Pre-twisted assembly type last-stage moving blade of steam turbine

Abstract

The invention discloses a steam turbine pre-twisting assembly type last-stage moving blade, and relates to the technical field of steam turbine blades, the steam turbine pre-twisting assembly type last-stage moving blade comprises an assembly main body, nine blade roots are uniformly arranged on the periphery of the assembly main body, a first limiting chamber is arranged on the outer surface of the front side of the assembly main body, and nine pressing pieces are arranged on the outer surface of the front side, corresponding to the blade roots, of the first limiting chamber; a fixing outer cover is arranged on the outer surface of the middle of the side, away from the assembling body, of the first limiting chamber, nine sets of bolt limiting holes are correspondingly formed in the outer surface of the fixing outer cover and the outer surface of the first limiting chamber, and corresponding fixing bolts are rotationally connected between the bolt limiting holes. A shroud ring connector is arranged on the outer surface of the side, away from the corresponding fixing bolt, of each blade molded line part, a blade base is arranged on the outer surface of the side, close to the corresponding pressing piece, of each blade root, the turbine moving blades can be effectively disassembled through cooperation of the structures, and the performance and reliability of the turbine are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of steam turbine blades, and in particular relates to a pre-twisted assembled last-stage moving blade for a steam turbine. Background Art

[0002] The pre-twisted assembled last stage moving blades of steam turbines are a special blade design, mainly used in industrial steam turbines. Its characteristic is that it adopts a pre-twisted assembled structure, which enables the blades to work more stably and reliably when subjected to the impact of high-temperature and high-pressure steam and centrifugal force. The pre-twisted design enables the blades to bend and deform during operation, thereby reducing the flow resistance when steam flows through the blades and improving the efficiency of the steam turbine. At the same time, this design can also reduce the stress level of the blades, reduce fatigue damage, and extend the service life. Therefore, the pre-twisted assembled last stage moving blades of steam turbines have broad application prospects in the field of steam turbines.

[0003] In the process of implementing this application, it was found that the technology has the following problems: the existing last-stage moving blades of the turbine are difficult to disassemble after installation, which increases the difficulty of maintenance and replacement, may lead to an increase in maintenance costs, and affect the overall operating efficiency and service life of the turbine. At the same time, the low transmission efficiency of the turbine leads to increased energy loss and reduced efficiency of the turbine.

[0004] For this purpose, a pre-twisted assembled last stage moving blade for a steam turbine is proposed. Summary of the invention

[0005] The purpose of the present invention is to increase the service life of a steam turbine and improve the performance and reliability of the steam turbine. The present application provides a pre-twisted assembled last stage moving blade for a steam turbine.

[0006] The technical solution adopted by the present invention is as follows: A pre-twisted assembled last-stage moving blade of a steam turbine comprises a lifting chamber, nine groups of blade roots are evenly arranged on the periphery of the assembly body, a first limiting chamber is arranged on the front outer surface of the assembly body, nine groups of pressing pieces are arranged on the front outer surface of the first limiting chamber corresponding to the blade root, a fixed outer cover is arranged on the outer surface of the middle part of the side of the first limiting chamber away from the assembly body, and nine groups of bolt limiting holes are opened on the fixed outer cover and the outer surface of the first limiting chamber correspondingly; Corresponding fixing bolts are rotatably connected between the bolt limiting holes, a blade profile portion is provided on the outer surface of each group of blade roots away from the assembly body, a shroud joint is provided on the outer surface of each group of blade profile portions away from the corresponding fixing bolts, and a blade base is provided on the outer surface of each group of blade roots close to the corresponding pressing piece.

[0007] Furthermore, the nine groups of blade bases are evenly distributed inside the assembly body, a pressing rod is provided on the outer surface of the other side of each group of pressing members, a limiting ring is provided around the outer periphery of the pressing rod, and a fourth spring is provided around the outer periphery of the pressing rod away from the limiting ring.

[0008] Furthermore, a longitudinal moving rod is arranged at the bottom of the pressing rod, and a pressing rod action hole is arranged on the outer surface of the top of the longitudinal moving rod, and the position of the pressing rod action hole matches that of the pressing rod.

[0009] Furthermore, a first rotation limiting seat is provided on the outer surface of the longitudinal moving rod at a side away from the pressing rod, and a rotation rod is rotationally connected between the first rotation limiting seats.

[0010] Furthermore, a second rotation limit seat is provided at the other end of the rotation rod, a pressure rod is provided below the rotation rod, a rotation limit ring is provided on the top of the pressure rod, and the second rotation limit seat is rotatably connected to the inner surface of the rotation limit ring on the outer surface.

[0011] Furthermore, a rotating chamber is provided inside each group of the pressing members, a spring fixing seat is provided on the outer surface of one side of each group of the rotating chamber close to the pressing member, a first spring is provided on the outer surface of the other side of the spring fixing seat, the other end of each group of the first spring is fixedly connected to the inner surface of the first limiting chamber, and a movable groove is provided on the periphery of each group of the longitudinal moving rods. A set of rotation limiting shafts is rotationally connected between each set of the rotation chambers and the first limiting chamber.

[0012] Furthermore, the outer surface of each group of the pressure rods is slidably connected to the outer surface of the corresponding rotating chamber, and the outer surface of each group of the rotating chambers on the side away from the pressing piece is fixedly connected to a spring chamber, the interior of the spring chamber includes a second spring, a second limit chamber and a pressure rod, the other end of the pressure rod is fixedly connected to the second limit chamber, the other outer surface of the second limit chamber is fixedly connected to the second spring, the other end of the second spring is fixedly connected to the inner wall of the spring chamber, the inner surface of one side of the second limit chamber is fixedly connected to a third spring, and the other outer surface of the third spring is provided with a rotation limit head.

[0013] Furthermore, both ends of each group of blade bases are provided with first limiting grooves, and the outer surface of one side of each group of the first limiting grooves close to the rotation limiting head is provided with second limiting grooves.

[0014] Furthermore, a driven gear is disposed inside the fixed outer cover, a driving gear is disposed inside the driven gear, a rotating shaft is disposed at the center of the driving gear, and the outer surface of the driven gear is meshed with the outer surface of the driving gear.

[0015] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are: 1. In the present invention, when the pre-twisted assembled last-stage moving blade of the steam turbine is disassembled, the corresponding pressing piece is pressed, and the pressing piece drives the pressing rod to move inward, and the pressing rod squeezes the corresponding longitudinal moving rod to move. Since the end of the longitudinal moving rod is rotatably connected to the rotating rod, and the spring chamber is connected to the outer surface of the rotating chamber, the movement of the longitudinal moving rod can drive the pressure-bearing rod to move outward, thereby causing the spring chamber to move outward. Since the rotating chamber forms a rotational relationship through the rotating limit shaft, the outward movement of the spring chamber causes the first spring to deform, so that the other end moves inward. At this time, the position restriction between the spring chamber and the first limiting groove is released, so that the corresponding blade can be easily disassembled.

[0016] 2. In the present invention, the shroud joint is located at the top of the blade, and is used to connect multiple blades into a whole, thereby increasing the rigidity and stability of the entire circle of blades. The blade profile part is manufactured and assembled according to the pre-twisted assembly scheme, and the blades are selected to optimize the steam flow and improve the working efficiency of the blades. The rotation of the rotating shaft can drive the driving gear on its periphery to rotate. Since the outer surface of the driving gear and the outer surface of the driven gear are meshed with each other, the rotation of the driving gear drives the corresponding fixed outer cover to rotate, thereby achieving the purpose of starting multiple groups of moving blades. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the present invention; Figure 2 It is a schematic diagram of the structure of the moving blade of the present invention; Figure 3 It is a structural schematic diagram of the rotating mode of the moving blades of the present invention; Figure 4 It is a structural schematic diagram of the blade disassembly assembly of the present invention; Figure 5 It is a partial structural schematic diagram of the blade disassembly assembly of the present invention; Figure 6 It is a cross-sectional view of the blade limiting chamber of the present invention.

[0018] In the figure: 1-assembly body; 2-fixed outer cover; 3-fixed bolt; 4-blade profile part; 5-shroud joint; 6-first limit chamber; 7-pressing member; 8-first spring; 9-spring fixing seat; 10-rotation chamber; 11-rotation limit shaft; 12-first limit groove; 13-blade base; 14-second limit groove; 15-limiting protrusion; 16-spring chamber; 17-second spring; 18-second limit chamber; 1 9-third spring; 20-pressure rod; 21-pressing rod; 22-limiting ring; 23-fourth spring; 24-pressure rod action hole; 25-first rotation limiting seat; 26-rotation rod; 27-second rotation limiting seat; 28-rotation limiting ring; 29-longitudinal moving rod; 30-bolt limiting hole; 31-driven gear; 32-driving gear; 33-rotation shaft; 34-blade root; 35-movable groove; 36-rotation limiting head. DETAILED DESCRIPTION

[0019] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in combination with the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Example

[0020] Reference Figure 1-Figure 6 A pre-twisted assembled last-stage moving blade of a steam turbine comprises a lifting body 1, nine groups of blade roots 34 are evenly arranged on the periphery of the assembly body 1, a first limiting chamber 6 is arranged on the front outer surface of the assembly body 1, nine groups of pressing pieces 7 are arranged on the front outer surface of the first limiting chamber 6 corresponding to the blade root 34, a fixed outer cover 2 is arranged on the middle outer surface of the side of the first limiting chamber 6 away from the assembly body 1, nine groups of bolt limiting holes 30 are correspondingly opened on the outer surfaces of the fixed outer cover 2 and the first limiting chamber 6, corresponding fixing bolts 3 are rotatably connected between the bolt limiting holes 30, a blade profile part 4 is arranged on the outer surface of each group of blade roots 34 away from the assembly body 1, a shroud joint 5 is arranged on the outer surface of each group of blade profile parts 4 away from the corresponding fixing bolts 3, and a blade base 13 is arranged on the outer surface of each group of blade roots 34 close to the corresponding pressing piece 7. Specifically, through the cooperation of the above structures, the moving blades of the steam turbine can be effectively disassembled to improve the performance and reliability of the steam turbine.

[0021] Reference Figure 1-Figure 6, nine groups of blade bases 13 are evenly distributed inside the assembly body 1, and a pressing rod 21 is provided on the outer surface of the other side of each group of pressing parts 7. A limiting ring 22 is provided around the outer periphery of the pressing rod 21, and a fourth spring 23 is provided around the outer periphery of the pressing rod 21 away from the limiting ring 22. Specifically, nine groups of blade bases 13 are evenly distributed inside the assembly body 1, and a pressing rod 21 is provided next to the pressing part 6, and a limiting ring 22 and a fourth spring 23 are provided on its outer periphery to ensure stable pressing and smooth operation, thereby improving overall performance. A longitudinal moving rod 29 is provided at the bottom of the pressing rod 21, and a pressing rod action hole 24 is provided on the outer surface of the top of the longitudinal moving rod 29. The pressing rod action hole 24 matches the position of the pressing rod 21. Specifically, a longitudinal moving rod 29 is provided at the bottom of the pressing rod 21, and a pressing rod action hole is provided at the top of the rod to match the position of the pressing rod 21. This design ensures accurate transmission of the pressing action and improves operating efficiency and stability.

[0022] Reference Figure 1-Figure 6 The outer surface of the longitudinal moving rod 29 away from the pressing rod 21 is provided with a first rotation limit seat 25, and the first rotation limit seat 25 is rotatably connected with the rotating rod 26. Specifically, the spring chamber 16 is connected to the outer surface of the rotating chamber 10. The movement of the longitudinal moving rod 29 can drive the pressure rod 20 to move outward, thereby causing the spring chamber 16 to move outward. A second rotation limit seat 27 is provided at the other end of the rotating rod 26. The pressure rod 20 is provided below the rotating rod 26. A rotation limit ring 28 is provided at the top of the pressure rod 20. The second rotation limit seat 27 is rotatably connected with the inner surface of the outer surface rotation limit ring 28. Specifically, the pressing rod 21 squeezes the corresponding longitudinal moving rod 29 to move, and the end of the longitudinal moving rod 29 is rotatably connected with the rotating rod 26.

[0023] Reference Figure 1-Figure 6A rotating chamber 10 is provided inside each group of pressing members 7, a spring fixing seat 9 is provided on the outer surface of each group of rotating chambers 10 close to the pressing member 7, a first spring 8 is provided on the outer surface of the other side of the spring fixing seat 9, the other end of each group of first springs 8 is fixedly connected to the inner surface of the first limiting chamber 6, a movable groove 35 is provided on the periphery of each group of longitudinal moving rods 29, and a group of rotating limiting shafts 11 are rotatably connected to each group of rotating chambers 10 and the first limiting chamber 6. Specifically, the longitudinal moving rod 29 is provided with an movable groove 35 on the periphery, and the rotating chamber 10 and the limiting chamber 6 are provided with a rotating limiting shaft 11, to ensure that the structure is stable and flexible. The outer surface of each group of pressure rods 20 is slidably connected to the outer surface of the corresponding rotating chamber 10, and the outer surface of each group of rotating chambers 10 on the side away from the pressing member 7 is fixedly connected to a spring chamber 16. The spring chamber 16 includes a second spring 17, a second limiting chamber 18 and a pressure rod 20. The other end of the pressure rod 20 is fixedly connected to the second limiting chamber 18, and the other outer surface of the second limiting chamber 18 is fixedly connected to the second spring 17. The other end of the second spring 17 is fixedly connected to the inner wall of the spring chamber 16. The inner surface of one side of the second limiting chamber 18 is fixedly connected to a third spring 19, and the other outer surface of the third spring 19 is provided with a rotation limiting head 36. Specifically, the pressure rod 20 is slidably connected to the rotating chamber 10, the spring chamber 16 contains the second spring 17, the second limiting chamber 18 and the pressure rod 20, and the second limiting chamber 18 is connected to the third spring 19 and the rotation limiting head 36 to ensure a stable and flexible structure.

[0024] Both ends of each blade base 13 are provided with a first limiting groove 12, and the outer surface of each first limiting groove 12 near the rotating limiting head 36 is provided with a second limiting groove 14. Specifically, the first limiting groove 12 and the spring chamber 16 form a position limit, and the second limiting groove 14 and the limiting protrusion form a position limit. A driven gear 31 is provided inside the fixed outer cover 2, and a driving gear 32 is provided inside the driven gear 31. A rotating shaft 33 is provided at the center of the driving gear 32, and the outer surface of the driven gear 31 and the outer surface of the driving gear 32 are meshed with each other. Specifically, the rotation of the rotating shaft 33 can drive the driving gear 32 on its periphery to rotate. Since the outer surface of the driving gear 32 and the outer surface of the driven gear 31 are meshed with each other, the rotation of the driving gear 32 drives the corresponding fixed outer cover 2 to rotate, thereby achieving the purpose of starting multiple groups of moving blades.

[0025] The implementation principle of the embodiment of the pre-twisted assembled last stage moving blade of the steam turbine of the present application is as follows: When the pre-twisted assembled last-stage moving blades of the steam turbine are disassembled, the corresponding pressing piece 7 is pressed, and the pressing piece 7 drives the pressing rod 21 to move inward, and the pressing rod 21 squeezes the corresponding longitudinal moving rod 29 to move. Since the end of the longitudinal moving rod 29 is rotatably connected to the rotating rod 26, and the spring chamber 16 is connected to the outer surface of the rotating chamber 10, the movement of the longitudinal moving rod 29 can drive the pressure rod 20 to move outward, thereby causing the spring chamber 16 to move outward. Since the rotating chamber 10 forms a rotational relationship through the rotating limit shaft 11, the outward movement of the spring chamber 16 causes the first spring 8 to deform, so that the other end of 10 moves inward. At this time, the position restriction between the spring chamber 16 and the first limiting groove 12 is released, so that the corresponding blade can be easily disassembled.

[0026] On the other hand, the shroud joint 5 is located at the top of the blade, and is used to connect multiple blades into a whole, thereby increasing the rigidity and stability of the entire circle of blades. The blade profile portion 4 is manufactured and selected according to a pre-twisted assembly scheme for assembly, thereby optimizing steam flow and improving the working efficiency of the blades. The rotation of the rotating shaft 33 can drive the driving gear 32 on its periphery to rotate. Since the outer surface of the driving gear 32 and the outer surface of the driven gear 31 are meshed with each other, the rotation of the driving gear 32 drives the corresponding fixed outer cover 2 to rotate, thereby achieving the purpose of starting multiple groups of moving blades.

[0027] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A pre-twisted assembled last-stage moving blade for a steam turbine, comprising an assembly body (1), Features: Nine groups of blade roots (34) are evenly arranged on the periphery of the assembly body (1); a first limiting chamber (6) is arranged on the front outer surface of the assembly body (1); nine groups of pressing members (7) are arranged on the front outer surface of the first limiting chamber (6) corresponding to the blade root (34); a fixed outer cover (2) is arranged on the middle outer surface of a side of the first limiting chamber (6) away from the assembly body (1); nine groups of bolt limiting holes (30) are correspondingly opened on the outer surfaces of the fixed outer cover (2) and the first limiting chamber (6); The bolt limiting holes (30) are rotatably connected with corresponding fixing bolts (3), and the outer surface of each group of blade roots (34) away from the assembly body (1) is provided with a blade profile portion (4), and the outer surface of each group of blade profile portions (4) away from the corresponding fixing bolts (3) is provided with a shroud joint (5), and the outer surface of each group of blade roots (34) close to the corresponding pressing member (7) is provided with a blade base (13).

2. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 1, Features: Nine groups of blade bases (13) are evenly distributed inside the assembly body (1), and a pressing rod (21) is provided on the outer surface of the other side of each group of pressing members (7). A limiting ring (22) is provided around the outer periphery of the pressing rod (21), and a fourth spring (23) is provided around the outer periphery of the pressing rod (21) away from the limiting ring (22).

3. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 2, Features: A longitudinal moving rod (29) is provided at the bottom of the pressing rod (21), and a pressing rod action hole (24) is provided on the top outer surface of the longitudinal moving rod (29), wherein the positions of the pressing rod action hole (24) and the pressing rod (21) match each other.

4. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 3, Features: A first rotation limit seat (25) is provided on the outer surface of a side of the longitudinal moving rod (29) away from the pressing rod (21), and a rotation rod (26) is rotationally connected between the first rotation limit seats (25).

5. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 4, Features: A second rotation limit seat (27) is provided at the other end of the rotation rod (26), a pressure rod (20) is provided below the rotation rod (26), a rotation limit ring (28) is provided at the top of the pressure rod (20), and the second rotation limit seat (2) is rotatably connected to the inner surface of the rotation limit ring (28) through the outer surface.

6. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 5, Features: Each group of the pressing members (7) is provided with a rotating chamber (10) inside, and a spring fixing seat (9) is provided on the outer surface of one side of each group of the rotating chamber (10) close to the pressing member (7), and a first spring (8) is provided on the outer surface of the other side of the spring fixing seat (9), and the other end of the first spring (8) of each group is fixedly connected to the inner surface of the first limiting chamber (6), and a movable groove (35) is provided on the periphery of each group of the longitudinal moving rods (29). Each set of the rotating chambers (10) is rotatably connected to the first limiting chamber (6) by a set of rotating limiting shafts (11).

7. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 6, Features: The outer surface of each group of the pressure-bearing rods (20) is slidably connected to the outer surface of the corresponding rotating chamber (10); the outer surface of each group of the rotating chambers (10) on the side away from the pressing member (7) is fixedly connected to a spring chamber (16); the spring chamber (16) includes a second spring (17), a second limit chamber (18) and a pressure-bearing rod (20); the other end of the pressure-bearing rod (20) is fixedly connected to the second limit chamber (18); the other outer surface of the second limit chamber (18) is fixedly connected to the second spring (17); the other end of the second spring (17) is fixedly connected to the inner wall of the spring chamber (16); the inner surface of one side of the second limit chamber (18) is fixedly connected to a third spring (19); the other outer surface of the third spring (19) is provided with a rotation limit head (36).

8. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 1, Features: Both ends of each group of blade bases (13) are provided with first limiting grooves (12), and the outer surface of each group of first limiting grooves (12) on a side close to the rotation limiting head (36) is provided with a second limiting groove (14).

9. A pre-twisted assembled last stage moving blade for a steam turbine as claimed in claim 1, Features: A driven gear (31) is arranged inside the fixed outer cover (2), a driving gear (32) is arranged inside the driven gear (31), a rotating shaft (33) is arranged at the center of the driving gear (32), and the outer surface of the driven gear (31) meshes with the outer surface of the driving gear (32).

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