Cleaning tool for detection device for nuclear reactor rod cluster control assembly (RCCA)

Abstract

The invention belongs to the technical field of nuclear power plant equipment radioactive decontamination, particularly relates to a cleaning tool for a detection device for a nuclear reactor rod cluster control assembly (RCCA). A connection plate is in a rectangular hollow cavity structure, a plurality of holes communicated with the rectangular hollow cavity are evenly distributed in one lateral surface, and two ashore air pipe connectors communicated with the rectangular hollow cavity are symmetrically installed on the other lateral surface. Cleaning rods are respectively in a cylindrical hollow cavity structure, wherein a plurality of air holes are evenly distributed in each cleaning rod. A connection handle is in a rectangular plate-shaped structure, wherein a plurality of through holes are evenly distributed in the connection handle. A plurality of the cleaning rods are combined into a cleaning rod group through the connection handle, the upper end of each cleaning rod is connected and fixed with one through hole in the connection handle and is connected with a corresponding hole in the connection plate through an air pipe, an air source is respectively connected with the two ashore air pipe connectors through a pipeline, and the pipelines between the air source and the two ashore air pipe connectors are sequentially provided with a stop valve and a pressure regulating valve. The cleaning tool for the detection device for the nuclear reactor RCCA is capable of effectively removing pollutant on the detection device, and lowering the radioactive dosage of the detection device.

Description

technical field [0001] The invention belongs to the technical field of radioactive decontamination of nuclear power plant equipment, and in particular relates to a cleaning tool for an inspection device of a control rod bundle assembly of a nuclear reactor. Background technique [0002] The nuclear reactor control rod bundle assembly (RCCA) plays a very important role in the whole nuclear power plant, which is mainly used for regulating the power of the reactor and shutting down the reactor in an emergency. With the increase of service time, RCCA will appear defects such as swelling, wear and cracks, so it is necessary to conduct in-service inspections, and analyze and compare the data obtained from multiple inspections to evaluate the speed and speed of wear and swelling. Trends in order to maximize the life of RCCAs and ensure the safe and economical operation of nuclear power plants. [0003] Because the control rod has high radioactivity after operation, and the surface...

AI Technical Summary

Problems solved by technology

Because there is a lot of strong radioactive dust attached to the surface of the rod bundle, during the up and down movement of the rod bundle, the dust on the surface of the rod bundle will be scraped off by the guide device on the sleeve hole and fall onto the inspection device, so that the inspection device will have a strong after use. Radioactive, which makes the operator inaccessible, and even exceeds 250 mSv / h in some cases. If it is not cleaned, it will be limited by the amount of effluent water, which will cause the inspection device to fail to effluent, and will make the operator in subsequent loading and unloading, transportation and Due to the extremely high doses of radiation during maintenance, it is important to decontaminate this inspection unit

RCCA in-service inspections are usually carried out in cooling water pools or spent fuel pools. Due to the special requirements for water quality in the pools and the complexity of the structure of the RCCA inspection device itself, many conventional cleaning methods are not feasible, such as brushing, wiping, Washing with water, etc., and it is impossible to clean the inside of the inspection device, and because the radiation is too strong, the operator cannot access it; and because of the special structure and extremely expensive price of the detection probe on the inspection device, cleaning methods such as ultrasonic waves cannot be used. Otherwise, the detection probe may be damaged

[0004] At present, methods such as wiping, washing or ultrasonic vibration decontamination are used for decontamination of radioactively contaminated equipment at home and abroad, but there is no set of special decontamination tools for RCCA inspection devices developed for the characteristics of RCCA inspection devices.

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