... and proof pressure, and are suit for Petrochemical Industry. ASTM A312 is a Standard Specification for Seamless, ... used in many area, just like pharmacy, food industry, petroleum industry, heat exchange and decoration. We manufacture the ... field: Decoration, Heat-Exchanger, Condenser Tubes, Sanitation, food industry , Petroleum and Gas Industry and Liquird Delivery.6) Surface: 180#, 400#, 600# ...