CN116780835A - Process method for replacing single stator coil of end grouting adhesive generator - Google Patents
Process method for replacing single stator coil of end grouting adhesive generator Download PDFInfo
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- CN116780835A CN116780835A CN202311035489.1A CN202311035489A CN116780835A CN 116780835 A CN116780835 A CN 116780835A CN 202311035489 A CN202311035489 A CN 202311035489A CN 116780835 A CN116780835 A CN 116780835A
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- stator coil
- stator
- damaged
- glue
- end part
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- 238000000034 method Methods 0.000 title claims abstract description 48
- 239000000853 adhesive Substances 0.000 title claims description 4
- 230000001070 adhesive effect Effects 0.000 title claims description 4
- 239000003292 glue Substances 0.000 claims abstract description 76
- 238000004382 potting Methods 0.000 claims description 16
- 238000005498 polishing Methods 0.000 claims description 13
- 238000004140 cleaning Methods 0.000 claims description 3
- 238000002347 injection Methods 0.000 claims description 3
- 239000007924 injection Substances 0.000 claims description 3
- 230000007547 defect Effects 0.000 abstract 1
- 229940125904 compound 1 Drugs 0.000 description 12
- 150000001875 compounds Chemical group 0.000 description 3
- 230000001066 destructive effect Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000008439 repair process Effects 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
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- Manufacture Of Motors, Generators (AREA)
Abstract
The invention relates to the field of generators and discloses a process method for replacing a single stator coil by an end glue pouring structure generator, which overcomes the defect that the glue pouring structure of the end part of a stator is firm and integrated, destructively disassembles a main insulating layer of the end part of the damaged stator coil, disassembles covered strands one by one, disassembles glue pouring on two side surfaces of the end part of the damaged stator coil, polishes the glue pouring on the bottom surface of the end part of the damaged stator coil, ensures that the space can meet the assembly of a new stator coil, assembles the new coil, and finally performs glue pouring on the partial space of the end part of the stator.
Description
Technical Field
The invention relates to a technique for repairing a generator stator, in particular to a process method for replacing a single stator coil of an end glue pouring structure generator.
Background
The novel structure of the end part of the stator of the generator ensures that the stator coil of the end part is integrated through a glue pouring process, and the structure is firm and reliable, and is not easy to cause a plurality of problems such as loose and abrasion of the end part.
However, when the generator is operated on site, the stator is often failed due to various reasons, the damaged stator coil needs to be replaced when the stator is sometimes processed, and most of the cases are that a single damaged stator coil is replaced.
Disclosure of Invention
The invention aims to provide a practical and feasible process method for replacing a single stator coil of a generator stator with a glue filling structure at the end part of ensuring quality, which is realized by the following steps:
s1, removing parts in a stator bore related to the damaged stator coil and parts at the end part of the stator, wherein the removed parts comprise a slot wedge, parts at the position of a nose end, parts at the position of a slot outlet and cover plates on the inner surface of the end part of the stator, and pouring glue around the damaged stator coil is exposed;
s2, removing pouring glue on the inner surface of the stator end part related to the damaged stator coil, wherein the removing method comprises the steps of marking out a contour line of the damaged stator coil to be removed on the inner surface of the pouring glue in an involute area of the stator end part, and removing the pouring glue on the inner surface of the damaged stator coil by using tools such as a flat shovel, a hand hammer and the like according to the contour line;
s3, cutting off the damaged stator coil, wherein the cutting-off position is the junction position of the nose end position and the involute area of the damaged stator coil, and the section of the strand is exposed;
s4, removing the strand wires of the damaged stator coil in the glue pouring area and the residual main insulating layer wrapping the strand wires, wherein the removing steps are as follows:
s41, cutting two gaps on a main insulating layer of the involute area at the end part of the stator, which damages the inner surface of the stator coil, tearing off the main insulating layer between the two gaps, and exposing stranded wires of the damaged stator coil;
s42, pulling out the strands one by one from a slit cut in the inner surface of the involute region of the damaged stator coil from which the top surface main insulating layer is removed, pulling out the strands from the nose end position to the notch position, and cutting the strands at the notch position;
s43, after all the strands in the end part pouring glue area of the damaged stator coil are pulled out, removing the main insulating layer of the end part remained in the pouring glue;
s5, removing the side pouring glue related to damaging the stator coil, polishing the bottom pouring glue, and removing and polishing the side pouring glue:
s51, dismantling side pouring glue by using a flat shovel and a hand hammer, wherein the operation cannot damage the main insulating layers of adjacent stator coils on two sides;
s52, polishing the pouring glue on the bottom surface of the damaged stator coil, wherein the polishing depth is standard to ensure that the pouring glue can flow when a new coil is assembled, and the operation cannot damage the main insulating layers of other stator coils on the two side surfaces and the bottom surface;
s6, removing the straight line section in the stator bore of the damaged stator coil, wherein the removing method comprises the steps of removing the straight line section of the damaged stator coil from the lower line slot in the stator bore by using tools such as a hand-pulling block, a rubber hammer and the like;
s7, assembling a new stator coil, wherein the assembling steps are as follows:
s71, comprehensively cleaning the inside of a stator bore and the end part of a stator;
s72, assembling a new stator coil and temporarily fixing the new stator coil;
s73, assembling a slot wedge in a stator bore, assembling a stator coil nose end position part, assembling a stator coil notch outlet position part and the like, and permanently fixing a new stator coil;
s8, local glue filling is carried out on the end part of the stator, and the glue filling step is as follows:
s81, assembling an inner surface cover plate, wherein the lowest position of a stator end pouring glue area related to a new stator coil is provided with the inner surface cover plate of a temporary process hole, and the highest position is provided with the inner surface cover plate of the temporary process hole;
s82, pouring glue into the end part of the new stator coil from the process hole at the lowest position, and exhausting outwards from the process hole at the highest position;
s83, stopping the glue injection operation after the filling glue is filled;
s84, curing the pouring glue;
s85, replacing the inner surface cover plate with the process holes with the inner surface cover plate without the process holes.
The beneficial effects of the invention are that
1. The invention provides a process method for replacing a single stator coil of a glue-filled stator on site, which considers the technical difficulty that the single stator coil is locally removed after the end part of the stator is integrated by glue filling, avoids destructive removal of all stator coils, realizes the replacement of the single stator coil on site, and minimizes the on-site repair workload and loss;
2. the invention fully considers the actual situation of the field, establishes the process method of locally disassembling the pouring glue on the field, destructively disassembling a single damaged stator coil, reassembles a new stator coil and re-locally pouring glue, and meets the popularization and application requirements of the generator with the new structure of pouring glue at the end part of the stator.
Drawings
Fig. 1 is a schematic side view of a stator end of a glue-pouring structure.
Fig. 2 is a schematic diagram of the stator coil.
Fig. 3 is a sectional view showing an internal structure of the stator coil.
Fig. 4 is a cross-sectional view of a new stator coil after replacement.
The label specification in the drawings: 1-pouring glue; 2-stator coils; 3-damaging the stator coil; 4-new stator coils; 5-a main insulating layer; 6-strands; 7-stator ends; 8-involute area; 9-nose position; 10-notch outlet position; 11-within the stator bore; 12-slot wedge; 13-inner surface cover plate.
Detailed Description
The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings, and it is obvious that the described embodiments are only some embodiments of the present invention, but not all embodiments, and all embodiments obtained by those skilled in the art without making any inventive effort are within the scope of the present invention based on the embodiments of the present invention.
As shown in fig. 1 to 4, the general idea of the process method for replacing a single stator coil of an end potting compound structure generator is that, since the potting compound 1 covers all stator coils 2 of a stator end 7 and fuses the damaged stator coils 3 with adjacent intact stator coils 2, the damaged stator coils 3 are all removed in the whole repair process and other stator coils 2 must not be damaged, and simultaneously the potting compound 1 around the damaged stator coils 3 is removed to provide enough operation space and flow space for local potting compound for assembling a new stator coil 4, the inner surface of a main insulating layer 5 in the potting compound 1 in an involute area 8 of the damaged stator coils 3 is damaged and cut, strands 6 of the damaged stator coils 3 are pulled out one by one, after the residual main insulating layer 5 is cleaned, space is created for removing the potting compound 1, and space is created for local potting compound flow for the adjacent stator coils 2.
The specific process implementation process is as follows:
s1, removing parts of a stator bore 11 and parts of a stator end 7 related to the damaged stator coil 3, wherein the removed parts comprise a slot wedge 12, parts of a nose end position 9, parts of a slot outlet position 10 and inner surface cover plates 13 of the stator end 7, and the pouring glue 1 around the damaged stator coil 3 is exposed;
since the stator coil 2 is fixed by a plurality of parts, including the stator bore 11 part and the stator end 7 part, the parts are all removed before the potting compound 1 is removed.
S2, removing the pouring glue 1 on the inner surface of the stator end part 7 related to the damaged stator coil 3, wherein the removing method is that the contour line of the damaged stator coil 3 to be removed is drawn on the inner surface of the pouring glue 1 in the involute area 8 of the stator end part 7, and the pouring glue 1 on the inner surface of the damaged stator coil 3 is removed by using tools such as a flat shovel, a hand hammer and the like according to the contour line;
since the end of the damaged stator coil 3 is covered with the potting compound 1, in order not to damage other adjacent stator coils 2, the potting compound 1 on the inner surface of the damaged stator coil 3 needs to be precisely removed by position after scribing, so that the inner surface of the damaged stator coil 3 can be seen.
S3, cutting off the damaged stator coil 3, wherein the cutting-off position is the junction position of the nose end position 9 and the involute region 8 of the damaged stator coil 3, and exposing the section of the strand 6;
since the damaged stator coil 3 cannot be directly taken out of the potting compound 1, the method of destructive disassembly is adopted, and the stator coil can be destructively disassembled after being cut off, so that the stator coil is conveniently cut off at the nose end position 9 for the next operation.
S4, removing the strands 6 of the damaged stator coil 3 in the pouring glue 1 area and the residual main insulating layer 5 wrapping the strands 6, wherein the removing steps are as follows:
s41, cutting two gaps on the main insulating layer 5 of the involute area 8 of the stator end 7, which damages the inner surface of the stator coil 3, tearing off the main insulating layer 5 between the two gaps, and exposing the stranded wires 6 of the damaged stator coil 3;
s42, pulling out the strands 6 one by one from gaps cut in the inner surface of the involute region 8 of the damaged stator coil 3 with the top surface main insulating layer 5 removed, pulling out the strands from the nose end position 9 to the notch position 10, and cutting the strands at the notch position 10;
s43, after all the strands 6 in the region of the end part pouring glue 1 of the damaged stator coil 3 are pulled out, removing the main insulating layer 5 of which the end part remains in the pouring glue 1;
since the main insulation 5 of the damaged stator coil 3 is relatively thick, the strands 6 must be exposed after the main insulation 5 exposed from the inner surface of the stator end 7 is cut and half-removed, so that the strands 6 can be pulled out one by one, and operated from the nose position 9 to the notch position 10.
S5, removing the side pouring glue 1 related to the damaged stator coil 3, polishing the bottom pouring glue 1, and removing and polishing the side pouring glue 1, wherein the steps are as follows:
s51, removing the side pouring glue 1 by using a flat shovel and a hand hammer, wherein the operation cannot damage the main insulating layers 5 of the adjacent stator coils 2 on the two sides;
s52, polishing the pouring glue 1 which damages the bottom surface of the stator coil 3, wherein the polishing depth is in order that the pouring glue 1 can flow when a new coil is assembled, and the operation cannot damage the main insulating layers 5 of other stator coils 2 on the two side surfaces and the bottom surface;
because the strands 6 and the main insulating layer 5 in the region of the pouring glue 1 at the end part of the damaged stator coil 3 are completely removed, the pouring glue 1 at the two sides of the damaged stator coil 3 is removed in space, the pouring glue 1 is hit into the space left after the damaged stator coil 3 is removed by using a flat shovel and a hand hammer, and the pouring glue 1 at the bottom is cleaned by matching with a polishing tool.
S6, removing the straight line section in the stator bore 11 of the damaged stator coil 3, wherein the removing method comprises the steps of removing the straight line section of the damaged stator coil 3 from the lower line groove in the stator bore 11 by using tools such as a hand-pulling block, a rubber hammer and the like;
since the damaged stator coil 3 needs to be completely removed, the straight line segment in the stator bore 11 is also removed.
S7, assembling a new stator coil 4, wherein the assembling steps are as follows:
s71, comprehensively cleaning the stator bore 11 and the stator end 7;
s72, assembling a new stator coil 4 and temporarily fixing the new stator coil;
s73, assembling a slot wedge 12 in a stator bore 11, assembling a part at the nose end position 9 of a stator coil 2, assembling a part at the notch position 10 of the stator coil 2 and the like, and permanently fixing a new stator coil 4;
since the potting compound 1 on both sides of the damaged stator coil 3 has been cleaned, the new stator coil 4 is placed into the end portion in the normal manner when assembled, and the assembly of the portion 11 in the stator bore is the same as before.
S8, local glue filling is carried out on the end part 7 of the stator, and the glue filling step is as follows:
s81, assembling an inner surface cover plate 13, wherein the lowest position of the region of the stator end 7 of the new stator coil 4, which is filled with the glue 1, is provided with the inner surface cover plate 13 of the temporary process hole, and the highest position is provided with the inner surface cover plate 13 of the temporary process hole;
s82, pouring glue 1 into the end part of the new stator coil 4 from the process hole at the lowest position, and exhausting outwards from the process hole at the highest position;
s83, stopping the glue injection operation after the pouring glue 1 is filled;
s84, curing the pouring adhesive 1;
s85, replacing the inner surface cover plate 13 with the process holes with the inner surface cover plate 13 without the process holes.
Since the stator end 7 only removes the potting compound 1 involved in damaging the stator coil 3, the potting compound 1 needs to be partially filled during the reloading, the potting compound 1 needs to be injected at the lowest position during the operation, and the highest position is exhausted.
Finally, the protective scope of the invention is not limited to the embodiments described above. It will be apparent to those skilled in the art that various modifications and variations can be made to the present invention without departing from the scope or spirit of the invention. The present invention is intended to include such modifications and alterations insofar as they come within the scope of the appended claims or the equivalents thereof.
Claims (1)
1. A process method for replacing a single stator coil of an end potting structure generator is characterized by comprising the following steps of: the method is realized through the following steps:
s1, removing parts in a stator bore (11) and parts at a stator end (7) related to a damaged stator coil (3), wherein the removed parts comprise a slot wedge (12), parts at a nose end position (9), parts at a slot outlet position (10) and cover plates (13) on the inner surface of the stator end (7), and exposing pouring glue (1) around the damaged stator coil (3);
s2, removing the pouring glue (1) on the inner surface of the stator end part (7) related to the damaged stator coil (3), wherein the removing method is to scratch the contour line of the damaged stator coil (3) to be removed on the inner surface of the pouring glue (1) in the involute area (8) of the stator end part (7), and remove the pouring glue (1) on the inner surface of the damaged stator coil (3) by using tools such as a flat shovel, a hand hammer and the like according to the contour line;
s3, cutting off the damaged stator coil (3), wherein the cutting-off position is the junction position of the nose end position (9) and the involute region (8) of the damaged stator coil (3), and the section of the strand (6) is exposed;
s4, removing the strands (6) of the damaged stator coil (3) in the pouring glue (1) area and the residual main insulating layer (5) wrapping the strands (6), wherein the removing steps are as follows:
s41, cutting two gaps on a main insulating layer (5) of the inner surface of the damaged stator coil (3) in an involute region (8) of the stator end part (7), and tearing off the main insulating layer (5) between the two gaps to expose a stranded wire (6) of the damaged stator coil (3);
s42, pulling out the strands (6) one by one from gaps cut in the inner surface of the involute region (8) of the damaged stator coil (3) with the top surface main insulating layer (5) removed, pulling out the strands from the nose end position (9) to the notch outlet position (10), and cutting the strands at the notch outlet position (10);
s43, after all the strands (6) in the region of the end part pouring glue (1) of the damaged stator coil (3) are pulled out, removing the main insulating layer (5) of which the end part is remained in the pouring glue (1);
s5, removing the side pouring glue (1) related to the damaged stator coil (3), polishing the bottom pouring glue (1), and removing and polishing the side pouring glue:
s51, dismantling the side pouring glue (1) by using a flat shovel and a hand hammer, wherein the operation cannot damage the main insulating layers (5) of the adjacent stator coils (2) on the two sides;
s52, polishing the pouring glue (1) which damages the bottom surface of the stator coil (3), wherein the polishing depth is in order that the pouring glue (1) can flow when a new coil is assembled, and the operation cannot damage the main insulating layers (5) of other stator coils (2) on the two side surfaces and the bottom surface;
s6, removing the straight line section in the stator bore (11) of the damaged stator coil (3), wherein the removing method comprises the steps of removing the straight line section of the damaged stator coil (3) from the lower line groove in the stator bore (11) by using tools such as a hand-pulling hoist, a rubber hammer and the like;
s7, assembling a new stator coil (4), wherein the assembling steps are as follows:
s71, comprehensively cleaning the stator bore (11) and the stator end part (7);
s72, assembling a new stator coil (4) and temporarily fixing the new stator coil;
s73, permanently fixing a new stator coil (4) by assembling slot wedges (12) in a stator bore (11), assembling parts of a nose end position (9) of the stator coil (2), assembling parts of a notch outlet position (10) of the stator coil (2) and the like;
s8, local glue filling of the end part (7) of the stator, wherein the glue filling step comprises the following steps:
s81, assembling an inner surface cover plate (13), wherein the lowest position of a stator end part (7) pouring glue (1) area related to a new stator coil (4) is provided with the inner surface cover plate (13) of a temporary process hole, and the highest position is provided with the inner surface cover plate (13) of the temporary process hole;
s82, pouring glue (1) into the end part of the new stator coil (4) from the process hole at the lowest position, and exhausting outwards from the process hole at the highest position;
s83, stopping the glue injection operation after the glue (1) is filled;
s84, curing the pouring adhesive (1);
s85, replacing the inner surface cover plate (13) with the process holes with the inner surface cover plate (13) without the process holes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311035489.1A CN116780835B (en) | 2023-08-17 | 2023-08-17 | Process method for replacing single stator coil of end grouting adhesive generator |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311035489.1A CN116780835B (en) | 2023-08-17 | 2023-08-17 | Process method for replacing single stator coil of end grouting adhesive generator |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN116780835A true CN116780835A (en) | 2023-09-19 |
| CN116780835B CN116780835B (en) | 2023-10-20 |
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|---|---|---|---|
| CN202311035489.1A Active CN116780835B (en) | 2023-08-17 | 2023-08-17 | Process method for replacing single stator coil of end grouting adhesive generator |
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Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0819200A (en) * | 1994-06-29 | 1996-01-19 | Toshiba Corp | Stator coil for rotating electric machine and its replacement method |
| CN101882844A (en) * | 2010-06-30 | 2010-11-10 | 上海电气电站设备有限公司 | Stator coil end encapsulating and fixing method |
| JP2015002624A (en) * | 2013-06-17 | 2015-01-05 | 三菱電機株式会社 | Replacement method of stator coil |
| CN109586519A (en) * | 2017-09-29 | 2019-04-05 | 上海宝钢工业技术服务有限公司 | The fast repairing method of variable-frequency high-voltage motor winding insulation breakage |
| CN113922601A (en) * | 2021-11-11 | 2022-01-11 | 哈尔滨电机厂有限责任公司 | Local replacement process method for upper-layer wire rod of stator of large-scale gas turbine generator |
| JP2022184299A (en) * | 2021-06-01 | 2022-12-13 | 三菱重工業株式会社 | Repair method for stator core |
-
2023
- 2023-08-17 CN CN202311035489.1A patent/CN116780835B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0819200A (en) * | 1994-06-29 | 1996-01-19 | Toshiba Corp | Stator coil for rotating electric machine and its replacement method |
| CN101882844A (en) * | 2010-06-30 | 2010-11-10 | 上海电气电站设备有限公司 | Stator coil end encapsulating and fixing method |
| JP2015002624A (en) * | 2013-06-17 | 2015-01-05 | 三菱電機株式会社 | Replacement method of stator coil |
| CN109586519A (en) * | 2017-09-29 | 2019-04-05 | 上海宝钢工业技术服务有限公司 | The fast repairing method of variable-frequency high-voltage motor winding insulation breakage |
| JP2022184299A (en) * | 2021-06-01 | 2022-12-13 | 三菱重工業株式会社 | Repair method for stator core |
| CN113922601A (en) * | 2021-11-11 | 2022-01-11 | 哈尔滨电机厂有限责任公司 | Local replacement process method for upper-layer wire rod of stator of large-scale gas turbine generator |
Non-Patent Citations (2)
| Title |
|---|
| 姜海东;: "600MW发电机定子槽楔松动造成线圈温度异常的分析", 华东电力, no. 11, pages 2442 - 2445 * |
| 廖义勇;: "600MW汽轮发电机定子绕组更换线棒绝缘监督", 华中电力, no. 05, pages 48 - 50 * |
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| CN116780835B (en) | 2023-10-20 |
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