A mud-lubricated bearing section including a seal assembly for directing a fluid flowing through a mud-lubricated bearing into a central bore of a mandrel. At least one mud-lubricated bearing is positioned in an annular space between the mandrel and a housing. The seal assembly directs the fluid from the annular space through a mandrel fluid port into the mandrel central bore. The seal assembly seals the annular space, and includes a piston, a plug, and a chamber between the piston and the plug. The piston is configured for axial movement relative to the mandrel and the housing, while the plug is axially fixed relative to the mandrel and/or the housing. The chamber is configured to contain a lubricating fluid. The piston includes inner and outer seals. The plug includes a lower seal and a passage allowing the fluid from the chamber to reach the lower seal for lubrication.

The various technologies presented herein relate to fabrication and operation of a heat exchanger that is configured to extract heat from an underlying substrate. Heat can be extracted by way of an air gap formed between an impeller and a baseplate. By utilizing a pump to create an initial air gap that is further maintained by rotation of the impeller relative to the baseplate, a spring can be utilized that can apply a force of greater magnitude to the impeller than is used in a conventional approach, thus enabling the weight of the impeller to be negligible with respect to a width of the air gap, thereby conferring the desirable feature of orientation independence with respect to gravity with no performance degradation.

The various technologies presented herein relate to fabrication and operation of a heat exchanger that is configured to extract heat from an underlying substrate. Heat can be extracted by way of an air gap formed between an impeller and a baseplate. By utilizing a pump to create an initial air gap that is further maintained by rotation of the impeller relative to the baseplate, a spring can be utilized that can apply a force of greater magnitude to the impeller than is used in a conventional approach, thus enabling the weight of the impeller to be negligible with respect to a width of the air gap, thereby conferring the desirable feature of orientation independence with respect to gravity with no performance degradation.

A universal joint includes a bush, a bearing journal supported in the bush by a bearing and a seal assembly configured to form a seal between the bearing journal and the bush. The seal assembly includes an outer body formed from a first material having a first hardness, and a reinforcing body at least partially embedded in the outer body is formed from a second material having a hardness greater than the hardness of the first material. The reinforcing body contacts and forms a slip surface for a rolling element of the bearing. The reinforcing body and the outer body are configured such that the reinforcing body compresses a portion of the outer body against the journal when the seal assembly is mounted on the bearing journal.

A rotation mechanism includes: a housing; a shaft inserted through a hole provided at the housing; bearings installed at the housing and rotatably supporting the shaft; a rotary member provided at one end portion of the shaft, adapted to be rotated together with the shaft, and having a portion that projects to a radially outer side of the hole and faces the housing with a gap having a predetermined size; and a gas passage adapted to connect the gap to outside of the housing and allow gas contained in a portion of the gap to pass to the outside of the housing.

A rotation mechanism includes: a housing; a shaft inserted through a hole provided at the housing; bearings installed at the housing and rotatably supporting the shaft; a rotary member provided at one end portion of the shaft, adapted to be rotated together with the shaft, and having a portion that projects to a radially outer side of the hole and faces the housing with a gap having a predetermined size; and a gas passage adapted to connect the gap to outside of the housing and allow gas contained in a portion of the gap to pass to the outside of the housing.

A slew bearing includes a stationary bearing ring to be fixed to a base, a moveable bearing ring to be fixed to a moveable object, wherein the stationary bearing ring and the moveable bearing ring are configured to enable rotation of the moveable bearing ring relative to the stationary bearing ring about a rotation axis. A main axial bearing and an auxiliary bearing are provided between the stationary bearing ring and the moveable bearing ring, wherein the moveable bearing ring includes one or more main portions and one or more auxiliary portions, which one or more main portions are moveable relative to the one or more auxiliary portions between an operational position, in which the main axial bearing transfers the axial loads between moveable bearing ring and stationary bearing ring, and a maintenance position, in which the auxiliary axial bearing transfers the axial loads between moveable bearing ring and stationary bearing ring and the main bearing is allowed to be inspected and/or maintained so that the slew bearing during inspection and/or maintenance is still operational.

A slew bearing includes a stationary bearing ring to be fixed to a base, a moveable bearing ring to be fixed to a moveable object, wherein the stationary bearing ring and the moveable bearing ring are configured to enable rotation of the moveable bearing ring relative to the stationary bearing ring about a rotation axis. A main axial bearing and an auxiliary bearing are provided between the stationary bearing ring and the moveable bearing ring, wherein the moveable bearing ring includes one or more main portions and one or more auxiliary portions, which one or more main portions are moveable relative to the one or more auxiliary portions between an operational position, in which the main axial bearing transfers the axial loads between moveable bearing ring and stationary bearing ring, and a maintenance position, in which the auxiliary axial bearing transfers the axial loads between moveable bearing ring and stationary bearing ring and the main bearing is allowed to be inspected and/or maintained so that the slew bearing during inspection and/or maintenance is still operational.

A bearing assembly for a gas turbine engine comprises a bearing; a bearing bracket, which holds the bearing and is secured by a predetermined breaking device on a connecting element, which can be connected or is connected to a loadbearing structure of the gas turbine engine; a first toothed component mounted on the bearing bracket; and a second toothed component fixed on the connecting element, wherein, after the destruction of the predetermined breaking device, the first toothed component and the second toothed component can be or are brought into engagement with one another in such a way that one of the toothed components can be made to roll on the other. A gas turbine engine and a method are furthermore provided.

A bearing arrangement having: a first element having an inner race and a first bearing surface; a second element, pivotable relative to the first element about a first axis, and having an outer race and a second bearing surface that cooperates with the first bearing surface to form a plain bearing. The bearing arrangement also includes a roller element disposed between the inner and outer races to form a rolling bearing. The inner and outer races are arcuate and subtend an angle of less than 360 about the first axis.