Apparatus and method for downhole lubrication replenishment
Automatic depth compensating device
Automatic depth compensating system for drill bit lubrication
Bellows lubricant pressurizer for sealed bearing rock bits
Biased lubricant compensator for an earth boring drill bit
Bit with ball plug compensator having pressure relief means
Boring apparatus
Combination seal and pressure relief valve for sealed drill stri
Compact roller cutter
Compensator for earth boring bits
Compressible pressure compensator within closed lubricant volume
Cutter actuated rock bit lubrication system
Disc cutter and excavation equipment
Drill bit and drill assembly
Drill bit assembly
Drill bit lubricant circulation system
Drill bit lubrication system
Drill bit reservoir with controllable relief pressure
Drill bit with single cutting head
Drill bits for drilling wells