A surfacing repair method and system for weld repair of stainless steel branch pipes

Abstract

The invention provides a method and system for surfacing welding repair for stainless steel branch pipe weld maintenance, including: obtaining defect information, original data and field operation environment data of the branch pipe weld to be repaired; according to the acquired defect information of the branch pipe weld , original data and field operating environment data to formulate the overall plan for surfacing repair; according to the formulated overall plan for surfacing repair, process and surfacing the welds of the branch pipes to be repaired; inspect, test and evaluate the surfacing welds. In the present invention, by directly overlaying corrosion-resistant metal on the surface of the branch pipe weld area to be repaired, the surfacing layer of the present invention forms a new pressure boundary, realizes the structural strengthening of the branch pipe weld seam, and improves the internal residual stress state of the branch pipe weld seam and After surfacing, the area near the defect area is in a state of compressive stress, inhibiting the initiation and expansion of cracks, and ensuring that the repaired branch pipe weld meets the requirements for full-cycle safe operation.

Description

technical field [0001] The invention relates to the field of welding repair, in particular to a repairing method and system for repairing welding seams of stainless steel branch pipes. Background technique [0002] In the piping design, the branch pipe weld is a common connection method between the main pipe and the branch pipe. Among them, the welding seam structure of the placed pipe seat and branch pipe (example: BOSS head welding seam) is widely used, and its structure and manufacturing process are all mature designs, such as figure 1 shown. For small-diameter branch pipe welds, the accessibility of welding and the convenience of interlayer cleaning are poor (especially when the groove angle is small), when the welder's technical level is not good, the welding process is not properly controlled, and there is a lack of effective detection methods , it is easy to produce defects such as slag inclusion, lack of fusion, and pores, which become the source of failure. Durin...

AI Technical Summary

Problems solved by technology

Evaluation without treatment is based on defect detection information, mechanical integrity analysis is carried out, and the safety of the pipeline with defects is evaluated under the condition of no treatment. This scheme needs to obtain accurate defect information, otherwise only qualitative evaluation can be carried out, and the defects of this method always exist , there is a further risk of failure under the action of external conditions

However, for branch pipe welds, the shape of the saddle-shaped transition area is complex, and the automatic welding method has not yet been implemented for the surfacing repair of branch pipe welds.

[0004] In summary, the existing maintenance methods have some technical limitations, and in some cases (such as the defect has penetrated and the medium in the pipe cannot be emptied, the pipeline system cannot be isolated, etc.), the above maintenance methods cannot be effectively implemented

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