Our company mainly produces drilling tools: square and hexagonal kellys, heavy weight drill pipes, spiral heavy weight drill pipes, non-magnetic integral heavy weight drill pipes, all kinds of drilling collars, lifting subs, non-excavation drill tools, cross-over subs, many kinds of high-precision manufacturing and inspection equipment: special numerical-control pipe thread lathes, large cylindrical lathes, large milling machines, deep-hole boring machine drilling, friction welding, heat treatment production line with medium frequency as well as variety of thread gauges, single measuring instruments, thickness gauges, hardness testers, ultrasonic flaw detectors, ballisticwork testing machines, universal testing machines with microcomputer displaying hydraulic pressure, and so on.