A smooth pipe orifice fastening connection device

Abstract

The present invention discloses a smooth pipe orifice fastening connection device, which sequentially includes a split positioning thread assembly, a transition connection wedge assembly (M), and an integral pressing thread assembly (C) from inside to outside; the transition connection wedge assembly (M) and the split positioning thread assembly are tightly locked through a hook wrench slot (G) on the integral pressing thread assembly (C); the integral pressing thread assembly limit ring locking bolt (H) restricts the axial displacement of the integral pressing thread assembly (C) by fixing the integral pressing thread assembly limit ring (D). The structure of the smooth pipe orifice fastening connection device is relatively simple, the disassembly and assembly process of the components is easy to operate, and there is no need to use lubricating reagents, reducing the items introduced into the IRWST water tank and reducing the foreign object risk; during the disassembly and assembly process of the components, there is no need to use hydraulic tools for hard installation and disassembly, which can well reduce the installation period of temporary test equipment compared with the existing scheme.

Description

Technical Field

[0001] The invention belongs to the field of commissioning of the core cooling system of passive nuclear power plant units, and particularly relates to the installation of an underwater pneumatic isolation device dedicated for the flow resistance test (related to nuclear safety) of the containment sump direct injection pipeline and the containment sump recirculation pipeline during the unit commissioning stage. Background Art

[0002] The passive core cooling system (hereinafter referred to as PXS) is a unique safety system of AP / CAP series nuclear power plants. Most of the flow channel tests of this system are to verify the dedicated safety functions of the power plant. The relevant tests are the main critical paths for the nuclear island commissioning tests to be carried out according to the plan, and are the key points and key aspects of the nuclear island commissioning. According to the requirements of the relevant documents on the test design of the PXS system of CAP series nuclear power plants, during the unit commissioning stage, it is necessary to conduct pipeline flow resistance measurement tests on the direct injection pipeline from the in-containment refueling water storage tank (hereinafter referred to as: IRWST) to the containment sump and the containment sump recirculation pipeline in the PXS system, so as to equivalently verify that the containment direct injection and the containment sump recirculation capabilities under severe accident conditions meet the nuclear power plant safety analysis and design requirements.

[0003] Based on the pipeline design structure of the PXS system of CAP series nuclear power plants, the inlet of the safety injection pipeline of the in-containment refueling water storage tank is a smooth pipe orifice, and there are no structural components on the pipe orifice that can install a pneumatic isolation device. In order to normally measure parameters such as the test flow rate of the containment sump direct injection pipeline and the containment sump recirculation pipeline, and prevent the relevant restrictions between different test pipelines, it is necessary to install and use a temporary pneumatic isolation device during the test to control the test medium and effectively and reliably isolate the non-test flow channels. Based on the engineering practice of applying the circular nested device and the transition connecting piece used for the installation of the temporary pneumatic isolation device in the existing flow channel test of the safety injection pipeline at the inlet of the IRWST water tank of the PXS system, according to the subsequent requirements of the flow channel test of the pipeline from the inlet pipeline of the IRWST water tank to the containment sump direct injection pipeline and the containment sump recirculation pipeline in the PXS system of CAP series nuclear power plants, a smooth pipe orifice fastening connection device that meets the requirements for the installation of the test pneumatic isolation device is independently developed and designed. Summary of the Invention

[0004] The invention aims to meet the reliable installation of engineering test equipment, is oriented to ensuring the safe operation of the equipment, and combines the actual test requirements to independently develop and design a smooth pipe orifice fastening connection device that meets the installation of the pneumatic isolation device used in the relevant flow channel tests of the safety injection pipeline at the inlet of the IRWST water tank of the subsequent PXS system of CAP series nuclear power plants. The following technical solutions are adopted: the device sequentially includes a split positioning thread assembly, a transition connection wedge assembly (M), and an integral pressing thread assembly (C) from inside to outside;

[0005] The split-type positioning thread assembly is such that the split-type positioning thread assembly positioning block (B) is positioned on the outer wall of the pipeline by the radially split-type positioning thread assembly positioning block fastening bolt (F);

[0006] The transition connection wedge-shaped assembly (M) is in wedge surface fit with the split-type positioning thread assembly and is fastened and locked through the hook wrench slot (G) on the integral compression thread assembly (C); there is a sliding clearance with a certain distance between the transition connection wedge-shaped assembly (M) and the integral compression thread assembly (C);

[0007] The outside of the integral compression thread assembly (C) is slidably nested with the integral compression thread assembly limiting ring (D), and the integral compression thread assembly limiting ring locking bolt (H) is arranged on the circumference of the integral compression thread assembly limiting ring (D). The integral compression thread assembly limiting ring locking bolt (H) restricts the axial displacement of the integral compression thread assembly (C) by fixing the integral compression thread assembly limiting ring (D).

[0008] Preferably, the integral compression thread assembly limiting ring locking bolt (H) is an internal hexagonal type.

[0009] Preferably, the inner surface of the split-type positioning thread assembly positioning block (B) is processed by diamond knurling.

[0010] Preferably, the outer side of the overlapping fit section of the split positioning thread assembly and the transition connection wedge-shaped assembly (M) is provided with locking threads, and the locking threads are in thread engagement with the integral compression thread assembly (C).

[0011] Preferably, the integral compression thread assembly (C) is a circular column with built-in locking threads.

[0012] Preferably, after the integral compression thread assembly (C) is assembled, a pneumatic isolation device interface flange (E) is welded.

[0013] Preferably, the pneumatic isolation device interface flange (E) is provided with a sealing positioning groove. The pneumatic isolation device interface flange (E) and the split-type positioning thread assembly cooperate to extrude a seal to achieve reliable sealing of the outer wall of the pipeline.

[0014] The smooth pipe orifice fastening connection device has a relatively simple structure, and the disassembly and assembly process of the components is easy to operate. Moreover, there is no need to use lubricating reagents, which reduces the items introduced into the IRWST water tank and lowers the foreign object risk. During the disassembly and assembly process of the components, there is no need to use hydraulic tools for forced installation and disassembly. Compared with the existing solutions, it can well reduce the installation period of the test temporary equipment. The inner wall of the split positioning thread component is processed by diamond knurling. After applying sufficient torque to the reinforcement bolt, it ensures that there is a large enough frictional force between the component and the pipeline, preventing axial sliding during the fastening process of the integral compression thread component and preventing equipment detachment caused by axial sliding during the operation of the pneumatic isolation device. Through the fastening of the integral compression thread component, the split positioning thread component and the transition connection wedge component have a sufficiently tight fit, ensuring reliable sealing and no leakage between each component and the pipeline, with high reliability. Description of the Drawings

[0015] Figure 1 It is a schematic diagram of a smooth pipe orifice fastening connection device;

[0016] Figure 2 It is an assembly drawing and a cross-sectional view of a smooth pipe orifice fastening connection device;

[0017] Figure 3 It is a solid structure diagram of the positioning block of the split positioning thread component;

[0018] Wherein: A - pipeline; B - positioning block of the split positioning thread component; C - integral compression thread component; D - limit ring of the integral compression thread component; E - flange of the pneumatic isolation device interface; F - fastening bolt of the positioning block of the split positioning thread component; G - hook wrench slot of the integral compression thread component; H - locking bolt of the limit ring of the integral compression thread component; I - seal; J - built-in locking thread; K - sliding gap of the limit ring of the integral compression thread component; L - bolt hole of the flange of the pneumatic isolation device interface; M - transition connection wedge component; N - straight flange of the interface of the positioning block of the split positioning thread component; O - knurled surface; P - seal installation groove; Q - bolt hole of the positioning block of the split positioning thread component. Detailed Embodiments

[0019] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0020] The following is a description of the structure of a smooth pipe orifice fastening connection device in combination with Figure 1 、 2 to further illustrate the present invention.

[0021] The first part is the split-type positioning thread assembly, which consists of two split-type positioning thread assembly positioning blocks B with the same structure and is connected through the paired pneumatic isolation device interface flange E. A certain tensile margin is designed between the pneumatic isolation device interface flanges E. During installation, it is tightened and stretched through the split-type positioning thread assembly positioning block fastening bolt F. The inner wall is formed with a knurled surface O through knurling to increase the friction coefficient with the outer wall of the pipeline. According to the locking torque of the split-type positioning thread assembly positioning block fastening bolt F, the cooperation degree between the inner wall of the assembly and the outer wall of the pipeline is strengthened, preventing axial sliding of the assembly during the locking process of the integral compression thread assembly C and also preventing axial displacement of the pipeline during the operation of the pneumatic isolation device, ensuring reliable positioning of the whole set of devices. This assembly provides a reliable installation sealing groove P for the outer wall seal I of the pipeline.

[0022] The second part is the transition connection wedge-shaped component M: This component forms an assembly with the integral compression thread assembly C, the integral compression thread assembly limit ring D, the pneumatic isolation device installation interface flange E, and the transition connection wedge-shaped component M. This component is manufactured by forging. First, the integral compression thread assembly C is nested and assembled, then the integral compression thread assembly limit ring D is assembled, and finally the pneumatic isolation device installation interface flange E is welded. Six hexagon socket head cap screws H for locking the integral compression thread assembly limit ring are distributed on the 360° circumference of the integral compression thread assembly limit ring D. When the integral compression thread assembly C locks the split-type positioning thread assembly, the integral compression thread assembly limit ring D is fixed through the six hexagon socket head cap screws H for locking the integral compression thread assembly limit ring, restricting the axial displacement of the integral compression thread assembly C. The transition connection wedge-shaped component M has its own sealing positioning groove. After installation, it cooperates with the split-type positioning thread assembly to squeeze the seal I, achieving reliable sealing of the outer wall of the pipeline.

[0023] The third part is the integral compression thread assembly C: The overall structure of this component is a circular column with an internal locking thread J. When the split-type positioning thread assembly cooperates with the transition connection wedge-shaped component M, a special hook wrench is used to apply torque through the card slot G, and the integral compression thread assembly C is rotated to fasten the split-type positioning thread assembly positioning block B to provide axial tension, increasing the cooperation degree between the split-type positioning thread assembly positioning block B and the transition connection wedge-shaped component M, ensuring reliable sealing of the outer wall of the pipeline. It provides reliable positioning for the transition connection wedge-shaped component M, facilitating the installation and cooperation of the pneumatic isolation device interface flange E.

[0024] The above process configures the split-type positioning thread assembly, the transition connection wedge-shaped component, the integral compression thread assembly, and the integral compression thread assembly limit ring, etc. Before installing the test special pneumatic isolation device, first assemble the above components, and then hoist and install the pneumatic isolation device and assemble it with the interface flange carried by the transition connection wedge-shaped component to complete the assembly of the test special pneumatic isolation device.

[0025] Obviously, those skilled in the art can make various modifications and variations to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations to the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention is also intended to include these modifications and variations. The above embodiments or implementation manners are only illustrative examples of the present invention, and the present invention can also be implemented in other specific ways or other specific forms without departing from the gist or essential features of the present invention. Therefore, the described implementation manners should be regarded as illustrative rather than restrictive in any aspect. The scope of the present invention shall be defined by the appended claims, and any changes equivalent to the intention and scope of the claims should also be included within the scope of the present invention.

Claims

1. A smooth pipe orifice fastening connection device, characterized in that, the device successively includes a split-type positioning thread assembly, a transition connection wedge-shaped assembly (M), and an integral pressing thread assembly (C) from inside to outside; the split-type positioning thread assembly is that split-type positioning thread assembly positioning blocks (B) are positioned on the outer wall of the pipeline through radially split-type positioning thread assembly positioning block fastening bolts (F), and the split-type positioning thread assembly provides a sealing installation groove (P) for the outer wall sealing of the pipeline; the transition connection wedge-shaped assembly (M) is in wedge surface fit with the split-type positioning thread assembly and is fastened and locked through a hook wrench slot (G) on the integral pressing thread assembly (C); there is a sliding gap with a certain distance between the transition connection wedge-shaped assembly (M) and the integral pressing thread assembly (C), and the transition connection wedge-shaped assembly (M) has a self-sealing positioning groove, and after installation, it cooperates with the split-type positioning thread assembly to extrude a seal (I) to achieve reliable sealing of the outer wall of the pipeline; the outside of the integral pressing thread assembly (C) is slidably nested with the integral pressing thread assembly limiting ring (D), and integral pressing thread assembly limiting ring locking bolts (H) are arranged on the circumference of the integral pressing thread assembly limiting ring (D), and the integral pressing thread assembly limiting ring locking bolts (H) limit the axial displacement of the integral pressing thread assembly (C) by fixing the integral pressing thread assembly limiting ring (D); the outer side of the overlapping and mating section of the split positioning thread assembly and the transition connection wedge-shaped assembly (M) is provided with locking threads, and the locking threads are in thread engagement with the integral pressing thread assembly (C); the integral pressing thread assembly (C) is a circular column with an internal locking thread (J).

2. A smooth pipe orifice fastening connection device according to claim 1, characterized in that, the integral pressing thread assembly limiting ring locking bolt (H) is an internal hexagonal type.

3. A smooth pipe orifice fastening connection device according to claim 1, characterized in that, the inner surface of the split-type positioning thread assembly positioning block (B) is processed by diamond knurling.

4. A smooth pipe orifice fastening connection device according to claim 1, characterized in that, after the integral pressing thread assembly (C) is assembled, a pneumatic isolation device interface flange (E) is welded.

5. A smooth pipe orifice fastening connection device according to claim 4, characterized in that, the pneumatic isolation device interface flange (E) and the split-type positioning thread assembly pass through a cooperating extrusion seal (I) to achieve reliable sealing of the outer wall of the pipeline.

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