Skill requirements and inspection of high frequency welded pipe

The nominal diameter of the welded pipe is 6~150mm, the nominal wall thickness is 2.0~6.0mm, and the length of the welded pipe is generally 4~10 meters, according to the rules of the GB3092 Welded Steel Pipe for Low-Pressure Fluid Conveyance. It can be delivered according to fixed-length or multiple lengths. The surface of the steel pipe should be lubricated, and no defects such as folding, cracks, delamination, lap welding, etc. are allowed. The surface of the steel pipe is allowed to have minor defects such as scratches, scratches, weld misalignment, burns, and scars that do not exceed the negative deviation of the wall thickness. Thickening of the wall thickness at the weld and the presence of internal weld bars

And to meet the requirements of the standard rules. Steel pipes should be able to withstand certain internal pressure, and welded steel pipes should be subjected to mechanical function tests, flattening tests, and surface expansion tests. Perform a 2.5Mpa pressure test when needed, and there will be no leakage for one minute. Answer Use the method of eddy current flaw detection instead of a hydraulic test. Eddy current flaw detection is carried out by the GB7735 Steel Pipe Eddy Current Inspection Method. The method of eddy current flaw detection is to fix the probe on the frame, and keep the interval between the flaw detection and the welding seam 3~5mm, and carry out specific scanning of the welding seam by the rapid movement of the steel pipe. The flaw detection signal is automatically processed and automatically processed by the eddy current flaw detector. Sorting to reach the target of flaw detection.