... 've been exploring and developing upon producing various oil drilling tools including Drill Pipe, Drill Collar, Heavy Weight Drill Pipe, ... cold rolled. The products shall be equipped with pressed steel or plastic steel thread protectors on the connections. Drill pipes of ... -1, NS-1. RUSSIA RTN, RUSSIA GOST-R, ISO 9001,ISO 14001, OHSAS 18001, Arnco Hardbanding Certificates and so on. 2 3/8--5 1/2 drill ...