high wear-resisting ,aging resistant , service life is long,high security, highly pressurized, widely used Typeseamless steel pipe spiral steel pipe alloy pipe welded pipe stainless steel pipeStandardASTM A106 GRB/API5LGRB/ASTMA53GRB DIN ANSI GB SH HGMaterialGRB20#STEEL,A3,A234,ASTM,Q235,Q345,10#,45#,12CrMo,1Cr18Ni9Ti,15CrMn,0Cr18Ni9,ST37,00Cr19Ni10,16MnR,Cr5Mo,15CrMo, etcOD1/4''-24'',13mm- ...