) in order away from the steam inlet chamber (101); Each of the first steam extraction chambers (102), each of the second steam extraction chambers (103), and each of the third steam extraction chambers (104) is provided with a steam extraction hole (200) that is in communication with the steam inlet chamber (101); Each of the first steam extraction chambers (102), each of the second steam extraction chambers (103), and each of the third steam extraction chambers (104) is connected to a steam extraction pipe (300) connected to the outside of the low-pressure cylinder body (100).
2. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to claim 1, characterized in that: The steam inlet chamber (101), each of the first steam extraction chambers (102), each of the second steam extraction chambers (103), and each of the third steam extraction chambers (104) are all arranged along the circumference of the low-pressure cylinder (100); Each of the first steam extraction chambers (102), each of the second steam extraction chambers (103), and each of the third steam extraction chambers (104) is provided with a plurality of steam extraction holes (200) at even intervals along the circumference thereof.
3. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to claim 1, characterized in that: The diameter of the steam inlet channel (1011) decreases gradually as it approaches the low-pressure cylinder (100).
4. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to claim 1, characterized in that: The steam inlet chamber (101) is surrounded by two annular first baffles (1012) and the inner wall of the low-pressure cylinder (100); the two first baffles (1012) are close to each other and are both inclinedly arranged on the inner wall of the low-pressure cylinder (100).
5. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to claim 4, characterized in that: A plurality of reinforcing ribs (1013) are arranged at equal intervals in the steam inlet chamber (101), and two ends of each of the reinforcing ribs (1013) are respectively arranged on the side walls of the two first partitions (1012) that are close to each other.
6. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to claim 4, characterized in that: Each of the first steam extraction chambers (102) is surrounded by an annular second baffle (1014), a third baffle (1015), the first baffle (1012) and the inner wall of the low-pressure cylinder (100); and each of the second steam extraction chambers (103) and the third steam extraction chambers (104) is surrounded by two of the second baffles (1014), the third baffle (1015) and the inner wall of the low-pressure cylinder (100); The second partition plate (1014) is arranged on the inner wall of the low-pressure cylinder body (100) and is parallel to the first partition plate (1012) located on the same side of the steam inlet chamber (101) as the first partition plate (1012), and the steam extraction hole (200) is arranged on the third partition plate (1015).
7. The low-pressure inner cylinder for a steam turbine in a thermal power plant according to any one of claims 1 to 6, characterized in that: A lifting lug (105) is provided on the side of the low-pressure cylinder (100).