A spherical bearing having an outer ring and an inner ring respectively including an inner surface and an outer surface that are in contact with one another. Moreover, the material of the outer ring provides an alloy having the formula NiCr19Fe18Nb or an alloy having the formula X6NiCrTiMoVB25-15-2.

To provide a method of manufacturing a shaft for a steering device, the shaft including a spline shaft part to be coupled with an input shaft, a stopper part to be coupled with an output shaft, and an intermediate shaft part that couples the spline shaft part with the stopper part. The method includes: a step of forming a hole part recessed in an axial direction from one end of a pillar-shaped material by forging; and a step of pressing the material in which the hole part has been formed into a die to perform drawing in a radial direction on a portion of the material at which the spline shaft part and the intermediate shaft part are formed, and prolonging a length along the axial direction of the hole part at the same time by forging.

An example bushing of a hydraulic hammer tool includes a bulk region and an inner region. The inner region has a relatively greater hardness than the bulk region. The inner region may also be compressively stressed, while the bulk 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 bulk 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, induction hardening the inner region of the bushing, and then quenching the inner region.

A forged outer ring of a tapered wheel bearing incudes a conical ring section having a first end and a second end, a flange section and a central ring section having a first end at the flange section and a second end at the conical ring section. An inner surface of the conical ring section is configured to form a raceway for a first set of tapered rollers. An inner diameter of the first end of the conical ring section is smaller than an inner diameter of the second end of the central ring section and a wall thickness of the second end of the conical ring section is greater than a wall thickness of the first end of the conical ring section.

Radially outer ring of a bearing unit for a hub-wheel assembly for motor vehicles, the radially outer ring being provided with: a flange portion having a plurality of axial fixing holes that connect an element of the motor vehicle wheel to the radially outer ring, an almost cylindrical portion which with part of its radially internal surfaces defines raceways for rows of rolling bodies of the bearing unit, an axially internal or axially external surface of the flange portion and a radially external surface of the cylindrical portion connected to each other by a first portion of toroidal surface (St1) and of a second portion of toroidal surface (St2) defined by corresponding first radius (R1) and second radius (R2), a truncated cone surface (Stc) defined by an angle (a) formed with a rotation axis (X) of the radially outer ring is interposed between the first portion of toroidal surface (St1) and the second portion of toroidal surface (St2).

The present invention provides a steel material which is excellent in both of the strength (particularly, fatigue strength) and the manufacturability (particularly, bending straightening properties), and thus can be used as an automobile component such as a crankshaft by being formed into a product shape, being subjected to a high strength treatment such as a nitrocarburizing treatment, and then being subjected to the bending straightening.

A forged crankshaft (1) includes a carbon steel containing S, wherein in a portion corresponding to a machined outer circumferential surface of a shaft part such as journals (J), crank pins (P), a front part (Fr), and a flange (Fl), a ratio x/y of an area rate x of sulfide in a position (X) corresponding to a parting surface of a die for finish forging to an area rate y of sulfide in a position (Y) corresponding to a bottom of a die impression of the die for finish forging is equal to or lower than 1.5. The forged crankshaft (1) can avoid an occurrence of machined surface cracks on the journals (J) and the crank pins (P) after the outer circumferential surface is machined.

A valve device includes a body that defines a passage through which a fluid flows, a shaft that is movably supported with respect to the body and defines an axis, a valve element that is fixed to the shaft to open and close the passage; and a cylindrical bearing bush that movably supports the shaft with respect to the body, in which the bearing bush includes a mixed region in which a metal core material and expanded graphite are mixed with each other, and a first expanded graphite region made of only the expanded graphite such that the metal core material is not exposed in an inner circumferential side region in contact with an outer circumferential surface of the shaft.

Radially outer ring of a bearing unit for a hub-wheel assembly for motor vehicles, the radially outer ring being provided with: a flange portion having a plurality of axial fixing holes that connect an element of the motor vehicle wheel to the radially outer ring, an almost cylindrical portion which with part of its radially internal surfaces defines raceways for rows of rolling bodies of the bearing unit, an axially internal or axially external surface of the flange portion and a radially external surface of the cylindrical portion connected to each other by a first portion of toroidal surface (St1) and of a second portion of toroidal surface (St2) defined by corresponding first radius (R1) and second radius (R2), a truncated cone surface (Stc) defined by an angle (a) formed with a rotation axis (X) of the radially outer ring is interposed between the first portion of toroidal surface (St1) and the second portion of toroidal surface (St2).

The invention relates to the technical field of microstructure refinement and homogenization of bearing steel, and specifically relates to a high-carbon bearing steel and a method of preparing same. The high-carbon bearing steel of the invention has the following chemical composition: C: 0.80˜1.20 wt %, Cr: 0.40˜2.0 wt %, Mn: 0.15˜0.75 wt %, Si: 0.15˜0.75 wt %, Nb: 0˜0.20 wt %, Mo: 0˜0.20 wt %, V: 0˜0.20 wt %, P≤0.015 wt %, S≤0.01 wt %, the remaining is Fe and unavoidable impurities; the contents of Nb, Mo and V are not 0 at the same time. According to the invention, microalloying elements such as Nb, Mo and V, in combination with other elements, are added into the high-carbon bearing steel to effectively refine the bearing steel matrix and promote the precipitation of a large amount of nano-carbides, thereby enhancing the contact fatigue life of the high-carbon bearing steel.