workpiece 72 in the form of a bearing sleeve having an interior bore 73 the interior bore 73 includes a pair of bearing support races 74 and 75 with a straddle 76 separating the two bearing races surfaces because the straddle 76 has a smaller inner diameter than the rest of the interior bore 73 the inductor head 12 must be made with a maximum outer diameter small enough to allow it to be moved through the straddle this means that the inductor head 12 cannot be positioned any closer to the bearing races than is shown in fig5 this would ordinarily make it difficult to provide a contoured heating pattern in which the straddle 76 is not heated to a substantial depth in other words an ordinary inductor head would necessarily provide a heating pattern that extends relatively deeply into the straddle due to the close proximity between the straddle and the inductor head in accordance with the present invention however the presence of the secondary coil formed by the middle diverter ring 30 creates a countering magnetic flux that shapes the heating pattern produced by the two loops of the primarily coil the countering flux influence produced by the middle diverter ring tends to repel the flux field away from the location of the straddle as a result the two loops of the primary coil produce heating.