Drilling Bit Bearings Definition & Types In TCB
Various types of Roller Cone Drilling Bit lubrication systems package are used for bearing protection. Early systems included using the drilling fluid as the lubricant, while more recent systems use greases and oils for lubrication. Drilling fluids containing abrasive solids soon proved to be a limiting factor relative to long bit runs and, as a result, are seldom used as the lubricant in present-day bits. 

Types
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