A reactor sealing device for sealing and limiting cluster detector assemblies.

Abstract

This invention belongs to the field of reactor structure technology, specifically relating to a reactor sealing device for sealing and limiting a clustered detector assembly. It includes an axial limiting structure and a sealing structure. The axial fiber structure is disposed on a grooved section of the detector assembly to achieve axial limiting of the detector assembly, and the sealing structure is disposed between the detector assembly and the plug to achieve a seal between the detector assembly and the plug. The beneficial effect is that by utilizing the grooved section at the top of the detector assembly, an axial limiting structure composed of a nut, an upper pressure ring, a lower pressure ring, a support rod, a support sleeve, and a limiting half-ring is provided, achieving axial limiting of the detector assembly and preventing the detector assembly from being ejected due to coolant pressure during reactor operation.

Description

Technical Field

[0001] This invention belongs to the field of reactor structure technology, specifically relating to a reactor sealing device for sealing and limiting cluster detector components. Background Technology

[0002] The reactor core measurement detector assembly of a nuclear power plant reactor structure consists of dozens of detectors. These detectors are bundled together and pass through the top cover of the reactor pressure vessel. The bundled detector assembly is then sealed on the top cover of the pressure vessel to prevent coolant leakage. The sealing method generally involves installing a plug on the measuring tube seat on the top cover of the reactor pressure vessel, and installing a sealing device for the measuring tube seat and the plug. At the same time, another set of sealing devices is installed for the bundled detector assembly and the plug.

[0003] For sealing devices used in plugs and clustered detector assemblies, it is necessary not only to seal the coolant at the point where the detector assembly exits the plug, but also to withstand the internal pressure force exerted by the detector assembly pushing outward axially during reactor operation. Current nuclear power plants typically use compression fittings installed on the plugs. By tightening the conical metal ring inside the fitting, the detector assembly is sealed and axially limited. However, when the fitting is tightened, the conical metal ring can deform the metal casing of the detector assembly, causing some damage. Summary of the Invention

[0004] The purpose of this invention is to provide a reactor sealing device for sealing and limiting clustered detector assemblies, which does not damage the detector housing and has good sealing performance.

[0005] The technical solution of the present invention is as follows: a reactor sealing device for sealing and limiting a clustered detector assembly, comprising an axial limiting structure and a sealing structure, wherein the axial fiber structure is disposed on the groove section of the detector assembly to achieve axial limiting of the detector assembly, and the sealing structure is disposed between the detector assembly and the plug to achieve sealing between the detector assembly and the plug.

[0006] The axial limiting structure includes a nut, an upper pressure ring, a limiting half-ring, a lower pressure ring, a support rod, and a support sleeve. The support rod is installed above the plug and is used to install the upper pressure ring, the lower pressure ring, and the limiting half-ring. The nut engages with the top of the support rod to press the upper pressure ring and the limiting half-ring. The support sleeve is installed on the outside of the support rod, the lower pressure ring is installed on the support sleeve, and the upper pressure ring is installed above the lower pressure ring. The limiting half-ring assembly is pressed together by the upper pressure ring and the lower pressure ring.

[0007] The limiting semi-ring assembly includes two limiting semi-rings, which are engaged in the groove section of the detector assembly.

[0008] The support sleeve is a columnar structure with a through hole in the middle and a petal-shaped support surface at the top. The petal-shaped support surface is used to limit the axial downward displacement of the detector assembly.

[0009] The sealing structure includes a hollow bolt, an upper anti-rotation ring, a small graphite ring, and a gasket; the upper anti-rotation ring, the small graphite ring, and the gasket are installed between the detector assembly and the plug, and the hollow bolt and the plug cooperate to press the small graphite ring, filling the gap between the plug and the detector assembly.

[0010] The hollow bolt has a through hole in the middle and threads on the outside, which are used to engage with the internal threads of the plug to press the small graphite ring; the washer ring supports the small graphite ring, and the upper anti-rotation ring is installed between the small graphite ring and the hollow bolt.

[0011] The small graphite rings are filled between the detector and the plug, with flexible graphite as the sealing and filling medium.

[0012] The beneficial effects of this invention are as follows: An axial limiting structure, consisting of a nut, upper pressure ring, lower pressure ring, support rod, support sleeve, and limiting half-ring, is set up in the grooved section at the top of the detector assembly. This achieves axial limiting of the detector assembly, preventing it from being ejected by the coolant pressure inside the reactor during reactor operation. Using the grooved section at the top of the detector assembly to achieve axial limiting avoids modifying the original structure of the detector assembly and avoids the limiting method of using a compression fitting to squeeze the metal shell of the detector assembly, which can cause deformation and damage. A small graphite ring is filled between the detector assembly and the plug, replacing the line seal of the compression fitting metal ring with a surface seal of the graphite ring, resulting in a better sealing effect. Attached Figure Description

[0013] Figure 1 This is a schematic diagram of a reactor sealing device for sealing and limiting cluster detector components provided by the present invention.

[0014] Figure 2 yes Figure 1 AA section view;

[0015] Figure 3 yes Figure 1 BB cross-sectional view;

[0016] Figure 4 yes Figure 1 A magnified C view;

[0017] Figure 5 It is the petal-shaped support surface of the support sleeve.

[0018] In the diagram: 1 Nut, 2 Upper pressure ring, 3 Limiting half ring, 4 Lower pressure ring, 5 Support rod, 6 Hollow bolt, 7 Upper anti-rotation ring, 8 Small graphite ring, 9 Washer ring, 10 Support sleeve, 11 Detector assembly, 12 Plug, 13 Limiting groove section, 14 Petal-shaped support surface, 15 Sealing section. Detailed Implementation

[0019] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0020] like Figure 1 As shown, the reactor sealing device provided by the present invention is used to seal and limit the multiple detector assemblies 11 bundled together in a plug 12, thereby achieving sealing and axial limiting. The present invention consists of two parts: an axial limiting structure and a sealing structure. Multiple detector assemblies 11 (four in this embodiment) are inserted into the inner hole of the plug 12 and are evenly distributed circumferentially. The axial limiting structure includes a nut 1, an upper pressure ring 2, a limiting half-ring 3, a lower pressure ring 4, a support rod 5, and a support sleeve 10; the sealing structure includes a hollow bolt 6, an upper anti-rotation ring 7, a small graphite ring 8, and a washer 9.

[0021] The support rod 5 is threadedly installed above the plug 12 and is used to install the upper pressure ring 2, the lower pressure ring 4, and the limiting half-ring 3. The support sleeve 10 is installed on the outside of the support rod 5 and is used to determine the axial position of the detector assembly 11 when it is inserted into the plug 12. The lower pressure ring 4 is installed on the support sleeve 10, and the upper pressure ring 2 is installed above the lower pressure ring 4. The upper pressure ring 2 and the lower pressure ring 4 press the four sets of limiting half-rings together. Each set of limiting half-rings consists of two limiting half-rings 3. The two limiting half-rings 3 are engaged in the groove section 13 of the detector assembly. The nut 1 is threadedly engaged with the top of the support rod 5 to press the upper pressure ring 2 and the limiting half-rings 3 together, thereby achieving axial limiting of the four detector assemblies and preventing the detector assembly 11 from being ejected by the coolant pressure inside the reactor during reactor operation.

[0022] The axial limiting of the detector assembly 11 is achieved by using the groove section 13 on the top of the detector assembly 11. This does not modify the original structure of the detector assembly 11 or affect the structure of the detector sealing surface 15, and has wide applicability.

[0023] like Figure 1 and Figure 2 As shown, the two limiting semi-rings 3 are engaged in the groove section 13 of the detector assembly 11. The nut 1 and the top of the support rod 5 are threaded together to press the upper pressure ring 2 and the limiting semi-rings 3, thereby achieving axial limiting of the four detector assemblies 11.

[0024] like Figure 3 and 5As shown, the support sleeve 10 is a columnar structure with a through hole in the middle and a petal-shaped support surface 14 at one end. The petal-shaped support surface 14 is used to limit the axial downward displacement of the detector assembly 11, which facilitates the axial positioning of the detector assembly 11 during initial installation. After installing the upper pressure ring 2, the lower pressure ring 4 and the limiting half ring 3, the support sleeve 10 is rotated. At this time, the petal-shaped support surface 14 of the support sleeve 10 is misaligned with the detector assembly 11, and the petal-shaped support surface 14 no longer plays the role of axial support and limiting. The upper pressure ring 2, the lower pressure ring 4 and the limiting half ring 3 provide axial limiting.

[0025] like Figure 4 As shown, the upper anti-rotation ring 7, the small graphite ring 8, and the washer ring 9 are installed between the detector assembly 11 and the plug 12. The hollow bolt 6 and the plug 12 cooperate to press the small graphite ring 8, filling the gap between the plug 12 and the detector assembly 11, preventing coolant leakage from the gap, and achieving a seal between the detector assembly 11 and the plug 12. The hollow bolt 6 has a through hole in the middle for passing through the detector assembly 11. The hollow bolt 6 has threads on the outside for engaging with the internal threads of the plug 12 to provide preload and press the small graphite ring 8. The washer ring 9 is used to support the small graphite ring 8. The upper anti-rotation ring 7 is installed between the small graphite ring 8 and the hollow bolt 6, serving as an intermediate transition for the hollow bolt 6 to press the small graphite ring 8, preventing the small graphite ring 8 from rotating with the hollow bolt 6, and avoiding damage to the side sealing surface of the small graphite ring 8. The upper end of the small graphite ring 8 is an upper anti-rotation ring 7, and the lower end is a washer ring 9. The washer ring 9 is used to support the small graphite ring 8, and the upper anti-rotation ring 7 is used to prevent the bottom of the hollow bolt 6 from scraping against the small graphite ring 8 when it rotates, thus preventing wear on the small graphite ring 8.

[0026] Small graphite rings 8 are filled between the detector 11 and the plug 12. Flexible graphite is used as the sealing and filling medium, which will not cause compression damage to the detector assembly 11, which is harder.

[0027] The above embodiments are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any changes made based on the design principles of the present invention, or any non-creative modifications made thereon, shall fall within the scope of protection of the present invention.

Claims

1. A reactor sealing device for sealing and limiting a cluster detector assembly, characterized in that: It includes an axial limiting structure and a sealing structure. The axial limiting structure is set on the groove section of the detector assembly to limit the axial movement of the detector assembly. The sealing structure is set between the detector assembly and the plug to seal the detector assembly and the plug. The axial limiting structure includes a nut, an upper pressure ring, a limiting half-ring assembly, a lower pressure ring, a support rod, and a support sleeve. The support rod is installed above the plug and is used to install the upper pressure ring, the lower pressure ring, and the limiting half-ring assembly. The nut engages with the top of the support rod to press the upper pressure ring and the limiting half-ring assembly. The support sleeve is installed on the outside of the support rod, the lower pressure ring is installed on the support sleeve, and the upper pressure ring is installed above the lower pressure ring. The upper and lower pressure rings press the limiting half-ring assembly together. The limiting semi-ring assembly includes two limiting semi-rings, which are engaged in the groove section of the detector assembly. The sealing structure includes a hollow bolt, an upper anti-rotation ring, a small graphite ring, and a gasket. The upper anti-rotation ring, the small graphite ring, and the gasket are installed between the detector assembly and the plug. The gasket supports the small graphite ring, and the upper anti-rotation ring is installed between the small graphite ring and the hollow bolt. The hollow bolt and the plug cooperate to press the small graphite ring, filling the gap between the plug and the detector assembly.

2. The reactor sealing device for sealing and limiting a cluster detector assembly as described in claim 1, characterized in that: The support sleeve is a columnar structure with a through hole in the middle and a petal-shaped support surface at the top. The petal-shaped support surface is used to limit the axial downward displacement of the detector assembly.

3. The reactor sealing device for sealing and limiting cluster detector components as described in claim 1, characterized in that: The hollow bolt has a through hole in the middle and threads on the outside, which are used to engage with the internal threads of the plug to press the small graphite ring.

4. The reactor sealing device for sealing and limiting a cluster detector assembly as described in claim 1, characterized in that: The small graphite rings are filled between the detector and the plug, with flexible graphite as the sealing and filling medium.

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