5. Pre-welding: make straight seam welded steel pipe seam after forming and using gas welding (MAG) for continuous welding; 6 in the welding: The tandem multi-wire submerged arc welding (up to four wire) in straight stitch inside of the pipe welding; 7. Welded: The tandem multi-wire submerged arc welding on the outside of LSAW steel pipe welding; The ultrasonic inspection Ⅰ: inside and outside of the straight seam welded steel pipe on both sides of the base metal and weld seam 100% inspection; 9.X-ray inspection Ⅰ: internal and external welds 100% inspection of X-ray television industry, the use of image processing system to ensure detection sensitivity; 10. flaring: for submerged arc welding straight seam steel pipe expanding the entire length of the steel pipe in order to improve dimensional accuracy and to improve the distribution of internal stress of the steel pipe; 11. The hydrostatic test: On pressure testing machine after expanding the steel pipe by-root test to ensure that the steel pipe to meet the standards required test saponification pressure seamless steel pipe, the machine has an automatic recording and storage capabilities; straight seam welded steel pipe requirements mechanical tests should be done and flattening test and flaring test, and to meet the requirements of the standard. Pipe should be able to withstand a certain internal pressure 2.5Mpa pressure test conducted, if necessary, to maintain a minute without leakage. Eddy current testing method allows to replace the hydrostatic test. Eddy current testing performed in GB7735 "pipe eddy current testing method" standard. Eddy current testing method is to probe fixed to the frame of seamless steel pipe, weld testing and keep 3 ~ 5mm distance pickling seamless steel pipe by the rapid movement of the weld comprehensive scanning, detection signal by the eddy current testing automatic processing and automatic sorting instrument to achieve the purpose of testing. After testing the required pipe length cut with flying saw, the flip-line. Both ends of the pipe should be chamfered flat head, print marks, finished hexagonal tubes tied after packaging factory. The main processing method for processing method straight pipe joints are: Forged steel: the use of a reciprocating hammer impact force or pressure to press the blank changed our desired shape and size a press molding method. Extrusion: a steel metal placed in closed extrusion Jane, pressure end of the metal from the extrusion die orifice to obtain a predetermined shape and size have finished with the processing method used for the production of non-ferrous metal sheet steel . Rolling: The steel metal blank through a gap (of various shapes) rotating rolls, due to the compression rollers so that the material cross-section is reduced, increasing the length of the press molding method. Weihai seamless steel pipe seamless steel clad dealers _ _ virtue Pipe Co., Ltd. Liaocheng by virtue of Industry. Liaocheng virtue Pipe Co., Ltd. (www.meidegc.com) (www.meidegc.com) (www.mdwfg.com) (www.mdggc.com) strong, credible, Liaocheng in Shandong steel industry has accumulated a large number of loyal customers. The company better work attitude and constantly improving innovative ideas will lead virtue of Industry and you work into the brilliant, for a better future!