1.seamless steel pipe ,Boiler pipe 2.OD:20mm--820mm, 1/2"--32" 3.Steel ... .0,st44.0,ST35.8,ST45.8,Gr320Executive StandardGB3087-1999,GB5310-1995,ASTM A106,ASTM A179ASTM A192,DIN 1629- ... 1984,DIN 17175,BS3059.1-1987Application:structure steel pipe,boiler pipe,petroleum,gas.Our quality policy:Facilitating quality,Servicing honesty ... ,Best service. ASTM A179 Carbon Boiler Seamless steel pipe(1/2''-32'')