A method for processing metal loss defects in pipeline girth welds

Abstract

The invention relates to a processing and manufacturing method of pipeline girth joint metal loss defect. The method comprises the following steps: cutting a plurality of sections of small pipelines with an equal length from a standard pipeline by a high-pressure water jet, cutting the two ends of each small pipeline into V-shaped grooves with a standard length, and welding two small pipelines together so as to form a plurality of small pipelines with standard girth joint; marking center positions and defect lengths of girth joint defects to be processed on the inner surface, outer surface, side wall, and center position of each girth joint of the small pipelines, cutting a small notch on the position of a defect to be processed, then gradually grinding and cutting the marked position along the small notch until the depth reaches a required depth; repeating the steps mentioned above until defects of other small pipelines with a girth joint are produced, and finally connecting all small pipelines together. The method provides data support for pipeline inner detector performance index verification and calibration and is capable of improving the reorganization rate and size quantification precision of pipeline inner detector on detecting pipeline girth joint metal loss defect.

Description

technical field [0001] The invention relates to a manufacturing method for metal loss defects in pipeline girth welds. It relates to the technical field of piping systems. Background technique [0002] In-pipeline detection can detect the defects of oil and gas pipelines under the normal operation state of the pipeline, provide scientific basis for the prevention, repair and maintenance of pipeline accidents, and play an important role in ensuring the safe operation of pipelines. The pull test of the pipeline with defects is the basic method for the calibration and performance index verification of the internal detector, and it is a success to process defects of different positions, types and sizes that meet the calibration and verification requirements of the detector on a pipe with a specific diameter and wall thickness. The key to conducting a pull test. [0003] At present, the electrochemical corrosion method is generally used in engineering to process corrosion defec...

AI Technical Summary

Problems solved by technology

For metal loss defects in girth welds, due to their special location and high dimensional accuracy requirements, there are no mature and reliable processing methods at home and abroad for reference, which limits the application of pull tests for metal loss defects in girth welds. As a result, it is impossible to effectively verify the detection probability and recognition accuracy of various internal detectors for different types and sizes of girth weld metal loss defects, and it is also impossible to establish a size judgment model for girth weld metal loss defects, which restricts the pipeline girth welding Seam Metal Loss Defect Detection

CN102950444A discloses a method for processing metal defects in pipeline spiral welds, but this method is not ideal

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