A rotary drill tool for cutting rock includes at least one journal leg mounting a spindle and a respective rotary cone cutter. The spindle includes a plurality of fluid distribution passageways arranged to provide a supply of a cooling and cleaning fluid to the bearing assembly. Vent holes are provided through the cutter to allow an exhaust flow of fluid and an annular seal is provided at a base region of the spindle to maintain a positive fluid pressure within the cutter cavity to prevent dust and dirt ingress.

Bearing systems configured for use on a downhole tool may include a tensioner bolt having a complementary nut, the tensioner bolt and nut sized and shaped to secure the rolling cutter member to a head. A radial bearing may include an annular sleeve sized and shaped to surround the head. A shaft washer may be sized and shaped to surround the head between an enlarged head of the tensioner bolt and the annular sleeve. A bearing element may be configured for positioning proximate the head, the bearing element comprising an upper surface configured for sliding, frictional contact with a lower surface of the shaft washer.

Disclosed herein is a pressure compensation system for a bottom hole assembly. The disclosed pressure compensation system improves the responsiveness of a hydraulically actuated component carried by the bottom hole assembly.

Disclosed herein is a pressure compensation system for a bottom hole assembly. The disclosed pressure compensation system improves the responsiveness of a hydraulically actuated component carried by the bottom hole assembly.

An example drill bit is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The drill bit includes a drill bit body including at least one leg. The drill bit may include at least one roller cone rotatably mounted on the drill bit body. The roller cone includes a plurality of cutting elements for abrading or crushing rock. The drill bit includes at least one bearing mounted between a surface of the drill bit body and the at least one roller cone to facilitate rotation of the at least one roller cone. The drill bit system includes a lubrication system to reduce friction between moving parts of the drill bit. The drill bit system includes at least one wear sensor associated with the drill bit to sense physical wear on the drill bit.

An example drill bit is configured to operate within a wellbore of a hydrocarbon-bearing rock formation. The drill bit includes a drill bit body including at least one leg. The drill bit may include at least one roller cone rotatably mounted on the drill bit body. The roller cone includes a plurality of cutting elements for abrading or crushing rock. The drill bit includes at least one bearing mounted between a surface of the drill bit body and the at least one roller cone to facilitate rotation of the at least one roller cone. The drill bit system includes a lubrication system to reduce friction between moving parts of the drill bit. The drill bit system includes at least one wear sensor associated with the drill bit to sense physical wear on the drill bit.

The disclosure relates to a bore tube for a pressure compensation system in a roller cone drill bit. The bore tube includes a bit body having at least one support arm extending therefrom, a lubricant chamber in each support arm, a bore in each support arm extending from to the lubricant chamber to an exterior surface of each support arm, a tube in the bore of each support arm, and a floating bead in the tube and operable to move axially within the tube in response to a pressure of the environment surrounding the roller cone drill bit.

The disclosure relates to a bore tube for a pressure compensation system in a roller cone drill bit. The bore tube includes a bit body having at least one support arm extending therefrom, a lubricant chamber in each support arm, a bore in each support arm extending from to the lubricant chamber to an exterior surface of each support arm, a tube in the bore of each support arm, and a floating bead in the tube and operable to move axially within the tube in response to a pressure of the environment surrounding the roller cone drill bit.

Disclosed herein is a pressure compensation system for a bottom hole assembly. The disclosed pressure compensation system improves the responsiveness of a hydraulically actuated component carried by the bottom hole assembly.

A cutter for a boring head having a shaft is mountable at a saddle. A roller body is rotatably mounted about the shaft via bearings housed at a cavity located radially between the shaft and the roller body. A lubrication fluid is configured to flow internally within the shaft via a first and second passageway. An elongate overflow chamber is provided in fluid communication with the passageways to receive thermally expanded lubrication fluid from the cavity.