Drill bit (well)

A Drill bit, is a device attached to the end of the drill string that breaks apart, cuts or crushes the rock formations when drilling a wellbore (water, gas or oil).

The drill bit is hollow and has jets to allow for the expulsion of the drilling fluid at high velocity and high pressure to help clean the bit and help to break apart the rock (for softer formations).

See Drilling rig (petroleum) for a diagram of a drilling rig.

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  Typical tri-cone rock bit
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  Tricone rock bit (medium worn-out)
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  PDC bit for well drilling
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  Multiple Tricone (carbide) insert Bits
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  Tricone (carbide) insert Bit
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  Tricone rock Bit
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  Damaged Drill Bit, broken carbide inserts