CN-119581075-B - Irradiation sample hole plug for irradiation sample rack of nuclear power unit

Abstract

The application provides an irradiation sample hole plug used on an irradiation sample frame of a nuclear power unit, which comprises an upper cylinder body, a pin, an outer spring, an inner spring, a core bar, a claw spring, a plug body and a claw. The upper cylinder is mounted on the plug body by 2 pins. An outer spring is arranged between the upper cylinder and the plug body, and the upper cylinder compresses the outer spring by moving up and down in pin holes at two sides of the plug body. The inner spring is arranged at the gap between the core rod and the plug body. The hook claw is fixed on the plug body through a pin and is configured to rotate around the pin shaft, and the hook claw is driven by the core bar and the hook claw spring. The application adopts mechanical self-locking, optimizes the structure without changing the original design, adopts a hook claw structure, and increases the anti-flushing function so as to solve the technical problem of how to reduce the problem of easy flushing of the irradiation sample hole plug in the prior art.

Inventors

• ZHOU WEI
• ZHAO YUAN
• HAN GUANGHUI
• LI ZHENGGUANG
• YU XIANGLONG
• NIE WENZHE
• MENG WEIMIN
• LU SHAOWEI
• ZHOU TONG
• Ling Chaojie

Assignees

• 中核运维技术有限公司

Dates

Publication Date

20260512

Application Date

20241111

Claims (4)

1. 1. An irradiation sample hole plug used on an irradiation sample frame of a nuclear power unit is characterized by comprising an upper cylinder body, a pin, an outer spring, an inner spring, a core bar, a claw spring, a plug body, a claw and a grabbing operation sleeve, The upper cylinder is arranged on the plug body through 2 pins, the outer spring is arranged between the upper cylinder and the plug body, the upper cylinder compresses the outer spring through moving up and down in pin holes on two sides of the plug body, and the inner spring is arranged at a gap between the core rod and the plug body; the driving mode of the hook claw is that the core bar and the hook claw spring are relied on, and the core bar is contacted with the upper contact surface of the hook claw when in an upper position so as to overcome the force of the hook claw spring to fold the hook claw; One side of the lower surface of the inner pile component is a conical surface and the other side is a plane, and the hook claw can only act on the plane, so that only 1 hook claw is arranged; The thickness of the irradiation sample hole plug is larger than that of the hanging basket flange, so that the upper end of the irradiation sample hole plug is arranged on the hanging basket flange of the internal pile member, the lower end of the irradiation sample hole plug penetrates through the whole hanging basket flange thickness, the hook claw is spread to protrude out of the plug body, and the hook claw is supported below the hanging basket flange.
2. 2. The irradiated sample well plug of claim 1, wherein the sample is a solid sample, The lower end of the plug body is conical.
3. 3. The irradiated sample well plug of claim 1, wherein the sample is a solid sample, The grabbing operation sleeve is cylindrical, and a plurality of neutral gears are uniformly distributed in the circumferential direction of the grabbing operation sleeve.
4. 4. The irradiated sample well plug of any one of claims 1-3, further comprising an end cap, The end cover is fixed on the plug body through threads.

Description

Irradiation sample hole plug for irradiation sample rack of nuclear power unit Technical Field The application belongs to the technical field of irradiated sample hole plugs for nuclear power, and particularly relates to an irradiated sample hole plug used on an irradiated sample frame of a nuclear power unit. Background An irradiation sample rack is arranged on a hanging basket barrel of the pressurized water reactor inner component. The sample material placed in the irradiation sample holder is identical to the material of the reactor pressure vessel so as to be taken out at different stages during the life of the reactor for mechanical property testing. Correspondingly, holes are formed in the positions, corresponding to the irradiation sample frames, of the basket flanges, so that the irradiation samples can be detached by using special long rod tools in the later period, and in order to generate no extra side flow, hole plugs for the irradiation samples are placed in the holes, and the function of limiting the side flow is achieved when the reactor runs. In pressurized water reactor stacks such as CNP600, CNP1000, wallace one, etc., irradiation sample plugs are mounted on the basket flanges of the lower internals. Currently, referring to fig. 1 and 2, an irradiation sample plug for a pressurized water reactor (also called a pressurized water reactor) is composed of an upper end head 1, an optical axis 2, a base 3 and a spring 4. The hole plug is in radial clearance fit with the flange hole of the hanging basket, the axial direction is unconstrained, and the upper end is an upper internal pile component. During the major repair of the refueling, after the upper internal pile component of the irradiation sample hole plug is disassembled, a constraint part is not arranged above the hole plug, and when a reactor safety injection test is carried out or water is filled into the reactor, namely, the hole plug is flushed out, the hole plug is easy to flush out, so that the irradiation sample hole plug is possibly flushed out by a loop coolant and scattered in the reactor randomly, and a great hidden danger exists. The prior irradiation sample hole plugs of the pressurized water reactor nuclear power unit all adopt the structure, and the related stacks are CNP600, CNP1000, hualong No. one and the like, so that improvement is needed. For example, patent 1 (application number 201910994798.9) discloses a wedge-groove self-locking irradiation sample hole plug and an implementation method thereof, however, the irradiation sample hole plug is not suitable for being used in a pressurized water reactor nuclear power unit, because the wedge-groove self-locking irradiation sample hole plug is self-locked by water flow impact pressure, the self-locking mode is unreliable, two ends of the irradiation sample hole plug extend out and do not meet the hanging basket structure of the nuclear power unit, the hanging basket structure is arranged on a conical hanging basket, the lower part of a hanging basket flange is not flat, the wedge-groove self-locking irradiation sample hole plug is not suitable for being used in the current nuclear power unit, and the upper end of the wedge-groove self-locking irradiation sample hole plug is not provided with elastic components such as springs and the like and is not suitable for being matched in a pile, so that the wedge-groove self-locking irradiation sample hole plug is not used in the nuclear power industry. Patent 2 (application number 201310311304.5) discloses a ball cone irradiation sample hole plug with a self-locking function for a pressurized water reactor, which is also not suitable for a pressurized water reactor nuclear power unit, because the ball cone irradiation sample hole plug is converted into horizontal tension by virtue of a wedge surface by virtue of axial force generated by water flow impact, friction force between the ball cone irradiation sample hole plug and a hole wall is generated, the friction force is utilized to prevent the ball cone irradiation sample hole plug from being punched out, the design principle is unreliable, the punching risk still exists, and engineering application is not performed due to the fact that the technical reliability of generating circumferential friction force by virtue of water flow impact cannot be verified. Are not used in the nuclear power industry. Patent 3 (application number 201910567106.2) discloses a limiting type irradiation sample hole plug and a locking method, wherein the limiting type irradiation sample hole plug is not suitable for a pressurized water reactor nuclear power unit, and is characterized in that a conical surface is arranged below a hanging basket instead of a plane, the limiting type irradiation sample hole plug is not suitable for the pressurized water reactor nuclear power unit, the upper end of the limiting type irradiation sample hole plug is not provided with elastic components such as a spring and t