Various embodiments relate to a bearing assembly including a support ring configured to reduce thermal warping under operational temperature conditions, a bearing apparatus that may utilize such a thrust-bearing assembly, and applications that incorporate the disclosed bearing apparatuses such as downhole motors in subterranean drilling systems, directional drilling systems, and many other apparatuses. In an embodiment, a bearing assembly includes a plurality of superhard bearing elements distributed circumferentially about an axis. The thrust-bearing assembly further includes a support ring having the plurality of superhard bearing elements mounted thereto. The support ring includes at least one thermal-warping-reducing feature configured to reduce a radial moment, compared to if the at least one thermal-warping-reducing feature were absent from the support ring, which is thermally induced in the support ring when the support ring and the plurality of superhard bearing elements are exposed to operational temperature conditions.

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 arrnaged 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 assemblies that include a plurality of polycrystalline diamond (“PCD”) bearing elements, bearing apparatuses including such bearing assemblies, and methods of operating and fabricating such bearing assemblies and apparatuses are disclosed. In an embodiment, the plurality of PCD bearing elements of one or more of the bearing assemblies disclosed herein include at least one first PCD bearing element. At least a portion of the first PCD bearing element exhibits a coercivity of about 125 Oersteds or more and a specific magnetic saturation of about 14 Gauss.Math.cm.sup.3/gram or less. The first PCD bearing element includes a bearing surface with at least one groove formed therein. In an embodiment, the plurality of PCD bearing elements also include at least one second PCD bearing element. The second PCD bearing element exhibits a coercivity that is less than and a specific magnetic saturation that is greater than the first PCD bearing element.

Bearing assemblies that include a plurality of polycrystalline diamond (“PCD”) bearing elements, bearing apparatuses including such bearing assemblies, and methods of operating and fabricating such bearing assemblies and apparatuses are disclosed. In an embodiment, the plurality of PCD bearing elements of one or more of the bearing assemblies disclosed herein include at least one first PCD bearing element. At least a portion of the first PCD bearing element exhibits a coercivity of about 125 Oersteds or more and a specific magnetic saturation of about 14 Gauss.Math.cm.sup.3/gram or less. The first PCD bearing element includes a bearing surface with at least one groove formed therein. In an embodiment, the plurality of PCD bearing elements also include at least one second PCD bearing element. The second PCD bearing element exhibits a coercivity that is less than and a specific magnetic saturation that is greater than the first PCD bearing element.

A shrouded screw apparatus includes an outer tube, a telescoping inner tube, an auger bit, and an anti-rotation pin. The outer tube has a first sidewall defining a first interior chamber. The first sidewall has an opening defined therethrough. The inner tube is positioned in the first interior chamber. The inner tube has a second sidewall defining a second interior chamber. The second sidewall has a longitudinal groove defined therein. The inner tube is configured to extend from and retract within the first interior chamber of the outer tube. The auger bit is positioned in the second interior chamber and is rotatably coupled to the inner tube. The anti-rotation pin is coupled to the first sidewall of the outer tube and extends inwardly into the first interior chamber. The pin engages the longitudinal groove of the inner tube.

A shrouded screw apparatus includes an outer tube, a telescoping inner tube, an auger bit, and an anti-rotation pin. The outer tube has a first sidewall defining a first interior chamber. The first sidewall has an opening defined therethrough. The inner tube is positioned in the first interior chamber. The inner tube has a second sidewall defining a second interior chamber. The second sidewall has a longitudinal groove defined therein. The inner tube is configured to extend from and retract within the first interior chamber of the outer tube. The auger bit is positioned in the second interior chamber and is rotatably coupled to the inner tube. The anti-rotation pin is coupled to the first sidewall of the outer tube and extends inwardly into the first interior chamber. The pin engages the longitudinal groove of the inner tube.

Bearing assemblies, apparatuses, systems, and methods include bearing assemblies where one of the bearing assemblies may include bearing surfaces defining an at least partially conical surface.

Bearing assemblies, apparatuses, systems, and methods include bearing assemblies where one of the bearing assemblies may include bearing surfaces defining an at least partially conical surface.

An isolated lubrication system for a drill bit is disclosed. The system comprises a body having a cutting arm with a journal and a rotary cutter mounted on the journal. The system also comprises a reservoir in a body to contain a fluid lubricant that isolated from communication outside the body. The system also comprises multiple conduits in communication with the reservoir and with respect to each other. The multiple conduits facilitate lubrication between the journal and the rotary cutter, including the bearings, by means of a gravitational force and/or a centrifugal force acting of the fluid lubricant. Further, the system comprises a sealing system. The sealing system includes a sealing cap provided to the reservoir, a seal provided between the journal and the rotary cutter, and a stepped passageway provided in a clearance between the rotary cutter and a cutting arm of the body.

A hole opener includes a body with cone arms. The body includes pockets formed in the body in which each of the pockets includes a forwardly-positioned shoulder pocket section, a rearwardly-positioned tapered pocket section and a base opening axially extending through a wall of the corresponding pocket that receives a fastener therethrough. The cone arms each include a cone head attached to an arm. The arm includes a forwardly-positioned shoulder arm section, a rearwardly-positioned tapered arm section, and a rearwardly-facing opening axially extending through the rearwardly-positioned tapered arm section that receives the fastener. When each of the cone arms is inserted into a corresponding one of the pockets and the corresponding fastener(s) is/are tightened, the rearwardly-positioned tapered arm section is securely drawn into the rearwardly-positioned tapered pocket section of the pocket to create a pre-loaded fit therebetween and the forwardly-positioned shoulder arm section mates with the forwardly-positioned shoulder pocket section.