An electric submersible pump assembly with integral heat exchanger, high-speed self-aligning bearings, and dual bearing thrust chamber is described. The described pump assembly, modules, and components may be used for operating an electric submersible pump at high speeds as well as over a wide range of speeds and flowrates without replacing downhole equipment. The described pump assembly may be shorter than comparable pump assemblies and may be assembled offsite, thereby leading to faster and easier installation with less down time. By operating over a wide range of speeds, the disclosed pump assembly allows the operator to reduce overall inventory, reduce down time for the well, and avoid other complications associated with replacing a pump assembly or other downhole components.

A bearing bushing for a charging device may include an inner jacket surface including at least two radial depressions. A respective lowest point of the at least two radial depressions may be disposed on a circle having a radius R1. A plurality of plateau surfaces may be disposed circumferentially between the at least two radial depressions and may be offset radially towards an inside of the bearing bushing. The plateau surfaces may be curved and may have a constant radius R2. A ratio between the radius R1 and the radius R2 may correspond to the relationship: R1/R2=1.001 to 1.015.

A bearing structure includes a plurality of wave-shaped grooves and an inner surface. The wave-shaped grooves are formed on the inner surface for receiving a lubricating fluid. Each of the wave-shaped grooves extends along a longitudinal axis of the bearing structure. Each of the wave-shaped grooves includes a first peak section, a second peak section, two first connecting sections, two second connecting sections and a trough section. The two first connecting sections are connected to opposite sides of the first peak section, and the two second connecting sections are connected to opposite sides of the second peak section. The trough section is disposed between the first peak section and the second peak section, and the trough section is connected to one of the first connecting sections and one of the second connecting sections. The first and second peak sections and the trough section have a circular arc structure.

On an inner peripheral surface of a bearing hole into which a shaft is inserted, concave oil supply surfaces arranged dispersively like separated islands and a sliding surface continuous around the oil supply surfaces to hold an outer peripheral surface of the shaft are formed: a maximum height difference between the sliding surface and the oil supply surfaces is not less than 0.01% and not more than 0.5% of an inner diameter Di of the sliding surface; a surface aperture area ratio of pores at the sliding surface is not more than 10%; a surface aperture area ratio of pores at the oil supply surfaces is more than 10% and less than 40%; and an area of each of the oil supply surfaces is not less than 0.03 mm.sup.2 and not more than 0.2Di.sup.2 (mm.sup.2).

A mechanical assembly including a shaft, a mechanical device providing, a bearing mounted on the shaft and including at least one ring that is able to move in rotation about the shaft, a lubrication system having a channel to allow lubricant fluid to flow, formed at the interface between the shaft and the bearing, distribution ducts for lubricant fluid, formed in the bearing and fluidically connected to the channel. The channel provides at least one constriction to create a loss of head of the lubricant fluid flowing in the channel.

A liquid metal or spiral groove bearing structure for an x-ray tube and associated process for manufacturing the bearing structure is provided in which journal bearing sleeve is formed with a number of structures thereon that function to dissipate heat transmitted to the sleeve during operation of the bearing assembly within the x-ray tube to minimize thermal deformation of the sleeve, thereby minimizing gap size alteration within the bearing assembly. The structures formed within the sleeve are slots disposed within the section of the sleeve in which the highest temperature gradients develop. The slots enable an increase in thermal conductance away from the sleeve while minimizing the stresses created from the deformation of the portion(s) of the sleeve between the slots.

A liquid metal or spiral groove bearing structure for an x-ray tube and associated process for manufacturing the bearing structure is provided in which journal bearing sleeve is formed with a number of structures thereon that function to dissipate heat transmitted to the sleeve during operation of the bearing assembly within the x-ray tube to minimize thermal deformation of the sleeve, thereby minimizing gap size alteration within the bearing assembly. The structures formed within the sleeve are slots disposed within the section of the sleeve in which the highest temperature gradients develop. The slots enable an increase in thermal conductance away from the sleeve while minimizing the stresses created from the deformation of the portion(s) of the sleeve between the slots.

Provided is a slide bearing capable of sustaining sliding performance over long period.

A slide bearing has an upper case (2) configured to be attached to an upper support for attachment of a suspension to a vehicle body, a lower case (3) rotatably combined with the upper case (2) to form an annular space (7); and an annular center plate (4) and an annular sliding sheet (5) both placed within the annular space (7). The center plate (4) includes a bearing surface (40) slidable with the sliding sheet (5) and an annular groove (42) formed on the bearing surface (40) so as to hold lubricant. The annular groove (42) has an inner circumferential surface (43a) inclining down from the opening section toward the groove bottom section as it goes outwardly in the radial direction and an outer circumferential surface (43b) inclining down from the opening section toward the groove bottom section as it goes inwardly in the radial direction. A line P of intersection between the inner circumferential surface (43a) and the outer circumferential surface (43b) is located closer to the bearing surface (40) than to a back face (41) of the center plate (4).

A piston for an internal combustion engine may include two pin bosses configured to receive a gudgeon pin. The two pin bosses may respectively include a nadir pocket of at least two nadir pockets at =180 and extending outward from a piston axis. The at least two nadir pockets may have a respective length that is smaller than a length of a respective pin boss of the at least two pin bosses. The piston may also include a pin boss axis that is axially offset from the piston axis by 0.1-1.0 mm.

A thrust washer includes an annular body with an aperture therein and having a first axial face and a second axial face, an outer diameter edge and an inner diameter edge extending between the first and second axial faces. At least one of the first and second axial faces includes a plurality of recessed grooves extending at least partially between the inner edge and the outer edge and defining un-recessed lands between the recessed grooves. The plurality of recessed grooves include a transition region transitioning to the lands and a scoop region separated from the transition region by a stepped wall portion extending between the scoop region and the tapered region. The recessed grooves can include directional symmetric bi-directional grooves for use in systems with rotation in both directions.