Efficient steam turbine unit nozzle device

Abstract

The invention relates to the technical field of steam turbines, in particular to an efficient steam turbine set nozzle device which comprises a nozzle body, the nozzle body comprises a first nozzle set, a second nozzle set, a third nozzle set and a fourth nozzle set, and the first nozzle set, the second nozzle set, the third nozzle set and the fourth nozzle set each comprise a peripheral band. A blade grid first block and a blade grid tail block are fixedly installed on one side of the outer shroud band, a plurality of sets of regulating stage stationary blades are distributed between the blade grid first block and the blade grid tail block, and an inner shroud band is fixedly installed on the other side of the blade grid first block and the other side of the blade grid tail block. High-temperature and high-pressure steam passes through the inside of the nozzle body, the high-temperature and high-pressure steam acts on the connecting shell to deform due to gaps among the multiple nozzle sets, meanwhile, thermal expansion gaps change to extrude the connecting shell, bidirectional acting force is generated, then the gaps between the adjacent nozzle sets are reduced, and air leakage is avoided when airflow passes through blades and a channel. The regulating-stage stationary blades with a certain curve radian are adopted, so that the steam resistance is fully reduced, and the steam efficiently passes through.

Description

Technical Field

[0001] The invention relates to the technical field of steam turbines, and in particular to a high-efficiency steam turbine unit nozzle device. Background Art

[0002] The nozzle is one of the main components of a steam turbine. Its function is to convert the thermal energy of steam into the kinetic energy of high-speed steam flow, so that the high-speed steam flow is ejected from the nozzle in a certain direction, enters the moving blade grid, and drives the impeller to rotate and do work.

[0003] In the prior art, for example, the patent with publication number CN101215977A discloses a turbine nozzle group and its processing technology, which includes an outer ring support body, an inner ring support body and a blade grid therebetween, wherein the blade grid is annular and has a plurality of circumferentially arranged guide vanes, wherein the guide vanes are separate structures from the inner ring and the outer ring, and all the guide vanes are assembled to form a blade grid, which is assembled on the inner and outer ring support bodies to form a nozzle group, and a sealing key is provided at the joint between the upper and lower halves of the nozzle group and the nozzle chamber.

[0004] When the turbine nozzle group of the above structure is heated, the arc segment of the nozzle group can expand freely in the circumferential direction. However, when the nozzle group expands, the thermal expansion gap cannot be controlled, and air leakage occurs when the airflow passes through the blades and channels, resulting in low steam passage efficiency and inability to fully utilize the steam kinetic energy. Summary of the invention

[0005] In view of this, the purpose of the present invention is to propose a high-efficiency steam turbine unit nozzle device to solve the problem that when the nozzle group expands, the thermal expansion gap cannot be controlled, and air leakage occurs when the airflow passes through the blades and channels, resulting in low steam passage efficiency and inability to fully utilize the steam kinetic energy.

[0006] Based on the above purpose, the present invention provides a high-efficiency steam turbine unit nozzle device, including a nozzle body, the nozzle body including a first nozzle group, a second nozzle group, a third nozzle group and a fourth nozzle group, the first nozzle group, the second nozzle group, the third nozzle group and the fourth nozzle group are all fan-shaped structures, and the first nozzle group, the second nozzle group, the third nozzle group and the fourth nozzle group are combined into a ring structure; The first nozzle group, the second nozzle group, the third nozzle group, and the fourth nozzle group all include an outer peripheral band, a first cascade block and an end cascade block are fixedly mounted on one side of the outer peripheral band, a plurality of groups of regulating stage stationary blades are distributed between the first cascade block and the end cascade block, and an inner peripheral band is fixedly mounted on the other side of the first cascade block and the end cascade block; A nozzle flow channel is formed between the outer band, the inner band and the multiple groups of regulating stage stationary blades, and positioning pins are arranged between the outer band, the inner band and the first block and the last block of the cascade; The first nozzle group, the second nozzle group, the third nozzle group and the fourth nozzle group are fixedly installed with sealing keys on the outside, and thermal expansion gaps are arranged at both ends of the first nozzle group, the second nozzle group, the third nozzle group and the fourth nozzle group, and a connecting shell is arranged in the thermal expansion gap.

[0007] Preferably, fixing columns are fixedly installed at both upper and lower ends of the connecting shell, a filter hole is opened on one side of the fixing column, a pipeline is sleeved on the outside of the fixing column, and joints are fixedly connected on both sides of the connecting shell, the joint is connected with one end of the pipeline, and the other end of the pipeline is connected with the filter hole; a nozzle is fixedly installed on one side of the first block and the last block of the blade, and the nozzle is connected with the joint.

[0008] Preferably, the pipeline is arranged in a spiral shape and is made of rubber material.

[0009] Preferably, a sealing gasket is provided on the outside of the connecting shell, and mounting holes corresponding to the joints are provided at the ends of the first nozzle group, the second nozzle group, the third nozzle group and the fourth nozzle group.

[0010] Preferably, at least ten groups of nozzle channels are provided inside the first nozzle group and the second nozzle group, at least twelve groups of nozzle channels are provided inside the third nozzle group, and at least fifteen groups of nozzle channels are provided inside the fourth nozzle group.

[0011] Preferably, the regulating stage stationary blades are arranged in an arc-shaped structure, a plurality of groups of regulating stage stationary blades are distributed equidistantly, and the angle between the regulating stage stationary blades and the outer peripheral band and the inner peripheral band is 34.5°.

[0012] Preferably, the sealing key is in interference fit with the first nozzle group, the second nozzle group, the third nozzle group, and the fourth nozzle group.

[0013] The beneficial effects of the present invention are as follows: high-temperature and high-pressure steam passes through the nozzle body. When the fluid flows inside the turbine, the steam passes through the first nozzle group, the second nozzle group, the third nozzle group, and the fourth nozzle group. Due to the gaps between the multiple nozzle groups, the high-temperature and high-pressure steam acts on the connecting shell to deform. At the same time, the thermal expansion gaps between the multiple nozzle groups also change and squeeze the connecting shell, generating a two-way force, thereby reducing the gaps between adjacent nozzle groups and avoiding air leakage when the air flows through the blades and channels; at the same time, the high-temperature and high-pressure steam acts on the rotor blades, and the regulating stage static blades with a certain curve curvature are used to fully reduce the steam resistance, so that the high-temperature and high-pressure steam can pass through the nozzle body smoothly, and the kinetic energy of steam can be maximized from a specific angle to do work, thereby directly acting on the blades, allowing the steam to pass efficiently and fully utilizing the kinetic energy of steam. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0015] Figure 1 It is a front view structural schematic diagram of the present invention as a whole; Figure 2 It is a cross-sectional expansion diagram of the upper half of the present invention at AA; Figure 3 It is a cross-sectional expansion diagram of the lower half of the present invention at AA; Figure 4 It is a schematic cross-sectional view of the structure at BB of the present invention; Figure 5 It is an enlarged structural schematic diagram of the mounting hole of the present invention; Figure 6 It is a schematic diagram of the internal structure of the connecting shell of the present invention.

[0016] The markings in the figure are: 1. regulating stage stationary blades; 2. first nozzle group; 3. second nozzle group; 4. third nozzle group; 5. fourth nozzle group; 6. outer belt; 7. inner belt; 9. first blade block; 10. last blade block; 11. nozzle flow channel; 12. positioning pin; 13. sealing key; 14. connecting shell; 15. nozzle; 16. sealing gasket; 17. pipeline; 18. joint; 19. filter hole; 20. fixing column; 21. mounting hole. DETAILED DESCRIPTION

[0017] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0018] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 and Figure 6As shown, a high-efficiency steam turbine unit nozzle device includes a nozzle body, the nozzle body includes a first nozzle group 2, a second nozzle group 3, a third nozzle group 4 and a fourth nozzle group 5, the first nozzle group 2, the second nozzle group 3, the third nozzle group 4 and the fourth nozzle group 5 are all fan-shaped structures, and the first nozzle group 2, the second nozzle group 3, the third nozzle group 4 and the fourth nozzle group 5 are combined into a ring structure; the first nozzle group 2, the second nozzle group 3, the third nozzle group 4 and the fourth nozzle group 5 all include an outer band 6, one side of the outer band 6 is fixedly installed with a blade head block 9 and a blade end block 10, the blade head block 9 and the blade end block 10 There are multiple groups of regulating stage stationary blades 1 distributed between them, and an inner circumferential belt 7 is fixedly installed on the other side of the first blade block 9 and the last blade block 10; a nozzle flow channel 11 is formed between the outer circumferential belt 6, the inner circumferential belt 7 and the multiple groups of regulating stage stationary blades 1, and positioning pins 12 are arranged between the outer circumferential belt 6, the inner circumferential belt 7 and the first blade block 9 and the last blade block 10; a sealing key 13 is fixedly installed on the outside of the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5, and thermal expansion gaps are arranged at both ends of the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5, and a connecting shell 14 is arranged in the thermal expansion gap.

[0019] In this embodiment, high-temperature and high-pressure steam passes through the nozzle body. When the fluid flows inside the turbine, the steam passes through the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5. Due to the gaps between the multiple nozzle groups, the high-temperature and high-pressure steam acts on the connecting shell 14 to cause deformation. At the same time, the thermal expansion gaps between the multiple nozzle groups also change and squeeze the connecting shell 14, generating a bidirectional force, thereby reducing the gaps between adjacent nozzle groups to avoid air leakage when the airflow passes through the blades and channels. At the same time, the high-temperature and high-pressure steam acts on the rotor blades, and a regulating stage static blade 1 with a certain curve curvature is used to fully reduce the steam resistance, so that the high-temperature and high-pressure steam can pass through the nozzle body smoothly, maximize the use of steam kinetic energy to do work from a specific angle, and thus directly act on the blades, so that the steam can pass efficiently and fully utilize the steam kinetic energy.

[0020] As an implementation method, Figure 6 As shown, fixing columns 20 are fixedly installed at both upper and lower ends of the connection shell 14, a filter hole 19 is opened on one side of the fixing column 20, a pipeline 17 is sleeved on the outside of the fixing column 20, and joints 18 are fixedly connected to both sides of the connection shell 14, the joint 18 is connected to one end of the pipeline 17, and the other end of the pipeline 17 is connected to the filter hole 19; a nozzle 15 is fixedly installed on one side of the blade head block 9 and the blade end block 10, and the nozzle 15 is connected to the joint 18.

[0021] In this embodiment, when the thermal expansion gap between multiple nozzle groups changes, the connecting shell 14 is squeezed, and at the same time, the pipe 17 in the connecting shell 14 is squeezed. The airflow in the pipe 17 then passes through the joint 18 and is pushed out through the nozzle 15 to act on the regulating stage static blades 1, thereby avoiding the long-term accumulation of dirt, dust or other impurities on the outside of the regulating stage static blades 1, preventing the increase of steam flow resistance, reducing flow rate and causing pressure loss.

[0022] As an implementation method, Figure 6 As shown, the pipeline 17 is arranged in a spiral shape and is made of rubber material.

[0023] In this embodiment, the spiral metal pipe 17 is used. When high-temperature and high-pressure steam enters, it expands due to heat and contracts due to cold, and expands outside the fixed column 20, thereby causing the connecting shell 14 to deform and abut against the adjacent nozzle group to reduce the gap.

[0024] As an implementation method, Figure 4 , Figure 5 and Figure 6 As shown, a sealing gasket 16 is disposed on the outside of the connecting shell 14 , and mounting holes 21 corresponding to the joints 18 are opened at the ends of the first nozzle group 2 , the second nozzle group 3 , the third nozzle group 4 , and the fourth nozzle group 5 .

[0025] In this embodiment, after the joint 18 is connected to the mounting hole 21, the joint 18 is connected to the nozzle 15, so that the airflow in the pipeline 17 passes through the joint 18 and is pushed out through the nozzle 15, acting on the regulating stage static blades 1, cleaning the accumulated dirt, dust or other impurities on the outside of the long regulating stage static blades 1.

[0026] As an implementation method, Figure 1 , Figure 2 , Figure 3 As shown, at least ten groups of nozzle channels 11 are opened inside the first nozzle group 2 and the second nozzle group 3, at least twelve groups of nozzle channels 11 are opened inside the third nozzle group 4, and at least fifteen groups of nozzle channels 11 are opened inside the fourth nozzle group 5.

[0027] In this embodiment, the steam flow is more evenly distributed through different flow channels inside the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5, thereby reducing the turbulence of the fluid and the local flow separation phenomenon.

[0028] As an implementation method, Figure 1 , Figure 2 , Figure 3 As shown, the regulating stage stationary blades 1 are arranged in an arc-shaped structure, a plurality of groups of regulating stage stationary blades 1 are distributed at equal intervals, and the angle between the regulating stage stationary blades 1 and the outer peripheral band 6 and the inner peripheral band 7 is 34.5°.

[0029] In this embodiment, high-temperature and high-pressure steam enters the steam turbine flow structure through the nozzle and acts on the rotor blades. The regulating stage stator blades 1 with a certain curvature are used to fully reduce the steam resistance, so that the high-temperature and high-pressure steam can smoothly pass through the nozzle group, and the kinetic energy of the steam can be maximized from a specific angle to work, thereby directly acting on the blades. The steam can pass efficiently and the kinetic energy of the steam can be fully utilized.

[0030] As an implementation method, Figure 4 , Figure 5 and Figure 6 As shown, the sealing key 13 is in interference fit with the first nozzle group 2 , the second nozzle group 3 , the third nozzle group 4 , and the fourth nozzle group 5 .

[0031] In this embodiment, the sealing key 13 is used to strengthen the overall sealing between the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5.

[0032] Working principle: When in use, high-temperature and high-pressure steam passes through the nozzle body. Since the nozzle body is formed by the combination of the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5, it enters the steam turbine flow structure and acts on the rotor blades. The regulating stage stator blades 1 with a certain curvature are used to fully reduce the steam resistance, so that the high-temperature and high-pressure steam can pass through the nozzle body smoothly, and the kinetic energy of steam can be maximized from a specific angle to do work, thereby directly acting on the blades, so that the steam can pass efficiently and fully utilize the kinetic energy of steam; At the same time, after the high-temperature and high-pressure steam enters the nozzle body, when the fluid flows inside the steam turbine, the steam passes through the first nozzle group 2, the second nozzle group 3, the third nozzle group 4, and the fourth nozzle group 5. Due to the gaps between the multiple nozzle groups, the high-temperature and high-pressure steam passes through the filter hole 19 and enters the pipeline 17. The spiral pipeline 17 expands after being heated, causing the connection shell 14 to deform. At the same time, the thermal expansion gaps between the multiple nozzle groups also change, squeezing the connection shell 14, generating a bidirectional force, thereby reducing the gaps between adjacent nozzle groups, and avoiding air leakage when the airflow passes through the blades and channels; At the same time, when the thermal expansion gap between multiple nozzle groups changes, the connecting shell 14 is squeezed, and the pipe 17 in the connecting shell 14 is squeezed at the same time. The airflow in the pipe 17 passes through the joint 18 and is pushed out through the nozzle 15 to act on the regulating stage static blades 1, thereby avoiding the accumulation of dirt, dust or other impurities on the outside of the regulating stage static blades 1 for a long time, preventing the increase of steam flow resistance, reducing flow rate and causing pressure loss.

[0033] Those skilled in the art should understand that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Under the concept of the present invention, the technical features in the above embodiments or different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the different aspects of the present invention as described above, which are not provided in detail for the sake of simplicity.

[0034] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-efficiency steam turbine unit nozzle device, comprising a nozzle body, wherein the nozzle body comprises a first nozzle group (2), a second nozzle group (3), a third nozzle group (4) and a fourth nozzle group (5), characterized in that: The first nozzle group (2), the second nozzle group (3), the third nozzle group (4), and the fourth nozzle group (5) are all fan-shaped structures, and the first nozzle group (2), the second nozzle group (3), the third nozzle group (4), and the fourth nozzle group (5) are combined together to form a ring structure; The first nozzle group (2), the second nozzle group (3), the third nozzle group (4), and the fourth nozzle group (5) all include an outer band (6), a first cascade block (9) and a last cascade block (10) being fixedly mounted on one side of the outer band (6), a plurality of groups of regulating stage stationary blades (1) being distributed between the first cascade block (9) and the last cascade block (10), and an inner band (7) being fixedly mounted on the other side of the first cascade block (9) and the last cascade block (10); A nozzle flow channel (11) is formed between the outer band (6), the inner band (7) and the plurality of groups of regulating stage stationary blades (1), and positioning pins (12) are provided between the outer band (6), the inner band (7) and the first blade block (9) and the last blade block (10); A sealing key (13) is fixedly installed on the outside of the first nozzle group (2), the second nozzle group (3), the third nozzle group (4) and the fourth nozzle group (5), and thermal expansion gaps are provided at both ends of the first nozzle group (2), the second nozzle group (3), the third nozzle group (4) and the fourth nozzle group (5), and a connecting shell (14) is provided in the thermal expansion gap.

2. A high-efficiency steam turbine unit nozzle device according to claim 1, characterized in that: The upper and lower ends of the connection shell (14) are fixedly mounted with fixing columns (20), one side of the fixing column (20) is provided with a filter hole (19), the outside of the fixing column (20) is sleeved with a pipeline (17), and the two sides of the connection shell (14) are respectively fixedly connected with joints (18), the joints (18) are connected to one end of the pipeline (17), and the other end of the pipeline (17) is connected to the filter hole (19); A nozzle (15) is fixedly mounted on one side of the blade cascade first block (9) and the blade cascade last block (10), and the nozzle (15) is connected to a joint (18).

3. A high-efficiency steam turbine unit nozzle device according to claim 2, characterized in that: The pipeline (17) is arranged in a spiral shape, and the pipeline (17) is a rubber material structure.

4. A high-efficiency steam turbine unit nozzle device according to claim 2, characterized in that: The outside of the connection shell (14) is provided with a sealing gasket (16), and the ends of the first nozzle group (2), the second nozzle group (3), the third nozzle group (4), and the fourth nozzle group (5) are provided with mounting holes (21) corresponding to the joint (18).

5. The high-efficiency steam turbine unit nozzle device according to claim 1, characterized in that: At least ten groups of nozzle flow channels (11) are provided inside the first nozzle group (2) and the second nozzle group (3), at least twelve groups of nozzle flow channels (11) are provided inside the third nozzle group (4), and at least fifteen groups of nozzle flow channels (11) are provided inside the fourth nozzle group (5).

6. The high-efficiency steam turbine unit nozzle device according to claim 1, characterized in that: The regulating stage stationary blades (1) are arranged in an arc-shaped structure, and the plurality of groups of regulating stage stationary blades (1) are distributed at equal intervals, and the angle between the regulating stage stationary blades (1) and the outer peripheral band (6) and the inner peripheral band (7) is 34.5°.

7. The high-efficiency steam turbine unit nozzle device according to claim 1, characterized in that: The sealing key (13) is in interference fit with the first nozzle group (2), the second nozzle group (3), the third nozzle group (4), and the fourth nozzle group (5).

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