... various of different fields,mining,hydrology,subterranean heatpilling,water well drilling and oil well drilling.This type of bits have optimal bearing ... Drill bits, Drill Pipe, TCI tricone bits, PDC bits, PDC Diamond drill bits, roller rock bits,core bits,all size bits in oilfield,water well ... and so on. Thus the stable supplies, the quality as well as the flexible ways doing business can be reached.We ...