Inspection method and device for bottom of protective tube assembly and mating surface of nuclear fuel assembly

Abstract

The invention relates to the technical field of maintenance engineering of nuclear power plant equipment, in particular to an inspection method and device for the bottom of a protective tube assembly and the mating surface of a nuclear fuel assembly. The inspection method of the present invention is as follows: a monitoring camera is installed at the bottom of the inspection well to obtain images of the bottom of the inspection well; the automatic inspection device is placed in the inspection well, and the automatic inspection device is remotely controlled to dive below the protection tube assembly, and the depth is adjusted and positioned Direction coordinates; remotely control the automatic inspection device to move to the preset position on the mating surface between the bottom of the protection tube assembly and the nuclear fuel assembly, take the preset position as the starting point for inspection, and perform image acquisition according to the preset scanning path until The image covers the entire bottom of the protective tube assembly and the mating surface of the fuel assembly to complete the inspection. The device includes: a suspension ring, an inspection well, a surveillance camera, and an automatic inspection device. The invention improves the inspection efficiency and reduces the time occupied by the inspection for the suspension ring of the reactor building.

Description

technical field [0001] The invention relates to the technical field of maintenance engineering of nuclear power plant equipment, in particular to a method and a device for inspecting the bottom of a protection tube assembly and the mating surface of a nuclear fuel assembly. Background technique [0002] The protective tube assembly of the VVER-1000 nuclear power unit is a welded metal cylinder, which is the key equipment to ensure the precise positioning and isolation of the head of the nuclear fuel assembly in height and plane, and to place the control rod assembly. The protective tube assembly has the characteristics of high manufacturing technical standards and great difficulty, and it is difficult to replace. After the reactor is in operation, the protective tube assembly has been exposed to neutron radiation for a long time, which has high radioactivity and high pollution. It is difficult and time-consuming to inspect it during service, so it is more inclined to use aux...

AI Technical Summary

Problems solved by technology

The video inspection time window of the bottom of the protection tube assembly and the mating surface of the nuclear fuel assembly is a sub-critical path during the outage. The above inspection method requires multiple rotations of the protection tube assembly to complete the scanning of the entire mating surface, and the inspection efficiency is low; The plant ring hangs for a long time

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