ANSI B16.9 DIN 2616-1, 2616-2 EN 10253-1 Up to 16” N.B. all schedules Carbon steel: ASTM/ASME SA234 WPB, WPC, WPL6 Alloy steel: ASTM/ASME SA234 WP5, WP9, WP11, WP12, WP22, WP91