Method for detecting deformation of fuel assembly after irradiation of pressurized-water reactor nuclear power plant and implementation device thereof

Abstract

The invention belongs to the technical field of detection, and in particular relates to a device and a method for detecting deformation size of a fuel assembly after irradiation of a pressurized-water reactor nuclear power plant, which solve the problem of low precision and poor insurance in the prior art. The detecting device mainly comprises an annular base (1) and detection sets (2), wherein aplurality of detection sets (2) are evenly distributed on the annular base (1); each detection set (2) comprises a pair of detection units (3) placed reversely in parallel; the number of the detection units (3) is the same as the edge number of the fuel assembly (10); and the detecting method adopts the detection set (2) consisting of the two detection units (3) to measure the width of an opposite side of the fuel assembly, the diameter of fuel rods and the clearance between the fuel rods. The method and the device can inspect the curve and torsion of the fuel assembly after the irradiation of the nuclear power plant, the opposite side distance of a grillwork and the clearance between the fuel rods; and edges of the fuel assembly can be inspected at the same time by adopting the arrangement of a plurality of units, and the detection efficiency is high.

Description

technical field [0001] The invention relates to a detection device and a detection method for a fuel assembly of a nuclear power plant, in particular to a detection method and a device for detecting the deformation of a fuel assembly after irradiation in a pressurized water reactor nuclear power plant. Background technique [0002] The fuel assembly of the pressurized water reactor nuclear power plant is generally designed in a square or hexagonal shape, with fuel rods, control rod guide tubes and neutron measuring tubes. The assembly is 3 to 4 meters long. Composed of grid frame and down tube seat. There are multiple grids, which are equidistantly distributed in the length direction of the assembly, and fix the fuel rods and control rod guide tubes together. The structure of the hexagonal assembly is as follows: figure 1 shown. The irradiated components are generally stored in storage racks in a fuel pool filled with boron-containing water, such as figure 2 shown. [0...

AI Technical Summary

Problems solved by technology

[0004] However, due to the strong radioactivity of the fuel assembly after irradiation and the continuous release of waste heat, it needs to be stored in boron-containing water, which cannot be measured at close range, and general measuring equipment cannot be used

At present, the video method is generally used for inspection, but this method has low precision and can only roughly observe the deformation of the component

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