Tricone Bit, Drill Bit, PDC Bit manufacturer / supplier in China, offering API 7-1 Standard 8-1/2 Inch PDC Bit with 4 Blades for Oil Petroleum Water Mining Rock Well Drilling Diamond Bits, API 7-1 Standard 8-1/2 Inch PDC Bit with 4 Blades for Oil Petroleum Water Mining Rock Well Drilling Tools Diamond Drilling Bits Part If Oilfield Well Drilling, 12 1/4 Inches Steel Body PDC Bits with 16mm Cutters and 5 Blades for Soft to Medium Hard Formations and so on.