Big Diameter LSAW Welded Pipe OD 325--1200mm WT 8--80mm Certificate ISO ... and API Surface treatment oil coated Big diameter steel pipe(LSAW)StandardsGB/T3091-2008,GB/T9711.1, API5L etc ... , ASTM A53GrB,L245, X42-X70,API5L GrB, etc.ApplicationsStructural pipe, liquid transportation, conveyance of oil and gas, petroleum transportation ... the customers ' requirements.Certificate: Big Diameter LSAW Welded Pipe