Check out these pics of the Tenaris Siderca plant in Buenos Aires, Argentina showing the various steps involved in order to produce steel seamless pipe:
http://www.msm.cam.ac.uk/phase-trans/2005/a37/a37b.htmlThese picture are from the phase Transformation Group of the Material Sciences Department of the University of Cambridge UK... Harry's in some of the pics. ;)
Enjoy!
Respectfully,
Henry