Collimator device capable of automatically adjusting gamma ray flux and measuring system

Abstract

The invention provides a collimator device capable of automatically adjusting the gamma ray flux and a measuring system. A collimation window is formed in the front section of a collimator outer shielding body, a through hole is formed in the rear section of the collimator outer shielding body, a detector penetrates through the through hole for connection, and gamma rays can enter the detector from the collimation window. A servo motor and a speed-changing gear box are connected with a lead screw through a gear assembly connecting rod and a gear assembly; two guide rails are inclined inwards along the collimation window and are symmetrically arranged on the two sides by taking the detector as the center; the servo motor is controlled to drive the lead screw, then a collimation opening shielding sliding block is driven by a shielding block sliding connecting rod, the position of the collimation opening shielding sliding block is adjusted, the size of the collimation window is changed, and the adjusting function of the gamma ray flux is realized. The device can automatically adjust the flux of the gamma rays, with the sensitive volume, entering the detector according to the initial measurement value, has a similar adjusting function for low-energy rays to high-energy rays, and is easy to operate, compact in structure and suitable for nuclear power plants and nuclear technology application radioactive waste detection systems.

Description

technical field [0001] The present invention relates to the technical field of nuclear radiation detection, in particular to a collimator device capable of automatically adjusting gamma ray flux and its measuring system, especially to a detection system collimator capable of automatically adjusting gamma ray flux. straight device. Background technique [0002] Segmented Gamma Scanning (SGS) and Tomographic Gamma Scanning (TGS), as important non-destructive analysis (Non-destructive Assay, NDA) techniques, have been widely used in nuclear power plants Inspection of barreled waste. Its main principle is to measure the count and energy of gamma rays according to the radiation detector, combined with the energy spectrum of gamma rays measured by a multi-channel analyzer, determine the type of nuclide, and then reconstruct the activity according to the count rate to determine the nuclei element activity. High-purity germanium detectors are now mostly used for gamma-ray measure...

AI Technical Summary

Problems solved by technology

In practical application, the purpose of reducing the number of rays entering the sensitive volume of the detector can be achieved by adding a shielding block. However, the study found that the attenuation effect of this method on different energy rays is very different. High-energy rays have strong penetration ability and attenuation The ratio is significantly smaller than that of low-energy rays, so when high-energy rays are measured normally, some low-energy rays cannot penetrate the shielding block and enter the sensitive volume of the detector, resulting in large measurement errors or even ineffective measurement

The method of changing the opening size by adjusting the overall structure of the collimator can solve the problem that low-energy rays cannot be detected, but due to design defects, it needs to occupy a large space for adjustment of the overall structure, which is not conducive to the promotion and application in the actual detection system

In addition, compared with SGS technology, TGS technology requires a collimator with a smaller aperture, but there is currently no collimator device that can automatically adjust the aperture size and take into account both SGS and TGS measurement systems

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