ASTM A 268

This guide covers standard specification for a number ofgrades of nominal-wall-thickness, welded ferritic and martensitic stainlesssteel tubing for general corrosion-resisting and high-temperature service. Thesteel shall conform to the required chemical composition for carbon, manganese,phosphorus, sulfur, silicon, nickel, chromium, molybdenum, aluminum, copper,nitrogen, titanium, and columbium. The number of tubes in a lot heat treated bythe continuous process shall be determined from the size of the tubes. Thesteel shall conform to the following tensile properties: tensile strength,yield strength, and elongation. The tubes shall have a hardness number thatwill not exceed the prescribed Brinell and Rockwell hardness values. Severalmechanical tests shall be conducted, namely: tension test; flaring test (forseamless tubes); flange test (for welded tubes); hardness test; reverseflattening test; intergranular corrosion test; and hydrostatic ornondestructive electric test.