... processing according to customer requirements.OD:88.9mm,73mm Drill wells for the 88.9mm diameter, threaded at both ends, you ... joint, R780 35CrMo material with material of the tool joint. Our factory has the largest drill in northern China, joint production line, ... of CNC lathes, special testing equipment, manufacture of drill pipe to meet the geological, geothermal, wells, oil drilling and other ...