Welded Spiral Steel Pipe 1.grade:Q235,Q345,10#,20#,16Mn,L245,X80 2. ... :API,GB/T 3.OD:219-3000mm thickness:6-25mm Welded Spiral Steel Pipe1. Material:Q235,Q345,10#,20#,16Mn,L245 ... , my name is Tina, your inquiries will be highly appreciated! Welded Spiral Steel Pipe