Rotor conductive screw, generator rotor and generator set

Abstract

The utility model discloses a rotor conductive screw, generator rotor and generator set. Rotor conductive screw is used for bearing the current of generator rotor and is transported to generator rotor winding, and the rotor conductive screw includes the electric pole body and the bottom insulating cylinder, the sealing ring, the lower insulating cylinder, the elastic element, the upper insulating cylinder and the compression nut that are successively installed on the conductive screw, and wherein, when the compression nut is tightened, the upper insulating cylinder, the elastic element, the lower insulating cylinder, the sealing ring and the bottom insulating cylinder are successively extruded, the sealing ring and the elastic element are deformed to compensate the looseness of the compression nut. The utility model can ensure that the sealing ring is always in the compression state, significantly improves the sealing reliability, and effectively prevents hydrogen leakage. Effectively solve the fundamental defect that only rigid thread anti-looseness can not cope with material creep and thermal expansion and contraction in prior art.

Description

Technical Field

[0001] This utility model relates to the field of generator accessories technology, and in particular to a rotor conductive screw, a generator rotor, and a generator set. Background Technology

[0002] Generators are crucial equipment in nuclear power plants; their failure can lead to generator shutdowns and significant losses. Existing generator rotors are equipped with conductive screws (internal and external conductive screws). These screws serve to carry the generator rotor current and deliver the rectified current from the exciter to the generator rotor windings. They also contribute to sealing the hydrogen inside the generator rotor chamber, preventing hydrogen leakage through the conductive screws.

[0003] During generator operation, the generator is filled with hydrogen. The generator rotor is sealed with sealing tiles to prevent hydrogen leakage, while the conductive screws are sealed by internal conductive screws, external conductive screws, and excitation end seals to prevent hydrogen leakage. Figure 1 In the existing conductive screw sealing structure design shown (the sealing structures of the inner and outer conductive screws are the same), the bottom end of the conductive screw is threadedly connected to the generator rotor. The conductive screw includes a pole body 1 and, from bottom to top, a bottom insulating cylinder 2, a lower sealing ring 31, an upper sealing ring 32, an upper insulating cylinder 6, a clamping nut 7, a lower nut 8, an insulating sleeve 9, and an upper nut 11, which are sequentially fitted on the outer periphery of the pole body 1. The clamping force from top to bottom starting from the upper nut 11 also enhances the stability of the threaded connection between the bottom end of the conductive screw and the generator rotor. The clamping nut 7, the lower nut 8, the insulating sleeve 9, and the upper nut 11 are used to fix the conductive screw and transmit centrifugal force to the generator rotor. The upper sealing ring 32 and the lower sealing ring 31 constitute a seal. An airtightness test hole is provided on the shaft of the conductive screw for conducting an airtightness test between the upper sealing ring 32 and the lower sealing ring 31 during assembly.

[0004] Specifically, Figure 1 In the existing sealing structure design of the conductive screw, the clamping nut 7 is tightened by torque. At this time, the clamping nut 7 compresses the upper sealing ring 32 and the lower sealing ring 31 downward through the upper insulating cylinder 6. The radial inner and outer sides of the upper sealing ring 32 and the lower sealing ring 31 expand under the force. The outer side of the upper sealing ring 32 and the lower sealing ring 31 squeezes and seals the inner side of the generator rotor (the blank area outside the upper sealing ring 32 and the lower sealing ring 31). The inner side of the upper sealing ring 32 and the lower sealing ring 31 squeezes and seals the outer peripheral surface of the conductive screw, thereby realizing the hydrogen sealing function (in fact, only the lower sealing ring 31 performs the sealing function). Then the clamping nut 7 is connected to the upper insulating cylinder 6 by a pin to lock and prevent loosening. After the uppermost nut 11 is tightened, the pressure is transmitted downward to the pole boss 12 to ensure that the conductive screw is reliably fixed and to prevent the conductive screw from radially displacing under centrifugal force.

[0005] However, the clamping nut 7 is difficult to prevent loosening. Although the clamping nut 7 and the upper insulating cylinder 6 are fixedly connected by a pin, this fixing method only achieves the function of stopping the clamping nut 7 and the upper insulating cylinder 6, and cannot prevent the clamping nut 7 and the upper insulating cylinder 6 as a whole from loosening between themselves and the conductive screw. Specifically, temperature fluctuations caused by changes in excitation current, or changes in centrifugal force generated by the start-up and shutdown of the generator set, may cause uneven deformation of the upper sealing ring 32 and the lower sealing ring 31. As a result, the clamping nut 7 and the upper insulating cylinder 6 may loosen due to insufficient preload, ultimately increasing the risk of hydrogen leakage.

[0006] In practical applications, generator rotors often leak from the conductive screws when cold after shutdown, but the seals return to normal when hot. Analysis revealed that during the airtightness test of the conductive screws in a cold rotor state, as centrifugal force and current heating disappear, the temperature of the upper sealing ring 32 and the lower sealing ring 31 decreases and they contract, resulting in a decrease in their clamping force and a reduction in sealing performance. This leads to gas leakage from the boundary between the upper sealing ring 32 and the lower sealing ring 31 during the airtightness test. In other words, hydrogen gas in the rotor chamber can easily enter the conductive screw from the boundary between the upper sealing ring 32 and the lower sealing ring 31, causing leakage, and can also easily pass through the boundary between the outer side of the upper sealing ring 32 and the lower sealing ring 31 and the inner side of the generator rotor, causing leakage. Utility Model Content

[0007] The purpose of this invention is to provide a rotor conductive screw, a generator rotor, and a generator set, aiming to solve the problem that the sealing structure on the existing conductive screw is prone to hydrogen leakage during generator set operation due to uneven deformation of the upper and lower sealing rings.

[0008] To solve the above-mentioned technical problems, the purpose of this utility model is achieved through the following technical solution: providing a rotor conductive screw for carrying the current of the generator rotor and transmitting it to the generator rotor winding; The conductive screw includes a pole body and a bottom insulating cylinder, a sealing ring, a lower insulating cylinder, an elastic element, an upper insulating cylinder, and a clamping nut, which are sequentially fitted onto the conductive screw. The rotor conductive screw is configured such that, when the clamping nut is tightened, it sequentially compresses the upper insulating cylinder, the elastic element, the lower insulating cylinder, the sealing ring, and the bottom insulating cylinder, causing the sealing ring and the elastic element to deform to compensate for the loosening of the clamping nut.

[0009] Furthermore, the sealing ring is made of a rubber material that is elastic and corrosion-resistant.

[0010] Furthermore, the sealing ring is one of the following: annular fluororubber, silicone rubber, or nitrile rubber.

[0011] Furthermore, the elastic element is a resilient structure with deformable memory characteristics.

[0012] Furthermore, the elastic element can be one of a disc spring, a helical spring, or a rubber spring.

[0013] Furthermore, the ends of the pole body are enclosed.

[0014] Furthermore, the rotor conductive screw also includes a lower nut, an insulating sleeve, an insulating pad, and an upper nut sequentially fitted onto the pole body; the side of the lower nut facing away from the insulating sleeve abuts against the clamping nut.

[0015] Furthermore, the bottom of the pole body is provided with a pole boss, which is threadedly connected to the generator rotor.

[0016] This utility model embodiment also provides a generator rotor, including the rotor conductive screw as described above.

[0017] This utility model embodiment also provides a generator set, including the generator rotor as described above.

[0018] The beneficial effects of this embodiment are as follows: When the clamping nut is tightened, it applies axial pressure, which is transmitted through the upper insulating cylinder to the elastic element and the lower insulating cylinder, and finally acts on the sealing ring and the bottom insulating cylinder. Under the action of axial pressure, the sealing ring undergoes radial expansion deformation, its inner surface tightly fitting against the outer surface of the pole body, and its outer surface forming an effective seal with the inner contact surface of the generator rotor, thereby blocking the hydrogen leakage path. At the same time, the elastic element undergoes compression deformation under pressure to store elastic potential energy; thus, when the clamping force of the sealing ring decreases due to temperature changes, material aging, or centrifugal force fluctuations, the elastic element releases potential energy through rebound, automatically compensating for the compression of the sealing ring and the loosening of the clamping nut, thereby maintaining continuous clamping force and preventing seal failure. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 A schematic diagram of the structure of a conductive screw provided by the prior art.

[0021] Figure 2 This is a schematic diagram of the structure of the conductive screw provided in an embodiment of the present invention.

[0022] Explanation of the markings in the image: 1. Conductive screw; 2. Bottom insulating cylinder; 3. Sealing ring; 31. Lower sealing ring; 32. Upper sealing ring; 4. Lower insulating cylinder; 5. Elastic element; 6. Upper insulating cylinder; 7. Compression nut; 8. Lower nut; 9. Insulating sleeve; 10. Insulating pad; 11. Upper nut; 12. Pole boss; 13. First test hole. Detailed Implementation

[0023] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0024] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0025] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the invention. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise.

[0026] It should also be further understood that the term "and / or" as used in this specification and the appended claims refers to any combination of one or more of the associated listed items and all possible combinations, and includes such combinations.

[0027] Please see Figure 2 This utility model provides a rotor conductive screw for carrying the current of the generator rotor and transmitting it to the generator rotor winding; The conductive screw includes a pole body 1 and a bottom insulating cylinder 2, a sealing ring 3, a lower insulating cylinder 4, an elastic element 5, an upper insulating cylinder 6, and a clamping nut 7, which are sequentially fitted onto the conductive screw. The rotor conductive screw is configured such that when the clamping nut 7 is tightened, it sequentially squeezes the upper insulating cylinder 6, the elastic element 5, the lower insulating cylinder 4, the sealing ring 3, and the bottom insulating cylinder 2, causing the sealing ring 3 and the elastic element 5 to deform in order to compensate for the loosening of the clamping nut 7.

[0028] In this embodiment, when the clamping nut 7 is tightened, it applies axial pressure, which is transmitted through the upper insulating cylinder 6 to the elastic element 5 and the lower insulating cylinder 4, and finally acts on the sealing ring 3 and the bottom insulating cylinder 2. Under the action of axial pressure, the sealing ring 3 undergoes radial expansion deformation, its inner side is tightly fitted with the outer surface of the pole body 1, and its outer side forms an effective seal with the inner contact surface of the generator rotor, thereby blocking the hydrogen leakage path. At the same time, the elastic element 5 undergoes compression deformation under pressure to store elastic potential energy; thus, when the clamping force of the sealing ring 3 decreases due to temperature changes, material aging, or centrifugal force fluctuations, the elastic element 5 releases potential energy through rebound, automatically compensating for the compression of the sealing ring 3 and compensating for the loosening of the clamping nut 7, thereby maintaining continuous clamping force and preventing seal failure.

[0029] Based on this, compared with the prior art, this embodiment replaces the upper sealing ring 32 and lower sealing ring 31 of the prior art with a single sealing ring 3 in the force transmission path between the sealing ring 3 and the clamping nut 7. Dynamic compensation is achieved by adding an elastic element 5. When changes in operating conditions cause the clamping force of the sealing ring 3 to decrease, the potential energy stored in the elastic element 5 is released, actively and continuously compensating for this decrease. This prevents the clamping nut 7 and the upper insulating cylinder 6 from loosening due to insufficient preload, and effectively maintains a stable clamping force on the sealing ring 3. This ensures that the sealing ring 3 is always in a compressed state, significantly improving sealing reliability and effectively preventing hydrogen leakage. It effectively solves the fundamental defect of the prior art, which relies solely on rigid threads for loosening prevention and cannot cope with material creep and thermal expansion and contraction.

[0030] In one embodiment, the sealing ring 3 is made of an elastic and corrosion-resistant rubber material.

[0031] In this embodiment, the sealing ring 3 is made of an elastic and corrosion-resistant rubber material, which can undergo elastic deformation under pressure to form a tight seal. The corrosion resistance ensures that the sealing ring 3 will not undergo chemical degradation or physical performance decline when exposed to hydrogen for extended periods, maintaining its sealing function and structural integrity.

[0032] In a specific embodiment of the sealing ring 3, the sealing ring 3 is one of annular fluororubber, silicone rubber or nitrile rubber.

[0033] In this specific embodiment, fluororubber exhibits excellent high-temperature and chemical resistance, making it suitable for high-temperature and high-pressure environments; silicone rubber possesses good elasticity and low-temperature resistance, making it suitable for wide-temperature operating conditions; and nitrile rubber excels in oil resistance and abrasion resistance, making it suitable for scenarios containing lubricants or contaminants. Selecting the appropriate material based on actual application requirements can optimize sealing performance and service life.

[0034] In a preferred embodiment, the sealing ring 3 is made of fluororubber.

[0035] In one embodiment, the elastic element 5 is a resilient structure with deformable memory characteristics.

[0036] In this embodiment, the elastic element 5 is a resilient structure with deformable memory properties. After being compressed by an external force, the elastic element 5 can recover its original shape due to the memory effect of its material. This characteristic allows the elastic element 5 to automatically apply a compensating force when the clamping force of the sealing ring 3 weakens due to temperature changes or creep, maintaining a constant pressure on the sealing ring 3 and preventing loosening.

[0037] In a specific embodiment of the elastic element 5, the elastic element 5 can be one of a butterfly spring, a helical spring, or a rubber spring.

[0038] In this specific embodiment, the disc spring has high load capacity and compact structure, making it suitable for space-constrained installation environments; the helical spring provides linear elastic response, facilitating precise control of clamping force; and the rubber spring combines elasticity and damping characteristics, capable of absorbing vibration and impact. Selecting the appropriate type of elastic element based on specific design requirements can achieve the optimal compensation effect.

[0039] In a preferred embodiment, the elastic element 5 is a butterfly spring.

[0040] In one embodiment, the end of the pole body 1 is closed.

[0041] First, it should be noted that, as Figure 1 In the prior art shown, the pole body 1 requires sealing performance of its upper and lower parts during factory shipment or maintenance. To this end, a first test hole 13 is provided on the outer side of the pole body 1. Gas is injected through the first test hole 13 to conduct an airtightness test on the upper and lower parts of the pole body 1. During normal sealing operations, the upper sealing ring 32 and the lower sealing ring 31 are fitted at and blocked by the first test hole 13. However, if the upper sealing ring 32 and the lower sealing ring 31 become loose due to uneven deformation, the boundary between the upper sealing ring 32 and the lower sealing ring 31 can easily leak through the first test hole 13. This allows hydrogen gas to enter the pole body 1 from the first test hole 13 and leak from the upper and lower ends. Therefore, the sealing performance at the boundary between the upper sealing ring 32 and the lower sealing ring 31 also needs to be tested. For this purpose, a second test hole is provided at the end (usually the upper end) of the pole body 1. Gas is injected through the second test hole to test the sealing performance of the boundary between the upper sealing ring 32 and the lower sealing ring 31. (See reference...) Figure 1 The dashed line in the diagram represents the path between the first test hole 13 and the second test hole.

[0042] In this embodiment, the upper sealing ring 32 and the lower sealing ring 31 are improved to a single sealing ring 3. After the elastic element 5 compensates for the clamping force on the sealing ring 3 (i.e., compensates for loosening), the single sealing ring 3 in this embodiment can stably seal the first test hole 13, ensuring that hydrogen gas will not enter the interior of the conductive rod from the first test hole 13. Thus, this embodiment eliminates the need for the second test hole in the prior art. That is, the end (i.e., the upper end) of the pole body 1 can be sealed, thereby eliminating potential leakage points.

[0043] In one embodiment, the rotor conductive screw further includes a lower nut 8, an insulating sleeve 9, an insulating pad 10, and an upper nut 11, which are sequentially fitted onto the pole body 1; the side of the lower nut 8 facing away from the insulating sleeve 9 abuts against the clamping nut 7.

[0044] In this embodiment, the side of the lower nut 8 facing away from the insulating sleeve 9 directly abuts against the clamping nut 7. By tightening the upper nut 11, pressure is transmitted to the lower nut 8 and the clamping nut 7 through the insulating pad 10 and the insulating sleeve 9, further enhancing the connection stability between the pole body 1 and the generator rotor. This structure can effectively resist centrifugal force and prevent radial displacement of the pole body 1. Compared with the existing... Figure 1 In contrast to existing technologies, this embodiment adds an insulating pad 10 between the upper nut 11 and the insulating sleeve 9, which can further improve the ability to withstand the centrifugal force of the conductive screw.

[0045] In one embodiment, the bottom of the pole body 1 is provided with a pole boss 12, which is threadedly connected to the generator rotor.

[0046] In this embodiment, a pole boss 12 is provided at the bottom of the pole body 1, which is directly connected to the generator rotor via threads. The pole boss 12 serves as a connection interface, providing not only a reliable mechanical fixing point but also ensuring smooth current conduction. The threaded connection facilitates installation and disassembly, while the boss structure enhances the strength and stability of the connection.

[0047] In this embodiment, after the upper nut 11 is tightened, the torque it generates will be transmitted downwards sequentially until it acts on the pole boss 12, thereby reliably fixing the conductive screw and preventing the conductive screw from undergoing radial displacement under centrifugal force.

[0048] This utility model embodiment also provides a generator rotor, including the rotor conductive screw as described above.

[0049] This utility model embodiment also provides a generator set, including the generator rotor as described above.

[0050] The above description is merely a specific embodiment of this utility model, but the protection scope of this utility model is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this utility model, and these modifications or substitutions should all be covered within the protection scope of this utility model. Therefore, the protection scope of this utility model should be determined by the scope of the claims.

Claims

1. A rotor conductive screw for carrying current in a generator rotor and transmitting it to the generator rotor windings, characterized in that: The conductive screw includes a pole body and a bottom insulating cylinder, a sealing ring, a lower insulating cylinder, an elastic element, an upper insulating cylinder, and a clamping nut, which are sequentially fitted onto the conductive screw. The rotor conductive screw is configured such that, when the clamping nut is tightened, it sequentially compresses the upper insulating cylinder, the elastic element, the lower insulating cylinder, the sealing ring, and the bottom insulating cylinder, causing the sealing ring and the elastic element to deform to compensate for the loosening of the clamping nut.

2. The rotor conductive screw according to claim 1, characterized in that, The sealing ring is made of elastic and corrosion-resistant rubber.

3. The rotor conductive screw according to claim 1, characterized in that, The sealing ring is one of the following: cyclic fluororubber, silicone rubber, or nitrile rubber.

4. The rotor conductive screw according to claim 1, characterized in that, The elastic element is a resilient structure with deformable memory characteristics.

5. The rotor conductive screw according to claim 1, characterized in that, The elastic element can be one of a disc spring, a helical spring, or a rubber spring.

6. The rotor conductive screw according to claim 1, characterized in that, The ends of the pole body are closed.

7. The rotor conductive screw according to claim 1, characterized in that, It also includes a lower nut, an insulating sleeve, an insulating pad, and an upper nut that are sequentially fitted onto the pole body; the side of the lower nut facing away from the insulating sleeve abuts against the clamping nut.

8. The rotor conductive screw according to claim 1, characterized in that, The bottom of the pole body is provided with a pole boss, which is threaded to the generator rotor.

9. A generator rotor, characterized in that, Including the rotor conductive screw as described in any one of claims 1 to 8.

10. A generator set, characterized in that, It includes the generator body and the generator rotor as described in claim 9.

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