STEEL PIPES AND TUBES Structural Steel Pipes Size OD 21.3mm-609.6mm Standard ASTM A500 GB/T 3091 Steel Grade GR-A, GR-B, Q195, Q235, Q345, Q420, Q460 ERW & Seamless Pipes Size ½" NB - 16" NB Standard API 5L GB/T 9711 Steel Grade ASTM A-53 A-135 A-500, A-513, A-523, A-847 A-984 API 5L IS-1161 1239, 1978, 3589 BS-1387, BS-1339 & DIN. Galvanised Pipes Size OD 21.3mm-609.6mm Standard IS 1239. BS 1387 ASTM A53 Steel Grade GR-A, GR-B, Q195, Q235, Q345, Q420, Q460 Square & Rectangular Tubes Size SHS 12X12 - 250X250 RHS 40X20 - 250X100 Standard JIS G3466, S355 J2H EN 10025 Steel Grade GR-A, GR-B, Q195, Q235, Q345, Q420, Q460