IMPROVED ROTARY CONE BIT FOR CUTTING REMOVAL

摘要

An improved rotary cone bit includes a threaded end on a bit body for coupling to a drill string. The drill bit body includes two or more leg portions extending from one end thereof. From interval at each of the leg portions is a bearing pin that extends inwardly toward the longitudinal axis of the drill bit body. On each of the bearing pins, there is rotatably mounted a cutter cone having rows of cutting teeth as a part hereof. The bit shirttail comprises a plateau extending along the longitudinal axis of the bit body in substantially the same plane as the bearing pin surface area of the shirttail.