SYSTEM, METHOD, AND APPARATUS FOR VARIABLE JUNK SLOT DEPTH IN DRILL BIT BODY TO ALLEVIATE BALLING

摘要

An earth boring drill bit design for alleviating balling varies the junk slot depth in junk slots subject to balling from the other junk slots. At least one of the junk slots 39 is defined as a primary junk slot 39c and has a junk slot depth Dp in an axial direction that is greater than the depths D of the other junk slots 39a, b. Using variable depth bit bodies enhances the hydraulic characteristics of the bit as well as assists in the placement of the nozzles for machining purposes. This flexibility optimizes the area changes along the ducts required by the bit's operation.