API 5L Psl1 Casing Seamless Line Steel Pipe 3PE for Petroleum/Natural …
API 5L Psl1 Casing Seamless Line Steel Pipe 3PE for Petroleum/Natural Gas Production process of API carbon steel seamless petroleum pipeline:Round tube billet - heating - perforation - beading - annealing - pickling - painting (copper plating) - multi-pass cold drawing (cold rolling) - heat treatment - straightening - hydraulic test (flaw detection) …