Patent ID: 6116357
Filing Date: 2000-09-12
Classification: E21B

Abstract:
A drill bit for boring a bore hole in an earthen formation, comprising:a bit body having a pin end, a cutting end and a longitudinal bit axis and including at least two legs extending from said cutting end, each of said legs including a bearing and rotatably supporting a cutter cone on said bearing, said bit body further including a fluid flow system, including a flowway in said pin end in fluid communication with at least one exit port in said cutting end, said exit port being defined by a nozzle boss and disposed adjacent one of said legs;each of said legs including a leading side surface, a trailing side surface, and a center panel;at least one of said legs being asymmetric such that its trailing side surface is larger than its leading side surface; anda lubrication system in at least one of said legs, said lubrication system comprising a lubricant reservoir in fluid communication with said bearing, said reservoir comprising a cavity formed in said leg and having a reservoir installation opening in said trailing side surface of said leg.