Purchase situation of straight seam steel pipe

Purchase situation of straight seam steel pipe

The nominal diameter of the welded pipe is 6~150mm, and the nominal wall thickness is 2.0~6.0mm. The length of the welded pipe is usually 4~10 meters. The surface of the steel pipe should be smooth, 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, dislocation of welds, burns, and scars that do not exceed the negative deviation of the wall thickness. Allow wall thickness increase at the weld and the presence of internal weld ribs. Welded steel pipes shall be subjected to mechanical performance test, flattening test, and flaring test, and shall meet the requirements of the standard. The steel pipe should be able to withstand the internal pressure, and carry out the 2.5Mpa pressure test, and keep it without leakage for one minute. The eddy current flaw detection method is allowed to replace the hydraulic test. Eddy current flaw detection is carried out following the standard of "Steel Pipe Eddy Current Test Method". The eddy current flaw detection method is to fix the probe on the frame, keep the distance between the flaw detection and the weld 3~5mm, and perform a comprehensive scan of the weld by the rapid movement of the steel pipe. The flaw detection signal is automatically processed and automatically sorted by the eddy current flaw detector. To achieve the purpose of flaw detection. After flaw detection, the welded pipe is cut to the specified length with a flying saw and is rolled off the assembly line through the overturning frame. Both ends of the steel pipe should be flat-headed and chamfered, and the mark should be printed.