Abstract: The invention relates to a device for hardening the surface of workpieces of different lengths, having: two clamping heads and a rotary drive, for clamping and rotating the workpiece to be hardened; inductors for the electroinductive heating of the workpiece surface; and a quenching spray.The characterizing feature of the invention is that disposed on opposite sides of the workpiece with provision for displacement in relation to one another in the direction of the workpiece axis for adaptation to the particular workpiece length are two line inductors (1a, 1b), each having two parallel conductor portions (2a, 2b) and end portions (5, 6) which are bent at right angles and an end portion (6a, 6b) of each of which extends arcuately or polygonally, more particularly at right angles, over the workpiece (4).

Abstract: An apparatus for inductive hardening different types of production parts, such as automobile axles, in a device of the type having a pair of rotatable spiders with a plurality of arms for clamping therebetween the parts for indexing movement from a clamping station to a releasing station, the parts being sequentially presented to the clamping station by a lifting bar conveyor. The type of part presented for clamping and type of part which the arms at the clamping station can clamp are compared and the part only clamped when the types are the same.