Tricone drilling is another method used to drill into bedrock. PML Field Services & Soil Investigations carry a variety of different styles and sizes of tricones.
A tricone bit has three conical rollers with teeth made of a hard material, such as tungsten carbide. The teeth break rock by crushing as the rollers move around the bottom of the borehole.These drill bits have openings that allow for the expulsion of air or drilling fluids, at high velocity and high pressure to help clean the bit and, for softer formations, help to break apart the rock.
A polycrystalline diamond compact (PDC) bit has no moving parts and works by scraping the rock surface with disk-shaped teeth made of a hard material, such as tungsten carbide or diamond.