... WELD) 2.WT:SCH10-160 3.Material:SS,CS,Alloy 4.Type:ERW,LASW,eg 5.Certificate:API,ISO,CE ... pipeAPI 5LA,B,X42,X46, X52,X56,X60,egStraighe seem steel pipegeneral structure stents, low voltage liquid transportation, etc GB/ ... T13793-1992GB3091-2001Q235BQ345BSpiral steel pipelow voltage liquid transportation with steel pipesSY/T5037-2000Q235BQ345B ASTM SA335 A335,P22 alloy steel pipe