A technique facilitates drilling applications by providing a unique flex joint. In one embodiment, the flex joint has an adjustable bending stiffness while being much more compact than conventional flex joints. The flex joint also may be designed to de-couple bending moments from the tool joints and, in some applications, can operate as an active vibration and shock control sub by incorporating suitable sensors and a hydraulic actuator system. The design also enables incorporation of other features, such as electrical insulation features disposed above and/or below the flex joint. In some applications, the flex joint also may have an electrical feed through.

Methods of screening a polycrystalline diamond element for suitability for electrical discharge machining (“EDM”). The method includes providing a PCD element including a plurality of bonded diamond grains, determining at least one characteristic of the PCD table correlated to electrical conductivity of the PCD element, and EDM the PCD element if the value of the at least one characteristic correlates to an electrical conductivity above a threshold value.

Superhard compacts, assemblies including the same, and methods of using the same are disclosed herein. An example assembly includes at least one superhard compact secured to a support body. The support body includes at least one exterior surface and defines at least one recess extending inwardly from the exterior surface. The recess is configured to receive at least a portion of the superhard compact. The assembly includes at least one magnet that secures the superhard compact to the support body. For example, the magnet may form part of the superhard compact, the support body, or both.

The invention relates to a bearing arrangement for a drilling head, through which flushing liquid flows, of a deep drilling device, having multiple radially outer and radially inner bearing rings, wherein the radially outer bearing rings are arranged coaxially over the radially inner bearing rings, wherein, radially between the bearing rings, there are arranged balls which roll in raceways of the bearing rings, and wherein the raceways are delimited axially on both sides by shoulders with mutually opposite shoulder surfaces which run parallel to a bearing longitudinal axis. In order for a bearing arrangement of this type, which, as per the prior art, is adjoined in an axial direction by at least one plain bearing, to be designed to be of short axial extent and in order to simplify the construction, the internal diameter (Di) of the shoulder surfaces of the radially outer bearing rings and the external diameter (Da) of the shoulder surfaces of the radially inner bearing rings are dimensioned such that said shoulder surfaces perform the function of parallel radial plain bearings with a radial clearance (S).

Embodiments of the invention relate to polycrystalline diamond (“PCD”) fabricated by sintering a mixture including diamond particles and a selected amount of graphite particles, polycrystalline diamond compacts (“PDCs”) having a PCD table comprising such PCD, and methods of fabricating such PCD and PDCs. In an embodiment, a method includes providing a mixture including graphite particles present in an amount of about 0.1 weight percent (“wt %”) to about 20 wt % and diamond particles. The method further includes subjecting the mixture to a high-pressure/high-temperature process sufficient to form PCD.

A device for supplying lubricant to a lubrication point in a machine, a tunnel boring machine, for example, includes a lubrication pump unit and a control unit. The lubrication pump unit is configured to supply a quantity of the lubricant to the lubrication point, and the control unit is configured to regulate the quantity of lubricant based on a sensor measurement signal. The sensor measurement signal may be based on a temperature measured in a region of the lubrication point, a pressure measured in a region of the lubrication point, a measured viscosity of the lubricant, a measured dielectricity of the lubricant, a measured water content of the lubricant, a vibration intensity measured at a part of the machine, or a measured rotational speed of a part of the machine.

A bearing system configured for use on a downhole tool including a rolling cutter member having a plurality of cutting structures thereon comprises a first plurality of bearings disposed between a head washer and an at least substantially planar shaft washer, and a second plurality of bearings disposed between the at least substantially planar shaft washer and a rolling cutter washer. A downhole tool, such as an earth-boring rotary rolling cutter drill bit includes such a bearing system between a rolling cutter and a head of a bit body. Methods of forming such a downhole tool include the assembly of such a bearing system between a rolling cutter and a head of a bit body.

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.

A rolling-element bearing assembly includes first and second bearing rings that form a bearing interior between them and a plurality of rolling elements disposed in the bearing interior and a seal assembly for sealing the bearing interior. The seal assembly includes a seal carrier and a seal element having at least one primary seal lip for sealing the bearing interior and a secondary seal lip for sealing against external contamination. The seal element is connected to the seal carrier such that the primary seal lip and the secondary seal lip abut axially against an axial end surface of the second bearing ring.

Bearing assemblies and bearing apparatuses are disclosed. In an embodiment, a first bearing assembly includes tilting pads and a first plurality of sliding superhard bearing elements secured to a first support ring. In an embodiment, a second bearing assembly includes a substantially continuous bearing element secured to a second support ring. In an embodiment, a bearing apparatus includes the first bearing assembly and the second bearing assembly, with the substantially continuous bearing element generally facing the tilting pads. At relatively low rotational speeds, the first plurality of superhard bearing elements supports at least a portion of a load exerted on the bearing assembly. At relatively high rotational speeds, the tilting pads support at least a majority of the load.