Nuclear power plant nuclear class temperature element dismounting device

Abstract

The present application relates to the technical field of nuclear power plant overhaul tools, in particular to a nuclear power plant nuclear grade temperature element dismounting device, comprising a stretching assembly and a knocking loose assembly; the stretching assembly comprises a mounting block, a sliding block slidingly connected to the mounting block and a lead screw rotatably connected to the mounting block, and the sliding block is threadedly connected to the lead screw; an upper clamping plate for connecting the temperature element is arranged on the sliding block, and a lower clamping plate for connecting a protective sleeve is arranged on the mounting block; the knocking loose assembly comprises an upper end plate, a metal rod, a lower end plate, a sliding rod and a sliding hammer slidingly connected to the sliding rod which are sequentially fixedly connected; the upper end plate is located between the upper clamping plate and the temperature element; and the protective sleeve is located between the upper end plate and the lower end plate. The device reduces the pulling-out resistance of the temperature element, avoids the breakage of the temperature element during dismounting, improves the dismounting success rate and operation efficiency and reduces the scrap loss of the temperature element.

Description

Technical Field

[0001] This invention relates to the technical field of nuclear power plant maintenance tools, specifically a device for disassembling nuclear-grade temperature elements in nuclear power plants. Background Technology

[0002] Nuclear-grade temperature elements (RTD resistance thermometers) are important safety-grade measuring instruments for pressurized water reactor nuclear power units. They are widely used in key locations such as reactor loops and main equipment to collect medium temperature signals and provide reliable temperature data for unit control and protection systems. They are key instrumentation and control components that ensure the safe and stable operation of nuclear power plants.

[0003] To meet the requirements of RTD response time testing, the gap between the temperature element and the protective sleeve is designed to be very small, especially in nuclear-grade temperature elements. The outer wall of the sensing part is almost in direct contact with the inner wall of the protective sleeve to allow the protective sleeve to quickly transfer the heat of the tested medium to the temperature element, ensuring the element's response speed. However, an excessively small gap between the element and the protective sleeve makes removing the temperature element very difficult. After thermal expansion, the temperature element will come into close contact with the inner wall of the sleeve, severely reducing the efficiency of maintenance and replacement. Forced removal can easily cause the temperature element to break during the removal process, resulting in direct economic losses. To address this technical problem, existing technologies have designed dedicated removal devices for temperature elements, such as "A tool for removing a temperature element" (Publication No.: CN221338381U). This tool uses two adjustable fixed side plates to fix the sleeve, a conical rod to hold the temperature element in place, and then a sliding hammer connected to the conical rod to impact the fixed block on the conical rod, thereby gradually pulling the temperature element out of the sleeve. While this method can achieve the removal of the temperature element, it still has the following technical problems: Because the temperature element is equipped with a bellows, the bellows serves two purposes: firstly, it seals the opening between the temperature element and the sleeve, preventing heat loss and ensuring accurate temperature detection; secondly, when the temperature element is inserted into the sleeve, it compresses the bellows, causing it to expand. The expanded bellows then tightens the inner wall of the sleeve, increasing the connection strength between the temperature element and the sleeve. However, the existing disassembly device uses a sliding hammer to impact and push the temperature element with a cone rod, relying on impact force to eject it. Because the elastic tension of the bellows increases resistance, repeated impacts are required, and very large impact forces are needed to loosen the temperature element. Under repeated impacts, the temperature element inside the sleeve is very prone to deformation or even breakage, directly rendering it unusable. Summary of the Invention

[0004] This invention provides a nuclear power plant nuclear-grade temperature element disassembly device, which can solve the problem that in the prior art, temperature elements need to be loosened by impact force throughout the disassembly process, which can easily lead to deformation or even breakage of the temperature elements, resulting in the scrapping of the temperature elements.

[0005] This application provides the following technical solution: a power plant nuclear-grade temperature element disassembly device, including a stretching assembly and a knocking-off assembly; The lifting assembly includes a mounting block, a slider slidably connected to the mounting block, and a lead screw rotatably connected to the mounting block. The slider and the lead screw are threaded together. The slider is provided with an upper clamping plate for connecting a temperature element, and the mounting block is provided with a lower clamping plate for connecting a protective sleeve. The loosening assembly includes an upper end plate, a metal rod, a lower end plate, a slide rod, and a sliding hammer slidably connected to the slide rod in sequence; the upper end plate is located between the upper clamping plate and the temperature element; the protective sleeve is located between the upper end plate and the lower end plate.

[0006] Beneficial effects: 1. This device is equipped with a tensioning assembly that uses an upper clamping plate to hold the temperature element and a lower clamping plate to hold the protective sleeve. The slider is driven by a lead screw to move axially, thereby outputting a smooth axial release force to the temperature element and the protective sleeve. This not only ensures that the temperature element and the protective sleeve can be stably pulled axially, preventing the temperature element from breaking due to eccentric force, but also eliminates some of the expansion force of the bellows in advance, reducing the resistance when the temperature element is pulled out of the protective sleeve, making it easier for the temperature element to be removed from the protective sleeve and improving disassembly efficiency.

[0007] 2. This device first applies an initial axial tensile force to the temperature element and protective sleeve through the upper and lower clamping plates to reduce the expansion resistance of the bellows in the temperature element. Then, the sliding hammer of the loosening assembly strikes the lower end plate. The impact force generated by the strike is transmitted through the lower end plate to the metal rod, the upper end plate, and finally to the temperature element, loosening it. Then, the screw is rotated to drive the slider to move axially, and the upper clamping plate on the slider can gradually pull out the temperature element. Compared with the existing technology that relies entirely on the impact force of the strike, this solution uses the strike as an auxiliary means. The subsequent pull-out operation of the temperature element is completed by the controllable and stable axial tensile force provided by the screw and slider. Throughout the process, the force is kept as far along the axial direction of the temperature element as possible, reducing lateral load and significantly reducing the risk of the temperature element breaking and being scrapped due to the oblique force, thus improving the disassembly success rate and reducing the scrap rate.

[0008] Furthermore, the mounting block is provided with a groove, and the lead screw is rotatably connected in the groove. One end of the lead screw extends out of the groove and is fixed with a hexagonal head.

[0009] Beneficial effects: The end of the lead screw extends out of the groove and is equipped with a hexagonal head, which can be turned with standard tools such as torque wrenches to facilitate control of the lead screw's rotation torque, achieve controllable application of axial tension, and facilitate operation by workers.

[0010] Furthermore, a sliding groove is provided in the groove of the mounting block, and one end of the slider is slidably connected in the sliding groove.

[0011] Beneficial effects: The groove guides and constrains the slider, which moves in a straight line along the groove. This restricts the slider from radial deflection and ensures that it can only move axially. This prevents the slider from tilting under load, thus ensuring that the pulling force output by the upper plate is always along the axial direction of the temperature element, preventing the generation of lateral force and reducing the risk of bending and breaking of the temperature element.

[0012] Furthermore, both the upper and lower card plates are provided with U-shaped card slots.

[0013] Beneficial effects: The U-shaped slot has an open bayonet structure, which can be easily snapped onto the outer periphery of the temperature element and the protective sleeve. Assembly and disassembly are convenient. At the same time, the U-shaped slot can form a clamping limit for the temperature element and the protective sleeve, ensuring reliable clamping and positioning. It is not easy to slip off during operation, ensuring that the tensile force can be effectively transmitted.

[0014] Furthermore, the upper plate is provided with a U-shaped slot.

[0015] Beneficial effects: The upper plate adopts a U-shaped open slot, which can be quickly snapped onto the outside of the temperature element from the side without having to fit it through the end of the element. This makes it easy to loosen the component and install it directly after the stretching assembly is completed, simplifying the on-site assembly process.

[0016] Furthermore, the end of the slide rod is connected to the lower end plate by a thread, and a baffle is fixed to the other end of the slide rod, the diameter of which is larger than the diameter of the slide rod.

[0017] Beneficial effects: A large-diameter baffle is installed at the end of the slide bar to limit and block the sliding hammer, preventing it from detaching and flying out from the end of the slide bar during the striking operation. The slide bar and the lower end plate are connected by threads, which makes disassembly and assembly convenient and facilitates the inspection and replacement of parts. Attached Figure Description

[0018] Figure 1 This is a front view of the structure of the stretching component and the knocking component of the present invention.

[0019] Figure 2 for Figure 1 Front view of the medium temperature element and protective sleeve after disassembly and removal.

[0020] Figure 3 for Figure 1 Axonometric view of the loosened component.

[0021] Figure 4 for Figure 3 The front view of the loosened component. Detailed Implementation

[0022] The following detailed description illustrates the specific implementation method: The markings in the accompanying drawings include: mounting block 1, lead screw 2, hexagonal head 3, temperature element 4, slider 5, upper nut 6, upper end plate 7, upper clamping plate 8, lower clamping plate 9, protective sleeve 10, lower end plate 11, sliding hammer 12, baffle 13, bellows 14, lower nut 15, metal rod 16, sliding rod 17, and locking nut 18.

[0023] Example 1 like Figures 1 to 4 As shown, the power plant nuclear-grade temperature element 4 disassembly device includes a stretching assembly and a knocking assembly; the stretching assembly and the knocking assembly can be installed onto the temperature element 4 and the protective sleeve 10. Figure 2 As shown, Figure 2 The temperature element 4 and the protective sleeve 10 are in the state after being disassembled. The temperature element 4 is provided with an upper nut 6, and below the upper nut 6 is a bellows 14. The protective sleeve 10 is provided with a lower nut 15.

[0024] like Figure 1 As shown, the lifting assembly includes a mounting block 1, a slider 5 slidably connected to the mounting block 1, and a lead screw 2 rotatably connected to the mounting block 1. The mounting block 1 has a groove, and the lead screw 2 is rotatably connected within the groove. One end of the lead screw 2 extends out of the groove and is fixed with a hexagonal head 3. The rod of the lead screw 2 passes through the slider 5, and the slider 5 is threadedly connected to the lead screw 2. A sliding groove is also provided within the groove of the mounting block 1. Figure 1 The left end of the middle slider 5 is slidably connected in the slide groove. When the hexagonal head 3 is turned with a torque wrench, the lead screw 2 can be rotated, and the rotation of the lead screw 2 will drive the slider 5 to slide vertically along the slide groove on the mounting block 1. An upper clamping plate 8 is horizontally fixed at the right end of the slider 5, and a lower clamping plate 9 is horizontally fixed on the right side below the mounting block 1. Both the upper clamping plate 8 and the lower clamping plate 9 are provided with U-shaped grooves, so that the U-shaped groove of the upper clamping plate 8 can be inserted into the area below the upper nut 6 to achieve clamping and fixing with the temperature element 4, while the U-shaped groove of the lower clamping plate 9 can be inserted into the area below the lower nut 15 to achieve clamping and fixing with the protective sleeve 10.

[0025] like Figure 3 and Figure 4As shown, the loosening assembly includes an upper end plate 7, a metal rod 16, a lower end plate 11, a slide rod 17, and a sliding hammer 12 slidably connected to the slide rod 17, which are fixedly connected in sequence. The upper end plate 7 is provided with a U-shaped groove. In this embodiment, there are two metal rods 16, which are arranged parallel to each other on both sides of the U-shaped groove. The upper end of the slide rod 17 is connected to the lower end plate 11 by a thread and is locked by a locking nut 18. The lower end of the slide rod 17 is fixed with a baffle 13. The diameter of the baffle 13 is larger than the diameter of the slide rod 17, which is used to prevent the sliding hammer 12 from falling off the slide rod 17.

[0026] The method of using this device is as follows: like Figure 1 As shown, first, the protective sleeve 10 is snapped onto the lower clamping plate 9, so that the lower surface of the lower nut 15 presses against the upper surface of the lower clamping plate 9. The diameter of the U-shaped groove on the lower clamping plate 9 is smaller than the diameter of the lower nut 15, allowing the protective sleeve to hang on the lower clamping plate 9. The slider 5 is adjusted to leave a certain gap between the upper clamping plate 8 and the upper nut 6. Then, the upper end plate 7 is snapped into the gap area between the upper clamping plate 8 and the upper nut 6. Then, the slider 5 is adjusted to move upward so that the upper surface of the upper end plate 7 contacts the lower surface of the upper nut 6, and the protective sleeve 10 is in the area between the two metal rods 16. At this time, a torque wrench is used to tighten... Turn the hexagonal head 3 to a certain torque and then stop. Use the upper clamping plate 8 to move upward to apply a certain initial axial tension to the temperature element 4 and the protective sleeve 10, thereby reducing the expansion resistance of the bellows 14 in the temperature element 4. Then, use the sliding hammer 12 of the loosening assembly to strike the lower end plate 11 upward. The impact force generated by the strike is transmitted through the lower end plate 11 to the metal rod 16, the upper end plate 7, and finally to the temperature element 4, loosening the temperature element 4. Remove it, and then turn the hexagonal head 3 to drive the slider 5 to move upward. The upper clamping plate 8 can then gradually pull out the temperature element 4, realizing the convenient disassembly of the temperature element 4.

[0027] The above are merely embodiments of the present invention, and the invention is not limited to the fields covered by this embodiment. Commonly known structures and characteristics in the solutions are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the structure of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A nuclear power plant nuclear-grade temperature element disassembly device, characterized in that: Includes stretching components and knocking-out components; The lifting assembly includes a mounting block, a slider slidably connected to the mounting block, and a lead screw rotatably connected to the mounting block. The slider and the lead screw are threaded together. The slider is provided with an upper clamping plate for connecting a temperature element, and the mounting block is provided with a lower clamping plate for connecting a protective sleeve. The loosening assembly includes an upper end plate, a metal rod, a lower end plate, a slide rod, and a sliding hammer slidably connected to the slide rod in sequence; the upper end plate is located between the upper clamping plate and the temperature element; the protective sleeve is located between the upper end plate and the lower end plate.

2. The nuclear power plant nuclear-grade temperature element disassembly device according to claim 1, characterized in that: The mounting block has a groove, and the lead screw is rotatably connected in the groove. One end of the lead screw extends out of the groove and is fixed with a hexagonal head.

3. The nuclear power plant nuclear-grade temperature element disassembly device according to claim 2, characterized in that: The mounting block also has a groove, and one end of the slider is slidably connected in the groove.

4. The nuclear power plant nuclear-grade temperature element disassembly device according to claim 3, characterized in that: Both the upper and lower card plates are equipped with U-shaped card slots.

5. The nuclear power plant nuclear-grade temperature element disassembly device according to claim 4, characterized in that: The upper plate is provided with a U-shaped slot.

6. The nuclear power plant nuclear-grade temperature element disassembly device according to claim 5, characterized in that: The end of the slide rod is connected to the lower end plate by a thread, and the other end of the slide rod is fixed with a baffle plate, the diameter of which is larger than the diameter of the slide rod.

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