1.OD:2 3/8"-6 5/8" 2.Grade:E,X,G,S 3.Upset:IU,EU,IEU 4.HB:Arnco100XT,150XT, ... region ensures the drill pipes are of no defects. All threads are machined by CNC Lathes and inspected with ... -resistance during initial break-in and drilling operation, all threads are also phosphated or coppered, and all the roots are cold ... , OHSAS 18001, Arnco Hardbanding Certificates and so on. 2 3/8--5 1/2 drill pipe