An apparatus is provided that includes a diamond bearing surface positioned in sliding engagement with an opposing bearing surface of a diamond reactive material. The opposing bearing surface is hardened via a material treatment.

A roller hydraulic valve lifter includes a body having a longitudinal central axis and an interior area defined by an inside surface which has a pair of flat surfaces opposite one another and connected by a pair of walls. A first bore, essentially perpendicular to the longitudinal axis, extends through the flat surfaces. A bearing is disposed partially in the interior area. The bearing includes an outer ring having substantially cylindrical exterior and interior bearing surfaces. A shaft extends through the first bore and the outer ring and between the pair of flat surfaces. A plurality of needle rollers is disposed between and rollingly engage the shaft and the cylindrical inner bearing surface. The shaft and the plurality of needle rollers are manufactured from an AISI 52100 alloy steel that is carbo-nitrided. The shaft and the plurality of needle rollers have a surface hardness of a minimum of HRc 65.

A turbocharger shaft includes a connection portion at a connection with a wheel of the turbocharger. The shaft includes a stainless steel cladding at least along one or more grooves of the connection portion to reduce the risk of cold cracking and bending fatigue.

A sealing arrangement having a rod seal for sealing a cavity for a flowable medium in the region of a rod includes an output apparatus for discharging the flowable medium. The rod is movably supported in a housing to be displaced in an axial direction. The housing has a bearing portion, wherein the rod seal is supported in a fixed manner and wherein the rod extends through the bearing portion and the rod seal so that a first rod portion and a second rod portion are arranged at different sides of the bearing portion. The first rod portion is located at a side facing the cavity and the second rod portion is located at a side facing away from the cavity. The rod seal is arranged at the side of the bearing portion facing the first rod portion and has a first sealing lip and a second sealing lip that are spaced apart from each other in the axial direction and circumferentially contact the rod. The bearing portion facing the cavity has a discharge structure having a support face which circumferentially surrounds the rod. The rod seal is in abutment with the support face and the support face has a diameter which increases in the direction of the second rod portion.

A wear-resistant copper-zinc alloy includes in mass %, 28 to 55% Zn, 0.5 to 2% P, and a balance of Cu and unavoidable impurities, and the wear-resistant copper-zinc alloy has an electrical conductivity of 10 to 33% IACS and a hardness of 3.6[Zn]-55 HBW or more, where [Zn] denotes the Zn content in mass %. Alternatively, a wear-resistant copper-zinc alloy includes in mass %, 40 to 55% Zn, 1 to 6% Mn, and a balance of Cu and unavoidable impurities, and the wear-resistant copper-zinc alloy has an electrical conductivity of 10 to 33% IACS and a hardness of 3.6[Zn]-55 HBW or more, where [Zn] denotes the Zn content in mass %.

A fluid machine includes a rotating body, an operation body rotated integrally with the rotating body, a housing, hydrodynamic plain bearings rotatably supporting the rotating body relative to the housing, and a cooling passage arranged in the housing. The hydrodynamic plain bearings each include a resin coating layer at a portion that is opposed to the rotating body. The hydrodynamic plain bearings include at least one combination of hydrodynamic plain bearings. Each combination includes an upstream hydrodynamic plain bearing and a downstream hydrodynamic plain bearing located at different positions in a direction in which the fluid flows through the cooling passage. The coating layer of the upstream hydrodynamic plain bearing has a lower hardness than the coating layer of the downstream hydrodynamic plain bearing.

A bearing unit having a stationary radially outer ring, a radially inner ring rotatable about a central rotation axis (X) of the bearing unit is provided with at least one raceway and, in an end portion thereof, with at least two circular sector segments, at least one row of rolling elements interposed between the radially outer ring and the radially inner ring, and a concentric collar for clamping the radially inner ring on a rotating shaft, where an induction-hardening heat treatment is applied to a portion of the radially inner ring that overlaps with at least a portion of the at least one raceway.

An example bushing of a hydraulic hammer tool includes an outer region and an inner region. The inner region has a relatively greater hardness than the outer region. The inner region may also be compressively stressed, while the outer region may have tensile stress. The stress and/or hardness profile of the bushing may enhance its resistance to wear and galling defects when a hammer of the hydraulic hammer tool is held in alignment by the bushing. The outer region of the bushing may be relatively soft, resulting in the bushing having a relatively high level of toughness. The bushing may be formed using medium to high carbon steel by rough forming the bushing, hardening the bushing, tempering the bushing, and induction softening the outer region of the bushing.

A method of forming a bearing cage is generally disclosed herein. The method includes (i) forming a bearing cage from either titanium or a titanium alloy; and (ii) applying a plasma-nitriding treatment to at least one surface of the bearing cage to form a compound layer of titanium nitride including TiN and Ti.sub.2N on an outer region of the at least one surface. Step (ii) further forms a diffusion zone adjacent to the outer region, in one aspect. A surface hardness of the bearing cage that is treated by the plasma-nitriding step is at least 1000 HV. The bearing cage is configured to be used in a turbofan, turboprop, or turboshaft engine or in a helicopter gearbox, in one aspect.

A bearing includes a ring unit including an outer ring and an inner ring. The inner ring is surrounded by the outer ring and shares a common axis. The outer ring includes at least one first recess, and the inner ring includes at least one second recess. Each of the at least one first recess and the at least one second recess is filled with a first durable material elements by way of welding. At least one roller unit including multiple rollers which rolls between the inner and outer rings. The rollers contact the multiple first durable material elements. The hardness of the multiple first durable material elements and the hardness of the rollers are higher than that of the ring unit so as to increase the life of use of the bearing and reduce manufacturing cost.