Core Bits

In diamond wireline drilling, NQ, HQ, and PQ core bits are the sacrificial cutting tools at the very end of the drill string. They are engineered to grind away rock, leaving a cylindrical “core” that passes into the barrel for recovery.
Core Bit Anatomy
The Matrix: The “crown” or cutting face of the bit, made of a blend of metal powder and industrial diamonds. As the matrix wears away, it exposes new, sharp diamonds.
Waterways: Channels cut into the bit face that allow drilling fluids to cool the bit and wash rock cuttings (sludge) away from the cutting surface.
Gauges: The bit has an “ID” (Inside Diameter) to set the core size and an “OD” (Outside Diameter) to maintain the borehole size.