... :R1,R2,R3 Quality Standard 1. ASTM A 53 Standard Specification for Pipe, Steel, Black and Hot-Dipped, Zinc-Coated, Welded ... strength,Elongation), Technical Properties (Flattening Test, Flaring Test, Bending Test, Hardness Test, Blow Test, Impact Test etc), Exterior Size InspectionUsageApplicable to ...