A synchronous hoisting mechanism of a special machine for repairing a sealed weld

Abstract

The application provides a synchronous hoisting mechanism of a special machine for repairing a sealing weld, which comprises a plurality of clamping modules for being fixed on a scaffold platform, a hoisting frame and a synchronous hoisting module installed on the hoisting frame, the scaffold platform is arranged above a control rod drive mechanism to be repaired, the clamping module comprises a supporting leg fixing seat, the hoisting frame comprises a plurality of supporting legs and a supporting beam, the number of the supporting legs is the same as that of the supporting leg fixing seats, the lower ends of all the supporting legs are connected to all the supporting leg fixing seats one by one, the upper ends of the supporting legs are connected to the end portions of the supporting beam, the synchronous hoisting module comprises a fixing disc installed on the supporting beam, a plurality of groups of fixed pulley sets installed on the fixing disc and a plurality of groups of movable pulley sets connected to all the fixed pulley sets through pull ropes, and a lifting hook for being connected to a lifting opening of the special machine for repairing a sealing weld is installed on each group of the movable pulley sets. The synchronous hoisting mechanism can realize stable hoisting of the special machine.

Description

Technical Field

[0001] This invention relates to the field of sealing weld repair technology for a control rod drive mechanism, and in particular to a synchronous hoisting mechanism for a special machine for sealing weld repair. Background Technology

[0002] The control rod drive mechanism (CRDM) is the servo mechanism of the nuclear power plant reactor control and safety protection system, used for reactor start-up, shutdown, power regulation, and emergency shutdown. Multiple CRDMs are distributed on the reactor pressure vessel top cover, each with multiple sealing welds from bottom to top, varying depending on the reactor type. These sealing welds serve a sealing function and must not leak throughout their entire lifespan. However, based on domestic and international nuclear power plant operation experience, leaks in these sealing welds are a frequent type of failure, seriously jeopardizing the safe operation of the nuclear power plant and requiring in-service maintenance via specialized maintenance equipment. Sealing weld repair work is conducted in a confined space, and the CRDM (Credit Reinforcing Duct Detachment) is a vertical, long rod structure, densely and evenly distributed above the pressure vessel cover, making installation of the dedicated machine difficult. Currently, both domestically and internationally, the installation of dedicated machines for sealing weld repair typically involves erecting scaffolding and manually climbing to the top of the cover for installation and positioning. This method suffers from poor personnel accessibility, limited working space, and high radiation exposure. Furthermore, existing hoisting ropes are insufficient to meet the requirements for installing the repair machine onto the CRDM travel sleeve. Hoisting with a single rope easily causes the machine to tilt, while multiple ropes require very long ropes to accommodate the travel sleeve connection, occupying space in the plant's hoisting area and disrupting other on-site operations. To improve this technical situation and ensure stable and convenient installation of the repair machine, a safe, reliable, and easy-to-operate synchronous hoisting mechanism for sealing weld repair machines needs to be developed. Summary of the Invention

[0003] In view of the shortcomings of the prior art described above, the technical problem to be solved by the present invention is to provide a synchronous hoisting mechanism for sealing weld maintenance machines that can achieve stable hoisting of maintenance machines, reduce the radiation dose to operators, and save maintenance time.

[0004] To achieve the above objectives, the present invention provides a synchronous hoisting mechanism for a special machine for sealing weld repair, comprising multiple clamping modules for fixing on a scaffold platform, a hoisting frame, and a synchronous hoisting module mounted on the hoisting frame. The scaffold platform is erected above the control rod drive mechanism to be repaired. The clamping module includes a leg fixing seat. The hoisting frame includes multiple legs and a support beam. The number of legs is the same as the number of leg fixing seats. The lower ends of all the legs are connected to all the leg fixing seats one by one, and the upper ends of the legs are connected to the ends of the support beams. The synchronous hoisting module includes a fixed plate mounted on the support beam, multiple sets of fixed pulley groups mounted on the fixed plate, and multiple sets of movable pulley groups connected to all the fixed pulley groups by pull ropes. Each set of movable pulley groups is equipped with a hook for connecting to the hoisting port of the special machine for sealing weld repair.

[0005] Furthermore, the synchronous hoisting module also includes a guide rail fixedly installed on the support beam and a slider that cooperates with the guide rail, and the fixing plate is fixedly installed on the slider.

[0006] Furthermore, there are three clamping modules and three legs. The three legs are respectively mounted on the leg fixing seats of the three clamping modules. The support beam includes a connecting beam and a crossbeam. The two ends of the crossbeam are respectively connected to the ends of two of the legs. The two ends of the connecting beam are respectively connected to the middle of the crossbeam and the end of the other leg. The guide rail is fixedly mounted on the connecting beam.

[0007] Furthermore, the side of the fixed disk is connected to the fixed clamping mechanism via a connecting plate. The fixed clamping mechanism includes a bidirectional screw and a clamping block is disposed on the bidirectional screw. By rotating the bidirectional screw, the clamping block can be moved until it clamps the guide rail.

[0008] Furthermore, one end of the pull rope is fixed to the scaffolding platform, and the other end of the pull rope is wound around a ratchet winch, which is fixed to the scaffolding platform.

[0009] Furthermore, there are 4 sets of fixed pulleys and 3 sets of movable pulleys, with the 3 sets of movable pulleys distributed at intervals along the circumference of the fixed plate.

[0010] Furthermore, the fixed pulley block includes a rope guide block, a threaded fixing block fixed relative to the rope guide block, a embossed screw installed in the threaded fixing block through a threaded engagement, and a clamping block disposed at the end of the embossed screw. The pull rope is threaded between the rope guide block and the threaded fixing block. When the embossed screw is tightened, it can push the clamping block to press the pull rope onto the rope guide block.

[0011] Furthermore, the contact surface between the clamping block and the pull rope is provided with a mesh pattern.

[0012] Furthermore, the clamping module includes a clamping base plate, an upper clamping plate, and a lower clamping plate. The lower end of the upper clamping plate is movably connected to the middle of the clamping base plate, and the upper end of the lower clamping plate is movably connected to the middle of the clamping base plate. The upper and lower ends of the clamping base plate are respectively hinged to two swivel bolts. The two swivel bolts are respectively inserted into the elongated holes of the upper clamping plate and the lower clamping plate, and each of the two swivel bolts is equipped with a horn nut.

[0013] Furthermore, the upper end of the clamping base plate is provided with a stepped structure, and the support leg fixing seat is fixedly installed on the stepped structure of the clamping base plate by an upper quick-release pin.

[0014] As described above, the synchronous hoisting mechanism for sealing weld repair machines of the present invention has the following beneficial effects:

[0015] The entire synchronous hoisting mechanism adopts a modular design with a frame structure, making on-site installation convenient and operation simple. By using ropes in combination with moving and fixed pulley blocks, it can achieve synchronous lifting and lowering of multiple hoisting points, enabling stable and reliable hoisting and installation of maintenance equipment. This replaces manual climbing operations, effectively reducing the radiation dose to workers, saving maintenance time, and thus improving the operating efficiency of nuclear power plants.

[0016] In addition, the span of each connecting module of this synchronous hoisting mechanism is adjustable, and the clamping module has a large clamping size range. The installation position can be adjusted by moving the guide rail to complete the synchronous hoisting needs of different types of maintenance machines and different stack types at the maintenance site. It can also be extended to other industries for similar synchronous hoisting needs. Furthermore, by setting multiple clamping self-locking structures, the stability and reliability of hoisting and installing maintenance machines are further improved. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the synchronous hoisting mechanism of the special machine for repairing sealed welds in an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the clamping module in an embodiment of the present invention.

[0019] Figure 3 This is a schematic diagram of the assembly of the fixed pulley block, fixed plate and guide rail in an embodiment of the present invention.

[0020] Figure 4 This is a schematic diagram of the connection structure between the fixed pulley block, Kevlar rope, and movable pulley block in an embodiment of the present invention.

[0021] Figure 5 This is a schematic diagram of the fixed pulley system in an embodiment of the present invention.

[0022] Figure 6 This is a schematic diagram of the working state of the synchronous hoisting mechanism of the special machine for sealing weld repair in an embodiment of the present invention.

[0023] Component designation explanation

[0024] 1-Clamping module; 101-Clamping base plate; 102-Lower quick release pin; 103-Swivel bolt; 104-Lower clamping plate; 105-Flat-headed cylindrical pin; 106-Upper clamping plate; 107-Upper quick release pin; 108-Leg fixing seat;

[0025] 2-Lifting frame; 201-Outrigger; 202-Connecting beam; 203-Crossbeam; 204-End stop; 205-Diagonal brace; 206-Connecting block;

[0026] 3-Synchronous hoisting module; 301-Fixed pulley block; 302-Guide rail; 303-Slider; 304-Lifting lug; 305-Fixed plate; 306-Connecting plate; 307-Fixed clamping mechanism; 308-Hook; 309-Moving pulley block; 310-Kevlar rope; 311-Side connecting plate; 312-Small pulley; 313-Small shaft; 314-Large pulley; 315-Large shaft; 316-Side reinforcing plate; 317-Adapter block; 318-Threaded pin; 319-U-shaped lifting ring; 320-Clamping block; 321-Threaded fixing block; 322-Etched threaded rod; 323-Rope guide block; 324-Clamping support plate; 325-Clamping quick-release pin;

[0027] 4-Maintenance machine; 5-Scaffolding platform; 6-Ratchet winch; 7-Stroke sleeve; 8-Sealing weld; 9-Control rod drive mechanism; 10-Reactor pressure vessel top cover. Detailed Implementation

[0028] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0029] It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings of this specification are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed in this invention. Furthermore, terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention's implementation.

[0030] like Figures 1 to 6As shown, this embodiment provides a synchronous hoisting mechanism for a special machine for repairing sealed welds, which includes:

[0031] The clamping module 1 consists of a clamping base plate 101, a lower quick-release pin 102, a swivel bolt 103, a lower clamping plate 104, a flat-headed cylindrical pin 105, an upper clamping plate 106, and a support leg fixing seat 108. The clamping module 1 is the fixing module of the entire synchronous hoisting mechanism, fixedly clamped to the round or square tube of the scaffolding platform 5. Multiple clamping modules 1 work together. The main body of the clamping module 1 is the clamping base plate 101, which has three lug structures from bottom to top. The swivel bolt 103 is fixedly installed in the upper and lower lug structures by the lower quick-release pin 102, allowing the swivel bolt 103 to rotate freely after mating. The middle lug structure is connected to the lower... The upper end of the clamping plate 104 and the lower end of the upper clamping plate 106 have an elongated hole in the middle of the upper and lower clamping plates. The swivel bolt 103 passes through the hole and is limited by the horn nut. The lower clamping plate 104 and the upper clamping plate 106 can rotate. The upper part of the clamping base plate 101 has a stepped structure, which forms a supporting structure with the support leg fixing seat 108 and is locked by the upper quick release pin 107. The clamping module 1 clamps two scaffolding steel pipes through the upper and lower clamping plates and is locked and fixed by the horn nut on the swivel bolt 103.

[0032] The hoisting frame 2 consists of outriggers 201, connecting beams 202, crossbeams 203, end blocks 204, diagonal braces 205, and connecting blocks 206. The hoisting frame 2 is a frame structure and supports the entire synchronous hoisting mechanism. The lower part of the hoisting frame 2 consists of three outriggers 201, which are respectively installed in outrigger fixing seats 108 and fixed by screws. Connecting beams 202 and crossbeams 203 are mounted on top of the outriggers 201, and each joint is fixed by connecting blocks 206 with screws. Diagonal braces 205 reinforce the connection between the connecting beams 202 and one outrigger 201.

[0033] The synchronous lifting module 3 consists of a fixed pulley block 301, a guide rail 302, a slider 303, a lifting lug 304, a fixed plate 305, a connecting plate 306, a fixed clamping mechanism 307, a hook 308, a movable pulley block 309, a Kevlar rope 310, a side connecting plate 311, a small pulley 312, a small rotating shaft 313, a large pulley 314, a large rotating shaft 315, a side reinforcing plate 316, a transition block 317, a threaded pin 318, a U-shaped lifting ring 319, a clamping block 320, a threaded fixing block 321, a textured screw 322, a rope guide block 323, a clamping support plate 324, and a clamping quick-release pin 325. In this embodiment, the pull rope is specifically a Kevlar rope 310.The synchronous hoisting module 3 is installed and fixed below the connecting beam 202 of the hoisting frame 2 via guide rail 302 and is fixedly connected by screws. Multiple mating sliders 303 are provided on the guide rail 302, and end blocks 204 are provided at both ends of the guide rail 302 to prevent the sliders 303 from falling off. A fixing plate 305 is fixedly installed on the lower part of the slider 303. The right side of the fixing plate 305 is connected to the fixing clamping mechanism 307 via a connecting plate 306. The fixing clamping mechanism 307 is provided with a bidirectional screw and a clamping block. The clamping block can be clamped to the side of the guide rail 302 by rotating the screw to fix the position of the hoisting module on the guide rail 302. The fixed plate 305 can drive other components to slide on the guide rail 302; three lifting lugs 304 are evenly distributed below the fixed plate 305, two of which have a fixed pulley group 301 hanging below them, and one of the lifting lugs 304 has two fixed pulley groups 301 hanging below it; in this embodiment, the fixed pulley group 301 is a double pulley structure, with two side connecting plates 311 supporting the entire fixed pulley group 301. The lower part is fixedly connected to the small pulley 312 through the small rotating shaft 313, and the middle part is fixedly connected to the large pulley 314 through the large rotating shaft 315. Each pulley is equipped with a rotating bearing and can rotate freely; the upper part is connected to the adapter Blocks 317 are fixedly connected together. The adapter block 317 is connected to the U-shaped lifting ring 319 through the threaded pin 318. The fixed pulley block 301 can be hung below the lifting lug 304 through the U-shaped lifting ring 319. A side reinforcing plate 316 is provided on the outer side of the side connecting plate 311 to improve the rigidity and stability of the entire pulley block. A clamping support plate 324 is provided on the outer side of the side reinforcing plate 316. One end can rotate along the large rotating shaft 315, and the other end is connected to the rope guide block 323 and the threaded fixing block 321. The embossed screw 322 is installed inside the threaded fixing block 321 through threaded engagement. The end of the embossed screw 322 is engaged with... A clamping block 320 is provided. When the embossed screw 322 is tightened, the clamping block 320 can move linearly inward to clamp the Kevlar rope 310 that passes between the rope guide block 323 and the threaded fixing block 321. The embossed screw 322 is self-locking, and the contact surface between the clamping block 320 and the Kevlar rope 310 is provided with a textured surface to prevent the Kevlar rope 310 from coming off. The clamping support plate 324 has multiple fixing holes, which can be fixed to the side connecting plate 311 by clamping quick release pins 325. The rotation angle of the clamping support plate 324 can be adjusted to adapt to the tension angle of the Kevlar rope 310 under different working conditions.In this embodiment, a Kevlar rope 310 is threaded inside the fixed pulley block 301. The Kevlar rope 310 is also threaded inside the three movable pulley blocks 309. A single rope runs through the three movable pulley blocks 309 and the four fixed pulley blocks 301. The two ends of the Kevlar rope 310 are respectively threaded onto the large pulleys 314 of the fixed pulley block 301 and between the rope guide block 323 and the threaded fixing block 321. It can be tightened by the embossed screw 322. The two ends of the Kevlar rope 310 are tied to the scaffolding. A hook 308 is provided below the movable pulley block 309 for connecting to the hoisting port of the maintenance machine. When one end of the Kevlar rope 310 is fixed, the other end can be manually loosened or tightened. The three hooks 308 below the movable pulley block 309 can be lowered and raised simultaneously, thereby driving the maintenance machine to be hoisted smoothly.

[0034] The following is combined with Figures 1 to 6 This section describes the specific implementation process of the synchronous hoisting mechanism for the special machine used for repairing sealed welds:

[0035] When repairing the sealing weld 8 of a certain type of control rod drive mechanism 9 using a special machine 4 for sealing weld repair, if... Figure 6 As shown, the reactor pressure vessel top cover 10 is hoisted to the storage area, the peripheral components of the control rod drive mechanism 9 are removed, and a scaffolding platform 5 is erected above the control rod drive mechanism 9 to be repaired. Taking the central sealing weld 8 of a certain reactor type as an example, the specific implementation steps of the synchronous hoisting mechanism are as follows:

[0036] Non-destructive testing revealed a leak in the sealing weld 8 in the middle of a certain stack type, requiring repair work. The repair machine 4 was hoisted and placed on the scaffolding platform 5. A synchronous hoisting mechanism was installed: first, three clamping modules 1 were installed onto the steel pipes of the scaffolding fence and clamped and locked; the assembled hoisting frame 2 and synchronous hoisting module 3 were installed in the leg fixing seat 108 of the clamping module 1 via outriggers 201 and locked with quick-release screws; one end of the Kevlar rope 310 was pressed and locked by the rope guide block 323 and the threaded fixing block 321, and the other end... The end is tightly wound onto the hand-cranked ratchet winch 6, and the ratchet winch 6 is fixed to the steel pipe of the railing of the scaffolding platform 5. The Kevlar rope 310 on the ratchet winch 6 is loosened, allowing the three movable pulley blocks 309 to be lowered to a suitable height. The hook 308 below the movable pulley blocks 309 is connected to the lifting lug above the maintenance machine 4. The Kevlar rope 310 is slowly tightened by the ratchet winch 6, and the maintenance machine 4 is smoothly lifted to a suitable height. The Kevlar rope 310 on the side of the ratchet winch 6 is locked by the rope guide block 323 and the threaded fixing block 321. Verification With the clamping mechanism 307 in the released state, release the rope and manually push the fixing plate 305 and the maintenance machine 4 to the outside of the scaffolding platform 5, to the cantilever area of ​​the connecting beam 202 of the hoisting frame 2, i.e., above the area to be maintained; lock the fixing plate 305 using the clamping mechanism 307; unlock the Kevlar rope 310 on the side of the ratchet winch 6 using the rope guide block 323 and the threaded fixing block 321; release the Kevlar rope 310 using the ratchet winch 6, allowing the maintenance machine 4 to be lowered slowly and smoothly, and use a long-handled tool to assist in positioning it to the control rod drive mechanism. Above the travel sleeve 7 of position 9, the maintenance machine 4 is mounted on the outer wall of the travel sleeve 7. The maintenance machine 4 is then lowered to the sealing weld 8, and the Kevlar rope 310 is locked. The maintenance machine 4 performs maintenance work. After the maintenance work is completed, the Kevlar rope 310 is released, and the Kevlar rope 310 is tightened by the ratchet winch 6, so that the maintenance machine 4 is smoothly raised to the upper position. The Kevlar rope 310 is locked, and the fixed plate 305 and the maintenance machine 4 are pushed by hand to the scaffolding platform 5 area. The maintenance machine 4 is then lowered, completing the entire hoisting operation.

[0037] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0038] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A synchronous hoisting mechanism for special machines used for repairing sealed welds, characterized in that, The system includes multiple clamping modules for fixing to a scaffolding platform, a hoisting frame, and a synchronous hoisting module installed on the hoisting frame. The scaffolding platform is erected above the control rod drive mechanism to be repaired. The clamping module includes a leg fixing seat. The hoisting frame includes multiple legs and a support beam. The number of legs is the same as the number of leg fixing seats. The lower ends of all the legs are connected to all the leg fixing seats one by one. The upper ends of the legs are connected to the ends of the support beams. The synchronous hoisting module includes a fixed plate installed on the support beam, multiple sets of fixed pulleys installed on the fixed plate, and multiple sets of movable pulleys connected to all the fixed pulleys by pull ropes. Each set of movable pulleys is equipped with a hook for connecting to the hoisting port of the special machine for repairing sealed welds. The clamping module includes a clamping base plate, an upper clamping plate, and a lower clamping plate. The lower end of the upper clamping plate is movably connected to the middle of the clamping base plate, and the upper end of the lower clamping plate is movably connected to the middle of the clamping base plate. The upper and lower ends of the clamping base plate are respectively hinged to two swivel bolts. The two swivel bolts pass through the elongated holes of the upper clamping plate and the lower clamping plate, respectively, and each of the two swivel bolts is equipped with a horn nut. The upper end of the clamping base plate is provided with a stepped structure, and the support leg fixing seat is fixedly installed on the stepped structure of the clamping base plate by an upper quick-release pin.

2. The synchronous hoisting mechanism for sealing weld repair as described in claim 1, characterized in that, The synchronous hoisting module also includes a guide rail fixedly installed on the support beam and a slider that cooperates with the guide rail, and the fixing plate is fixedly installed on the slider.

3. The synchronous hoisting mechanism for sealing weld repair as described in claim 2, characterized in that, There are three clamping modules and three legs. The three legs are respectively installed on the leg fixing seats of the three clamping modules. The support beam includes a connecting beam and a crossbeam. The two ends of the crossbeam are respectively connected to the ends of two of the legs. The two ends of the connecting beam are respectively connected to the middle of the crossbeam and the end of the other leg. The guide rail is fixedly installed on the connecting beam.

4. The synchronous hoisting mechanism for sealing weld repair as described in claim 2, characterized in that, The side of the fixed plate is connected to the fixed clamping mechanism via a connecting plate. The fixed clamping mechanism includes a bidirectional screw and a clamping block is disposed on the bidirectional screw. By rotating the bidirectional screw, the clamping block can be moved until it clamps the guide rail.

5. The synchronous hoisting mechanism for sealing weld repair as described in claim 1, characterized in that, One end of the pull rope is fixed to the scaffolding platform, and the other end of the pull rope is wound around a ratchet winch, which is fixed to the scaffolding platform.

6. The synchronous hoisting mechanism for sealing weld repair as described in claim 1, characterized in that, There are 4 sets of fixed pulleys and 3 sets of movable pulleys, with the 3 sets of movable pulleys distributed at intervals along the circumference of the fixed plate.

7. The synchronous hoisting mechanism for sealing weld repair as described in claim 1, characterized in that, The fixed pulley assembly includes a rope guide block, a threaded fixing block fixed relative to the rope guide block, a embossed screw installed in the threaded fixing block through a threaded engagement, and a clamping block disposed at the end of the embossed screw. The pull rope is threaded between the rope guide block and the threaded fixing block. When the embossed screw is tightened, it can push the clamping block to press the pull rope against the rope guide block.

8. The synchronous hoisting mechanism for sealing weld repair as described in claim 7, characterized in that, The contact surface between the clamping block and the pull rope is provided with a mesh pattern.

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