CN112756859B

CN112756859B - Method for confirming gap between end plug and inner welding seam of cladding tube

Info

Publication number: CN112756859B
Application number: CN202011612226.9A
Authority: CN
Inventors: 鲁杭杭; 冯海宁; 姬鹏波; 张洲峰; 郭庆祥; 董秋实; 赵瑞瑞
Original assignee: China North Nuclear Fuel Co Ltd
Current assignee: China North Nuclear Fuel Co Ltd
Priority date: 2020-12-30
Filing date: 2020-12-30
Publication date: 2023-03-21
Anticipated expiration: 2040-12-30
Also published as: CN112756859A

Abstract

The invention belongs to the technical field of nuclear fuel element manufacturing, and particularly relates to a method for confirming a gap between an end plug and a welding seam in a cladding tube. Step one, processing a hollow graduated scale: controlling the width of the graduated scale to be more than 2mm smaller than the inner diameter of the cladding tube, and controlling the length of the graduated scale to be 10-20mm; the width of the hollow part of the graduated scale is 2 plus or minus 1mm, and the length is 5-10mm; the distance between two adjacent graduation lines is 0.1mm; step two, inserting the graduated scale into the cladding tube; the welding seam is in the hollow part of the scale; step three, checking the gap of the welding seam: an endoscope is adopted to see the weld gap through the hollow part of the graduated scale; slowly moving the graduated scale axially; if the gap between the end plug and the welding seam in the cladding tube is in the two adjacent scale marks, the gap between the welding seams is smaller than 0.1mm; if the gap between the end plug and the welding seam in the cladding tube exceeds two adjacent scale marks, the gap between the welding seams is larger than 0.1mm. The workpiece with the gap between the end plug and the welding seam in the cladding tube larger than 0.1mm is removed through the inspection of the gap between the end plug and the welding seam in the cladding tube before welding, so that the welding yield is improved.

Description

Method for confirming gap between end plug and inner welding seam of cladding tube

Technical Field

The invention belongs to the technical field of nuclear fuel element manufacturing, and particularly relates to a method for confirming a gap between an end plug and a welding seam in a cladding tube.

Background

In the manufacturing of nuclear fuel elements, the end plug and the cladding tube are welded outside the tube, and the gap between the welding seams of the end plug and the cladding tube can be directly observed visually without other tools. The welding seam in the end plug and the cladding tube cannot be directly observed by a visual method before welding, and the gap between the welding seam of the end plug and the cladding tube needs to be observed by other methods, so that the gap between the welding seam of the end plug and the cladding tube can be inspected.

Disclosure of Invention

Before welding the end plug and the cladding tube, the gap between the end plug and the cladding tube needs to be ensured to be less than 0.1mm, but the gap between the end plug and the inner welding seam of the cladding tube cannot be directly observed visually. The method is used for checking the state of the gap between the end plug and the inner welding seam of the cladding tube before welding, eliminating the workpiece with the gap between the end plug and the inner welding seam of the cladding tube being larger than 0.1mm, and ensuring that the gap between the end plug and the inner welding seam of the cladding tube before welding is smaller than 0.1mm. A hollow graduated scale is designed and processed, and the inspection of the gap between the end plug and the weld joint in the cladding tube before welding is realized under the condition that a vision camera which is amplified by 10 times is matched.

In order to achieve the purpose, the technical scheme adopted by the invention is as follows:

a method for confirming the gap between an end plug and a welding seam in a cladding tube,

step one, processing a hollow graduated scale

1. Controlling the width of the graduated scale to be more than 2mm smaller than the inner diameter of the cladding tube, and controlling the length of the graduated scale to be 10-20mm;

2. the width of the hollow part of the graduated scale is 2 plus or minus 1mm, and the length is 5-10mm;

3. the distance between two adjacent graduation lines is 0.1mm;

step two, inserting the graduated scale into the cladding tube; the welding seam is in the hollow part of the scale;

step three, checking the gap of the welding seam

1. An endoscope is adopted to see the weld gap through the hollow part of the graduated scale;

2. slowly moving the graduated scale axially;

3. if the gap between the end plug and the welding seam in the cladding tube is in the two adjacent scale marks, the gap between the welding seams is smaller than 0.1mm;

4. if the gap between the end plug and the welding seam in the cladding tube exceeds two adjacent scale marks, the gap between the welding seams is larger than 0.1mm.

And marking scale marks by using a milling machine.

The beneficial effects obtained by the invention are as follows:

by checking the gap between the end plug and the welding seam in the cladding tube before welding, workpieces with the gap between the end plug and the welding seam in the cladding tube larger than 0.1mm are removed, and the welding yield is improved.

Drawings

FIG. 1 is a schematic view of an outer weld of an end plug to a cladding tube;

FIG. 2 is a schematic view of a weld in the end plug and cladding tube;

FIG. 3 is a schematic view of a scale;

FIG. 4 is a schematic view of a weld gap in the inspection tube;

in the figure, 1, a cladding tube, 2, an end plug, 3, a graduated scale, 4, a weld gap inside a tube, 5, a weld gap outside the tube, 6, the distance between two adjacent graduated lines, 7, a hollow part and 8 are graduated lines.

Detailed Description

The invention is described in detail below with reference to the figures and the specific embodiments.

Step one, designing and processing hollow graduated scale

2. the width of the hollow part is 2 plus or minus 1mm, and the length is 5-10mm;

3. dividing scale marks by a milling machine, wherein the distance between two adjacent scale marks is 0.1mm;

and step two, inserting the graduated scale into the cladding tube.

1. The relative positions of the welding line and the graduated scale are as follows: the weld is in the hollow.

Step three, checking the gap of the welding seam

1. The endoscope is adopted, and the welding seam gap can be seen through the hollow part of the graduated scale.

2. The scale is slowly moved axially.

Claims

1. A method for confirming a gap between an end plug and a weld joint in a cladding tube is characterized by comprising the following steps:

step one, processing a hollow graduated scale

3. the distance between two adjacent graduation lines is 0.1mm;

secondly, inserting the graduated scale into the cladding tube; the welding seam is in the hollow part of the scale;

step three, checking the gap of the welding seam

2. slowly moving the graduated scale axially;

3. if the gap between the end plug and the welding seam in the cladding tube is in the two adjacent scale marks, the gap between the welding seams is less than 0.1mm;

2. The method of confirming a weld gap in an end plug and cladding tube of claim 1, wherein: and marking scale marks by using a milling machine.