... 3. Welding Type: 1) Seamless Steel Pipe, 2) Seamed/Welded Steel Pipe: ERW Steel Pipe, Spiral Steel Pipe 4. Material: Carbon Steel: ASTM A106 Gr ... . B, ASTM A53, Gr. B, ASTM A105, ASTM A234 Line Pipe ... contract, according to the real order quantity ASTM A53 API5l ERW Steel Pipe