PDC Drill Bits, Tricone Bits, DTH Hammer manufacturer / supplier in China, offering Steel Milled Tooth Bit 14 3/4" 18 1/2" 19" 20" API Tricone Bit/ Rock Drill Bit/ Roller Cone Bit for Water/Oil/Gas Well Drilling, Drilling Tools, Stable IADC S433 215.9mm PDC Oil Drill Bit for Limestone Anhydrite, High Efficiency IADC S423 444.5mm PDC Oil Drill Bit for Shale Sandstone and so on.