Centering detection device for welding seam position of lower pipe seat of fuel assembly

Abstract

The utility model belongs to the technical field of nuclear fuel assemblies, and particularly relates to a centering detection device for a welding seam position of a lower pipe seat of a fuel assembly. Comprising a gauge which is L-shaped on the whole. The L-shaped gauge is processed in an integrated manner, and is processed by a Cr12MoV material after heat treatment. The design of the L-shaped gauge in two directions is consistent. The utility model has the beneficial effects that: 1) the welding seam position of the tube socket can be inspected by adopting a non-destructive method, the accuracy of the welding seam position is ensured, and the effective fusion depth of the welding seam is further ensured; and 2) the gauge adopts an L-shaped integrated processing design, the design of the gauge in two directions is consistent, the gauge does not need to be used in different directions, and the use difficulty and misoperation use of an operator are reduced. 3) the gauge is made of a Cr12MoV material with relatively high hardness after heat treatment, and the wear resistance of the gauge after long-time use is ensured; and 4) the gauge has been successfully applied to manufacturing and inspection of a product without a lower tube socket of a positioning table.

Description

Technical Field

[0001] This utility model belongs to the field of nuclear fuel assembly technology, specifically relating to a device for detecting the centering of the weld seam of the lower tube seat of a fuel assembly. Background Technology

[0002] The fuel assembly lower tube seat is assembled and welded from four support legs 1, four lower surrounding plates 2, and one lower connecting plate 3 (e.g., Figure 1 As shown), the following problems exist:

[0003] 1) Due to the characteristics of electron beam welding, the weld is narrow and deep. During the welding process, when the position of the electron beam weld deviates from the position of the weld joint, the effective penetration depth of the weld is easily reduced.

[0004] 2) To ensure weld quality, destructive testing is required to accurately determine the weld position. A newly designed weld position gauge should be used to inspect the weld position after the upper pipe seat is welded, so as to improve the reliability of the product weld quality. Utility Model Content

[0005] The purpose of this invention is to provide a device for detecting the centering of the weld position of the lower tube seat of a fuel assembly, solving the problem of whether the position of the electron beam weld is deviated after the lower tube seat is welded and requiring a destructive detection method. The device is designed with a weld position gauge to achieve non-destructive weld position inspection and improve the reliability of the weld position of the product.

[0006] The technical solution of this utility model is as follows: A device for detecting the centering position of the weld seam of the lower tube seat of a fuel assembly, characterized in that: it includes a gauge that is integrally L-shaped, the L-shaped gauge having two inner sides, a groove of depth c on the inner side, two symmetrical vertical grooves of width d along the center line of the groove, the distance between the center of the vertical groove and the inner end face being a, the distance a being consistent with the dimension from the end face A of the lower connecting plate to the first weld seam and the dimension from the end face B of the support leg to the second weld seam; the distance c being the weld seam reinforcement height + 1.5mm; the distance d being the groove width for observing the weld seam, which is less than the weld seam width.

[0007] The L-shaped gauge is machined in one piece using heat-treated Cr12MoV material.

[0008] The L-shaped gauge is designed in the same direction in both directions.

[0009] The beneficial effects of this utility model are as follows: 1) The newly designed lower pipe seat weld position gauge enables non-destructive inspection of the pipe seat weld position, ensuring the accuracy of the weld position and thus ensuring the effective penetration thickness of the weld. 2) The gauge adopts an L-shaped integrated machining design, with consistent design in both directions, eliminating the need for separate use and reducing the difficulty of operation and the risk of misoperation. 3) The gauge is machined from Cr12MoV material, which has relatively high hardness after heat treatment, ensuring the wear resistance of the gauge during long-term use. 4) This gauge has been successfully applied to the manufacturing inspection of a lower pipe seat without a positioning table. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the lower tube seat structure;

[0011] Figure 2 This is a front view of a device for detecting the centering position of the weld seam of the lower tube seat of a fuel assembly, provided by this utility model.

[0012] Figure 3 This is a top view of a device for detecting the centering position of the weld seam of the lower tube seat of a fuel assembly, provided by this utility model.

[0013] In the diagram: 1. Leg, 2. Lower panel, 3. Lower connecting plate, 4. First weld, 5. Second weld. Detailed Implementation

[0014] The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0015] A device for detecting the alignment of the weld seam of the lower tube seat of a fuel assembly includes an integrally L-shaped gauge, machined as a single piece. It is made of Cr12MoV material, which has relatively high hardness after heat treatment, ensuring the gauge's wear resistance over long-term use. The L-shaped gauge is designed to be identical in both directions, eliminating the need for separate directional use and reducing operator difficulty and the risk of misoperation.

[0016] The L-shaped gauge has two inner surfaces. A groove with a depth of c is opened on the inner surface. Two symmetrical vertical grooves with a width of d are opened along the center line of the groove. The distance between the center of the vertical groove and the inner end face is a.

[0017] Based on the product's structural characteristics, the welding positioning surfaces A and B of the lower connecting plate 3 are used as reference surfaces. A groove is designed for the gauge at the weld location. Since the dimensions from end face A of the lower connecting plate 3 to the first weld 4 and from end face B of the support leg 1 to the second weld 5 are consistent, it is ensured that the center position a of the groove is consistent with the center position of the long weld (e.g., ...). Figure 2As shown in the figure, dimension a is consistent with the dimension from end face A of the lower connecting plate 3 to the first weld 4 and the dimension from end face B of the support leg 1 to the second weld 5; dimension c needs to take into account the weld reinforcement height, and must ensure that dimension C is greater than the weld reinforcement height and is easy to observe. The farther away from the weld, the less favorable it is for weld observation. Therefore, dimension C is the weld reinforcement height + 1.5mm; dimension d is the groove width for observing the weld, and this groove width must be less than the weld width; dimension e is the groove depth. Grooves are cut on both sides of the gauge (i.e., grooves are cut on both surfaces of gauge E and F), which can be detected from two directions, making it easy to observe the weld; dimension f ensures the vertical accuracy of the inspection surface and also ensures the accuracy of the weld position of the product.

[0018] To address the challenge of determining whether electron beam weld position deviation after lower tube seat welding requires destructive testing, a weld position gauge was designed to enable non-destructive weld position inspection, improving the reliability of product weld positions. The L-shaped structure design eliminates directional usage issues and provides a higher degree of fit to the workpiece.

[0019] The method of using this utility model is as follows:

[0020] When inspecting the first weld 4, press the inner wall B of the L-shaped gauge firmly against the end face of the lower connecting plate 3. When inspecting the second weld 5, press the inner wall B of the L-shaped gauge firmly against the end face of the support leg 1. Observe the corresponding position of the other L-side weld, i.e., dimension a. Observe that the center position of the weld is consistent with the center position of dimension d, with a deviation not exceeding 0.5mm. After inspection, remove the L-shaped gauge.

Claims

1. A device for detecting the alignment of the weld seam of the lower tube seat of a fuel assembly, characterized in that: The gauge includes an L-shaped overall design. The L-shaped gauge has two inner surfaces with grooves of depth c on the inner surfaces. Two symmetrical vertical grooves of width d are cut along the center line of the grooves. The distance a between the center of the vertical grooves and the inner end face is a. The distance a is consistent with the dimension from the end face A of the lower connecting plate to the first weld and the dimension from the end face B of the support leg to the second weld. The distance c is the weld reinforcement height + 1.5mm. The distance d is the groove width for observing the weld, which is less than the weld width.

2. The device for detecting the alignment of the weld seam of the lower tube seat of a fuel assembly as described in claim 1, characterized in that: The L-shaped gauge is machined in one piece using heat-treated Cr12MoV material.

3. The device for detecting the alignment of the weld seam of the lower tube seat of a fuel assembly as described in claim 1, characterized in that: The L-shaped gauge is designed in the same direction in both directions.

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