Structure seamless steel pipe for general structure and mechanical structure with seamless steel pipe (GB/T8162-1999). GB/T8162-- Chinese National Standard ASTM A53 - for Testing and Materials Institute Standards ASME SA53 - American Boiler and Pressure Vessel specification uses for the manufacture of pipes, containers, equipment, pipe fittings and mechanical structure with seamless steel pipe steel grades 10 , 20,35,45, Q345, 15CrMo, 12Cr1MoV, A53A, A53B, SA53A, SA53B