Irradiation sample hole plug

Abstract

The invention provides an irradiation sample hole plug. The irradiation sample hole plug comprises an upper barrel, a pin, an outer spring, an inner spring, a core rod, a connecting rod, a plug body and a check block. The check block is fixed to the plug body through a pin and can rotate around a pin shaft. And the upper cylinder body is arranged on the plug body through two pins. An outer spring is installed between the upper barrel and the plug body, and the upper barrel moves up and down in pin holes in the two sides of the plug body to compress the outer spring. And the inner spring is arranged in a gap between the core rod and the plug body. The core rod is connected with the connecting rod through a pin, the connecting rod is connected with the check block through a pin, and the check block is fixed with the plug body through a pin. The driving mode of the check block depends on the core rod and the connecting rod. By improving the structure of the hole plug, adopting mechanical self-locking, optimizing the structure and adopting a connecting rod type structure on the premise of not changing the original design, the anti-rushing function is added, so that the technical problem of how to reduce the problem that the irradiation sample hole plug is easy to be rushed out in the prior art is solved.

Description

Technical Field

[0001] The present application belongs to the field of nuclear power technology, and specifically relates to an irradiated sample hole plug. Background Art

[0002] An irradiation sample rack is provided on the hanging basket cylinder of the pressurized water reactor internals. The sample material placed in the irradiation sample rack is exactly the same as that of the reactor pressure vessel, so that it can be taken out for mechanical property testing at different stages during the reactor life. Accordingly, a hole is opened on the hanging basket flange corresponding to the position of the irradiation sample rack, so that the irradiation sample can be disassembled later using a special long rod tool. In order to avoid additional bypass flow, an irradiation sample hole plug is placed at the opening position to limit the bypass flow when the reactor is running.

[0003] In pressurized water reactors such as CNP600, CNP1000, and Hualong One, irradiation sample hole plugs are installed on the basket flange of the lower internals. Figure 1 and Figure 2 The irradiated sample hole plug for a pressurized water reactor (also known as a pressurized water reactor) consists of an upper end 1, an optical axis 2, a base 3 and a spring 4. The hole plug and the flange hole of the hanging basket are radially clear and axially unconstrained, and the upper end is the upper internal component of the reactor. During the refueling overhaul, after the upper internal component that compresses the irradiated sample hole plug is disassembled, there is no constraint component above the hole plug. When the reactor is undergoing a safety injection test or filling the reactor with water, that is, when water is flushed from the bottom of the hole plug, the hole plug is easily flushed out. Therefore, there is a possibility that the irradiated sample hole plug is flushed out by the primary coolant and randomly scattered in the reactor, which poses a great hidden danger.

[0004] At present, the irradiation sample hole plugs of pressurized water reactor nuclear power units all adopt this structure, including the CNP600, CNP1000, Hualong One and other reactor types, which are in urgent need of improvement.

[0005] For example, Patent 1 (application number 201910994798.9) discloses a wedge-shaped groove self-locking irradiation sample hole plug and its implementation method. However, the irradiation sample hole plug is not suitable for use in pressurized water reactor nuclear power units. The reason is that the wedge-shaped groove self-locking irradiation sample hole plug relies on the water flow impact pressure to generate self-locking, and the self-locking method is unreliable; the two ends of the irradiation sample hole plug extend out, which does not meet the hanging basket structure of the nuclear power unit. It is installed on the conical hanging basket, and the bottom of the hanging basket flange is not flat. The wedge-shaped groove self-locking irradiation sample hole plug is not suitable for use in current nuclear power units; the upper end of the wedge-shaped groove self-locking irradiation sample hole plug does not have elastic components such as springs, and is not suitable for use in the pile. Therefore, it is not used in the nuclear power industry.

[0006] Patent 2 (application number 201310311304.5) discloses a self-locking ball cone irradiation sample hole plug for pressurized water reactors. The ball cone irradiation sample hole plug is also not suitable for use in pressurized water reactor nuclear power units because the ball cone irradiation sample hole plug relies on the axial force generated by water flow impact, which is converted into horizontal tension through the wedge surface to generate friction between the hole wall and the friction force to prevent being flushed out. The design principle is unreliable and there is still a risk of flushing out. Considering that the technical reliability of relying on water flow impact to generate circumferential friction force cannot be verified, it has not been applied in engineering. It is not used in the nuclear power industry.

[0007] Patent 3 (application number 201910567106.2) discloses a limited irradiation sample hole plug and a locking method. The limited irradiation sample hole plug is also not suitable for use in pressurized water reactor nuclear power units. The reason is that the bottom of the hanging basket is a cone, not a plane, and the limited irradiation sample hole plug is not suitable for pressurized water reactor nuclear power units; the upper end of the limited irradiation sample hole plug does not have elastic components such as springs, and is not suitable for use in the reactor; the structure of the limited irradiation sample hole plug is complex, and it is unreliable to use in the reactor, and is not used in the nuclear power industry.

[0008] Therefore, how to reduce the problem of the hole plugs of irradiated samples being easily flushed out has become a technical problem that needs to be solved urgently. Summary of the invention

[0009] In view of this, the embodiment of the present application is committed to providing an irradiated sample hole plug, by improving the hole plug structure, adopting mechanical self-locking, optimizing the structure without changing the original design, adopting a connecting rod structure, and adding an anti-blowout function, in order to solve the problem of how to reduce the easy blowout of the irradiated sample hole plug in the prior art, which has become a technical problem that needs to be solved urgently.

[0010] The present application provides an irradiated sample hole plug, which includes an upper cylinder, a pin, an outer spring, an inner spring, a core rod, a connecting rod, a plug body and a stopper. The stopper is fixed to the plug body by a pin and is configured to rotate around a pin shaft. The upper cylinder is mounted on the plug body by two pins. An outer spring is installed between the upper cylinder and the plug body, and the upper cylinder compresses the outer spring by moving up and down in the pin holes on both sides of the plug body. The inner spring is arranged in the gap between the core rod and the plug body. The core rod is connected to the connecting rod by a pin, the connecting rod is connected to the stopper by a pin, and the stopper is fixed to the plug body by a pin. The drive mode of the stopper is based on the core rod and the connecting rod. When the core rod is in the upper position, the connecting rod drives the stopper to rotate clockwise around the pin shaft and retract into the plug body; when the core rod is in the lower position, the connecting rod drives the stopper to rotate counterclockwise around the pin shaft, and the stopper extends out of the outer surface of the plug body, axially interfering with the flange surface of the upper component to achieve self-locking.

[0011] In a specific embodiment of the present application, the thickness of the irradiation sample hole plug is greater than the thickness of the hanging basket flange.

[0012] In a specific embodiment of the present application, the lower end of the plug body is in a cone shape.

[0013] In a specific embodiment of the present application, the irradiated sample hole plug further comprises a grabbing operation sleeve which is threadedly connected to the core rod and installed at the center of the plug body to act as a driving stopper.

[0014] In a specific embodiment of the present application, the grabbing operation sleeve is cylindrical, and a plurality of gaps are evenly arranged in the circumferential direction.

[0015] In a specific embodiment of the present application, the irradiated sample hole plug further includes an end cap which is fixed to the plug body by threads.

[0016] The beneficial effects of the technical solution of the present application are: without changing the original design function of the irradiated sample hole plug, it adapts to the existing hanging basket structure and installation interface, improves the hole plug structure, adds an anti-blowout function, and adopts an actively locked mechanical structure and a connecting rod structure to achieve the anti-blowout function. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is a schematic diagram of the structure of an irradiated sample hole plug for a pressurized water reactor.

[0018] Figure 2 Shown Figure 1 Schematic diagram of the usage status of the irradiated sample hole plug for a pressurized water reactor shown.

[0019] Figure 3 Shown is a schematic structural diagram of an irradiated sample hole plug provided in one embodiment of the present application.

[0020] Figure 4 Shown Figure 3 A schematic cross-sectional view of the irradiated sample hole plug when the stopper is extended is shown.

[0021] Figure 5 Shown Figure 3 A schematic cross-sectional view of the irradiated sample hole plug when the stopper is retracted is shown.

[0022] Figure 6 Shown is an appearance diagram of an irradiated sample hole plug provided in one embodiment of the present application.

[0023] Figure 7 Shown Figure 3 The irradiated sample plugs and Figure 1 The comparison diagram of the installation of irradiated sample hole plugs for pressurized water reactors is shown.

[0024] Figure 8 Shown Figure 3 Installation diagram of the irradiated sample hole plug when the stopper is retracted.

[0025] Fig. 9 Shown Figure 3 Installation diagram of the irradiated sample hole plug with the stopper extended.

[0026] Fig.10 Shown Figure 3 The schematic diagram of the structure of the connecting rod slider mechanism in the irradiated sample hole plug is shown. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0028] At least one embodiment of the present application provides an irradiated sample hole plug, referring to Figures 3 to 10 The irradiated sample hole plug 11 includes an upper cylinder 1, a pin 2, an outer spring 3, an inner spring 4, a core rod 5, a connecting rod 6, a plug body 7 and a stopper 10. The stopper 10 is fixed to the plug body 7 by the pin 2 and is configured to rotate around the pin shaft. The upper cylinder 1 is mounted on the plug body 7 by two pins 2. An outer spring 3 is installed between the upper cylinder 1 and the plug body 7, and the upper cylinder 1 compresses the outer spring 3 by moving up and down in the pin holes on both sides of the plug body 7. The inner spring 4 is arranged in the gap between the core rod 5 and the plug body 7. The core rod 5 is connected to the connecting rod 6 by the pin 2, the connecting rod 6 is connected to the stopper 10 by the pin 2, and the stopper 10 is fixed to the plug body 7 by the pin 2. The drive mode of the stopper 10 relies on the core rod 5 and the connecting rod 6. When the core rod 5 is in the upper position, the connecting rod 6 drives the stopper 10 to rotate clockwise around the pin shaft and is retracted into the plug body 7; when the core rod 5 is in the lower position, the connecting rod 6 drives the stopper 10 to rotate counterclockwise around the pin shaft, and the stopper 10 extends out of the outer surface of the plug body 7, forming axial interference with the flange surface of the upper component to achieve self-locking.

[0029] It should be noted that the irradiated sample hole plug 11 is a connecting rod type anti-blowout structure hole plug. The plug body 7 is the structural main body of the entire irradiated sample hole plug 11, providing a structural framework for other components. The stopper 10 can rotate around the fixed pin. When the core rod 5 is lifted up, the stopper 10 is driven to rotate through the connecting rod 6, so that the stopper 10 is retracted into the plug body 7, and the irradiated sample hole plug 11 can be taken out by continuing to extract upward.

[0030] According to the technical solution provided in the embodiment of the present application, by arranging the core rod 5, the connecting rod 6, the plug body 7 and the stopper 10 components in the irradiated sample hole plug 11, it is achieved that in a natural state, relying on the compression elastic force of the inner spring 4 and the gravity of the core rod 5, the stopper 10 is laid flat through the connecting rod 6, and the stopper 10 protrudes from the outer cylinder surface of the plug body 7, and the hole plug is prevented from being rushed out by the limiting of the flange of the upper component. At the same time, after the stopper 10 is laid flat, it cannot continue to rotate downward due to the limitation of the spatial structure, and the force direction when the water flow impacts is also downward, which has the safety of structural design. At the same time, the double action of the inner spring of the core rod 5 and gravity is adopted to realize the extension of the stopper 10 in a natural state, protruding from the outer cylinder surface of the hole plug 11. In addition, by setting a stopper 10 in the irradiated sample hole plug 11, due to the limited space size under the flange surface of the hanging basket, there is only one stopper to adapt to the particularity of the structural size of the internal components of the pressurized water reactor nuclear power unit. Since one side of the flange surface of the internal component is a conical surface and the other side is a plane, the stopper can only act on the plane, so only one stopper is set, the structure is simple and can meet the self-locking requirements, and the use of the conical structure under the flange surface of the lower internal component of the nuclear power unit is realized, avoiding interference with the conical surface, and realizing the axial anti-burst effect. In addition, an external spring 3 is installed at the upper end of the irradiated sample hole plug 11, and the axial constraint of the irradiated sample hole plug 11 after being installed in the internal component of the pile is realized by using the external spring 3.

[0031] The embodiment of the present application adopts a special mechanical structure design to change the previous hole plug structure so that it has the function of preventing water from rushing out, thereby improving the operating reliability of the unit and reducing the risk of component falling off.

[0032] In at least one embodiment of the present application, the thickness of the irradiated sample hole plug 11 is greater than the thickness of the hanging basket flange. Figure 7 The original hole plug 20 is shorter in length and is installed in the mounting hole of the hanging basket flange 30 without axial constraint with the flange hole. The irradiated sample hole plug 11 is longer in length. The upper end of the irradiated sample hole plug 11 can be seated on the hanging basket flange 30, and the lower end of the irradiated sample hole plug 11 can pass through the entire thickness of the hanging basket flange. The stopper 10 is stretched out to protrude from the outer cylinder surface of the plug body 7 and rest under the hanging basket flange, further preventing water from rushing out.

[0033] In the natural state, the upper cylinder 1 is bounced up. After the irradiated sample hole plug 11 is installed, the upper internal component 40 compresses the outer spring 3 downward through the upper cylinder 1, which plays a role in axial positioning of the hole plug to prevent the hole plug from moving up and down when impacted by water flow.

[0034] In at least one embodiment of the present application, the lower end of the plug body 7 is in a cone shape. In this way, the internal outer spring and the external lower end cone structure are adopted to maintain the structural characteristics and design functions of the original hole plug, so that the irradiated sample hole plug used on the irradiated sample holder of the nuclear power unit can be suitable for the pressurized water reactor type nuclear power unit, easy to install, can be installed and guided, and can maintain the axial elastic constraint after installation in the reactor, maintaining its original design function.

[0035] In at least one embodiment of the present application, reference Figure 4 and Figure 5 , the irradiated sample hole plug 11 also includes a grabbing operation sleeve 8. The grabbing operation sleeve 8 is connected to the core rod 5 by threads and installed in the center of the plug body 7 to play the role of driving the stopper 10. In this way, in the natural state, the core rod 5 is located in the lower position under the action of the spring force; when the grabbing operation sleeve 8 is extracted upward, the grabbing operation sleeve 8 drives the core rod 5 to move upward. When the grabbing operation sleeve 8 is lifted up, the connecting rod slider mechanism of "grabbing operation sleeve 8-core rod 5-connecting rod 6-stopper 10" plays a driving chain transmission role, so that the stopper 10 is retracted, and does not form interference self-locking with the flange surface of the upper component. The irradiated sample hole plug 11 can be smoothly taken out upward and separated from the internal components of the pile, that is, the effect of retracting the stopper 10 first and then taking out the hole plug 11 is achieved.

[0036] In at least one embodiment of the present application, the grabbing operation sleeve 8 is cylindrical, and a plurality of gaps are evenly arranged in the circumferential direction. In this way, the grabbing tool can be used for grabbing by utilizing the plurality of gaps.

[0037] For example, the plurality of neutral gears may be 3 neutral gears.

[0038] In at least one embodiment of the present application, reference Figure 4 and Figure 5 The irradiated sample hole plug 11 further includes an end cap 9. The end cap 9 is fixed to the plug body 7 by threads. In this way, the core rod 5 moves up and down within a certain range in the center of the plug body 7 through the limiting action of the end cap 9 and the inner spring 4.

[0039] It should be noted that the combination of the various technical features in the embodiments of the present application is not limited to the combination described in the embodiments of the present application or the combination described in the specific embodiments, and all technical features described in the present application can be freely combined or combined in any way unless there is a contradiction between them.

[0040] As shown in this application and claims, unless the context clearly indicates an exception, the words "a", "an" and / or "the" do not refer to the singular and may also include the plural. Generally speaking, the term "comprising" only indicates that the steps and elements that have been clearly identified are included, and these steps and elements do not constitute an exclusive list. The method or device may also include other steps or elements.

[0041] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. An irradiated sample hole plug, characterized in that: It includes an upper cylinder, a pin, an outer spring, an inner spring, a core rod, a connecting rod, a plug body and a stopper. Wherein, the stopper is fixed to the plug body by the pin and is configured to rotate around the pin shaft; the upper cylinder is installed on the plug body by two pins; the outer spring is installed between the upper cylinder and the plug body, and the upper cylinder compresses the outer spring by moving up and down in the pin holes on both sides of the plug body; the inner spring is arranged in the gap between the core rod and the plug body, the core rod is connected to the connecting rod by the pin, the connecting rod is connected to the stopper by the pin, and the stopper is fixed to the plug body by the pin; The driving method of the stopper relies on the core rod and the connecting rod. When the core rod is in the upper position, the connecting rod drives the stopper to rotate clockwise around the pin shaft and retract into the plug body; when the core rod is in the lower position, the connecting rod drives the stopper to rotate counterclockwise around the pin shaft, and the stopper extends out of the outer surface of the plug body, forming axial interference with the flange surface of the upper component to achieve self-locking.

2. The irradiated sample hole plug according to claim 1, characterized in that: The thickness of the irradiated sample hole plug is greater than the thickness of the hanging basket flange.

3. The irradiated sample hole plug according to claim 1, characterized in that: The lower end of the plug body is in a cone shape.

4. The irradiated sample hole plug according to claim 1, characterized in that: Also includes grabbing operating sleeve, Wherein, the grabbing operation sleeve is connected to the core rod through threads and is installed at the center of the plug body to play the role of driving the stopper.

5. The irradiated sample hole plug according to claim 4, characterized in that: The grabbing operation sleeve is cylindrical, and a plurality of gaps are evenly arranged in the circumferential direction of the grabbing operation sleeve.

6. The irradiated sample hole plug according to any one of claims 1 to 5, characterized in that: Also includes end caps, Wherein, the end cover is fixed on the plug body by threads.

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