A ring rolling device includes a drive roller and a rotatable revolving drum, in which five mandrels are rotatably mounted. Ring blanks can be mounted around the mandrels. By rotating the revolver drum, the mandrels move towards and away from the drive roller. The revolver drum is arranged in relation to the drive roller such that by rotating the revolver drum a decreasing roll gap is formed between a mandrel approaching the drive roller and the drive roller, in which roll gap a ring blank mounted around the mandrel is rolled during the rotating of the revolver drum. The revolver drum has four rotatably mounted support rollers, said support rollers supporting the mandrel in the direction of the rotational axis of the revolving drum, such that, during the rolling process, the mandrel is located between the support rollers and the press element.

In a ring-rolling machine having a mandrel roll and a related radial roll, the mandrel roll can be handled in operationally reliable and structurally simple manner if an axial bearing of the mandrel roll is opened by way of an opening drive that does not rotate along with the mandrel roll and/or is closed by inserting the mandrel roll into the axial bearing.

In a ring-rolling machine having a mandrel roll and a related radial roll, the mandrel roll can be handled in operationally reliable and structurally simple manner if an axial bearing of the mandrel roll is opened by way of an opening drive that does not rotate along with the mandrel roll and/or is closed by inserting the mandrel roll into the axial bearing.

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 near-net shape forming method for fabricating the precise bearing ring forging is invented. The processing method is composed of following three procedures. (1) the precise ring-like billet with chamfer angle is manufactured by the machining method. (2) The billet is heated by the less oxidation or non-oxidation heating method before ring rolling. (3) The bearing ring forging integrating with the raceway is formed in one pass of the rolling process by the ring rolling method.

A rotor bearing having a rolling bearing raceway in an unhardened core region of a rolling bearing ring element that further includes an outer layer hardened to a surface hardening depth wherein the rolling bearing raceway is formed by a roll, wherein a diameter of the roll is 8 to 25 times the surface hardening depth.

A rotor bearing having a rolling bearing raceway in an unhardened core region of a rolling bearing ring element that further includes an outer layer hardened to a surface hardening depth wherein the rolling bearing raceway is formed by a roll, wherein a diameter of the roll is 8 to 25 times the surface hardening depth.

A method for producing a composite rolling bearing (1) having a bearing flange (3) and at least one rolling bearing (4, 5) held on the bearing flange (3) by an inner ring (6, 7). In order to be able to fix the inner ring (7) on the bearing flange (3) with axial preloading without expansion, the inner ring (7) is acted upon by a holding-down device (23) that radially holds down the inner ring (7) and is preloaded against the inner ring (7) by a regulated axial force (F), and, by way of an advancing cone (21) introduced radially on the inside axially into the bearing flange (3), material (11) present on the bearing flange (3) is displaced radially towards the outside into a recessed formation (15, 16) in the inner ring (7).

A method for producing a composite rolling bearing (1) having a bearing flange (3) and at least one rolling bearing (4, 5) held on the bearing flange (3) by an inner ring (6, 7). In order to be able to fix the inner ring (7) on the bearing flange (3) with axial preloading without expansion, the inner ring (7) is acted upon by a holding-down device (23) that radially holds down the inner ring (7) and is preloaded against the inner ring (7) by a regulated axial force (F), and, by way of an advancing cone (21) introduced radially on the inside axially into the bearing flange (3), material (11) present on the bearing flange (3) is displaced radially towards the outside into a recessed formation (15, 16) in the inner ring (7).