Tricone Bits, PDC Bits, Drag Bits manufacturer / supplier in China, offering Rotary Tricone Rock Bits IADC517 5 3/4 Inches 146.1mm Deep Excavation Drilling, Tricone Bit IADC517 3 3/8" 85.7mm for Deep Excavation Drilling Ground Improvement, IADC447 3" 76mm Tricone Rock Bit for Mining and Geotechnical Investigation and so on.