CN112061967A - On-site installation method of hydro-generator rotor bracket - Google Patents
On-site installation method of hydro-generator rotor bracket Download PDFInfo
- Publication number
- CN112061967A CN112061967A CN202010937882.XA CN202010937882A CN112061967A CN 112061967 A CN112061967 A CN 112061967A CN 202010937882 A CN202010937882 A CN 202010937882A CN 112061967 A CN112061967 A CN 112061967A
- Authority
- CN
- China
- Prior art keywords
- main shaft
- rotor support
- generator
- rotor
- lifting appliance
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000009434 installation Methods 0.000 title claims abstract description 33
- 238000000034 method Methods 0.000 title claims abstract description 24
- 241000239290 Araneae Species 0.000 abstract 1
- 230000008569 process Effects 0.000 description 6
- 238000011065 in-situ storage Methods 0.000 description 2
- 238000003825 pressing Methods 0.000 description 2
- 230000009471 action Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000005484 gravity Effects 0.000 description 1
- 238000011900 installation process Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000001681 protective effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 239000000725 suspension Substances 0.000 description 1
- 230000007306 turnover Effects 0.000 description 1
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C1/00—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles
- B66C1/10—Load-engaging elements or devices attached to lifting or lowering gear of cranes or adapted for connection therewith for transmitting lifting forces to articles or groups of articles by mechanical means
- B66C1/22—Rigid members, e.g. L-shaped members, with parts engaging the under surface of the loads; Crane hooks
- B66C1/34—Crane hooks
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B66—HOISTING; LIFTING; HAULING
- B66C—CRANES; LOAD-ENGAGING ELEMENTS OR DEVICES FOR CRANES, CAPSTANS, WINCHES, OR TACKLES
- B66C13/00—Other constructional features or details
- B66C13/04—Auxiliary devices for controlling movements of suspended loads, or preventing cable slack
- B66C13/08—Auxiliary devices for controlling movements of suspended loads, or preventing cable slack for depositing loads in desired attitudes or positions
-
- H—ELECTRICITY
- H02—GENERATION; CONVERSION OR DISTRIBUTION OF ELECTRIC POWER
- H02K—DYNAMO-ELECTRIC MACHINES
- H02K15/00—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines
- H02K15/02—Methods or apparatus specially adapted for manufacturing, assembling, maintaining or repairing of dynamo-electric machines of stator or rotor bodies
Landscapes
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Manufacturing & Machinery (AREA)
- Power Engineering (AREA)
- Manufacture Of Motors, Generators (AREA)
Abstract
The invention belongs to the technical field of mounting methods of hydraulic generators, and particularly relates to a field mounting method of a hydraulic generator rotor bracket, which comprises the following steps: 1) fixedly supporting the assembled rotor support, moving the main shaft and inserting the main shaft into the rotor support for connection; 2) hoisting two ends of the main shaft by using crane equipment and turning over the main shaft in the air to adjust the main shaft to a state to be connected; 3) and hoisting the rotor support and the main shaft to the mounting position and mounting the main shaft. This scheme has been solved among the prior art and has received the restriction in space height to use under the two dolly bridge crane structural environment of two roof beams, the installation operation difficulty and the higher problem of cost of spider.
Description
Technical Field
The invention belongs to the technical field of mounting methods of hydraulic generators, and particularly relates to a field mounting method of a hydraulic generator rotor support.
Background
The rotor support of the medium-large hydraulic generator has the characteristics of large size and heavy weight, and is limited by the transportation condition of a power station, and the assembly of the rotor support can only adopt a field assembly mode. The rotor support needs to be sleeved on a main shaft when being installed, the operation in the prior art is generally that the main shaft is installed on a lower rack in a generator pit, then the assembled rotor support is turned over for 180 degrees in situ (the self position of the rotor support is determined by the structural characteristics of the rotor support to be just opposite to that of the rotor support during the assembling and the installation), and then the rotor support is hoisted to be right above the main shaft and is moved downwards to be installed on the main shaft, so that the installation operation of the rotor support is completed.
When the rotor support is turned in situ, the rotor support is deformed and damaged due to overlarge local stress caused by local contact with the ground and concentrated suspension points, and a disposable protection tool needs to be arranged aiming at a weak position, so that the turning operation cost of the rotor support is high. The travelling crane of the large and medium hydropower station is of a double-beam double-trolley bridge crane structure, and the travelling crane and the lifting balance beam of the double-trolley structure cannot rotate, so that the rotor support is difficult to adjust after being hoisted, and a positioning key for ensuring the alignment accuracy is arranged between the rotor support and the main shaft, so that the operation of the rotor support is difficult during installation; meanwhile, due to the limitation of the space height in the power station, when the single trolley is adopted for hoisting, the intersection point of the lifting rope is positioned in the installation space of the main shaft, so that the connection between the main shaft and the rotor support can be blocked, and the rotor support is difficult to be smoothly installed on the main shaft by adopting the single trolley for hoisting. Therefore, a field installation method of a generator rotor support which is limited in space height, uses a double-beam double-trolley bridge crane structure and is low in cost is urgently needed.
Disclosure of Invention
The invention aims to provide a field installation method of a hydraulic generator rotor bracket, which is limited in space height, in an environment of using a double-beam double-trolley bridge crane structure and is low in cost.
In order to achieve the above object, a basic aspect of the present invention provides a field installation method of a hydro-generator rotor bracket, including the steps of: 1) fixedly supporting the assembled rotor support, hoisting the main shaft by utilizing a lifting hook of a crane and vertically inserting the main shaft into the rotor support for connection; 2) connecting the front end of the main shaft with another lifting hook of the crane, and controlling the crane to enable the main shaft to turn over in the air and adjust the main shaft to a state that the main shaft is to be connected; 3) and after the main shaft is turned over, the connection between the rear end of the main shaft and the crane is disassembled, and the rotor support and the main shaft are hoisted to the installation position to install the main shaft.
The beneficial effect of this basic scheme lies in: the main shaft is moved and inserted into the rotor support to realize the connection operation between the main shaft and the rotor support, so that the problem that the rotor support is difficult to connect with the main shaft due to the space height limitation of an installation site when the rotor support is hoisted is avoided; through the combination of the step 1 and the step 2, the rotor support can be turned over in the air while the spindle is turned over in the air, and the rotor support cannot be locally stressed and concentrated when turned over in the air, so that a disposable protection tool is not required to be arranged, and compared with the prior art, the cost required by the turning over of the rotor support is reduced.
Further, in the step 1, the rotor support is fixedly supported in the generator pit. By adopting the arrangement mode, the characteristic that the space height at the generator pit of the installation site is larger can be fully utilized, so that the connection operation between the rotor support and the main shaft is convenient.
Further, in the step 1, the lower generator frame in the generator pit is used for supporting the rotor support. By adopting the arrangement mode, the rotor support is supported by the generator set structure installed on the installation site, and an independent supporting structure is not required to be additionally arranged to support the rotor support, so that the manufacturing and the use of installation auxiliary tools are reduced, and the reduction of the installation cost of the rotor support is facilitated.
Further, in step 1, the device used for moving the main shaft is a crane. The crane is the existing equipment in the installation field, so that additional independent hoisting equipment is not needed, and the equipment cost in the whole installation process is favorably reduced.
Further, step 2, still include the step of connecting the front end hoist at the front end of main shaft, shelve the front end hoist on the support on the terrace, lift the main shaft and insert in the front end hoist, make the front end hoist suit on the main shaft to set up the snap ring with the joint of main shaft in the front end hoist keep away from one side of rotor support. The front end of the main shaft refers to one end of the main shaft which needs to penetrate through the rotor support when the main shaft is connected with the rotor support. The front end lifting appliance is supported by the support, so that a certain space is formed between the front end lifting appliance and the floor, and when the main shaft is inserted into the front end lifting appliance, the space becomes a safety space between the main shaft and the floor, so that the main shaft is prevented from being in direct contact with the floor; meanwhile, the front end lifting appliance is connected with the main shaft in a sleeved mode, so that the main shaft cannot generate large pressure on the front end lifting appliance when inserted into the front end lifting appliance, the gravity of the main shaft is prevented from being transmitted to the floor through the front end lifting appliance and the support, and the floor is prevented from being damaged due to large concentration force; the mode that the main shaft is inserted into the front end lifting appliance can reduce the movement of the front end lifting appliance, and because the size and the mass of the front end lifting appliance are large, the working strength of field operators can be reduced by reducing the movement of the front end lifting appliance, so that the connection operation between the front end lifting appliance and the main shaft is facilitated.
Drawings
FIG. 1 is a schematic view showing the operation process of step 1 in an embodiment of the method for on-site installation of a rotor frame of a hydraulic generator according to the present invention;
FIG. 2 is a schematic diagram of the operation of step 2 in the embodiment of the present invention;
fig. 3 is a schematic view of the process of turning the main shaft in fig. 2.
Detailed Description
The following is further detailed by way of specific embodiments:
reference numerals in the drawings of the specification include: the device comprises a travelling crane track 1, a lifting hook 2, a mounting room terrace 3, a main shaft 4, a rear end lifting appliance 41, a rear end 42 of the main shaft, a front end 43 of the main shaft, a front end lifting appliance 44, a generator layer terrace 5, a generator pit 6, a rotor support 7, a lower frame 8 and a lifting rope 9.
Example (b): the method for installing the rotor support of the hydraulic generator on site comprises the steps that a double-beam double-small-axle type crane is arranged on the site where a hydropower station is installed, and the maximum hoisting weight of a small vehicle is larger than the sum of the weight of the rotor support 7 and the weight of a main shaft 4; a generator pit 6 which is sunken downwards is arranged in the field installation room, and a generator layer terrace 5 is arranged between the generator pit 6 and the installation room terrace 3; the space height between the travelling track 1 of the crane and the terrace 3 of the installation room can only be used for moving when the main shaft 4 is vertically hoisted; the field installation method of the rotor bracket specifically comprises the following steps:
1) hoisting the assembled rotor support 7 from a floor 3 of an installation room into a generator pit 6 by using a lifting hook 2 of a trolley of a crane, as shown in fig. 1 (an arrow in the figure indicates a motion path when a main shaft 4 is hoisted), installing a support for supporting the rotor support 7 on a lower frame 8 of a generator which is installed in the generator pit 6, placing the rotor support 7 on the support, leveling the rotor support 7 by padding a wedge plate between the support and the rotor support 7, arranging a pressing plate on the rotor support 7, and temporarily fixing the rotor support 7 by connecting the pressing plate and the lower frame 8 through a screw rod; the main shaft 4 is placed on the terrace 3 of the installation room when being transported to the installation room, the rear end 42 of the main shaft is connected with a rear end hanger 41, and the rear end 42 of the main shaft refers to one end of the main shaft 4 which cannot penetrate through the rotor support 7 in the process of being inserted into the rotor support 7; the rear end 42 of the main shaft is provided with a flange structure, and the rear end lifting appliance 41 is also provided with a corresponding flange structure, so that the rear end lifting appliance 41 and the rear end 42 of the main shaft can be conveniently connected through bolts; then, connecting the rear end lifting appliance 41 with a lifting hook 2 of a crane, and controlling the crane to vertically lift the main shaft 4 and move the main shaft from the installation room to a position right above a rotor support 7 in a generator pit 6; the rotor support 7 and the main shaft 4 are in interference fit, connection operation is carried out in a shrink fit mode, then after the hub part of the rotor support 7 is heated to meet the conditions required by shrink fit, the crane is controlled to enable the main shaft 4 to move downwards and be inserted into the rotor support 7, after the rotor support 7 is cooled, connection operation between the main shaft 4 and the rotor support 7 is achieved, and the temporary fixing structure of the rotor support 7 is removed.
2) Placing a front end lifting appliance 44 used for being connected with a front end 43 of a main shaft on a generator layer terrace 5, as shown in fig. 2 (an arrow in the figure indicates a movement path when the main shaft 4 and a rotor support 7 are lifted together), and arranging a support between the front end lifting appliance 44 and the generator layer terrace 5, so that a certain space is formed between the front end lifting appliance 44 and the generator layer terrace 5 under the action of the support, wherein the front end 43 of the main shaft refers to one end, which needs to penetrate through the rotor support 7, of the main shaft 4 in the process of inserting the rotor support 7, and the connection mode of the front end lifting appliance 44 and the main shaft 4 is in a sleeve joint mode; a main shaft 4 and a rotor support 7 are lifted from a generator pit 6 by a lifting hook 2 of a trolley of a crane through a lifting rope 9 and are moved to the position right above a front end lifting appliance 44, then the crane is controlled to enable the front end 43 of the main shaft to be inserted into the front end lifting appliance 44, finally a clamping ring is clamped on one side, away from the rotor support 7, of the front end 43 of the main shaft, which is located on the front end lifting appliance 44, and the front end lifting appliance 44 can be prevented from being separated from the main shaft 4 through the clamping ring; as shown in fig. 3 (an arrow in the figure indicates a turning process of the main shaft 4), the front end lifting appliance 44 is connected with the lifting hook 2 of another trolley of the crane through the lifting rope 9, the lifting ropes 9 connected with the two ends of the main shaft 4 all need to meet the length required by turning of the main shaft 4, then the crane is controlled to enable the lifting hooks 2 of the two trolleys to move to enable the main shaft 4 to turn 180 degrees in the air, so that 180-degree turning of the rotor support 7 is realized, and at the moment, the main shaft 4 is in a state to be connected; in the process of overturning the main shaft 4, a protective material is required to be arranged at the position where the rotor support 7 may contact with the lifting rope 9 for protection, so that the phenomenon that the rotor support 7 and the lifting rope 9 are damaged mutually is avoided.
3) And controlling the crane to hoist the rotor support 7 and the main shaft 4 to the installation position of the generator pit 6 and install the main shaft 4, and completing the installation operation of the rotor support 7 after the main shaft 4 is installed.
The foregoing is merely an example of the present invention and common general knowledge of known specific structures and features of the embodiments is not described herein in any greater detail. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be determined by the contents of the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (5)
1. The field installation method of the hydraulic generator rotor bracket is characterized in that: the method comprises the following steps: 1) fixedly supporting the assembled rotor support, moving the main shaft and inserting the main shaft into the rotor support for connection; 2) hoisting two ends of the main shaft by using crane equipment and turning over the main shaft in the air to adjust the main shaft to a state to be connected; 3) and hoisting the rotor support and the main shaft to the mounting position and mounting the main shaft.
2. The field installation method of a hydro-generator rotor bracket according to claim 1, characterized in that: in the step 1, the rotor support is fixedly supported in a generator pit.
3. The field installation method of a hydro-generator rotor bracket according to claim 2, characterized in that: in the step 1, the lower generator frame in the generator pit is used for supporting the rotor support.
4. The field installation method of a hydro-generator rotor bracket according to claim 1, characterized in that: in the step 1, the equipment used for moving the main shaft is a crane.
5. The field installation method of a hydro-generator rotor bracket according to claim 1, characterized in that: and 2, connecting the front end lifting appliance to the front end of the main shaft, placing the front end lifting appliance on a support on the floor, lifting the main shaft to insert into the front end lifting appliance, sleeving the front end lifting appliance on the main shaft, and arranging a clamping ring clamped with the main shaft on one side of the front end lifting appliance, which is far away from the rotor support.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010937882.XA CN112061967A (en) | 2020-09-09 | 2020-09-09 | On-site installation method of hydro-generator rotor bracket |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010937882.XA CN112061967A (en) | 2020-09-09 | 2020-09-09 | On-site installation method of hydro-generator rotor bracket |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN112061967A true CN112061967A (en) | 2020-12-11 |
Family
ID=73662806
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010937882.XA Pending CN112061967A (en) | 2020-09-09 | 2020-09-09 | On-site installation method of hydro-generator rotor bracket |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN112061967A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114221499A (en) * | 2021-11-11 | 2022-03-22 | 中船重工电机科技股份有限公司 | Method for separating rotor and main shaft of through-shaft permanent magnet motor in diesel engine main shaft jacking test |
Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1559748A (en) * | 2004-03-09 | 2005-01-05 | 沪东重机股份有限公司 | Large equipment mainshaft and rotor shrinking fit method |
| CN203474239U (en) * | 2013-09-26 | 2014-03-12 | 福建南电股份有限公司 | Generator rotor lifting appliance |
| US20160327016A1 (en) * | 2015-05-07 | 2016-11-10 | General Electric Company | Up-tower suspension system for a wind turbine rotor blade |
| CN205932956U (en) * | 2016-08-03 | 2017-02-08 | 无锡法拉第电机有限公司 | Generator rotor hoists frock |
| CN108448833A (en) * | 2018-03-14 | 2018-08-24 | 中国水利水电第五工程局有限公司 | A kind of generator amature and big axis connecting shaft method |
| CN208835946U (en) * | 2018-08-25 | 2019-05-07 | 中船重工电机科技股份有限公司 | A kind of permanent magnet coupling motor vertical assembling fixture |
| CN209396756U (en) * | 2018-12-26 | 2019-09-17 | 新乡市起重设备厂有限责任公司 | A kind of equalizer bar suspender |
| CN210693734U (en) * | 2019-08-01 | 2020-06-05 | 国网浙江省电力有限公司紧水滩水力发电厂 | Vertical hydraulic generator rotor hoisting auxiliary device based on laser positioning |
| CN111620239A (en) * | 2020-07-02 | 2020-09-04 | 贵州乌江水电开发有限责任公司东风发电厂 | Mirror plate overturning tool |
-
2020
- 2020-09-09 CN CN202010937882.XA patent/CN112061967A/en active Pending
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1559748A (en) * | 2004-03-09 | 2005-01-05 | 沪东重机股份有限公司 | Large equipment mainshaft and rotor shrinking fit method |
| CN203474239U (en) * | 2013-09-26 | 2014-03-12 | 福建南电股份有限公司 | Generator rotor lifting appliance |
| US20160327016A1 (en) * | 2015-05-07 | 2016-11-10 | General Electric Company | Up-tower suspension system for a wind turbine rotor blade |
| CN205932956U (en) * | 2016-08-03 | 2017-02-08 | 无锡法拉第电机有限公司 | Generator rotor hoists frock |
| CN108448833A (en) * | 2018-03-14 | 2018-08-24 | 中国水利水电第五工程局有限公司 | A kind of generator amature and big axis connecting shaft method |
| CN208835946U (en) * | 2018-08-25 | 2019-05-07 | 中船重工电机科技股份有限公司 | A kind of permanent magnet coupling motor vertical assembling fixture |
| CN209396756U (en) * | 2018-12-26 | 2019-09-17 | 新乡市起重设备厂有限责任公司 | A kind of equalizer bar suspender |
| CN210693734U (en) * | 2019-08-01 | 2020-06-05 | 国网浙江省电力有限公司紧水滩水力发电厂 | Vertical hydraulic generator rotor hoisting auxiliary device based on laser positioning |
| CN111620239A (en) * | 2020-07-02 | 2020-09-04 | 贵州乌江水电开发有限责任公司东风发电厂 | Mirror plate overturning tool |
Non-Patent Citations (6)
| Title |
|---|
| 姜明忠等: "桃源水电站机组大件吊装技术与场地布置", 《桃源水电站机组大件吊装技术与场地布置》 * |
| 姜明忠等: "桃源水电站机组大件吊装技术与场地布置", 《桃源水电站机组大件吊装技术与场地布置》, no. 3, 14 January 2016 (2016-01-14), pages 67 - 71 * |
| 彭兵等: "《发电机转子轮毂倒立烧嵌施工技术》", 《施工技术》, no. 15, pages 112 - 113 * |
| 编委会: "《机电设备安装》", vol. 1, 31 December 2017, 中国环境出版社, pages: 110 - 113 * |
| 陈秀芝, 中国电力出版社 * |
| 魏亚垒等: "去学水电站转子中心体现场热套新工法浅析", 《装备维修技术》, vol. 1, pages 63 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114221499A (en) * | 2021-11-11 | 2022-03-22 | 中船重工电机科技股份有限公司 | Method for separating rotor and main shaft of through-shaft permanent magnet motor in diesel engine main shaft jacking test |
| CN114221499B (en) * | 2021-11-11 | 2023-09-01 | 中船重工电机科技股份有限公司 | Method for separating rotor and main shaft of permanent magnet motor penetrating through shaft in diesel engine main shaft jacking test |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US8469209B2 (en) | Removal apparatus for a torque converter and a starting motor from an auxiliary compartment on a gas turbine | |
| CN101284628B (en) | Hoisting method for framework of large tonnage pressing machine | |
| JP4896784B2 (en) | Wind turbine tower nacelle mounting method and apparatus | |
| CN101114786A (en) | Hanging method using C-beam piercing core hanging large-scale electric motor and C-beam structure | |
| CN202358849U (en) | Small-size suspension crane | |
| CN205772984U (en) | A kind of hanging apparatus of monolithic steel truss | |
| JP2011079634A (en) | Hoisting device of heat exchanger | |
| CN112061967A (en) | On-site installation method of hydro-generator rotor bracket | |
| CN201553565U (en) | Low-temperature tower crane | |
| CN101450766B (en) | Lifting installation method for ultralong workpiece and used fixture cross beam | |
| CN210340141U (en) | House building engineering lifting device | |
| CN109244946A (en) | A kind of electric integrated apparatus for examination and repair | |
| CN103539020B (en) | Novel hoisting construction method and special hanging device | |
| US8474633B2 (en) | Methods of removing a torque converter and a starting motor from an auxiliary compartment of a gas turbine | |
| CN104627849A (en) | Hoisting equipment and hoisting method for hoisting inner courtyard pipeline | |
| CN210529812U (en) | Special support for lifting large-scale component of excavator | |
| CN211169515U (en) | Lifting device for adjusting hydraulic cylinder of universal mill | |
| CN110002354B (en) | Hoisting system and hoisting method for heavy pipeline equipment in complex space | |
| CN205016899U (en) | Unsettled transformer mounting bracket | |
| CN215924210U (en) | Hoisting tool | |
| CN201092511Y (en) | Girder structure used for lifting large-scale generator | |
| CN221070772U (en) | Aerial disassembly device for crane boom of tower crane | |
| CN214003793U (en) | Lifting platform for mounting inner component of pipe culvert | |
| CN219279288U (en) | Lifting device | |
| CN216971707U (en) | Suspension arm tool |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20201211 |
|
| RJ01 | Rejection of invention patent application after publication |