Unlock instant, AI-driven research and patent intelligence for your innovation.

Repair method for stainless steel pipeline weld joint

A technology for stainless steel and pipes, applied in welding equipment, tubular objects, arc welding equipment, etc., can solve the problems of reducing the qualified rate of repair and increasing the workload, and achieve the effect of improving the qualified rate of repair, easy welding, and simple method

Pending Publication Date: 2021-08-03
CHINA NAT CHEM ENG THIRD CONSTR
View PDF5 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

However, this method is prone to new welding defects during the repair process, which not only reduces the qualified rate of repair, but also increases the workload

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Repair method for stainless steel pipeline weld joint

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0028] Such as figure 1 Shown, a kind of repair method of stainless steel pipeline 1 weld seam, comprises following repair steps:

[0029] S1. Open the skylight 2 at the flat welding position opposite to the weld defect position of the stainless steel pipe 1. The skylight 2 is formed by grinding the weld seam of the stainless steel pipe 1 with a grinder, and the width of the skylight 2 is 3-5mm, and the length is suitable for visual observation ;

[0030] S2. The tungsten electrode 3 is ground and loaded into the high-frequency argon tungsten arc welding torch 4. It is advisable that the length of the tungsten electrode 3 is greater than the outer diameter of the stainless steel pipe 1 by 50mm. 3 One end is inserted from the skylight 2 into the position 5 of the upward welding defect inside the stainless steel pipe 1. At this time, mark on the tungsten electrode 3 that is in contact with the root of the flat welding groove at the skylight 2, and use a flame-retardant adhesive...

Embodiment 2

[0036] The difference from Example 1 is that the inner cavity of the stainless steel pipe 1 corresponding to both sides of the weld is sealed with water-soluble paper. Water-soluble paper is a sealing material for welding shielding gas, also known as water-soluble paper, soluble paper or easily soluble paper. The paper is mainly composed of carboxymethyl cellulose sodium salt. It is alkaline, white, odorless, and has strong moisture absorption. It can swell and gelatinize in neutral or alkaline aqueous solution, and can be dispersed in in the water. When the water-soluble paper is used for sealing, the operation is more convenient than the sponge 7, and it can be directly kneaded into a ball for sealing.

[0037] In the bottom welding process of the stainless steel pipe 1, if it is found that defects such as unfused, undercut, sag, and welding wire head appear at the root of the inner mouth from the supine welding to the vertical welding position, it is not necessary to polish...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

PropertyMeasurementUnit
lengthaaaaaaaaaa
Login to View More

Abstract

The invention relates to a repair method for a stainless steel pipeline weld joint. The repair method comprises the following repair steps of S1, forming a skylight in the flat welding position opposite to the weld joint defect position of a stainless steel pipeline; S2, driving a tungsten electrode to be inserted into the overhead welding defect position in the stainless steel pipeline by a high-frequency tungsten electrode argon arc welding gun from the skylight, and pulling out the tungsten electrode after a mark is made on the tungsten electrode making contact with the flat welding position; S3, blocking the weld joint defect position, the skylight and stainless steel pipeline inner cavities corresponding to the two sides of the weld joint through blocking structures to form a closed chamber, and carrying out argon filling protection; S4, opening the blocking structure at the skylight, inserting the tungsten electrode into the overhead welding defect position from the skylight for arc starting welding, and repairing the weld joint; and S5, after the skylight is welded and blocked, disassembling all the blocking structures, carrying out weld joint nondestructive testing, and completing the whole repair process. The method is simple, convenient and efficient, the repair percent of pass is high, and the problems that due to the fact that the defect appearing from overhead welding to the root of a vertical welding inner opening needs to be worn through from the outer side to the inner opening for repair, labor and time are wasted, and the repair percent of pass is low are solved.

Description

technical field [0001] The invention belongs to the field of engineering welding, and in particular relates to a method for repairing weld seams of stainless steel pipes. Background technique [0002] Stainless steel pipes are common pipes in petrochemical plant process pipes. Argon arc welding is generally used for bottoming and manual arc welding for filling and covering. On-site large-thickness pipes are restricted by conditions and cannot rotate fixed welds. In the process of argon arc welding, the welding position is affected, and the bottoming weld is more prone to undercut, incomplete fusion, and depression from the position of overhead welding to vertical welding. and other defects. [0003] The conventional repair method for this kind of internal root defect is to grind through from the outside to the root of the pipe weld, then re-prime, and then fill the cover. However, this method is prone to new welding defects during the repair process, which not only reduces...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): B23K9/167B23K9/235
CPCB23K9/167B23K9/235B23K2101/06B23K2103/05
Inventor 张旗
Owner CHINA NAT CHEM ENG THIRD CONSTR