Abstract: An induction coil with inner and outer coil segments joined together by a transition segment is arranged so that the outer coil segment generally inductively heat treats an annular outer region of a workpiece positioned under the coil, the inner coil segment generally inductively heat treats an annular inner region of the workpiece, and the transition segment traverses at least a portion of the width of the overall annular region of the workpiece to be heat treated. Relative arrangement of inner, outer and transition coil segments provides for controlled induction heat treatment across the overall annular region such as the gear teeth region of an intersecting axes or non-intersecting and non-parallel axes gear.

Abstract: Apparatus and method are provided for inductively heating workpieces with varying characteristics in the same induction coil while selectively controlling the induced heat temperature distribution profile of each workpiece with one or more flux compensators inserted into the induction coil along with the workpiece to be inductively heated.

Abstract: Apparatus is provided for inductively heat treating a circular surface of annular workpieces where at least one inductor pair is used to perform a scan induction heat treatment of the circular surface. Controlled movement of the inductors and application of quenchant is provided particularly at the initial and final heat treatment locations on the circular surface to enhance metallurgical uniformity of the annular workpiece at these locations. In combination with controlled movement of the inductors, a simultaneous power-frequency control scheme can be applied to the inductors during the heat treatment process with the apparatus.

Abstract: Apparatus is provided for inductively heat treating a circular surface of annular workpieces where at least one inductor pair is used to perform a scan induction heat treatment of the circular surface. Controlled movement of the inductors and application of quenchant is provided particularly at the initial and final heat treatment locations on the circular surface to enhance metallurgical uniformity of the annular workpiece at these locations. In combination with controlled movement of the inductors, a simultaneous power-frequency control scheme can be applied to the inductors during the heat treatment process with the apparatus.

Abstract: An apparatus and process are provided for multi-frequency induction heat treatment of workpieces including gears. High frequency power is applied to an induction coil that surrounds the workpiece so that a high frequency magnetic field couples with the workpiece to inductively heat the workpiece. A C-core inductor is coupled to a coil that has low frequency power applied to it. The workpiece is inserted in a gap in the C-core inductor magnetic circuit so that it experiences low frequency Joule effect heating when the low frequency current is applied to the coil coupled with the C-core inductor. Alternatively the workpiece may be inserted around the C-core inductor when the workpiece has an opening.

Abstract: Apparatus and method are provided for inductively heat treating a circular surface of annular workpieces where at least one inductor pair is used to perform a scan induction heat treatment of the circular surface. Controlled movement of the inductors and application of quenchant is provided particularly at the initial and final heat treatment locations on the circular surface to enhance metallurgical uniformity of the annular workpiece at these locations. In combination with controlled movement of the inductors, a simultaneous power-frequency control scheme can be applied to the inductors during the heat treatment process.

Abstract: A cylindrical workpiece is mounted between opposing friction and non-friction guide rails and pushed through an induction coil arrangement by a pusher element positioned relative to the workpiece so that the pusher element introduces a force that moves the workpiece linearly forward within the induction coil arrangement between the two guide rails and rotationally by kinetic friction of the workpiece with the friction rail.

Abstract: A magnetic flux concentrator is used to control the end heating of a tubular material in an electric induction heat treatment process. The magnetic flux concentrator may consist of fixed elements, or a combination of fixed and moveable elements to accommodate end heating of tubular materials having different dimensions or material properties.

Abstract: Apparatus and method are provided for heat treatment of a tubular preform material that is loaded onto the outer surface of an electrically conductive mandrel forming a rotatable tubular shaped resistance heater.

Abstract: Roll forging of an annular article of manufacture is accomplished with electric induction heating of the workpiece simultaneously during the roll forging process as required to keep the workpiece at optimum forging temperature during the roll forging process.

Abstract: Large, non-unitarily forged shaft workpieces such as a crankshaft have successive shaft features inductively heated and forged without cool down between each sectional forging process. The temperature profile along the axial length of the next section of the shaft workpiece to be inductively heated and forged is measured prior to heating, and the induced heat energy along the axial length of the next section is dynamically adjusted responsive to the measured temperature profile to achieve a required pre-forge temperature distribution along the axial length of the next section prior to forging.

Abstract: Apparatus and method are provided for induction heating of one or more components of a complex-shaped workpiece. The component is positioned within an opening formed by opposing pairs of arcuate coil structures formed in opposing inductor segments. One inductor segment is formed from electrically isolated inner and outer active inductor segments connected to one or more power supplies, while the other inductor segment is formed from electrically isolated inner and outer passive inductor segments that are magnetically coupled with respective inner and outer active inductor segments. Changing the output electrical parameters of the one or more power supplies controls the induction hardening along the transverse width of the workpiece with optional flux concentrators between opposing pairs of arcuate coil structures.

Abstract: Apparatus and method are provided for inductively heat treating a circular surface of annular workpieces where at least one inductor pair is used to perform a scan induction heat treatment of the circular surface. Controlled movement of the inductors and application of quenchant is provided particularly at the initial and final heat treatment locations on the circular surface to enhance metallurgical uniformity of the annular workpiece at these locations. In combination with controlled movement of the inductors, a simultaneous power-frequency control scheme can be applied to the inductors during the heat treatment process.

Abstract: A cylindrical workpiece is mounted between opposing friction and non-friction guide rails and pushed through an induction coil arrangement by a pusher element positioned relative to the workpiece so that the pusher element introduces a force that moves the workpiece linearly forward within the induction coil arrangement between the two guide rails and rotationally by kinetic friction of the workpiece with the friction rail.

Abstract: Large, non-unitarily forged shaft workpieces such as a crankshaft have successive shaft features inductively heated and forged without cool down between each sectional forging process. The temperature profile along the axial length of the next section of the shaft workpiece to be inductively heated and forged is measured prior to heating, and the induced heat energy along the axial length of the next section is dynamically adjusted responsive to the measured temperature profile to achieve a required pre-forge temperature distribution along the axial length of the next section prior to forging.

Abstract: Apparatus and method are provided for induction heating of one or more components of a complex-shaped workpiece. The component is positioned within an opening formed by opposing pairs of arcuate coil structures formed in opposing inductor segments. One inductor segment is formed from electrically isolated inner and outer active inductor segments connected to one or more power supplies, while the other inductor segment is formed from electrically isolated inner and outer passive inductor segments that are magnetically coupled with respective inner and outer active inductor segments. Changing the output electrical parameters of the one or more power supplies controls the induction hardening along the transverse width of the workpiece with optional flux concentrators between opposing pairs of arcuate coil structures.

Abstract: Apparatus and method are provided for inductively heating workpieces with varying characteristics in the same induction coil while selectively controlling the induced heat temperature distribution profile of each workpiece with one or more flux compensators inserted into the induction coil along with the workpiece to be inductively heated.

Abstract: An induction coil with inner and outer coil segments joined together by a transition segment is arranged so that the outer coil segment generally inductively heat treats an annular outer region of a workpiece positioned under the coil, the inner coil segment generally inductively heat treats an annular inner region of the workpiece, and the transition segment traverses at least a portion of the width of the overall annular region of the workpiece to be heat treated. Relative arrangement of inner, outer and transition coil segments provides for controlled induction heat treatment across the overall annular region such as the gear teeth region of an intersecting axes or non-intersecting and non-parallel axes gear.

Abstract: A magnetic flux concentrator is used to control the end heating of a tubular material in an electric induction heat treatment process. The magnetic flux concentrator may consist of fixed elements, or a combination of fixed and moveable elements to accommodate end heating of tubular materials having different dimensions or material properties.

Abstract: A magnetic flux concentrator is used to control the end heating of a tubular material in an electric induction heat treatment process. The magnetic flux concentrator may consist of fixed elements, or a combination of fixed and moveable elements to accommodate end heating of tubular materials having different dimensions or material properties.