Protection equipment for blade root bolt of wind driven generator

Abstract

The invention discloses a wind driven generator blade root bolt protection device which comprises a hub and three blades, three first assembly plates are rotatably mounted on the outer side of the hub, four first thread grooves are formed in each of the three first assembly plates, second assembly plates are fixedly mounted at the bottoms of the three blades, and the third assembly plates are fixedly mounted on the outer side of the hub. Four first threaded holes are formed in the second assembling plate, and the positions of the four first threaded holes correspond to the positions of the four first threaded grooves correspondingly. The convex cap is connected to the end portion of the bolt in a sleeved mode, when the blade operates for a long time to cause fatigue fracture of the bolt, through the design of threaded connection of the nut and the threaded ring, it is guaranteed that even if the bolt is fractured, the residual portion of the bolt does not fall off at will, and therefore the risk that the bolt falls off to cause serious smashing damage to the lower portion or peripheral equipment is avoided; the safety performance of equipment is greatly improved, the area of the joint face of the nut and the second assembly plate is increased through threaded connection, and the stress borne by the bolt on the joint face of the nut and the second assembly plate is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of wind turbine generators, in particular to a protective device for bolts at the root of a wind turbine generator blade. Background Art

[0002] A wind turbine, also known as a windmill or wind turbine, is a mechanical device that converts the kinetic energy of wind into electrical energy. It is one of the renewable energy technologies that aims to reduce dependence on traditional fossil fuels and provide a sustainable and environmentally friendly solution for global energy supply. The working principle of a wind turbine is relatively simple: the wind rotor rotates under the action of wind, and this rotational motion increases the speed of rotation through a speed increaser to enable the generator to generate electricity. According to current windmill technology, power generation can begin at a breeze speed of about three meters per second.

[0003] At present, the bolt connection of wind turbine blades is mainly connected by studs, one end of which is screwed into the blade through the hub, and the other end is fixed to the hub by a nut. Under the influence of cyclic stress, the blade bolts are most likely to produce stress concentration at the connection between the hub and the nut, causing the blade bolts to break. The broken bolts rotate with the hub in the hub, often damaging the equipment and breaking the connecting wires, which has a great impact on the safe operation of the wind turbine. Summary of the invention

[0004] The object of the present invention is to provide a protection device for the root bolts of a wind turbine blade to solve the problems raised in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a protective device for the root bolts of wind turbine blades, comprising a hub and three blades, three assembly plates 1 are rotatably mounted on the outer side of the hub, four threaded grooves 1 are respectively provided inside the three assembly plates 1, and assembly plates 2 are fixedly mounted on the bottoms of the three blades, four threaded holes 1 are provided inside the three assembly plates 2, and the positions of the four threaded holes 1 respectively correspond to the positions of the four threaded grooves 1, and bolts are threadedly connected inside the corresponding thread grooves 1 and threaded holes 1, a nut is threadedly connected on the outer side of one end of the bolt, a threaded ring is threadedly connected on the outer side of the nut, a convex cap is fixedly mounted on the top of the threaded ring, and the convex cap is sleeved on the outer side of the end of the bolt.

[0006] Preferably, the angle between two adjacent thread grooves 1 is forty-five degrees, the angle between two adjacent thread holes 1 is forty-five degrees, two thread grooves 2 are provided inside the assembly plate 1, the angle between the two thread grooves 2 is sixty degrees, and the two thread grooves 2 are symmetrically located on both sides of one of the thread grooves 1, two thread holes 2 are provided inside the assembly plate 2, the angle between the two thread holes 2 is sixty degrees, and the two thread holes 2 are symmetrically located on both sides of one of the thread holes 1, the two thread grooves 2 correspond to the positions of the two thread holes 2 respectively, and the corresponding thread grooves 2 and thread holes 2 are both threadedly connected with bolts.

[0007] Preferably, a magnet ring 1 is fixedly installed on the bottom of the threaded ring, a movable ring groove 1 is provided inside the assembly plate 2, a magnet ring 2 is slidably installed inside the movable ring groove 1, the magnetic poles of the magnet ring 2 and the opposite surface of the magnet ring 1 are the same, a reinforcing rod is fixedly installed on the bottom of the magnet ring 2, a circular slot is provided inside the side of the assembly plate 2 away from the blade, a circular socket is provided on the side of the assembly plate 1 away from the hub, the position of the circular socket corresponds to the position of the circular slot, and the position of the reinforcing rod corresponds to the position of the circular socket and the circular slot.

[0008] Preferably, a sliding column is fixedly installed inside the movable ring groove 1, and the magnet ring 2 is slidably installed on the outside of the sliding column.

[0009] Preferably, a spring 1 is fixedly mounted on the top of the magnet ring 2, one end of the spring 1 away from the magnet ring 2 is fixedly connected to the top of the inner cavity of the movable ring groove 1, and the spring is installed in a sleeve on the outside of the sliding column.

[0010] Preferably, a movable ring groove 2 is opened inside the assembly plate 1, a magnet ring 3 is slidably installed inside the movable ring groove 2, a spring 2 is fixedly installed at the bottom of the magnet ring 3, and one end of the spring 2 away from the magnet ring 3 is fixedly connected to the bottom of the inner cavity of the movable ring groove 2.

[0011] Preferably, a central plug column is fixedly installed inside the thread groove one and the thread groove two, and a central plug hole is opened inside the bottom of the bolt, and the position of the central plug hole corresponds to the position of the central plug column.

[0012] Preferably, an annular groove is provided inside the center socket, a movable circular groove is provided inside the center column, a movable iron block is slidably installed inside the movable circular groove, a connecting column is fixedly installed at the bottom of the movable iron block, four inclined blocks 1 are fixedly installed at the bottom of the connecting column, inclined surfaces of the four inclined blocks 1 are slidably installed with inclined blocks 2, and the ends of the inclined blocks 2 away from the inclined block 1 are fixedly installed with push-out blocks.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. By sleeve-fitting the convex cap on the end of the bolt, when the bolt is fatigued and broken due to long-term operation of the blade, the threaded connection design of the nut and the threaded ring not only ensures that even if the bolt breaks, its remaining part will not fall off at will, thereby avoiding the risk of serious damage to the lower or surrounding equipment caused by the falling bolt, greatly improving the safety performance of the equipment. This threaded connection increases the joint surface area between the nut and the second assembly plate, and reduces the stress on the bolt at the joint surface between the nut and the second assembly plate, which can disperse and reduce the stress concentration phenomenon on the bolt at the joint surface between the nut and the second assembly plate. Even if the bolt is gradually worn out due to long-term operation or suffers from sudden high-load impact, the connection between the nut and the second assembly plate can still maintain sufficient strength and stability, effectively delaying or preventing further damage to the bolt;

[0015] 2. In addition, after the assembly plate 2 is installed on the surface of the assembly plate 1, the thread groove 2 and the thread hole 2 can be made to correspond to each other, and then the bolt can be threadedly connected to the inner side of the thread groove 2 and the thread hole 2. The position of the thread groove 2 and the thread hole 2 is reinforced to disperse the stress applied to the place when the blade rotates. These stresses are more evenly dispersed to three points, reducing the possibility of stress concentration. The bolt can also maintain sufficient strength and stability, avoiding the risk of breakage caused by excessive stress;

[0016] 3. When the threaded ring is threadedly connected to the outside of the nut, the magnet ring 1 can be driven to move toward the side close to the assembly plate 2, thereby exerting a repulsive force on the magnet ring 2, so that the magnet ring 2 moves downward on the inner side of the movable ring groove 1, thereby pushing the reinforcement plug rod to move downward, so that the reinforcement plug rod is inserted into the inside of the circular socket and the circular slot, thereby reinforcing the connection position of the assembly plate 2 and the assembly plate 1. On the one hand, the stress on the bolt can be dispersed and the bolt can be protected. On the other hand, the assembly plate 1 and the assembly plate 2 can still be assembled together after the bolt breaks. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention.

[0018] Figure 2 It is a schematic diagram of a partially cutaway three-dimensional structure of the present invention.

[0019] Figure 3 For the present invention Figure 2 Enlarged structural diagram at A in the middle.

[0020] Figure 4 It is a schematic diagram of the three-dimensional structure of the wheel hub of the present invention.

[0021] Figure 5 This is a schematic diagram of the cross-sectional structure of the center plug post of the present invention.

[0022] Figure 6 It is a schematic diagram of the partial split structure of the present invention.

[0023] Figure 7 It is a schematic diagram of the three-dimensional structure of the blade of the present invention.

[0024] In the figure: 1. hub; 2. blade; 3. assembly plate 1; 4. threaded groove 1; 5. center plug post; 6. circular socket; 7. moving iron block; 8. moving circular groove; 9. connecting post; 10. tilting block 1; 11. push-out block; 12. tilting block 2; 13. threaded hole 1; 14. circular slot; 15. bolt; 16. center plug post; 17. nut; 18. magnet ring 1; 19. threaded ring; 20. convex cap; 21. assembly plate 2; 22. moving ring groove 1; 23. sliding post; 24. spring 1; 25. magnet ring 2; 26. reinforcement plug rod; 27. magnet ring 3; 28. moving ring groove 2; 29. ​​spring 2; 30. threaded groove 2; 31. threaded hole 2. DETAILED DESCRIPTION

[0025] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only 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.

[0026] See also Figure 1-Figure 7The present invention provides a technical solution: a protective device for the root bolts of a wind turbine blade, comprising a hub 1 and three blades 2, three assembly plates 3 are rotatably mounted on the outer side of the hub 1, four threaded grooves 4 are provided inside the three assembly plates 3, assembly plates 21 are fixedly mounted on the bottoms of the three blades 2, four threaded holes 13 are provided inside the assembly plates 21, the positions of the four threaded holes 13 correspond to the positions of the four threaded grooves 4, and bolts 15 are threadedly connected to the corresponding threaded grooves 4 and threaded holes 13, a nut 17 is threadedly connected to the outer side of one end of the bolt 15, a threaded ring 19 is threadedly connected to the outer side of the nut 17, a convex cap 20 is fixedly mounted on the top of the threaded ring 19, and the convex cap 20 is sleeved on the outer side of the end of the bolt 15, the angle between two adjacent thread grooves 4 is forty-five degrees, the angle between two adjacent thread holes 13 is forty-five degrees, the interior of the assembly plate 3 is provided with two thread grooves 230, the angle between the two thread grooves 230 is sixty degrees, and the two thread grooves 230 are symmetrically located on both sides of one of the thread grooves 4, the interior of the assembly plate 21 is provided with two thread holes 231, the angle between the two thread holes 231 is sixty degrees, and the two thread holes 231 are symmetrically located on both sides of one of the thread holes 13, the two thread grooves 230 correspond to the positions of the two thread holes 231 respectively, and the corresponding thread grooves 230 and thread holes 231 are both threadedly connected with bolts 15.

[0027] The working principle of the above technical solution is as follows: first, the assembly plate 21 at one end of the blade 2 is brought into contact with the assembly plate 3 on the outside of the hub 1, and the thread groove 4 is aligned with the threaded hole 13, and then the bolt 15 is threadedly connected to the inside of the threaded hole 13 and the thread groove 4, and the nut 17 is threadedly connected to the outside of the bolt 15, thereby completing the assembly between the assembly plate 21 and the assembly plate 3, and completing the assembly between the hub 1 and the blade 2, and then the threaded ring 19 can be threadedly connected to the outside of the nut 17, and the convex cap 20 can be sleeved on the end of the bolt 15. When the blade 2 operates for a long time and causes the bolt 15 to fatigue and break, the threaded connection design of the nut 17 and the threaded ring 19 not only ensures that even if the bolt 15 breaks, its remaining part will not fall off at will, thereby avoiding the risk of serious damage to the lower or surrounding equipment caused by the falling of the bolt 15, greatly improving the safety performance of the equipment, and this threaded connection increases the joint surface of the nut 17 and the assembly plate 21 The stress concentration phenomenon on the bolt 15 at the joint surface between the nut 17 and the assembly plate 21 can be dispersed and reduced. Even if the bolt 15 is gradually worn out due to long-term operation or is subjected to sudden high-load impact, the connection between the nut 17 and the assembly plate 21 can still maintain sufficient strength and stability, effectively delaying or preventing further damage to the bolt 15. In addition, after the assembly plate 21 is installed on the surface of the assembly plate 3, the thread groove 2 30 and the thread hole 2 31 can be made to correspond to each other, and then the bolt 15 can be threadedly connected to the inner side of the thread groove 2 30 and the thread hole 2 31, and the position of the thread groove 2 30 and the thread hole 2 31 is reinforced, so as to disperse the stress applied to the place when the blade 2 rotates. These stresses are more evenly dispersed to three points, reducing the possibility of stress concentration. The bolt 15 can also maintain sufficient strength and stability, avoiding the risk of breakage caused by excessive stress.

[0028] In another embodiment, Figure 1-Figure 7As shown, a magnet ring 18 is fixedly installed at the bottom of the threaded ring 19, a movable ring groove 22 is provided inside the assembling plate 21, a magnet ring 25 is slidably installed inside the movable ring groove 22, the magnetic poles of the magnet ring 25 and the opposite side of the magnet ring 18 are the same, a reinforcing plug rod 26 is fixedly installed at the bottom of the magnet ring 25, a circular slot 14 is provided inside the assembling plate 21 away from the blade 2, a circular socket 6 is provided on the side of the assembling plate 3 away from the hub 1, the position of the circular socket 6 corresponds to the position of the circular slot 14, the position of the reinforcing plug rod 26 corresponds to the position of the circular socket 6 and the circular slot 14, a sliding column 23 is fixedly installed inside the movable ring groove 22, the magnet ring 25 is slidably installed on the outside of the sliding column 23, a spring 24 is fixedly installed on the top of the magnet ring 25, one end of the spring 24 away from the magnet ring 25 is fixedly connected to the top of the inner cavity of the movable ring groove 22, and the spring 24 is sleeved and installed on the outside of the sliding column 23.

[0029] When the threaded ring 19 is threadedly connected to the outer side of the nut 17, the magnet ring 18 can be driven to move toward the side close to the assembly plate 21, thereby exerting a repulsive force on the magnet ring 25, so that the magnet ring 25 moves downward on the inner side of the movable ring groove 12, thereby pushing the reinforcement plug 26 to move downward, so that the reinforcement plug 26 is inserted into the circular socket 6 and the circular slot 14, thereby reinforcing the connection position of the assembly plate 21 and the assembly plate 3, which can reduce the stress on the bolt 15. On the one hand, the force is dispersed to protect the bolt 15. On the other hand, after the bolt 15 is broken, the assembly plate 1 3 and the assembly plate 2 21 can still be assembled together, so that the hub 1 and the blade 2 are still assembled together. In addition, after the threaded ring 19 is removed from the outside of the nut 17, the magnet ring 18 no longer exerts a repulsive force on the magnet ring 25. Under the action of the elastic force of the spring 1 24, the magnet ring 25 can be pulled upward to reset, so that the reinforcement rod 26 can be disengaged from the inside of the threaded groove 4, without affecting the disassembly and maintenance of the blade 2.

[0030] In another embodiment, Figure 1-Figure 7As shown, a movable annular groove 28 is provided inside the assembly plate 1 3, a magnet ring 3 27 is slidably installed inside the movable annular groove 28, a spring 29 is fixedly installed at the bottom of the magnet ring 3 27, and one end of the spring 29 away from the magnet ring 3 27 is fixedly connected to the bottom of the inner cavity of the movable annular groove 28, a central plug post 5 is fixedly installed inside the thread groove 1 4 and the thread groove 2 30, a central plug hole 16 is provided inside the bottom of the bolt 15, and the position of the central plug hole 16 corresponds to the position of the central plug post 5, and an annular groove is provided inside the central plug hole 16. A movable circular groove 8 is provided inside the core plug column 5, and a movable iron block 7 is slidably installed inside the movable circular groove 8. A connecting column 9 is fixedly installed at the bottom of the movable iron block 7, and four inclined blocks 10 are fixedly installed at the bottom of the connecting column 9. Inclined surfaces of the four inclined blocks 10 are all slidably installed with inclined blocks 2 12. The inclined surfaces of the inclined blocks 10 are provided with T-shaped grooves, and the inclined surfaces of the inclined blocks 2 12 are fixedly installed with T-shaped sliders, which are slidably installed inside the T-shaped grooves, and the ends of the inclined blocks 2 12 away from the inclined blocks 10 are fixedly installed with push-out blocks 11.

[0031] When the bolt 15 is threadedly connected to the thread groove 1 4 and the thread groove 2 30, the center plug column 5 can be inserted into the center socket 16, and when the reinforcement plug rod 26 moves downward, the magnet ring 3 27 can be pushed to move downward in the movable ring groove 2 28, thereby driving the movable iron block 7 to move downward in the movable circular groove 8 through the magnetic force, thereby pushing the four inclined blocks 10 to move downward through the connecting column 9, and making the T-shaped slider move upward along the T-shaped slide groove, thereby pushing the push-out block 11 out of the center plug column 5 through the inclined block 10 and the inclined block 2 12, and inserting it into the annular groove inside the center socket 16, limiting and fixing the end of the bolt 15, strengthening the assembly effect between the hub 1 and the blade 2, and when the reinforcement plug rod 26 breaks, the magnet ring 3 27 can adsorb the reinforcement plug rod 26 to prevent the reinforcement plug rod 26 from falling and damaging the equipment.

[0032] Working principle: First, make the assembly plate 21 at one end of the blade 2 contact with the assembly plate 3 on the outside of the hub 1, and align the thread groove 4 with the threaded hole 13, then thread the bolt 15 into the threaded hole 13 and the thread groove 4, and thread the nut 17 into the outside of the bolt 15, so as to complete the assembly between the assembly plate 21 and the assembly plate 3, and realize the assembly between the hub 1 and the blade 2, then the thread ring 19 can be threaded into the outside of the nut 17, and the convex cap 20 can be sleeved on the end of the bolt 15, and after the assembly plate 21 is installed on the surface of the assembly plate 3, the thread groove 30 can be made to correspond to the threaded hole 31, and then The bolt 15 can be threadedly connected to the inner side of the thread groove 2 30 and the thread hole 2 31, and the position of the thread groove 2 30 and the thread hole 2 31 can be reinforced to disperse the stress applied to the position when the blade 2 rotates. When the thread ring 19 is threadedly connected to the outer side of the nut 17, the magnet ring 18 can be driven to move to the side close to the assembly plate 21, thereby exerting a repulsive force on the magnet ring 25, so that the magnet ring 25 moves downward on the inner side of the movable ring groove 1 22, thereby pushing the reinforcement plug rod 26 to move downward, so that the reinforcement plug rod 26 is inserted into the circular socket 6 and the circular slot 14, thereby reinforcing the connection position of the assembly plate 21 and the assembly plate 3. On the one hand, The stress on the bolt 15 is dispersed to protect the bolt 15. On the other hand, after the bolt 15 breaks, the assembly plate 1 3 and the assembly plate 2 21 can still be assembled together, so that the hub 1 and the blade 2 are still assembled together. In addition, after the threaded ring 19 is removed from the outside of the nut 17, the magnet ring 18 no longer exerts a repulsive force on the magnet ring 25. Under the action of the elastic force of the spring 1 24, the magnet ring 25 can be pulled upward to reset, so that the reinforcement rod 26 is disengaged from the inside of the thread groove 1 4, which does not affect the disassembly and maintenance of the blade 2. When the bolt 15 is threadedly connected to the inside of the thread groove 1 4 and the thread groove 2 30, the center plug column 5 can be inserted into the inside of the center plug hole 16, and the reinforcement plug rod 2 When 6 moves downward, it can push the magnet ring three 27 to move downward inside the movable ring groove two 28, thereby driving the movable iron block 7 to move downward inside the movable circular groove 8 through the magnetic force, thereby pushing the four tilting blocks one 10 to move downward through the connecting column 9, and making the T-shaped slider move upward along the T-shaped slide groove, so that the push-out block 11 is pushed out of the center plug column 5 through the tilting block one 10 and the tilting block two 12, and inserted into the annular groove inside the center plug hole 16, to limit and fix the end of the bolt 15, and strengthen the assembly effect between the hub 1 and the blade 2. In addition, when the reinforcement plug rod 26 is broken, the magnet ring three 27 can adsorb the reinforcement plug rod 26 to prevent the reinforcement plug rod 26 from falling and damaging the equipment.

[0033] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A protective device for bolts at the root of a wind turbine blade, comprising a hub (1) and three blades (2), characterized in that: Three assembly plates (3) are rotatably mounted on the outer side of the hub (1), and four threaded grooves (4) are provided inside the three assembly plates (3). Assembly plates (21) are fixedly mounted on the bottoms of the three blades (2), and four threaded holes (13) are provided inside the assembly plates (21). The positions of the four threaded holes (13) respectively correspond to the positions of the four threaded grooves (4), and the corresponding threaded grooves (4) and threaded holes (13) are threadedly connected with bolts (15). The outer side of one end of the bolt (15) is threadedly connected with a nut (17), and the outer side of the nut (17) is threadedly connected with a threaded ring (19). A convex cap (20) is fixedly mounted on the top of the threaded ring (19), and the convex cap (20) is sleeved on the outer side of the end of the bolt (15).

2. A wind turbine blade root bolt protection device according to claim 1, characterized in that: The angle between two adjacent thread grooves (4) is forty-five degrees, the angle between two adjacent thread holes (13) is forty-five degrees, two thread grooves (30) are provided inside the assembly plate (3), the angle between the two thread grooves (30) is sixty degrees, and the two thread grooves (30) are symmetrically located on both sides of one of the thread grooves (4), two thread holes (31) are provided inside the assembly plate (21), the angle between the two thread holes (31) is sixty degrees, and the two thread holes (31) are symmetrically located on both sides of one of the thread holes (13), the two thread grooves (30) correspond to the positions of the two thread holes (31) respectively, and the corresponding thread grooves (30) and thread holes (31) are both threadedly connected with bolts (15).

3. A wind turbine blade root bolt protection device according to claim 2, characterized in that: A magnet ring 1 (18) is fixedly mounted on the bottom of the threaded ring (19); a movable ring groove 1 (22) is provided inside the assembly plate 2 (21); a magnet ring 2 (25) is slidably mounted inside the movable ring groove 1 (22); the magnet ring 2 (25) has the same magnetic pole as the magnet ring 1 (18) on the opposite side; a reinforcing plug rod (26) is fixedly mounted on the bottom of the magnet ring 2 (25); a circular slot (14) is provided inside the assembly plate 2 (21) on the side away from the blade (2); a circular plug hole (6) is provided on the side away from the hub (1) of the assembly plate 1 (3); the position of the circular plug hole (6) corresponds to the position of the circular slot (14); the position of the reinforcing plug rod (26) corresponds to the position of the circular plug hole (6) and the circular slot (14).

4. A wind turbine blade root bolt protection device according to claim 3, characterized in that: A sliding column (23) is fixedly installed inside the movable ring groove (22), and the magnet ring (25) is slidably installed on the outside of the sliding column (23).

5. A wind turbine blade root bolt protection device according to claim 4, characterized in that: A spring 1 (24) is fixedly mounted on the top of the magnet ring 2 (25); one end of the spring 1 (24) away from the magnet ring 2 (25) is fixedly connected to the top of the inner cavity of the movable ring groove 1 (22); and the spring 1 (24) is sleeved and mounted on the outer side of the sliding column (23).

6. A wind turbine blade root bolt protection device according to claim 5, characterized in that: A movable annular groove 2 (28) is provided inside the assembly plate 1 (3), a magnet ring 3 (27) is slidably installed inside the movable annular groove 2 (28), a spring 2 (29) is fixedly installed at the bottom of the magnet ring 3 (27), and one end of the spring 2 (29) away from the magnet ring 3 (27) is fixedly connected to the bottom of the inner cavity of the movable annular groove 2 (28).

7. A wind turbine blade root bolt protection device according to claim 6, characterized in that: The thread groove one (4) and the thread groove two (30) are both fixedly installed with a central plug post (5), and the bottom of the bolt (15) is provided with a central plug hole (16), and the position of the central plug hole (16) corresponds to the position of the central plug post (5).

8. A wind turbine blade root bolt protection device according to claim 7, characterized in that: The center plug hole (16) is provided with an annular groove inside, the center plug column (5) is provided with a movable circular groove (8), a movable iron block (7) is slidably mounted inside the movable circular groove (8), a connecting column (9) is fixedly mounted at the bottom of the movable iron block (7), four inclined blocks (10) are fixedly mounted at the bottom of the connecting column (9), inclined surfaces of the four inclined blocks (10) are all slidably mounted with inclined blocks (12), and one end of the inclined block (12) away from the inclined block (10) is fixedly mounted with a push-out block (11).

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