Reactor sealing device for sealing and limiting clustered detector assembly

Abstract

The invention belongs to the technical field of reactor structures, and particularly relates to a reactor sealing device for sealing and limiting a clustered detector assembly. Comprising an axial limiting structure and a sealing structure, the axial fiber structure is arranged on the groove section of the detector assembly to achieve axial limiting of the detector assembly, and the sealing structure is arranged between the detector assembly and the plug to achieve sealing between the detector assembly and the plug. The device has the beneficial effects that the axial limiting structure consisting of the nut, the upper pressing ring, the lower pressing ring, the supporting rod, the supporting sleeve and the limiting semi-ring is arranged by utilizing the groove section at the top of the detector assembly, so that the axial limiting of the detector assembly is realized, and the detector assembly is prevented from being popped out under the pressure of a coolant in a reactor when the reactor runs.

Description

Technical Field

[0001] The invention belongs to the technical field of reactor structures, and in particular relates to a reactor sealing device for sealing and limiting a cluster detector assembly. Background Art

[0002] There are dozens of detector assemblies for core measurement in the reactor structure of a nuclear power plant. Multiple detector assemblies are bundled together and passed through the top cover of the reactor pressure vessel. The bundled detector assemblies are sealed on the top cover of the pressure vessel to prevent coolant leakage. The sealing method generally adopts a method of providing a plug on the measuring tube seat of the top cover of the reactor pressure vessel, providing a sealing device for the measuring tube seat and the plug, and providing another set of sealing devices for the clustered detector assembly and the plug.

[0003] The sealing device for the plug and cluster detector assembly not only needs to achieve the coolant sealing at the part where the detector assembly passes through the plug, but also needs to withstand the internal pressure force of the detector assembly pushing outward along the axial direction when the reactor is running. At present, nuclear power plants usually install a ferrule-type pipe joint on the plug, and achieve the sealing and axial limitation of the detector assembly by tightening the conical metal ring inside the pipe joint. However, when the pipe joint is tightened, the metal shell of the detector assembly will be squeezed and deformed through the conical metal ring, causing certain damage to the metal shell of the detector assembly. Summary of the invention

[0004] The object of the present invention is to provide a reactor sealing device for sealing and limiting a cluster detector assembly, which will 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 arranged on the groove section of the detector assembly to achieve axial limiting of the detector assembly, and the sealing structure is arranged 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 cooperates 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, the upper pressure ring is installed above the lower pressure ring, and the limiting half ring assembly is pressed by the upper pressure ring and the lower pressure ring.

[0007] The limiting half ring assembly comprises two limiting half rings, and the two limiting half rings are clamped 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 compress the small graphite ring to fill the gap between the plug and the detector assembly.

[0010] The hollow bolt has a through hole in the middle and a thread on the outside for cooperating with the internal thread of the plug to compress the small graphite ring; the gasket 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 ring is filled between the detector and the plug, with flexible graphite serving as a sealing filling medium.

[0012] The beneficial effects of the present invention are as follows: by utilizing the groove section at the top of the detector assembly, an axial limiting structure consisting of a nut, an upper pressure ring, a lower pressure ring, a support rod, a support sleeve and a limiting half ring is set, thereby realizing the axial limiting of the detector assembly and preventing the detector assembly from being ejected by the coolant pressure in the reactor when the reactor is running; by utilizing the groove section at the top of the detector assembly to realize the axial limiting of the detector assembly, the original structural form of the detector assembly is neither modified nor a limiting method in which a ferrule-type pipe joint is used to squeeze the metal shell of the detector assembly, thereby causing deformation and damage to the shell of the detector assembly; a small graphite ring is filled between the detector assembly and the plug, and the surface seal of the graphite ring replaces the line seal of the ferrule-type metal ring, thereby achieving a better sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic diagram of a reactor sealing device for sealing and limiting a cluster detector assembly 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 Enlarged C view of;

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

[0018] In the figure: 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 gasket, 10 support sleeve, 11 detector assembly, 12 plug, 13 limiting groove section, 14 petal-shaped support surface, 15 sealing section. DETAILED DESCRIPTION

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

[0020] like Figure 1 As shown, a reactor sealing device for sealing and limiting a clustered detector assembly provided by the present invention is used to achieve sealing and axial limiting of multiple detector assemblies 11 that are bundled together in a plug 12. The present invention is divided into two parts: an axial limiting structure and a sealing structure. Multiple (four in this embodiment) detector assemblies 11 are inserted into the inner hole of the plug 12 and are evenly distributed along the circumference. 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 gasket 9.

[0021] Among them, the support rod 5 is installed above the plug 12 through threads, 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 when the detector assembly 11 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 four sets of limiting half rings are compressed by the upper pressure ring 2 and the lower pressure ring 4, and each set of limiting half rings is composed of two limiting half rings 3. The two limiting half rings 3 are stuck in the groove section 13 of the detector assembly, and the nut 1 is threadedly matched with the top of the support rod 5 to compress the upper pressure ring 2 and the limiting half ring 3, so as to realize the axial limitation of the four detector assemblies, and prevent the detector assembly 11 from being ejected by the coolant pressure in the reactor when the reactor is running.

[0022] The axial limiting of the detector assembly 11 is achieved by using the groove section 13 at the top of the detector assembly 11 , without modifying the original structure of the detector assembly 11 or affecting the structure of the detector sealing surface 15 , and has wide applicability.

[0023] like Figure 1 and Figure 2 As shown, two limiting half rings 3 are clamped on the groove section 13 of the detector assembly 11, and the nut 1 is threadedly matched with the top of the support rod 5 to press the upper pressure ring 2 and the limiting half ring 3, thereby realizing axial limitation of the four detector assemblies 11.

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

[0025] like Figure 4 As shown, the upper anti-rotation ring 7, the small graphite ring 8 and the gasket 9 are installed between the detector assembly 11 and the plug 12. The hollow bolt 6 and the plug 12 cooperate to compress the small graphite ring 8, fill the gap between the plug 12 and the detector assembly 11, prevent the coolant from leaking from the gap, and achieve the seal between the detector assembly 11 and the plug 12. A through hole is opened in the middle of the hollow bolt 6 for passing through the detector assembly 11. The outer surface of the hollow bolt 6 is threaded for cooperating with the internal thread of the plug 12 to provide a pre-tightening force and compress the small graphite ring 8; the gasket 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, and is used as an intermediate transition for the hollow bolt 6 to compress the small graphite ring 8, so as to prevent the small graphite ring 8 from rotating with the rotation of the hollow bolt 6 and avoid damaging 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 gasket ring 9. The gasket ring 9 is used to support the small graphite ring 8. The upper anti-rotation ring 7 is used to prevent the bottom of the hollow bolt 6 from scratching the small graphite ring 8 when rotating, causing wear of the small graphite ring 8.

[0026] The small graphite ring 8 is filled between the detector 11 and the plug 12, and the flexible graphite is used as the sealing filling medium, which will not cause extrusion damage to the detector component 11 which is harder than the hardness.

[0027] The above embodiments are only preferred embodiments of the present invention and are not intended to limit the protection scope of the present invention. Any changes made by adopting the design principles of the present invention and performing non-creative work on this basis should fall within the protection scope 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 fiber structure is arranged on the groove section of the detector assembly to realize axial limiting of the detector assembly. The sealing structure is arranged between the detector assembly and the plug to realize sealing between the detector assembly and the plug.

2. A reactor sealing device for sealing and limiting a cluster detector assembly according to claim 1, characterized in that: 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 cooperates 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, the upper pressure ring is installed above the lower pressure ring, and the limiting half ring assembly is pressed by the upper pressure ring and the lower pressure ring.

3. A reactor sealing device for sealing and limiting a cluster detector assembly as claimed in claim 2, characterized in that: The limiting half ring assembly comprises two limiting half rings, and the two limiting half rings are clamped in the groove section of the detector assembly.

4. A reactor sealing device for sealing and limiting a cluster detector assembly as claimed in claim 2, 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.

5. A reactor sealing device for sealing and limiting a cluster detector assembly according to claim 1, characterized in that: 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 compress the small graphite ring to fill the gap between the plug and the detector assembly.

6. A reactor sealing device for sealing and limiting a cluster detector assembly as claimed in claim 5, characterized in that: The hollow bolt has a through hole in the middle and a thread on the outside for cooperating with the internal thread of the plug to compress the small graphite ring; the gasket supports the small graphite ring, and the upper anti-rotation ring is installed between the small graphite ring and the hollow bolt.

7. A reactor sealing device for sealing and limiting a cluster detector assembly according to claim 5, characterized in that: The small graphite ring is filled between the detector and the plug, with flexible graphite serving as a sealing filling medium.

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