Bearing assemblies, such as angular contact bearing assemblies, and methods of producing the same are disclosed. One angular contact ball bearing may include an inner ring and an outer ring, the inner ring having an outer raceway and the outer ring having an inner raceway. A plurality rolling elements may be arranged between the outer raceway and the inner raceway. The outer raceway may be formed by an extrusion of the inner ring and/or the inner raceway may be formed by an extrusion of the outer ring. The raceways may be extruded in their final contour, without any cutting.

A rolling machine has a rolling die 4 that forms a male screw by pressing a steering shaft 14 which is an object to be rolled and plastically deforming an outer peripheral surface of the steering shaft 14 while rotating in contact with the outer peripheral surface of the steering shaft 14, a main spindle 3 inserted into a penetration hole 10 of the rolling die 4 and transmitting a rotation force to the rolling die 4, a key groove and a key which restrict a relative rotation between the rolling die 4 and the main spindle 3, a spiral oil groove 16 provided on an inner peripheral surface of the penetration hole 10 or an outer peripheral surface of the main spindle and extending from one end portion 10b side in an axial direction of the penetration hole in an inner axial direction of the penetration hole.

A rolling machine has a rolling die 4 that forms a male screw by pressing a steering shaft 14 which is an object to be rolled and plastically deforming an outer peripheral surface of the steering shaft 14 while rotating in contact with the outer peripheral surface of the steering shaft 14, a main spindle 3 inserted into a penetration hole 10 of the rolling die 4 and transmitting a rotation force to the rolling die 4, a key groove and a key which restrict a relative rotation between the rolling die 4 and the main spindle 3, a spiral oil groove 16 provided on an inner peripheral surface of the penetration hole 10 or an outer peripheral surface of the main spindle and extending from one end portion 10b side in an axial direction of the penetration hole in an inner axial direction of the penetration hole.

There is provided a method for manufacturing ring-shaped members at a good yield and high production efficiency. To achieve this object, the following is performed. A single (a sequence of) forging produces a joined body formed by radially coupling four cylindrical portions with different inner diameter sizes. A cylindrical member that has the largest inner diameter size and a cylindrical member that has the third largest inner diameter size after the forging are employed as ring-shaped members without change. A rolling process is performed on respective cylindrical member that has the smallest inner diameter size and cylindrical member that has the second largest inner diameter size to obtain ring-shaped members. Thus, two sets of ring-shaped members are obtained as two sets of inner rings and outer rings.

There is provided a method for manufacturing ring-shaped members at a good yield and high production efficiency. To achieve this object, the following is performed. A single (a sequence of) forging produces a joined body formed by radially coupling four cylindrical portions with different inner diameter sizes. A cylindrical member that has the largest inner diameter size and a cylindrical member that has the third largest inner diameter size after the forging are employed as ring-shaped members without change. A rolling process is performed on respective cylindrical member that has the smallest inner diameter size and cylindrical member that has the second largest inner diameter size to obtain ring-shaped members. Thus, two sets of ring-shaped members are obtained as two sets of inner rings and outer rings.

A method is for treating at least one part of a metal component that is at least partly produced by additive manufacturing. The method comprises the steps of heating the at least one part of the metal component to form at least one softened region, and applying a mechanical load to the at least one softened region to plastically deform the metal in the at least one softened region.

A method of manufacturing a cylindrical ring member includes a step of forming a metal intermediate material having a cylindrical portion and a chamfering step by cold forging in which a normal chamfer portion is formed on an axial end peripheral edge of the cylindrical portion by pressing a radial end portion of an axial end surface of the cylindrical portion against an annular chamfering surface provided in a mold configuring a mold device. A chamfering step is performed by cold forging in a state where a preliminary chamfer portion, of which a width dimension in a radial direction is larger than a width dimension of the normal chamfer portion in a radial direction, is formed on the axial end peripheral edge of the cylindrical portion.

A method of manufacturing a cylindrical ring member includes a step of forming a metal intermediate material having a cylindrical portion and a chamfering step by cold forging in which a normal chamfer portion is formed on an axial end peripheral edge of the cylindrical portion by pressing a radial end portion of an axial end surface of the cylindrical portion against an annular chamfering surface provided in a mold configuring a mold device. A chamfering step is performed by cold forging in a state where a preliminary chamfer portion, of which a width dimension in a radial direction is larger than a width dimension of the normal chamfer portion in a radial direction, is formed on the axial end peripheral edge of the cylindrical portion.

Bearing assemblies, such as angular contact bearing assemblies, and methods of producing the same are disclosed. One angular contact ball bearing may include an inner ring and an outer ring, the inner ring having an outer raceway and the outer ring having an inner raceway. A plurality rolling elements may be arranged between the outer raceway and the inner raceway. The outer raceway may be formed by an extrusion of the inner ring and/or the inner raceway may be formed by an extrusion of the outer ring. The raceways may be extruded in their final contour, without any cutting.

A roughly shaped material for a rolling bearing of the present invention is produced by forging a steel composed of a high-carbon chrome bearing steel containing 0.7 mass % to 1.2 mass % of a carbon, and 0.8 mass % to 1.8 mass % of a chromium to a predetermined shape while heating the steel to a forging temperature in a range of (Ae.sub.1 point+25 C.) to (Ae.sub.1 point+105 C.), cooling a forged article to a temperature of Ae.sub.1 point or lower, and performing an annealing in which the forged article that is obtained is heated to a soaking temperature in a range of (Ae.sub.1 point+25 C.) to (Ae.sub.1 point+85 C.), the forged article is retained for 0.5 hours or longer, and the forged article is cooled down to 700 C. or lower at a cooling rate of 0.30 C./s or slower.