A tool includes a device including a housing and a rotor, the rotor to rotate about a longitudinal axis, and an axial gap generator including a stator assembly positioned adjacent to the rotor. The axial gap generator generates a voltage signal as a function of a gap spacing between the stator assembly and the rotor, the gap spacing being parallel to the longitudinal axis.

An improved sealed bearing pack for a downhole mud motor is disclosed. More specifically, embodiments of the present invention relate to a mud motor for straight and directional drilling with a sealed bearing pack designed to withstand higher torques, loads, and pressure operations and with a reduced failure rate. In some embodiments, the sealed bearing pack has more lateral support for improved horizontal drilling and extended operational life. Thus, one embodiment includes an adapter housing extending the length of the outer housing and a bearing within the adapter housing for increased support. Additionally, some embodiments include two thrust bearing assemblies for improved operations and reduced failures. Various embodiments include a longer flow sleeve than prior art sealed bearing packs.

Embodiments disclosed herein relate to bearing assemblies and methods of manufacturing. In an embodiment, a bearing assembly includes a support ring and bearing elements. The bearing elements are mounted to and distributed circumferentially about an axis of the support ring. At least one of the bearing elements includes a polycrystalline diamond table, a substrate bonded to the polycrystalline diamond table, bonding region defined by the substrate and the polycrystalline diamond table, and a corrosion resistant region. The corrosion resistant region includes a corrosion resistant material that covers at least a portion of at least one lateral surface of the bonding region. The corrosion resistant region prevents corrosion of at least some material in the bonding region covered by the corrosion resistant region (e.g., during use). Other embodiments employ one or more sacrificial anodes as an alternative to or in combination with the corrosion resistant region.

A slewing bearing providing a first ring, a second ring, the rings being concentric around a central axis (X1), at least one row of rolling elements arranged between the rings in order to form an axial thrust that can transmit axial forces, at least one row of rolling elements arranged between the rings in order to form a radial thrust that can transmit radial forces, and at least one sealing assembly arranged between the first ring and the second ring. The sealing assembly provides first sealing means being arranged outside second sealing means, an annular sealed chamber being defined between the first sealing means and second sealing means.

The invention relates to a drill drive for a drilling rig with a motor, by which a drive shaft is rotationally driven which is supported in a rotatable manner in a housing with a bearing arrangement having at least a radial bearing, a first axial bearing and a second axial bearing, wherein on the first axial bearing a first force measuring device is arranged for determining a first axial force on the first axial bearing and on the second axial bearing a second force measuring device is arranged for determining a second axial force on the second axial bearing.

Furthermore, the invention relates to a drilling rig, in particular for oil or gas drilling, with a drill mast, along which a drill string with a drilling tool is arranged, wherein on the drill mast a drill drive according to the invention is supported in a displaceable manner for rotationally driving the drill string.

A downhole-type device includes an electric machine. The electric machine includes an electrical rotor configured to couple with a device to drive or be driven by the electric machine. An electrical stator surrounds the electric rotor. The electric stator includes a seal configured to isolate stator windings from an outside, downhole environment. An inner surface of the seal and an outer surface of the electric rotor define an annulus exposed to the outside environment. A bearing couples the electric rotor to the electric stator. A lubrication system is fluidically coupled to the downhole-type device. The lubrication system includes a topside pressure pump and a downhole-type distribution manifold configured to be used within a wellbore. The distribution manifold is fluidically connected to the topside pressure pump and the bearing to receive a flow of lubricant from the topside pressure pump.

Among other things, a bearing assembly comprising a hybrid coating is provided. A bearing assembly may comprise a substrate having a surface and a hybrid wear resistant coating over the surface of the substrate. In an example, the substrate may be an inner radial bearing and/or and outer radial bearing within a bearing assembly. The hybrid wear resistant coating may comprise a high wear resistant coating and a low wear resistant coating. The high wear resistant coating may comprise a wear resistant matrix over the surface and a set of wear resistant elements within the wear resistant matrix. In an example, wear elements within the set of wear elements may comprise tungsten carbide. The low wear resistant coating may be over a low wear area of the surface. In an example, the low wear resistant coating may be positioned between the first high wear resistant coating and a second high wear resistant coating.

A bearing element for a bearing assembly has a body of polycrystalline diamond (PCD) material having a bearing contact surface, and a substrate bonded to the body of PCD material along an interface and having a free end surface. The substrate has a through-bore extending longitudinally therethrough, the body of PCD material having a portion extending through the through-bore in the substrate to at least the free end surface thereof, the substrate extending around the peripheral side edge of the portion of PCD material extending therethrough.

Methods for manufacturing bearings and wear resistant surfaces usable in various downhole tools are described herein. A housing is provided. A laser configured for insertion into the housing, such as an inner diameter laser, is used to connect a fusible material to the inner surface of the housing or an insert disposed therein to form a hard facing layer on the inner surface. Simultaneously or independently, the laser can be used to connect the fusible material to the outer surface of a mandrel within the housing to form a second hard facing layer. The present methods thereby produce durable radial bearings having extended operational life, which can be produced within a bearing housing, or externally for transport and installation in existing bearing housings.