HYBRID DRILL BIT WITH HIGH PILOT-TO JOURNAL DIAMETER RATIO

摘要

The invention disclosed and taught herein is directed to an improved hybrid drill bit and associated elements having at least two rolling cutters, each rotatable around separate spindles on the bit, and at least one fixed blade. The improved drill bit expands the pilot pin to journal diameter ratio within the body of the rolling cutter, but within the confines of the allowable space of the rolling cutter.