CN216502971U - Laser welding pipe plugging device for water supply end of steam generator of high-temperature gas cooled reactor nuclear power station - Google Patents
Laser welding pipe plugging device for water supply end of steam generator of high-temperature gas cooled reactor nuclear power station Download PDFInfo
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- CN216502971U CN216502971U CN202123427994.XU CN202123427994U CN216502971U CN 216502971 U CN216502971 U CN 216502971U CN 202123427994 U CN202123427994 U CN 202123427994U CN 216502971 U CN216502971 U CN 216502971U
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Abstract
Steam generators are one of the key devices in high temperature gas cooled reactor nuclear power systems. The steam generator heat transfer tubes are an important component of the primary circuit pressure boundary and are an important barrier against the escape of radioactive fission products. The heat transfer pipe is easy to cause serious damage accidents under the action of high temperature, high pressure and high radiation for a long time, so that the plugging operation of the heat transfer pipe in the early stage of the failure is very important. The utility model provides a laser welding pipe plugging device for a water supply end of a steam generator of a high temperature gas cooled reactor nuclear power station based on a multi-axis robot and a laser welding process, aiming at a special structure of the water supply end of the steam generator of the high temperature gas cooled reactor. By utilizing the device, the precision and the automation degree of the pipe plugging operation of the water supply end can be improved, and the manual operation time is reduced. The utility model provides an innovative solution for laser welding pipe plugging at the water supply end of the steam generator of the high-temperature gas cooled reactor nuclear power station.
Description
Technical Field
The utility model belongs to the field of nuclear power technology and equipment, and particularly relates to a laser welding pipe plugging device for a water supply end of a steam generator of a high-temperature gas cooled reactor nuclear power station.
Background
High temperature gas cooled reactor (HTR-PM) nuclear power plants are highly economical and efficient, and are considered by the nuclear power community to be one of the most promising types of reactor to meet the requirements of the fourth generation advanced nuclear power equipment systems. A Steam Generator (SG) is one of the most critical devices in a high temperature gas cooled reactor (HTR-PM) nuclear power system. The steam generator is a heat exchange device which transfers the heat energy of the reactor to a two-loop medium to generate steam, and is a junction of the first loop and the second loop. The characteristics of the primary loop working medium which is a coolant with radioactivity and the secondary loop working medium which is non-radioactive steam provide very strict requirements on the contents related to safety and reliability, such as the structure, the strength, the corrosion resistance and the like of the steam generator. The steam generator of the high-temperature gas cooled reactor has a water supply end and a main steam outlet end and the like in functional structure, wherein the main steam outlet end provides steam power for the steam turbine set, and the water supply end is used for providing a circulating medium for the steam generator. The main steam outlet end and the water supply end both comprise tube plate structures for fixing heat transfer tubes, but the overall geometric shape, the space size, the installation position, the matched building facilities and the like of the main steam outlet end and the water supply end are different.
The heat transfer tubes are an important barrier against the escape of radioactive fission products and are also the weakest link in the steam generator. Whether the main steam outlet end or the water supply end is adopted, the heat transfer pipe in the pipe plate structure can be mechanically or chemically damaged under the action of high temperature, high pressure and high radiation for a long time, so that the heat transfer pipe is damaged, radioactive coolant leakage accidents occur, and serious social and environmental problems and huge economic losses are caused. The operation of plugging the heat transfer tube in the early stage of breakage or failure is a main means for preventing leakage of the radioactive cooling medium. At present, methods such as explosion pipe plugging, mechanical pipe plugging, welding pipe plugging and the like are mainly used for pipe plugging of the steam generator. Wherein, the explosion blocking pipe is easy to cause stress corrosion due to high residual stress and is basically not used any more; mechanical pipe plugging is a common method, and a large number of documents report mechanical plug design and pipe plugging device design (Zhanglijun, Jupeng super, Xue Xiang, etc. A roll expansion type mechanical plug for a nuclear power station steam generator heat transfer pipe is CN 203687745U [ P ]; Gong Weimin, Dingming. a rotation torque measurement and verification device for the steam generator heat transfer pipe is CN108267251A [ P ]; non-permanent fly, Yan Guohua, Von Lifa, etc. A steam generator mechanical pipe plugging contact analysis based on ANSYS [ J ] mechanical design and manufacture, 2012,000(004), (106-108); aiming at mechanical pipe blockage, mechanical devices for pipe blockage overhauling and operation are developed successively by Westinghouse company, Framatome-ANP company of AREVA group of France, Zetec company and the like in America, so that automation and intellectualization of mechanical pipe blockage operation are improved. However, a key problem with mechanical plugs is that the body expands under the action of the plug, causing high stress and plastic deformation. Compared with an SG system of an in-service pressurized water reactor, the service temperature of an SG heating pipe in the HTR-PM is higher, and the temperature of a primary side is increased to 750 ℃ from 343 ℃. The mechanical pipe plugging method applied to the conventional pressurized water reactor may cause pipe plugging failure due to stress relaxation at high temperature. The principle of welding the pipe plug is to use a welding means to partially fuse the plug material and the end material of the heat transfer pipe, so as to solve the problem of sealing failure easily caused by mechanical pipe plug. The prior art mainly utilizes traditional welding methods such as argon arc welding to realize the pipe blocking operation, and related work comprises designing a welding plug and researching the reliability problem of the plug (Zhao, Deng Xiaoyun, Xuxiao. design and evaluation of the steam generator welding pipe blocking plug [ J ] atomic energy science and technology, 50(7): 1270-. Most of the existing methods for welding and blocking pipes are in the research stage, and few cases report aiming at the automatic welding and blocking of the high-temperature gas cooled reactor steam generator or other types of steam generators on the working site.
Laser welding (laser welding) utilizes a laser beam as a heat source, has high energy density, small laser spot diameter, accurately controllable heat, small welding heat affected zone, high joint quality and good accessibility of the light beam, is suitable for precision machining, can effectively reduce welding deformation, and is widely applied to the field of equipment manufacturing industries such as automobiles, ships, aerospace and the like. Compared with welding processes such as argon arc welding and the like, the laser welding is expected to further improve the reliability and the sealing property of the plug pipe and further improve the welding quality and the welding precision of the plug, and the characteristic has important significance for further improving the operation safety of a nuclear power system. The laser welding pipe plugging technology aiming at the water supply end of the high-temperature gas cooled reactor steam generator mainly has the following problems: (1) how to realize the laser welding pipe plugging process according to the special structure of the water supply end? (2) How to improve the automation degree of the laser welding pipe plugging operation of the water supply end of the stack steam generator and reduce the short-range operation time of the operating personnel in the radiation environment? (3) How to solve the problem of equipment trafficability and enable the whole set of equipment to smoothly pass through a narrow transportation space? The problem is the key point for restricting the application of the laser welding technology to the pipe plugging operation of the water supply end of the steam generator of the high-temperature gas cooled reactor nuclear power station.
Disclosure of Invention
Aiming at the defects of the prior art, the utility model aims to provide a pipe blocking device for laser welding of a water supply end of a steam generator of a high-temperature gas-cooled reactor nuclear power station.
The technical scheme adopted by the utility model for solving the technical problem is as follows:
the laser welding pipe plugging device for the water supply end of the high-temperature gas cooled reactor steam generator comprises a welding plug 3, a multi-axis robot 7, a pneumatic clamping jaw 4, a clamping jaw quick-change connector 5, a laser head 6, a robot quick-change connector 8, an X-axis movement mechanism 9, a Y-axis movement mechanism 10, a Z-axis movement mechanism 11, a plug container box 12, a support frame 13, a camera 14 and a laser head quick-change connector 15;
the X-axis movement mechanism 9, the Y-axis movement mechanism 10 and the Z-axis movement mechanism 11 form a three-axis movement platform and are fixed on a support frame 13 through the X-axis movement mechanism 9; the chassis of the multi-axis robot 7 is fixed on the Z-axis motion mechanism 11 and can realize linear motion in the X/Y/Z direction under the drive of the three-axis motion platform;
the robot quick-change connector 8 is fixedly arranged at the front end of the multi-axis robot 7, the pneumatic claw 4 and the claw quick-change connector 5 are fixedly arranged, and the laser head quick-change connector 15 and the laser head 6 are fixedly arranged; the robot quick-change connector 8 can be respectively matched and connected with and separated from the jaw quick-change connector 5 or the laser head quick-change connector 15, namely, the robot quick-change connector 8 can be connected with the laser head quick-change connector 15 placed on the support frame 13 after loosening the jaw quick-change connector 5, and can be connected with the jaw quick-change connector 5 placed on the support frame 13 after loosening the laser head quick-change connector 15;
the welding plug 3 is placed in a plug container box 12, and the plug container box 12 is arranged on a support frame 13; the welding plug 3 can be grabbed by the pneumatic jack catch 4, conveyed under the drive of the multi-shaft robot 7 and inserted into a heat transfer pipe to be plugged on the water supply end pipe plate 2, so that the feeding of the welding plug 3 is realized;
the laser head 6 can be driven by the multi-axis robot 7 to move to the welding plug 3 arranged on the water supply end tube plate 2, and welding operation is realized along with the motion track of the multi-axis robot 7;
the camera 14 is arranged at a position at which the front end of the multi-axis robot 7 is not affected by the pneumatic clamping jaws 4 or the laser head 6, and the obtained image is used for judging the position of a fault heat transfer pipe on the water supply end pipe plate 2, the space position of the multi-axis robot 7 and the quality of welding operation.
Further, the multi-axis robot 7 is a six-axis robot and can avoid interference with the steam generator vessel 1 and the water supply end tube plate 2 through trajectory planning.
Further, the laser head 6 can receive an external laser source through an optical fiber, and can realize cooling or welding protection by connecting an external cooling medium or protective gas.
Further, the pneumatic jack catch 4, the jack catch quick-change connector 5, the laser head quick-change connector 15 and the robot quick-change connector 8 can be connected with a pressure air source through an air pipe to achieve required actions.
Furthermore, the multi-axis robot 7, the laser head 6 and other matching devices can bear certain nuclear power radiation, and the radiation resistance is not lower than 10 Gy/h.
Compared with the prior art, the utility model has the beneficial effects that: the laser welding process is applied to the pipe plugging operation of the water supply end of the steam generator of the high-temperature gas cooled reactor nuclear power station, and an actuating mechanism for realizing the pipe plugging operation of the laser welding is provided. The multi-axis movement mechanism is provided with image acquisition, so that the automation degree of the laser welding pipe plugging operation is improved, the short-range operation time of an operator in a radiation environment is reduced, and the positioning precision and the welding operation precision of the laser welding pipe plugging are improved; the device is miniaturized by combining the three-axis motion platform and the multi-axis robot, and is convenient to transport and install in a limited space. The utility model provides an innovative solution for the welding pipe blockage at the water supply end of the steam generator of the nuclear power station.
Drawings
Utility model
FIG. 1 is a perspective view of the device of the present invention.
Fig. 2 is a front view of the apparatus of the present invention.
Fig. 3 is a schematic view of the apparatus of the present invention with the steam generator vessel removed.
Fig. 4 is a schematic diagram of a multi-axis robot grabbing pneumatic claw in the device.
In the figure: the automatic welding device comprises a steam generator container, a water feeding end tube plate 2, a welding plug 3, a pneumatic clamping jaw 4, a clamping jaw quick-change connector 5, a laser head 6, a multi-axis robot 7, a robot quick-change connector 8, a 9X-axis motion mechanism, a 10Y-axis motion mechanism, an 11Z-axis motion mechanism, a 12 plug container box, a 13 supporting frame, a 14 camera and a 15 laser head quick-change connector.
Detailed Description
The utility model is further described below with reference to the accompanying drawings.
As shown in fig. 1, fig. 2, fig. 3 and fig. 4, the pipe blocking device for laser welding of the water supply end of the high temperature gas cooled reactor steam generator comprises a welding plug 3, a multi-axis robot 7, a pneumatic clamping jaw 4, a clamping jaw quick-change connector 5, a laser head 6, a robot quick-change connector 8, an X-axis movement mechanism 9, a Y-axis movement mechanism 10, a Z-axis movement mechanism 11, a plug container box 12, a support frame 13, a camera 14 and a laser head quick-change connector 15;
the X-axis movement mechanism 9, the Y-axis movement mechanism 10 and the Z-axis movement mechanism 11 form a three-axis movement platform and are fixed on a support frame 13 through the X-axis movement mechanism 9; the chassis of the multi-axis robot 7 is fixed on the Z-axis motion mechanism 11 and can realize linear motion in the X/Y/Z direction under the drive of the three-axis motion platform;
the robot quick-change connector 8 is fixedly arranged at the front end of the multi-axis robot 7, the pneumatic claw 4 and the claw quick-change connector 5 are fixedly arranged, and the laser head quick-change connector 15 and the laser head 6 are fixedly arranged; the robot quick-change connector 8 can be respectively matched and connected with and separated from the jaw quick-change connector 5 or the laser head quick-change connector 15, namely, the robot quick-change connector 8 can be connected with the laser head quick-change connector 15 placed on the support frame 13 after loosening the jaw quick-change connector 5, and can be connected with the jaw quick-change connector 5 placed on the support frame 13 after loosening the laser head quick-change connector 15;
the welding plug 3 is placed in a plug container box 12, and the plug container box 12 is arranged on a support frame 13; the welding plug 3 can be grabbed by the pneumatic jack catch 4, conveyed under the drive of the multi-shaft robot 7 and inserted into a heat transfer pipe to be plugged on the water supply end pipe plate 2, so that the feeding of the welding plug 3 is realized;
the laser head 6 can be driven by the multi-axis robot 7 to move to the welding plug 3 arranged on the water supply end tube plate 2, and welding operation is realized along with the motion track of the multi-axis robot 7;
the camera 14 is arranged at a position at which the front end of the multi-axis robot 7 is not affected by the pneumatic clamping jaws 4 or the laser head 6, and the obtained image is used for judging the position of a fault heat transfer pipe on the water supply end pipe plate 2, the space position of the multi-axis robot 7 and the quality of welding operation.
The multi-axis robot 7 is a six-axis robot and can avoid interference with the steam generator container 1 and the water supply end pipe plate 2 through trajectory planning.
The laser head 6 can receive an external laser source through an optical fiber and can realize cooling or welding protection by connecting an external cooling medium or protective gas.
The pneumatic jack catch 4, the jack catch quick-change connector 5, the laser head quick-change connector 15 and the robot quick-change connector 8 can be connected with a pressure air source through an air pipe to realize required actions.
The multi-axis robot 7, the laser head 6 and other matching devices can bear certain nuclear power radiation, and the radiation resistance is not lower than 10 Gy/h.
As shown in fig. 1 to 4, the robot-based laser welding pipe plugging device for the water supply end of the steam generator of the high temperature gas cooled reactor nuclear power station has the following working principle:
a robot quick-change connector 8 is arranged at an executing end of the multi-axis robot 7, and the robot quick-change connector 8 can be matched with a laser head quick-change connector 15 or a claw quick-change connector 5 to realize automatic installation and separation and replacement. The principle is that a modularized connector is adopted, the robot quick-change connector 8 is set to be a male connector, the laser head quick-change connector 15 and the jaw quick-change connector 5 are set to be female connectors, and when the robot quick-change connector 8 is installed or separated from the laser head quick-change connector 15 or the jaw quick-change connector 5, opening and closing actions are achieved through a pneumatic actuating element integrated on the connector.
When the plug 3 needs to be welded for feeding, the executing tail end of the multi-axis robot 7 runs to the pneumatic clamping jaw 4, and is connected with the pneumatic clamping jaw 4 through the clamping and rotating quick-change connector 5. After the pneumatic clamping jaw 4 is installed, the multi-axis robot 7 drives the pneumatic clamping jaw 4 to grab the welding plug 3 in the plug container box 12 and convey the welding plug to the position of the heat transfer pipe to be plugged of the water supply end pipe plate 2. After the plug 3 to be welded is correctly inserted into the heat transfer pipe, the pneumatic clamping jaw 4 loosens the welding plug 3, the pneumatic clamping jaw 4 moves to the position near the support frame 13, the pneumatic clamping jaw 4 is loosened through the matching of the robot quick-change connector 8 and the clamping jaw quick-change connector 5, and the pneumatic clamping jaw 4 and the clamping jaw quick-change connector 5 are placed on the support frame 13.
After the welding plugs 3 are assembled and loaded, the multi-axis robot 7 installs the laser head 6 through the laser head quick-change connector 15, conveys the laser head 6 to the welding plugs 3 which are assembled and inserted near the water supply end pipe plate 2, and carries out welding operation. And the welding operation is carried out according to the movement track compiled in the earlier stage and the processing parameters. After the welding operation is completed, the multi-axis robot 7 conveys the laser head 6 to the vicinity of the support frame 13 and then disconnects the laser head 6 and the laser head quick-change connector 15, and the laser head 6 and the laser head quick-change connector 15 are placed on the support frame 13.
In order to smoothly realize grabbing of the multi-axis robot 7 to the welding plug 3, fault assessment of the water supply end pipe plate 2, positioning operation of installing and inserting the welding plug 3, positioning operation of installing and replacing the laser head 6, obstacle avoidance of the steam generator container 1 and the water supply end pipe plate 2 and the like, a camera 14 is installed at the executing tail end of the multi-axis robot 7. The above functions are realized according to the image collected by the camera 14 and by combining an image processing method, a machine vision method and the like.
Claims (5)
1. The high temperature gas cooled reactor nuclear power station steam generator water supply end laser welding pipe blocking device is characterized in that: the welding device comprises a welding plug (3), a multi-axis robot (7), a pneumatic clamping jaw (4), a clamping jaw quick-change connector (5), a laser head (6), a robot quick-change connector (8), an X-axis movement mechanism (9), a Y-axis movement mechanism (10), a Z-axis movement mechanism (11), a plug container box (12), a support frame (13), a camera (14) and a laser head quick-change connector (15);
the X-axis movement mechanism (9), the Y-axis movement mechanism (10) and the Z-axis movement mechanism (11) form a three-axis movement platform and are fixed on a support frame (13) through the X-axis movement mechanism (9); the chassis of the multi-axis robot (7) is fixed on a Z-axis motion mechanism (11) and can realize linear motion in the X/Y/Z direction under the drive of a three-axis motion platform;
the robot quick-change connector (8) is fixedly arranged at the front end of the multi-axis robot (7), the pneumatic clamping jaw (4) and the clamping jaw quick-change connector (5) are fixedly arranged, and the laser head quick-change connector (15) and the laser head (6) are fixedly arranged; the robot quick-change connector (8) can be mutually matched and connected and separated with the jaw quick-change connector (5) or the laser head quick-change connector (15) respectively, namely, the robot quick-change connector (8) is connected with the laser head quick-change connector (15) placed on the support frame (13) after the jaw quick-change connector (5) is loosened, and is connected with the jaw quick-change connector (5) placed on the support frame (13) after the laser head quick-change connector (15) is loosened;
the welding plug (3) is placed in a plug container box (12), and the plug container box (12) is arranged on a support frame (13); the welding plug (3) is grabbed by a pneumatic jack catch (4), is driven by a multi-axis robot (7) to be conveyed and inserted into a heat transfer pipe to be plugged on the water supply end pipe plate (2), and the feeding of the welding plug (3) is realized;
the laser head (6) is driven by the multi-axis robot (7) to move to a welding plug (3) arranged on the water supply end tube plate (2), and welding operation is realized along with the motion track of the multi-axis robot (7);
the camera (14) is arranged at the front end of the multi-axis robot (7) and is not influenced by the pneumatic clamping jaw (4) or the laser head (6), and the obtained image is used for judging the position of a fault heat transfer pipe on the water supply end tube plate (2), the space position of the multi-axis robot (7) and the quality of welding operation.
2. The laser welding pipe plugging device for the water supply end of the steam generator of the high-temperature gas-cooled reactor nuclear power station as claimed in claim 1, wherein: the multi-axis robot (7) is a six-axis robot and can avoid interference with the steam generator container (1) and the water supply end pipe plate (2) through trajectory planning.
3. The laser welding pipe plugging device for the water supply end of the steam generator of the high-temperature gas-cooled reactor nuclear power station as claimed in claim 1, wherein: the laser head (6) can receive an external laser source through an optical fiber and can realize cooling or welding protection by connecting an external cooling medium or protective gas.
4. The laser welding pipe plugging device for the water supply end of the steam generator of the high-temperature gas-cooled reactor nuclear power station as claimed in claim 1, wherein: pneumatic jack catch (4), jack catch quick-change coupler (5), laser head quick-change coupler (15) and robot quick-change coupler (8) can realize required action through trachea connection pressure air supply.
5. The laser welding pipe plugging device for the water supply end of the steam generator of the high-temperature gas-cooled reactor nuclear power station as claimed in claim 1, wherein: the multi-axis robot (7), the laser head (6) and the matching device thereof can bear certain nuclear power radiation, and the irradiation resistance is not lower than 10 Gy/h.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123427994.XU CN216502971U (en) | 2021-12-31 | 2021-12-31 | Laser welding pipe plugging device for water supply end of steam generator of high-temperature gas cooled reactor nuclear power station |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202123427994.XU CN216502971U (en) | 2021-12-31 | 2021-12-31 | Laser welding pipe plugging device for water supply end of steam generator of high-temperature gas cooled reactor nuclear power station |
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| CN216502971U true CN216502971U (en) | 2022-05-13 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202123427994.XU Active CN216502971U (en) | 2021-12-31 | 2021-12-31 | Laser welding pipe plugging device for water supply end of steam generator of high-temperature gas cooled reactor nuclear power station |
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| CN (1) | CN216502971U (en) |
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2021
- 2021-12-31 CN CN202123427994.XU patent/CN216502971U/en active Active
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