CN-121977970-A - Neutron absorption material B10 surface density measuring device and method

CN121977970ACN 121977970 ACN121977970 ACN 121977970ACN-121977970-A

Abstract

The invention provides a device and a method for measuring the surface density of a neutron absorbing material B10. The device comprises a sample frame, a neutron detector, a control system, a driver and a control system, wherein the sample frame is used for slidably arranging a sample to be measured and a standard sample, the neutron detector is arranged on the sample frame and used for measuring and outputting neutron data of a neutron beam after passing through the sample to be measured or the standard sample, the control system is used for receiving the measurement data of the neutron detector, calculating the B10 area density of the sample to be measured and controlling the measurement position of the sample to be measured and/or the standard sample on the sample frame, and the driver is respectively connected with the control system and the sample frame and drives the sample to be measured and/or the standard sample to move horizontally and/or vertically on the sample frame based on instructions of the control system. The invention can accurately control the measurement position of the neutron absorption material, and can accurately measure the B10 surface density by using the standard sample with the same raw material and processing technology as the sample to be measured, thereby accurately evaluating the neutron absorption performance of the neutron absorption material.

Inventors

LI GUOJIAN
ZHANG YAPING
YANG SHUANGLIANG
WANG DONGHUI
Wu Qiongzi

Assignees

国核电站运行服务技术有限公司

Dates

Publication Date: 20260505
Application Date: 20241030

Claims (10)

1. The neutron absorption material B10 surface density measuring device is characterized by comprising a control system, a driver, a neutron detector and a sample frame; the sample rack is used for slidably arranging a sample to be tested and a standard sample; The neutron detector is arranged on the sample frame and is used for measuring and outputting neutron data of a neutron beam after passing through a sample to be measured or a standard sample; The control system is used for receiving the measurement data of the neutron detector, calculating the B10 surface density of the sample to be measured, and controlling the measurement position of the sample to be measured and/or the standard sample on the sample frame; The driver is respectively connected with the control system and the sample rack, and drives the sample to be tested and/or the standard sample to move horizontally and/or vertically on the sample rack based on instructions of the control system.
2. The neutron absorbing material B10 areal density measurement device of claim 1, wherein the control system comprises an input module, a control module, a data monitoring module, a data analysis module, and a storage module; the input module is used for inputting size information, measurement position information and identification information of a sample to be measured, wherein the measurement position information comprises a position point number and a distance between a measurement position and the edge of the sample; The control module is used for generating a control instruction based on the test position information and controlling the driver to drive the sample to be tested and/or the standard sample to move on the sample rack until reaching a preset measurement position; the data monitoring module is used for monitoring and receiving measurement data of the neutron detector in real time, wherein the measurement data comprise neutron count and neutron transmissivity; The data analysis module is used for calculating a functional relation between the transmissivity of the neutron absorbing material in the standard sample and the B10 surface density according to the measured data of each standard sample, calculating the B10 surface density of the sample to be measured based on the measured data of the sample to be measured and the functional relation between the transmissivity of the neutron absorbing material in the standard sample and the B10 surface density, and evaluating the neutron absorption performance of the sample to be measured; The storage module is used for storing historical measurement data, functional relation data between the transmissivity of the neutron absorbing material in the standard sample and the surface density of the B10, wherein the historical measurement data comprise historical measurement size information, measurement position information, identification information and measurement data of the tested sample and the standard sample; The identification information comprises sample numbers, raw material component information and processing technology information.
3. The neutron absorbing material B10 areal density measurement device of claim 2, wherein the control system further comprises an operation module and a matching module; The operation module is used for calculating the measurement position of the sample to be measured after the size change according to the size difference for the sample to be measured with the same identification information but different sizes; The matching module is used for matching standard samples with the same identification information in the storage module according to the identification information of the sample to be detected.
4. The neutron absorbing material B10 areal density measurement device of claim 1, wherein the sample holder comprises a horizontal base, a first support bar, a second support bar, and a telescoping tube; the first support rod and the second support rod are vertically arranged at two ends of the horizontal base respectively; the neutron detector is fixed on the first supporting rod; The second support rod is provided with a sliding rail and a plurality of sliding blocks, and the sliding blocks move along the sliding rail; One end of the telescopic tube is fixed with a sample to be measured or a standard sample, the other end is fixedly connected with the sliding block; the driver is connected with the sliding block and drives the sliding block to drive the sample to be tested and/or the standard sample to slide horizontally and/or vertically on the second supporting rod.
5. The neutron absorbing material B10 surface density measurement device according to claim 4, wherein a spring is arranged in the telescopic tube, one end of the spring is connected with the sliding block, and the other end of the spring is connected with a sample to be measured or a standard sample.
6. The device for measuring the areal density of the neutron absorbing material B10 according to claim 4, wherein the first supporting rod and/or the second supporting rod are/is arranged on the horizontal base in a sliding manner, and move leftwards and rightwards along the connecting direction of the first supporting rod and the second supporting rod.
7. The neutron absorbing material B10 areal density measurement device of claim 4, further comprising a beam blocking support connected to the driver, the beam blocking support being disposed at a lower end on the horizontal base and at an upper end with a thick absorber material; the driver drives the thick absorber material to move vertically along the beam blocking support.
8. The neutron absorbing material B10 areal density measurement device of claim 1, wherein the driver is a servo motor.
9. A method for measuring the areal density of a neutron absorbing material B10, wherein the method is applied to the neutron absorbing material B10 areal density measuring device according to any one of claims 1 to 8, and comprises the steps of: Placing a sample to be tested on a sample rack; inputting size information, measurement position information and identification information of a sample to be measured, wherein the identification information comprises sample numbers, raw material component information and processing technology information; automatically matching a standard sample with the same identification information as the sample to be detected, wherein the B10 surface density of the standard sample is known; Placing a standard sample on a sample holder; The control system controls the driver to drive the sample to be measured and/or the standard sample to the measuring position; placing a neutron source, and aligning the neutron source to a measuring position of a sample to be measured and/or a standard sample through a collimator; Sequentially measuring standard samples with different B10 surface densities, and establishing a functional relation between the transmissivity of neutron absorbing materials in the standard samples and the B10 surface densities; neutron transmittance measurement is carried out on a sample to be measured; and calculating the B10 surface density of the sample to be measured based on neutron transmissivity data of the sample to be measured and the functional relation between the neutron absorbing material transmissivity and the B10 surface density of the standard sample.
10. The method for measuring the surface density of the neutron absorbing material B10 according to claim 9, wherein when measuring the surface density of the B10 before and after the irradiation of the sample to be measured, If the size of the irradiated sample to be measured is unchanged, the control system controls the driver to drive the sample to be measured to move to the same position as the first measurement to perform B10 surface density measurement; if the size of the irradiated sample to be measured changes, after the size information of the sample to be measured is input, the control system calculates the measurement position of the irradiated sample to be measured according to the size difference, and controls the driver to drive the sample to be measured to move to the corresponding measurement position after irradiation to perform B10 surface density measurement.

Description

Neutron absorption material B10 surface density measuring device and method Technical Field The invention relates to the technical field of neutron absorption material measurement, in particular to a device and a method for measuring the B10 surface density of a neutron absorption material. Background Neutron absorbing materials (also known as neutron poison test pieces) can absorb neutrons, control the speed and scale of nuclear reactions, and are important components for maintaining subcritical states in spent fuel pools of nuclear power plants. Boron (especially boron-10 isotope) has extremely high absorption cross section for the neutron, so the neutron absorption material is usually boron-containing materials, such as boron-containing stainless steel, boron aluminum alloy, B 4 C/Al ceramic, B 4 C/Al composite material and the like. However, the neutron absorption material is susceptible to the effects of neutrons, gamma irradiation, boric acid water environment and other factors, the problems of expansion deformation, corrosion and the like occur, and the safety of fuel storage is seriously threatened, so that the neutron absorption performance of the neutron absorption material needs to be continuously monitored and evaluated during the operation of the spent fuel pool, and the safety of fuel storage is ensured. B10 The method comprises the specific processes of generating a neutron beam by using a neutron source, enabling the neutron beam to pass through a group of standard samples and samples to be detected with known surface densities respectively, measuring the quantity of transmitted neutrons by using a detector after the neutron beam passes through the samples, calculating the transmittance of the thermal neutrons, and then calculating the B10 surface density of the samples to be detected by comparing the transmittance of the samples to be detected with the transmittance of the standard samples. Accurate measurement of the B10 areal density of neutron absorbing materials is critical to ensuring safe operation of a nuclear power plant, but the prior art has problems of operational errors, material non-uniformity, etc. in the measurement process, resulting in the accuracy of the measurement results being affected. On the one hand, the difference of the surface density of the sample B10 is caused by the difference of the raw materials of the neutron absorption plate and the processing technology, and if the surface density of the sample to be measured is calculated by utilizing the functional relation between the neutron transmissivity and the surface density constructed by the neutron absorption material standard sample of the other processing technology, the result is inaccurate. On the other hand, the finished neutron absorbing material sample is subjected to anodic oxidation, shot blasting and other treatments, so that the sample is uneven, and if the consistency of the front and rear measuring positions cannot be ensured, the measuring deviation of the B10 surface density test result is also influenced. Taking 31% boron aluminum neutron absorbing material as an example, the corresponding B10 surface density is in the interval 0.03586-0.03965g/cm 2, the maximum relative deviation reaches 10%, the limit value required by individual power plants is 5%, and if the measured positions are different, whether the difference is caused by the reduction of the B10 content or the deviation of the measured positions cannot be judged. Disclosure of Invention The invention aims to provide a device and a method for measuring the surface density of a neutron absorbing material B10, which are used for solving the problems, accurately controlling the measuring position of the neutron absorbing material, and accurately measuring the surface density of the B10 by using standard samples with the same raw materials, the same processing technology and the same processing mode as those of a sample to be measured and accurately evaluating the neutron absorbing performance of the neutron absorbing material. The invention provides a neutron absorption material B10 surface density measuring device, which comprises a control system, a driver, a neutron detector and a sample frame, wherein the driver is arranged on the control system; the sample rack is used for slidably arranging a sample to be tested and a standard sample; The neutron detector is arranged on the sample frame and is used for measuring and outputting neutron data of a neutron beam after passing through a sample to be measured or a standard sample; The control system is used for receiving the measurement data of the neutron detector, calculating the B10 surface density of the sample to be measured, and controlling the measurement position of the sample to be measured and/or the standard sample on the sample frame; The driver is respectively connected with the control system and the sample rack, and drives the sample to be tested and/or the standard sample to