Abstract: A method for induction surface hardening includes, when in a feed mode, moving an induction coil of a hardening device over a ring surface of a work piece in a treatment direction, to heat the ring surface from an initial zone to a final zone. A sprayer, located downstream of the induction coil in the direction of treatment, is activated to apply quenching liquid to the heated ring surface to both cool and harden the ring surface. An unhardened soft zone is provided between the initial zone and the final zone. A supplementary induction coil, the induction coil and the sprinkler are respectively activated and deactivated separately at the start and end of the hardening, while the relative feed speed between the hardening device and the work piece, and/or the power supplied to each of the supplementary induction coil and the induction coil, are varied at the same time.

Abstract: The invention relates to a method for the progressive induction surface hardening of a closed curve trace of a workpiece, the closed curve trace and a hardening device being moved relative to one another in a feed mode to harden the closed curve trace starting from an initial zone to an end zone, an unhardened soft zone being provided. According to the invention, the workpiece is provided with a marking, the hardening device having a sensor for detecting said marking. The curve trace and the hardening device are moved relative to one another along the treatment direction until the senor detects the marking. Once the marking is detected, another movement takes place in the treatment direction before the hardening device is activated, the curve trace being hardened by the relative movement. The marking is again detected by means of the sensor and the hardening device is then deactivated. The invention also relates to an arrangement which is suitable for carrying out the method described.

Abstract: Methods for induction surface hardening of a ring surface of a work piece. The ring surface and a hardening device have an induction coil moved relative to one another in a treatment direction in a feed mode. A sprinkler located downstream of the induction coil in the direction of treatment serves to heat the ring surface, starting from an initial zone to a final zone, with the induction coil and then hardens it by cooling the ring surface with the sprinkler. An unhardened soft zone is provided between the initial zone and the end zone. The supplementary induction coil, the induction coil and the sprinkler are activated and deactivated separately at the start of hardening and at the end of hardening, respectively, the speed between the hardening device and the work piece and/or the power supplied to the supplementary induction coil and the induction coil varied at the same time.

Abstract: The invention relates to a method for the induction surface hardening of a ring surface of a workpiece, the ring surface and a hardening device having an induction coil being moved relative to one another in a treatment direction in a feed mode. A sprinkler is located downstream of the induction coil when seen in the direction of treatment and serves to heat the ring surface, starting from an initial zone to a final zone, by means of the induction coil and then to harden it by cooling the ring surface by means of the sprinkler, an unhardened soft zone being provided between the initial zone and the end zone.

Abstract: The invention relates to a method for the induction surface hardening of a ring surface of a workpiece, the ring surface and a hardening device having an induction coil being moved relative to one another in a treatment direction in a feed mode. A sprinkler is located downstream of the induction coil when seen in the direction of treatment and serves to heat the ring surface, starting from an initial zone to a final zone, by means of the induction coil and then to harden it by cooling the ring surface by means of the sprinkler, an unhardened soft zone being provided between the initial zone and the end zone.

Abstract: The invention relates to a method for the progressive induction surface hardening of a closed curve trace of a workpiece, the closed curve trace and a hardening device being moved relative to one another in a feed mode to harden the closed curve trace starting from an initial zone to an end zone, an unhardened soft zone being provided. According to the invention, the workpiece is provided with a marking, the hardening device having a sensor for detecting said marking. The curve trace and the hardening device are moved relative to one another along the treatment direction until the senor detects the marking. Once the marking is detected, another movement takes place in the treatment direction before the hardening device is activated, the curve trace being hardened by the relative movement. The marking is again detected by means of the sensor and the hardening device is then deactivated. The invention also relates to an arrangement which is suitable for carrying out the method described.

Abstract: A method is provided for producing a bearing ring (1) for large-size rolling bearings including at least one track (3) that is provided with a hardened peripheral layer. With the method the peripheral layer that is to be hardened is exposed to the electric field of an inductor in order to be heated and is then quenched. At least two inductors (2) are disposed above a common zone (a) of the annular track (3) that is to be hardened at the beginning of the hardening process. These inductors (2) heat the opposite peripheral layer to a hardening temperature at this location. The inductors (2) are moved in the opposite direction along the annular track in order to heat the adjacent central zones (b). Sprinklers (5) that are directed onto the heated peripheral layers are turned on following a short distance, and the peripheral layers are quenched starting from the center of the zone (a) that was heated at the beginning.

Abstract: A method is provided for producing a bearing ring (1) for large-size rolling bearings including at least one track (3) that is provided with a hardened peripheral layer. With the method the peripheral layer that is to be hardened is exposed to the electric field of an inductor in order to be heated and is then quenched. At least two inductors (2) are disposed above a common zone (a) of the annular track (3) that is to be hardened at the beginning of the hardening process. These inductors (2) heat the opposite peripheral layer to a hardening temperature at this location. The inductors (2) are moved in the opposite direction along the annular track in order to heat the adjacent central zones (b). Sprinklers (5) that are directed onto the heated peripheral layers are turned on following a short distance, and the peripheral layers are quenched starting from the center of the zone (a) that was heated at the beginning.

Abstract: A bearing ring for a large roller bearing is formed with at least one annular race which is hardened by heating by juxtaposing that race with an inductor across a spacing which is maintained during the heating and then quenching. The spacing is controlled selectively so that it is: 1 to 2 times a depth T of hardening of the surface layer for a radial-bearing race, 0.6 to 1 times the depth T of hardening of the surface layer for an axial-bearing race whose inner diameter corresponds to an inner diameter of the bearing ring, at an outer edge of the axial-bearing race, 1.5 to 2 times the depth T of hardening of the surface layer for the axial-bearing race whose inner diameter corresponds to an inner diameter of the bearing ring at an inner edge thereof, and varying continuously between the outer edge and the inner edge, and uniformly 0.6 to 1 times the depth T of hardening of the surface layer for an axial-bearing race whose inner diameter is greater than that of the bearing ring.

Abstract: A bearing ring for a large roller bearing is formed with at least one annular race which is hardened by heating by juxtaposing that race with an inductor across a spacing which is maintained during the heating and then quenching.