... #,20#,45#,16Mn, 2ASTM A106 Gr.B, ASTM A53 Gr.B, St 37, St 42, St 52, Q 235, Q 195, ... Q345, 27SiMn 30 inch seamless steel pipe 10#,20#,45#,16Mn, ASTM A106 Gr.B ... , ASTM A53 Gr.B, St 37, St 42, St 52, Q 235, Q 195, ... tubes foroil casing andtubing in oil wellsAPE SPEC 5LA, B, X42APISeamles Steel Tubesand Pipes forHigh Pressure BoilerGB5310-199520G, ...