Device and method for measuring torsional deformation in unloading process of nuclear fuel assembly

Abstract

The invention discloses a device and a method for measuring torsional deformation in a nuclear fuel assembly unloading process, and belongs to the field of underwater nuclear fuel assembly measurement. The device comprises a measurement equipment main body and a data acquisition and processing system. The measuring equipment body is located in the transmission pool through the upper boss, the ten sets of line laser measuring modules are installed in the measuring equipment body, and the assembly supporting seat is located above a bottom plate of the measuring equipment body. In the unloading process, the unloaded fuel assembly is hoisted into the assembly supporting base from the fuel basket through the spent crane, the ten sets of line laser measuring modules collect contour data of a strip, an upper pipe base and a lower pipe base on the fuel assembly at the same time, and then the data collecting and processing system calculates and analyzes the torsional deformation amount of the fuel assembly. And after the measurement is finished, the fuel assembly is hoisted into the spent fuel pool grillwork through the sluice gate channel by the spent crane.

Description

Technical Field

[0001] The present invention belongs to the field of nuclear fuel assembly measurement, and particularly relates to a device and method for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly, which is used for accurately measuring the torsional deformation amount of the nuclear fuel assembly during the overhaul and unloading of a nuclear power unit. Background Art

[0002] The nuclear fuel assembly is the core of nuclear power. It operates in a high-temperature, high-pressure, strong nuclear radiation, and underwater environment for a long time, and is prone to torsional deformation. Excessive torsional deformation of the fuel assembly will cause interference with other assemblies and make it difficult to be inserted into the reactor again. Therefore, the torsional deformation amount of the nuclear fuel assembly is an important index for evaluating the operation of the nuclear fuel assembly. The overhaul and unloading of a nuclear power unit is a process of transferring the nuclear fuel assembly from the reactor pool to the spent fuel pool. At this time, the fuel assembly has just stopped operating for a short time, and the torsional deformation amount of the fuel assembly is basically the same as that during its operation in the reactor. Therefore, the unloading period is the best window period for measuring the torsional deformation amount of the fuel assembly. In addition, since the unloading period is a key path for the overhaul of a nuclear power unit, the fuel assembly torsion measurement needs to minimize the measurement time while ensuring the measurement accuracy and reduce the occupation of the key path of the overhaul.

[0003] Currently, the measurement of nuclear fuel assemblies mainly focuses on parameters such as bending deformation amount and external dimensions, and there is a lack of a method for measuring torsional deformation amount. Based on this situation, a method and device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly are designed and invented. Summary of the Invention

[0004] To solve the above technical problems, the present invention provides a device and method for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly.

[0005] The technical solution adopted by the present invention to solve its technical problems is as follows:

[0006] A device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly, the device comprising: a main body of the measuring device, the main body of the measuring device being located in a transfer pool, the main body of the measuring device including an upper bracket, a lower extension bracket, a bottom bracket, a component support seat, a mounting bracket, and a line laser measurement module; the upper bracket is fixedly connected to a boss above the transfer pool, and the upper bracket, the lower extension bracket, the bottom bracket, the component support seat, and the mounting bracket are welded into a whole, and the line laser measurement module is connected to the mounting bracket by bolts.

[0007] A method for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly, comprising the following steps:

[0008] Step 1: Simultaneously collect and obtain the contour data of the lower nozzle, upper nozzle, and strip of the fuel assembly;

[0009] Step 2: Convert each contour data to a unified coordinate system respectively;

[0010] Step 3: Redraw the outer contour of the lower nozzle;

[0011] Step 4: Redraw the outer contours of each strip and the upper nozzle;

[0012] Step 5: Calculate the torsional deformation amount and offset amount of each strip and the upper nozzle relative to the lower nozzle based on the outer contour of the lower nozzle;

[0013] Step 6: Output a report on the torsional deformation amount and offset amount of the fuel assembly.

[0014] The beneficial effects of the present invention are:

[0015] By using the above-mentioned device and method for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly, the torsional deformation amount of the fuel assembly can be synchronously measured while unloading, and the torsional deformation amount of the fuel assembly can be calculated only by collecting the data of a certain edge of the fuel assembly, which has the advantages of low measurement difficulty, high measurement accuracy, short measurement time, etc. Description of the Drawings

[0016] Figure 1 is a schematic diagram of a device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly according to the present invention;

[0017] Figure 2 is a schematic diagram of the main body of the measuring device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly according to the present invention;

[0018] Figure 3 is a schematic diagram of the side view direction of the position of the line laser measurement module and the fuel assembly in a device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly according to the present invention;

[0019] Figure 4 is a schematic diagram of the top view direction of the position of the line laser measurement module and the fuel assembly in a device for measuring the torsional deformation amount during the unloading process of a nuclear fuel assembly according to the present invention;

[0020] Figure 5 is a schematic diagram for calculating the torsional deformation amount and offset amount according to the present invention.

[0021] In the drawings, the reference numerals are: 1. Main body of the measuring device, 2. Fuel assembly, 3. Transfer pool, 4. Fuel basket, 5. Water gate channel, 6. Spent fuel pool grid, 101. Upper support, 102. Lower extension support, 103. Bottom support, 104. Component support seat, 105. Mounting bracket, 106. Line laser measurement module, 201. Lower nozzle contour data, 202. Strip and upper nozzle contour data. Detailed Embodiments

[0022] In order to make the objectives, technical solutions and advantages of the present invention more clear and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other. To achieve the above objectives, the present invention adopts the following technical solutions.

[0023] As Figure 1 shown, the present invention relates to a device for measuring the torsional deformation amount during the discharge process of a nuclear fuel assembly. The main body 1 of the measuring device is installed in the transfer pool 3. During measurement, first, the discharged fuel assembly 2 is lifted from the fuel basket 4 by a spent fuel crane and placed in the assembly support seat 104 of the main body 1 of the measuring device. Then, the strip, upper nozzle, and lower nozzle contour data on the fuel assembly 2 are simultaneously collected by ten line laser measurement modules 106 of the main body 1 of the measuring device. Subsequently, the data acquisition and processing system calculates and analyzes the torsional deformation amount of the fuel assembly 2. After the measurement is completed, the fuel assembly is lifted by the spent fuel crane through the water gate channel 5 and placed in the spent fuel pool grid 6.

[0024] As Figure 2 shown, the main body 1 of the measuring device includes an upper support 101, a lower extension support 102, a bottom support 103, an assembly support seat 104, a mounting bracket 105, and a line laser measurement module 106. The mounting bracket 105 is used to install the line laser measurement module 106. The upper support 101 is fixedly connected to the convex platform above the transfer pool 3 and is used to support the main body 1 of the measuring device. The lower extension support 102 is used to connect the upper support 101 and the bottom support 103, so as to ensure a certain distance between the bottom support 103 and the convex platform above the transfer pool 3. The bottom support 103 is used to install the assembly support seat 104, and further support the fuel assembly 2. The upper support 101, the lower extension support 102, the bottom support 103, the assembly support seat 104, and the mounting bracket 105 are welded into a whole, and the line laser measurement module 106 is connected to the mounting bracket 105 by bolts.

[0025] As Figure 3 shown, the installation heights of the ten line laser measurement modules 106 on the main body 1 of the measuring device are respectively consistent with the elevations of the upper nozzle, eight strips, and lower nozzle of the fuel assembly 2. The ten line laser measurement modules 106 use the coordinate system of the lowermost line laser measurement module, that is, the line laser measurement module that collects the contour data of the lower nozzle, as the unified coordinate system. The conversion relationship between the coordinate systems of the remaining line laser measurement modules and the coordinate system of the lowermost line laser measurement module can be calibrated by a calibration piece, and a coordinate transformation matrix is obtained.

[0026] As Figure 3 、 4As shown, during the machining of the edge of the component support base 104, it faces the line laser measurement module 106, so as to ensure that a certain edge of the fuel assembly 2 faces the line laser measurement module 106 during measurement.

[0027] The process of calculating the torsional deformation amount by the data acquisition and processing system proposed in the present invention is as follows:

[0028] Step 1: Simultaneously collect and obtain the contour data of the lower tube seat, upper tube seat, and strip of the fuel assembly 2;

[0029] Step 2: Convert each contour data to a unified coordinate system respectively; according to the coordinate transformation matrix of the installation positions of the line laser measurement modules 106 on the equipment main body 1 relative to the lowermost line laser measurement module 106, each contour data can be unified to the coordinate system of the lowermost laser measurement module.

[0030] Step 3: Redraw the outer contour of the lower tube seat;

[0031] Step 4: Redraw the outer contours of each strip and the upper tube seat;

[0032] Step 5: Taking the outer contour of the lower tube seat as a reference, the torsional deformation amount θ and the offset amounts δx and δy of the outer contours of each strip and the upper tube seat relative to the lower tube seat can be measured in the three-dimensional diagram.

[0033] Step 6: Output a report on the torsional deformation amount and offset amount of the fuel assembly 2.

[0034] As Figure 5 shown, when calculating the torsional deformation amount of the fuel assembly, taking the outer contour data 201 of the lower tube seat as a reference, the torsional deformation amount θ and the offset amounts δx and δy of the outer contour data 202 of each strip and the upper tube seat relative to the lower tube seat are measured in the three-dimensional model.

Claims

1. A measuring device for the torsional deformation amount during the discharge process of a nuclear fuel assembly, characterized in that The device includes: a measurement device main body located in a transfer pool. The measurement device main body includes an upper bracket, a lower extension bracket, a bottom bracket, a component support base, a mounting bracket, and a line laser measurement module. The upper bracket is fixedly connected to the boss above the transfer pool. The upper bracket, the lower extension bracket, the bottom bracket, the component support base, and the mounting bracket are welded into a whole. The line laser measurement module is connected to the mounting bracket by bolts.

2. The measuring device for the torsional deformation amount during the discharge process of a nuclear fuel assembly according to claim 1, characterized in that, The unloaded fuel assembly is hoisted from the fuel basket by a spent fuel crane and placed in the component support base of the measurement device main body. Then, ten groups of line laser measurement modules of the measurement device main body simultaneously collect the contour data of the strips, upper nozzle, and lower nozzle on the fuel assembly respectively. After that, the data acquisition and processing system calculates and analyzes the torsional deformation amount of the fuel assembly. After the measurement, the fuel assembly is hoisted into the spent fuel pool grid through the water gate channel by the spent fuel crane.

3. The measuring device for the torsional deformation amount during the discharging process of a nuclear fuel assembly according to claim 1, wherein The installation heights of the line laser measurement modules on the measurement device main body are respectively consistent with the elevations of the upper nozzle, strips, and lower nozzle of the fuel assembly.

4. A measuring device for the torsional deformation amount during the discharge of a nuclear fuel assembly according to claim 3, characterized in that, Ten groups of line laser measurement modules are provided. When collecting data, each module simultaneously triggers to collect the contour data of the upper nozzle, eight strips, and lower nozzle of the fuel assembly.

5. A measuring device for torsional deformation during the discharge of a nuclear fuel assembly according to claim 4, characterized in that, Taking the coordinate system of the lowermost line laser measurement module, i.e., the line laser measurement module that collects the contour data of the lower nozzle, as the unified coordinate system, the conversion relationships between the coordinate systems of the remaining line laser measurement modules and the coordinate system of the lowermost line laser measurement module are obtained through calibration with calibration parts.

6. The measuring device for the torsional deformation amount during the discharge of a nuclear fuel assembly according to claim 1, characterized in that The component support base makes a certain edge of the fuel assembly basically face the line laser measurement module.

7. A method for measuring the torsional deformation amount during the discharge process of a nuclear fuel assembly, characterized in that, It includes the following steps: Step 1: Simultaneously collect and obtain the contour data of the lower nozzle, upper nozzle, and strips of the fuel assembly. Step 2: Respectively convert each contour data to the unified coordinate system. Step 3: Redraw the outer contour of the lower nozzle. Step 4: Redraw the outer contours of each strip and the upper nozzle. Step 5: Taking the outer contour of the lower nozzle as the reference, calculate the torsional deformation amount and offset amount of the outer contours of each strip and the upper nozzle relative to the lower nozzle. Step 6: Output a report on the torsional deformation amount and offset amount of the fuel assembly.

8. A method for measuring the torsional deformation amount during the discharging process of a nuclear fuel assembly according to claim 7, characterized in that, According to the coordinate transformation matrix between the installation positions of each line laser measurement module on the measurement device main body and the lowermost line laser measurement module, each contour data is unified to the coordinate system of the lowermost line laser measurement module respectively.

9. A method for measuring the torsional deformation amount during the discharge of a nuclear fuel assembly according to claim 7, characterized in that The offset amount includes the xy-axis offset amounts δx and δy.

10. A method for measuring the torsional deformation amount during the discharge of a nuclear fuel assembly according to claim 7, characterized in that, When calculating the torsional deformation amount of the fuel assembly, taking the outer contour data of the lower nozzle as the reference, measure the torsional deformation amount θ and the offset amounts δx and δy of the outer contour data of each strip and the upper nozzle relative to the lower nozzle in the three-dimensional model.

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