Oil Line Pipes 1.Standard:BS, GB, DIN, ASTM, API 2.Grade: ... ), St37, St52, St42, Q.. 3.Outer Diameter:8-24mm Oil Line Pipes Spiral Seam double-side submerged arc welded steel pipe1 ... . Technique SAW welding Usage1. Piling project2. heat-supply project 3. conveying water, coal gas, drainage and other Low and middle pressure ... 6. Oil tube 7. hot-galvanized steel pipe Ssaw Oil Line Pipes (L415, L320, L450)