Special tool for escaping and resetting rotor slot bottom filler strip of 1000MW generator set

Abstract

The utility model relates to the technical field of power generation, in particular to a tool special for escape reset of a rotor slot bottom filler strip of a 1000MW generator set. The tool comprises two insulating reset fixing pipes, two insulating push rods and a knocking module. The single sides of the two insulation reset fixing pipes are provided with groove lines used for containing the escape filler strips. The two insulating push rods are respectively arranged at the end parts in the two insulating reset fixing pipes; the insulating push rod is used for connecting a fixing clamp of the escape filler strip; the knocking module is fixedly connected with the ends, away from the escape filler strip, of the two insulating push rods. The device is simple in structure, the filler strip which is not stressed in the axial direction in a narrow space can be reset through a manual operation means, the operation method is simple, safe and effective, and a large amount of cost and time are saved. The risk that the insulation of the slot rotor is reduced is reduced, and the situation that the escape filler strips are possibly broken to damage fan blades or block ventilation during operation is avoided.

Description

Technical Field

[0001] This utility model relates to the field of power generation technology, and in particular to a special tool for resetting the escaped pad strip at the bottom of the rotor slot of a 1000MW generator set. Background Technology

[0002] The THDF125 / 67 generator is a 1000MW unit manufactured by Shanghai Generator Works using technology introduced from SIEMENS. It represents a domestic manufacturer with the technology and capability to produce single-shaft, full-speed 1000MW-class generators. The rotor diameter of this generator is... The rotor body is 6730mm long, and the total rotor length is 14800mm. The THDF 125 / 67 type 1000MW generator rotor adopts a loose slot wedge structure. During operation, due to the rotor force, the rotor coil is subjected to not only radial force but also axial force. The rotor coil and the wedge pads are in close contact with the bottom of the rotor slot wedge. When the rotor rotates, the centrifugal force causes a relatively loose structure at the bottom of the slot. In addition, due to the influence of coil mass distribution, temperature and other factors, the rotor coil and insulation run in close contact with the bottom of the rotor slot wedge. With the axial movement, if the pressure on the bottom pads is uneven or not firmly fixed, the bottom pads are prone to move in one direction due to the axial movement of the rotor coil. Furthermore, the rotor slot insulation of this type of generator is made of 1.4mm thick insulating material composed of glass fiber cloth and NOMEX fiber layer, which is relatively soft and can easily slide outward over the obstruction edge of the bottom coil protrusion. Therefore, the slot bottom pad can easily slip off the bottom of the rotor slot and move to one side. Over time, the moved slot bottom pad becomes longer and longer, and through the air guide tube, fan base, generator stator base, and cooler, it comes into contact with wear and wear or breaks, thus forming a sharp knife-shaped tip at the front end of the slot bottom pad that damages the insulation of the entire rotor slot winding. As shown in the appendix of this utility model... Figure 1 As shown.

[0003] The bottom insulation of the generator rotor slot is an important layer of insulation that isolates the bottom coil of the generator rotor from the metal at the bottom of the slot. If the bottom pad is damaged or slips out, it will inevitably affect the slot opening and bottom insulation of the generator rotor. As the situation develops, it will cause the generator rotor to be grounded at one point or multiple points.

[0004] Based on the 1000MW generators currently in operation, many units have experienced similar issues with slot bottom strip escape (such as Pinghai Unit 2 and Yuhuan Unit 4). The generator manufacturer's response is that to completely eliminate the slot bottom strip escape problem, the rotor needs to be returned to the factory, all coils removed, and the retaining blocks at the bottom coil slot openings replaced (or heightened) to prevent the slot bottom strips from exceeding the retaining blocks. The factory repair would take approximately one month, with total costs estimated at 9-10 million yuan.

[0005] To address this problem, this invention proposes a technical solution: by preparing a dedicated repositioning tool, the shim strip that is not subject to axial force in a confined space can be repositioned manually. The operation method is simple, safe, and effective, saving a significant amount of cost and time. Utility Model Content

[0006] To solve the above problems, this utility model discloses a special tool for resetting the escaped pad strips of the rotor slot bottom of a 1000MW generator set. The technical solution of this utility model is implemented as follows:

[0007] A special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set, including two insulated reset fixing tubes, two insulated push rods, and a striking module;

[0008] The two insulating reset fixing tubes have grooves on one side for accommodating the escape pad strip;

[0009] The two insulating push rods are respectively disposed at the ends of the two insulating reset fixing tubes;

[0010] The insulating push rod is used to connect the fixing clamp of the escape pad strip;

[0011] The striking module is fixedly connected to the end of the two insulating push rods away from the escape pad.

[0012] Preferably, it also includes a fixing clamp and an adjusting bracket;

[0013] The fixing clamp is disposed at one end of the adjusting bracket;

[0014] The fixing clamp is used to clamp the two insulating reset fixing tubes;

[0015] The adjusting bracket is at the same horizontal height as the two insulating reset fixing tubes.

[0016] Preferably, the insulating reset fixing tube is made of PPR.

[0017] Preferably, the insulating push rod is made of PPR.

[0018] Preferably, the insulating reset fixing tube is a D25PPR tube with a length of 2200mm.

[0019] Preferably, the insulating push rod is a PPR round tube with a diameter of 20mm and a length of 2300mm.

[0020] This invention successfully resets the escape pad by using a self-made special tool, reducing the risk of reduced insulation of the slot rotor and preventing the escape pad from breaking and damaging the fan blades or blocking ventilation during operation.

[0021] This specialized tool is designed and manufactured in-house, using common raw materials and is easy to make. It can be manually operated to reposition shims that are not under axial stress in confined spaces. The operation method is simple, safe and effective, saving a lot of money and time. Attached Figure Description

[0022] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0023] Identical parts are indicated by the same reference numerals. It should be noted that the terms "front," "rear," "left," "right," "up," and "down" used in the following description refer to directions in the accompanying drawings, while the terms "bottom surface," "top surface," "inner," and "outer" refer to directions toward or away from the geometric center of a specific part, respectively.

[0024] Figure 1 This is a diagram showing the layout of the rotor slots of a 1000MW generator set. The parts marked with circles in the diagram are the positions of the escape pads at the bottom of the generator set rotor windings.

[0025] Figure 2 This is a fault image of the generator rotor in an embodiment of this utility model;

[0026] Figure 3 This is a structural schematic diagram of an embodiment of the present utility model, wherein, Figure 3 The left image in the image is the front view. Figure 3 The right image in the image is a side view;

[0027] Figure 4 for Figure 3 The diagram shown is a structural diagram of the insulating reset fixing tube in the embodiment shown; wherein, Figure 4 The left image in the image is the front view; Figure 4 The right image in the image is a side view;

[0028] Figure 5 for Figure 3 The diagram shown in the embodiment illustrates the structure of the tapping module; wherein, Figure 5 The left image in the image is the front view. Figure 5 The right image in the image is a side view;

[0029] Figure 6 The recorded image is used for restoration in an embodiment of this utility model;

[0030] Figure 7 The image is a repaired record image according to an embodiment of this utility model.

[0031] The meanings of the symbols in the above figures are as follows:

[0032] 1. Escape pad strip;

[0033] 2. Insulating reset fixing tube;

[0034] 3. Insulated push rod;

[0035] 4. Tapping module;

[0036] 5. Fixing clips;

[0037] 6. Adjustable stand. Detailed Implementation

[0038] The technical solution of this utility model will be clearly and completely described below with reference to its embodiments. Obviously, the described embodiments are only some embodiments of this utility model, and not all embodiments. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of this utility model.

[0039] Unless otherwise defined, all technical and scientific terms used in this invention have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains; the terminology used in the detailed description is for the purpose of describing particular embodiments only and is not intended to limit the invention; the terms “comprising” and “having” and any variations thereof in the specification, claims and foregoing description of the invention are intended to cover non-exclusive inclusion.

[0040] In the description of the specific embodiments of this utility model, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this utility model, "multiple" means two or more, unless otherwise explicitly defined.

[0041] In this invention, the reference to "embodiment" means that a specific feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this invention. The appearance of this phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described in this invention can be combined with other embodiments.

[0042] In the description of this utility model embodiment, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone. Additionally, in this utility model, the character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0043] Throughout this invention, numerical values ​​represent approximate measurements or limits of a range to cover minute deviations from a given value, as well as embodiments with approximately the mentioned value and embodiments with the exact mentioned value. Except for the working examples provided at the end of the detailed description, all numerical values ​​of parameters (e.g., quantities or conditions) in this specification (including the appended claims) should be understood to be modified in all cases by the term “about,” regardless of whether “about” actually appears before the numerical value. “About” indicates that the stated numerical value allows for some minor inaccuracy (approaching the exact value in some way; approximately or reasonably approaching the value; almost). If the inaccuracy provided by “about” is not otherwise understood in this common sense in the art, then “about” as used in this invention at least indicates a variation that can be produced by common methods of measuring and using such parameters. For example, “about” may include a variation of less than or equal to 5%, optionally less than or equal to 4%, optionally less than or equal to 3%, optionally less than or equal to 2%, optionally less than or equal to 1%, optionally less than or equal to 0.5%, and in some respects, optionally less than or equal to 0.1%.

[0044] Additionally, the disclosure of the range includes the disclosure of all values ​​across the entire range and the disclosure of further subdivided ranges, including the endpoints and subranges given for these ranges.

[0045] Based on the 1000MW generators currently in operation, many units have experienced similar issues with slot bottom strip escape (such as Pinghai Unit 2 and Yuhuan Unit 4). The generator manufacturer's response is that to completely eliminate the slot bottom strip escape problem, the rotor needs to be returned to the factory, all coils removed, and the retaining blocks at the bottom coil slot openings replaced (or heightened) to prevent the slot bottom strips from exceeding the retaining blocks. The factory repair takes approximately one month, with total costs estimated at 9 million to 10 million yuan.

[0046] To address this problem, this invention proposes a technical solution: by preparing a dedicated repositioning tool, the shim strip that is not subject to axial force in a confined space can be repositioned manually. The operation method is simple, safe, and effective, saving a significant amount of cost and time.

[0047] The technical solution of this utility model will be further illustrated by specific embodiments below.

[0048] During the overhaul of the THDF 125 / 67 generator, after removing the rotor, it was discovered that the bottom pad of the second winding of the inner ring of the first pole of the generator rotor had shifted. The pad, which should have been inside the slot, was partially exposed. The displacement direction was from the excitation side to the steam side. The total length of the pad was 6730mm.

[0049] The power plant conducted a detailed survey of the spatial location where the bottom pads of the generator rotor slots had shifted. The survey results are as follows: Figure 2 As shown, the escape shim 1 is located on the steam side, in a confined and deep space, ruling out the possibility of manual repositioning. Given the 2m depth and limited space, an "extension arm" method was adopted to push the shim back to its original position. However, because the escape shim 1 is only 1.4mm thick and 1.19m long, it is extremely prone to bending and breaking, making it impossible for existing tools to evenly distribute force and move it inwards. Therefore, a special tool must be manufactured.

[0050] The special tools prepared in this embodiment are as follows: Figure 3-5 As shown.

[0051] The following is the preparation idea of ​​the special tool in this embodiment.

[0052] Specialized tools must ensure that the escape pad 1 remains straight under axial force to prevent bending, loss of load, and breakage. Material selection must consider the rotor winding ends; conductive metals cannot be used to avoid metal powder residue at the ends or damage to the windings and insulation. After comparing material hardness and suitable specifications, two 2200mm D25PPR tubes were selected as extension arms to fix the pad. Based on the escape pad 1's thickness of 1.4mm, a slot approximately 2mm wide and 1.5m long was cut on one side of each D25PPR tube. On-site operation then clamps the pad with the two slotted tubes, ensuring the escaped portion is strictly bound while allowing axial advancement of the escape pad 1, and preventing bending damage from external forces. This part is called the insulation reset fixing tube 2. Then, two... The circular tube, serving as the transmission part for pushing the escape pad 1 to reset, is called the insulating push rod 3. To ensure consistent and even force on the two insulating push rods 3, a fixing module is added to the end of each insulating push rod 3, and force is applied to the fixing module to push the insulating push rod 3; this part is called the striking module 4. To prevent uneven height and wobbling between the insulating reset fixing tube 2 and the insulating push rod 3 at the rotor end, which could damage the escape pad 1 at the slot, a fixing clamp 5 and an adjustable bracket 6 are added to the insulating reset fixing tube 2 to ensure axial alignment between the insulating reset fixing tube 2 and the escape pad 1. By repeatedly striking the striking module 4, the escape pad 1 is slowly pushed axially, successfully resetting it. The resetting process is as follows... Figure 6As shown in the image. After reset, the generator insulation measurement passed, the gaps were refilled with the gaskets, and the two ends of the slot were resealed, eliminating the potential for insulation degradation caused by ash and oil vapor ingress, ensuring safe equipment operation, and achieving the expected goals. The image after reset is shown in the image. Figure 7 As shown.

[0053] In this embodiment, with a thorough understanding of the equipment structure within the rotor slots, a self-made special tool for resetting the escape pad 1 of the rotor slot bottom pad of a 1000MW generator unit was used to successfully reset the escape pad 1. This prevents the escape pad 1 from potentially breaking and damaging the fan blades or blocking ventilation during operation, thus eliminating this defect. This operation method is simple, safe, and effective, saving a significant amount of time and money, and has high potential for widespread application.

[0054] It should be noted that the above description is only a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A special tool for resetting the escaped pad strip at the bottom of the rotor slot of a 1000MW generator set, characterized in that, It includes two insulated reset fixing tubes, two insulated push rods, and a striking module; The two insulating reset fixing tubes have grooves on one side for accommodating the escape pad strip; The two insulating push rods are respectively disposed at the ends of the two insulating reset fixing tubes; The insulating push rod is used to connect the fixing clamp of the escape pad strip; The striking module is fixedly connected to the end of the two insulating push rods away from the escape pad.

2. The special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set according to claim 1, characterized in that, It also includes fixing clamps and adjustment brackets; The fixing clamp is disposed at one end of the adjusting bracket; The fixing clamp is used to clamp the two insulating reset fixing tubes; The adjusting bracket is at the same horizontal height as the two insulating reset fixing tubes.

3. The special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set according to claim 1, characterized in that, The insulating reset fixing tube is made of PPR.

4. The special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set according to claim 1, characterized in that, The insulating push rod is made of PPR.

5. The special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set according to claim 1, characterized in that, The insulating reset fixing tube is a D25PPR tube with a length of 2200mm.

6. The special tool for resetting the escaped pad strip of the rotor slot bottom of a 1000MW generator set according to claim 1, characterized in that, The insulated push rod is a PPR round tube with a diameter of 20mm and a length of 2300mm.

Images