PDC Drill Bit, Tricone Drill Bit, Tricone Hole Opener manufacturer / supplier in China, offering Rock Drill Bit 9 -1/2 " Milled/Steel Tooth Tricone Drill Bit, Oil Drilling Tool 17-1/2"Inch IADC 545 Tricone Drill Bit, TCI Roller Cone Bit 12-1/4 " Tricone Drill Bit IADC535 and so on.