Generator rotor penetrating device based on push type method and operation method

Abstract

The invention relates to a generator rotor penetration device based on a push-type method and an operation method, which are suitable for a rotor installation process in generator overhaul. The device comprises linear I-shaped steel, a hanging belt, a 5-ton chain block, a tension meter, a sliding plate, a rubber plate and the like, and a rotor is stably pushed into a stator cavity through synchronous control and accurate tension monitoring. Compared with a traditional method, most operation can be completed only through one crane, dependence on the crane is reduced, and the risk of damage to the turbine bearing box foundation is reduced. In the operation process, accurate control is achieved through a chain block and a tension meter, shaking or deviation of the rotor in the propelling process is avoided, and operation safety and working efficiency are improved. The method can effectively solve the problems of limited construction period, high equipment damage risk and the like in a traditional method, and has a wide application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of generator motor maintenance, and in particular to a generator rotor penetration device and an operating method based on a propulsion method. Background Art

[0002] During the generator maintenance process of a power plant, the insertion of the generator rotor is a complex and high-risk task. The generator rotor is usually very heavy. For example, the weight of a 300MW-class generator rotor can reach 53 tons. Therefore, the insertion operation involves the lifting and moving of heavy objects, which places extremely high demands on load-bearing components and lifting tools. In addition, the insertion process of the generator rotor will directly affect the overall maintenance period of the generator and steam turbine, thus placing high demands on the accuracy and efficiency of the operation.

[0003] The traditional method of inserting the generator rotor generally uses two cranes to work together to lift the rotor and slowly push it into the stator cavity. In order to fix the rotor position, it is usually necessary to use a long steel wire rope to fix a fixed pulley at the junction of the medium and low pressure cylinders of the steam turbine, and use thick rubber to protect the part where the steel wire rope contacts the cylinder body. At the same time, the lower cylinder of the low pressure cylinder is covered with a tarpaulin to ensure that the cylinder body is not damaged. This method has the following major defects:

[0004] Risk of damage to the foundation structure: The traditional method requires the use of the high-pressure and low-pressure cylinder bearing boxes of the steam turbine as ground anchors, which is easy to damage the foundation of the bearing box. Such damage to the foundation structure will increase maintenance costs and bring inconvenience to future maintenance.

[0005] Crane resource occupation: Traditional rotor penetration operations require two cranes to work together. The high frequency of crane use not only increases the complexity of the penetration operation, but also easily affects other maintenance work of the steam turbine, thus leading to the problem of mutual constraints on the construction period. This phenomenon of mutual constraints on multiple processes will extend the entire maintenance cycle and reduce work efficiency.

[0006] Friction and stability issues: In the traditional method, the rotor is placed on a wooden bracket and a rubber plate, and fixed to the stator with a slide plate, and lubricating oil is applied between the slide plate and the bracket to reduce friction. However, this method is difficult to ensure uniform distribution of friction in actual operation, especially during the propulsion process, it is easy to shake and deviate, reducing the safety of operation.

[0007] Complex operation and high risk: The traditional rotor threading method involves many operating steps, high personnel cooperation requirements, and close attention to the equipment status to prevent accidents during the movement. The complex operation process increases the safety risk. Once the operation is wrong or the equipment fails, it may cause irreversible damage to the rotor or stator cavity.

[0008] In order to solve the above problems, the existing technology has begun to explore a simpler, safer and more efficient method for inserting the generator rotor. The ideal technical solution should reduce the dependence on the turbine bearing box foundation, optimize the use of the crane, simplify the operation process, thereby improving work efficiency and reducing safety risks.

[0009] The present invention is proposed in this context. Through the innovative propulsion-type rotor penetration device and method, the shortcomings of the prior art such as foundation damage risk, high vehicle resource occupation, and unstable operation are effectively solved, providing an efficient, safe and economical solution for the maintenance of generators. Summary of the invention

[0010] The present invention relates to a propulsion-type rotor penetration device and an operation method thereof for overhauling a generator in a power plant, and is particularly suitable for the rotor penetration process of a 300MW-class generator into a stator cavity. The conventional generator rotor penetration method generally requires the use of two cranes to hoist the rotor from the outside into the stator cavity and fix it by using a wire rope and a fixed pulley at the junction of the medium and low pressure cylinders. This method has the following defects during operation:

[0011] The turbine's bearing box needs to be used as a ground anchor, which may cause damage to the bearing box foundation.

[0012] Two cranes are required to work together, which not only increases the frequency of crane use, but also affects the normal progress of other processes.

[0013] There are mutual constraints between the processes, which inevitably affects the overhaul period of steam turbines and generators.

[0014] Due to the large friction between the slide plate and the bracket in the traditional method, the rotor propulsion process may not be smooth enough, posing certain safety hazards.

[0015] The present invention provides an improved push-type rotor penetration device and method to solve the above-mentioned problems and improve the safety and working efficiency of the rotor penetration process.

[0016] Technical Solution

[0017] The push-type rotor-piercing device of the present invention mainly includes the following components and process steps:

[0018] Processed beam and electric hoist: The device uses a processed beam and two electric hoists to lift and advance the rotor to a specified position aligned with the center of the stator cavity through synchronous control. This solution no longer relies on the turbine's bearing box as a ground anchor, avoiding the risk of damage to the bearing box foundation.

[0019] I-beam: I-beam is fixed to the end of the rotor and serves as a support structure for rotor hoisting and propulsion. The combination of I-beam and sling ensures that the rotor is stably aligned with the center of the stator cavity.

[0020] 5-ton fall chain and tension meter: Two 5-ton fall chains are installed on the lifting ears on both sides of the generator stator, and a tension meter is set in the fall chain to monitor and accurately control the tension on both sides during the rotor propulsion process in real time. The fall chain is manually operated to keep the tension on both sides consistent, thereby ensuring that the rotor is smoothly advanced along the direction of the stator cavity to avoid unnecessary deviation or shaking.

[0021] Slide plate and rubber plate: A special slide plate is installed at the bottom of the rotor, and lubricating oil is applied between the slide plate and the rubber plate to reduce friction during propulsion. This design effectively improves the propulsion efficiency of the rotor and ensures that the rotor enters the stator cavity smoothly.

[0022] Optimized crane usage: During the entire rotor insertion process, only one crane is needed to perform most of the lifting operations, and the second crane is only used for auxiliary work in the final stage for about fifteen minutes. By optimizing the frequency of crane usage, the interference with the turbine's professional crane is significantly reduced.

[0023] Procedure

[0024] The push-type rotor penetration method of the present invention comprises the following specific operation steps:

[0025] Use crane No. 1 to lift the I-beam and install it on the rotor end.

[0026] Hang the sling on crane No. 1 and lift the rotor so that its center position is aligned with the center of the stator cavity.

[0027] Install a support plate or large bench and place the rotor end on the support.

[0028] Lower the sling in the center of the rotor and adjust the sling to a single-strand U-shape to stably suspend the rotor shaft neck to prevent the rotor from shifting.

[0029] Hang two 5-ton fall chains on the lifting ears on both sides of the generator stator, connect the other end to the I-beam at the end of the rotor, and tighten the fall chains.

[0030] Manually pull the fall chain to ensure that the fall chains on both sides are synchronized. The tension meter monitors the tension in real time to ensure that the force is even during the advancement process. At the same time, the No. 1 crane supports the shaft diameter of the rotor and slowly pushes the rotor into the stator cavity.

[0031] When the rotor reaches the specified position, place its end on a small bench, fix the rotor and loosen the U-shaped sling to complete the rotor threading operation.

[0032] Restore the lower cover of the generator housing and install the fake tile to support the rotor. After that, use the No. 1 crane to remove the I-beam and install the pull plate to further support and fix the rotor.

[0033] Beneficial Effects

[0034] By improving the structural design of the crossbeam and the fall chain, it is no longer necessary to use the turbine bearing box as a ground anchor, thereby avoiding damage to the foundation structure and extending the service life of the equipment. This method only requires one crane to operate, and the use time of the second crane is limited to the final auxiliary stage, which reduces the frequency of crane use and improves the control of the main line construction period. The fall chain is equipped with a tension meter to monitor the tension in real time to ensure the stability and consistency of the rotor during the propulsion process, reducing safety risks. Due to the optimization of crane use and simplification of process flow during operation, the rotor penetration operation time is significantly shortened, providing a guarantee for the synchronous maintenance of generators and turbines. This propulsion-type rotor penetration scheme is suitable for generators of different specifications, especially the maintenance of large generators, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] 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.

[0036] Figure 1 The figure is a schematic diagram of the operation flow of an embodiment of the present invention. DETAILED DESCRIPTION

[0037] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. At the same time, it is explained here that in order to make the embodiments more detailed, the following embodiments are the best and preferred embodiments, and those skilled in the art may also adopt other alternatives to implement some known technologies; and the accompanying drawings are only for more specific description of the embodiments, and are not intended to specifically limit the present invention.

[0038] It should be noted that the references to "one embodiment", "an embodiment", "an exemplary embodiment", "some embodiments" and the like in the specification indicate that the embodiments described may include specific features, structures or characteristics, but not every embodiment may include the specific features, structures or characteristics. In addition, when a specific feature, structure or characteristic is described in conjunction with an embodiment, it should be within the knowledge of a person skilled in the art to implement such feature, structure or characteristic in conjunction with other embodiments (whether or not explicitly described).

[0039] In general, a term can be understood, at least in part, from its use in context. For example, depending, at least in part, on the context, the term "one or more" as used herein can be used to describe any feature, structure, or characteristic in the singular sense, or can be used to describe a combination of features, structures, or characteristics in the plural sense. Additionally, the term "based on" can be understood as not necessarily intended to convey an exclusive set of factors, but can instead, depending, at least in part, on the context, allow for the presence of other factors that are not necessarily explicitly described.

[0040] like Figure 1 Shown DETAILED DESCRIPTION

[0042] 1. Device composition

[0043] I-beam: used to be installed at the end of the rotor to cooperate with the subsequent lifting and pushing operations. Its material must have sufficient strength and load-bearing capacity to ensure that it will not be deformed or damaged during the lifting and pushing of the rotor. For example, high-strength alloy steel can be selected, with a yield strength of not less than [X]MPa and a tensile strength of not less than [Y]MPa to ensure that it can withstand the weight of the rotor and various forces during operation.

[0044] Slings: including slings for lifting the center of the rotor and single-strand U-shaped slings for holding the rotor shaft neck. The slings should be made of high-strength, low-elongation synthetic fiber materials, such as polyester fiber or aramid fiber, to ensure that they will not break or over-elongate during the lifting process. Its safe working load should not be less than [specific multiples] of the rotor weight. For example, for a 53-ton rotor, the sling's safe working load can be set to no less than 60 tons, and the width and thickness of the sling should be designed according to the actual stress conditions to ensure uniform stress distribution and avoid local wear or damage.

[0045] 5-ton fall chain: There are two of them, which are hung on the lifting ears on both sides of the generator stator and the I-beam bolting holes at the end of the rotor. The chain of the fall chain should be made of high-strength alloy steel with good wear resistance and fatigue resistance. The internal structure of the fall chain should ensure its smooth operation and have a reliable braking device to prevent the chain from accidentally slipping during the pulling process. At the same time, the fall chain should be equipped with an accurate tension gauge, and the measurement accuracy of the tension gauge should reach ± ​​[specific accuracy value], for example, ± 0.1 tons, so that the operator can accurately control the tension on both sides to ensure that the rotor remains balanced and stable during the propulsion process.

[0046] Large bench and small bench: The large bench is used to temporarily support the rotor end during operation, and the small bench is used to cushion the rotor after it is in place. The bench can be made of high-quality wood, such as oak or beech, and its structure should be stable and able to bear the weight of the rotor without deformation or damage. The height and size of the bench should be designed according to the specific structure and operation requirements of the generator. For example, the height of the large bench can be designed to [specific height value] to facilitate the placement and operation of the rotor; the height of the small bench should match the support position of the rotor end to ensure that the rotor is in a stable state after placement.

[0047] Dummy pad: used to cushion the rotor in specific operation steps. The material of the dummy pad should have good wear resistance and lubricity, such as babbitt alloy or copper alloy. The size and shape of the dummy pad should accurately match the mating parts of the rotor and related components to ensure that the rotor can be effectively supported after installation and reduce friction and wear between the rotor and other components.

[0048] Pull plate: Installed to the end of the rotor during operation, the material and structure of the pull plate should be able to withstand a certain amount of tension, and the connection with the rotor end should be firm and reliable. Its design should take into account the convenience of installation and disassembly, for example, bolt connection or ferrule connection can be used to ensure that it will not loosen or fall off during operation.

[0049] 2. Operation process

[0050] Preparation

[0051] Conduct a comprehensive inspection of all the components used, including whether the I-beam has any defects such as deformation and cracks, whether the sling has any wear and tear, whether the 5-ton chain is smooth, whether the tension gauge works normally, whether the structure of the large and small benches is stable, whether the surface of the false tile and the pull plate is smooth, whether the size matches, etc. Ensure that all components are in good working condition, and replace or repair them in time if there are any problems.

[0052] Install a 5-ton fall chain on the lifting ears on both sides of the generator stator, and check whether the hook of the fall chain is firm and whether the chain can be pulled freely and smoothly.

[0053] Place the I-beam in a position convenient for No. 1 crane to lift it, and clear the surrounding obstacles to ensure a safe and smooth lifting process.

[0054] Lift the rotor end and install the I-beam

[0055] Operate crane No. 1 to slowly lift the I-beam and accurately install it on the end of the rotor. During the installation process, ensure that the connection between the I-beam and the end of the rotor is firm and reliable. Bolt fastening or welding (according to actual design requirements) can be used to prevent the I-beam from falling off during subsequent operations.

[0056] After installation, check again the connection between the I-beam and the rotor, and whether the connection between the crane's hook and the I-beam is firm.

[0057] Lift the rotor center and adjust the position

[0058] Use crane No. 1 to hang the sling and adjust the sling to the appropriate length to ensure that it can stably hold the center of the rotor.

[0059] Slowly start the crane and lift the rotor. During the lifting process, closely observe the rotor's posture to ensure that it remains horizontal. Move the rotor to the same center position as the stator bore by adjusting the crane's lifting height and lateral movement. At this point, a laser rangefinder or other positioning equipment can be used to accurately measure the center deviation between the rotor and the stator bore. The deviation should be controlled within ±[specific deviation value], for example, ±5mm.

[0060] Place the bench and adjust the straps

[0061] Arrange operators to lift the large bench to a suitable position under the rotor end and ensure that the bench is placed stably.

[0062] Slowly lower the rotor center strap so that the rotor end gently falls on the large bench. During the lowering process, keep the rotor balanced to prevent it from shaking or shifting.

[0063] Change the lowered sling into a single strand, suspend the rotor shaft neck in a U shape, and gradually tighten the sling to make the sling evenly stressed, ensuring that the rotor is firmly supported at the shaft neck.

[0064] Connect the fall chain and tighten it

[0065] Hang the other ends of the two 5-ton fall chains on the bolting holes of the I-beam at the end of the rotor, and make sure the hooks are secure.

[0066] The operator manually pulls the fall chains on both sides at the same time, gradually tightening the fall chains to generate a certain pre-tension. During the tightening process, by observing the value of the tension gauge, ensure that the tension on both sides is basically consistent, and the deviation does not exceed ± [specific tension deviation value], for example, ± 0.5 tons.

[0067] Push the rotor into the chamber

[0068] Operators on both sides keep the consistency of manually pulling the fall chain, slowly and steadily pull the fall chain, so that the rotor is gradually pushed into the stator bore with the No. 1 crane holding the shaft diameter. During the pushing process, the relative position of the rotor and the stator bore is constantly observed to ensure that the rotor can accurately penetrate the stator bore.

[0069] Continue to push the rotor until it is in place. At this point, use a laser rangefinder or other measuring tools again to check whether the position of the rotor in the stator bore meets the design requirements. For example, the axial position deviation of the rotor should be controlled within ±[specific axial deviation value], and the radial position deviation should be controlled within ±[specific radial deviation value].

[0070] Install the small bench and complete the rotor threading operation

[0071] Install a small bench on the end of the rotor and place it in a suitable position so that it can firmly support the rotor.

[0072] Loosen the U-shaped slings so that the rotor is fully supported by the small bench. When loosening the slings, do it slowly to prevent the rotor from shifting.

[0073] At this point, the rotor threading operation is completed and a final check is made on the entire device and the position of the rotor to ensure that everything is normal.

[0074] Subsequent Operations

[0075] Pull the lower cover back to its original position, and use the No. 1 crane to install the dummy tile to the designated position to cushion the rotor. The installation of the dummy tile should ensure that it fits tightly with the rotor surface to provide good support and lubrication.

[0076] Use crane No. 1 to lift the I-beam and remove it from the end of the rotor. Pay attention to safety during the removal process to prevent the I-beam from falling and injuring people.

[0077] Finally, install the pull plate to the end of the rotor and place a small bench at the appropriate position to prepare for subsequent generator assembly or commissioning work.

[0078] 3. Operation precautions

[0079] During the entire operation process, all operators must strictly abide by safety operating procedures and wear personal protective equipment, such as safety helmets, safety shoes, gloves, etc.

[0080] Crane operations should be performed by personnel who have received professional training and obtained the corresponding qualification certificates. Before operation, the crane must be fully inspected, including the brake system, hooks, wire ropes and other components, to ensure safe and reliable operation of the crane.

[0081] When lifting and pushing the rotor, keep the movements slow and steady, avoid sudden stops, sudden starts or violent shaking, and prevent the rotor from colliding with other parts.

[0082] Pay close attention to the value on the tension gauge of the 5-ton fall chain to ensure that the tension on both sides is balanced. If the tension deviation is found to be too large, stop the operation immediately and continue to move forward after adjustment.

[0083] When placing and using large and small stools, make sure they are stable and will not move or tilt.

[0084] When installing and disassembling I-beams, false tiles, pull plates and other components, use appropriate tools and follow the correct procedures to prevent component damage or personal injury.

[0085] Obvious warning signs should be set up at the operation site to prohibit irrelevant personnel from entering the operation area to ensure a safe operating environment. The present invention covers any substitution, modification, equivalent method and scheme made on the essence and scope of the present invention. In order to enable the public to have a thorough understanding of the present invention, specific details are described in detail in the following preferred embodiments of the present invention, and those skilled in the art can fully understand the present invention without the description of these details. In addition, in order to avoid unnecessary confusion about the essence of the present invention, well-known methods, processes, processes, components and circuits are not described in detail.

[0086] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A generator rotor penetration device based on a push-type method, characterized in that: include: I-beam, used to fix the rotor end so that the rotor can enter the stator cavity; Lifting straps, used to lift the rotor and keep its center position aligned with the stator cavity; Two 5-ton fall chains, each with a tension gauge, are hung on the lifting ears on both sides of the generator stator, and the other end is connected to the I-beam at the end of the rotor, which is used to accurately control the propulsion force of the rotor by manual pulling; Customized skid plates and rubber plates are set at the bottom of the rotor to reduce friction during propulsion.

2. The generator rotor penetration device according to claim 1, characterized in that: The device only needs to use one crane during the rotor penetration process, and uses a second crane for about fifteen minutes in the final stage to reduce the impact on other equipment.

3. The generator rotor penetration device according to claim 1 or 2, characterized in that: The fall chain and the tension gauge can ensure smooth advancement of the rotor during penetration, avoid using the bearing box between the high-pressure and low-pressure cylinders as a ground anchor, and reduce the risk of foundation damage.

4. A generator rotor penetration operation method based on a push-type method, characterized in that: The following steps are involved: (1) Use crane No. 1 to lift the I-beam and install it on the rotor end; (2) Use a sling to lift the rotor to a position aligned with the center of the stator cavity; (3) Lift and place the support plate to fix the rotor end position; (4) Adjust the sling to a single strand and hang it in a U shape on the rotor shaft neck, tighten and secure it; (5) Hang two 5-ton fall chains on the lifting ears on both sides of the generator stator, connect the other end to the I-beam hole at the end of the rotor, and tighten the fall chains; (6) The chains on both sides are manually pulled synchronously, and the force gauge is used for monitoring. Crane No. 1 cooperates with the supporting shaft diameter to slowly push the rotor into the stator cavity; (7) After the rotor is in place, install the support plate to cushion the rotor and release the U-shaped sling.

5. The operating method according to claim 4, characterized in that: After the rotor is pushed forward, the lower cover is restored to its original position and the false tiles are installed to support the rotor. Then the No. 1 crane is used to remove the I-beam, and finally the pull plate is installed and supported again.

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