Cutting element and drill bit for drilling soft plastic formations

摘要

A cutting element and drill bits so equipped particularly suited for drilling subterranean formations exhibiting a superabrasive cutting face with at least a portion of extremely low surface roughness, by way of example on the order of a polished, mirror-like finish. The cutting face includes a peripheral cutting edge adjacent the low surface roughness portion of the cutting face for engaging a subterranean formation, the cutting edge being of sharp configuration and essentially defining a line of contact with the formation lying between the cutting face and a side surface of the cutting element extending rearwardly therefrom. In certain formations, particularly soft, plastic formations, the drill bits equipped with the inventive cutting element may be employed as a system and method with drilling fluids modified to maintain the integrity of formation cuttings by stabilizing and locking in reactive clays present in the rock to inhibit bit balling and facilitate hydraulic cuttings removal from the bit face.