ERW325 H.F. Straight Welded Pipe Production Line ERW325 high frequency longitudinal welded pipe production line / pipe making machine / tube mill is designed to produce welded pipes of 140mm-325mm in OD and 4.0mm-12.7mm in wall thickness, as well as corresponding square and rectangular pipe. Products: architectural structure pipes, API pipes, tower footing tubes, automobile beam steel pipe and other products. Equipment advantages ZTF forming process save roller up to 60% With direct square forming technology, one set of roller can produce all pipe sizes Electric control and automatic adjustment, high precision,high roller change speed