Abstract: A spray quench system is provided with one or more spray quench rings that eject a controlled volume of spray onto a workpiece passing through the quench rings. The quench rings can be adjusted in position independently of each other relative to the workpiece being sprayed. Reflected spray guards may be provided to prevent spray interference between adjacent quench rings. The outlets of the quench rings may be adjustable in volume. A controller can be provided to optimize the distribution of quench cooling flows from the quench rings. Sets of quench rings with different diameters in each set may be provided in modular form.

Abstract: A method of severing a metal piece into parts in which electrical contacts engage the piece at the end of the severing line and high frequency electrical current is fed to the contacts for the length of time required to at least significantly reduce the tensile strength of the metal along the line, the current being fed to at least one of the contacts through a proximity conductor overlying the line. After such heating of the metal, the portions of the piece can merely be pulled apart. If shaping of the edge faces is desired, they can be pressed together while heated and malleable and after separation or can be pressed against an anvil while heated and malleable. Before separation, the portions on opposite sides of the line can be pushed toward each other or be moved transversely to each other. If the metal along the line is heated to "burning" temperature, the portions can be separated by burning out the heated metal with an oxygen containing gas.

Abstract: Method and apparatus for butt welding the edge faces of metal skelp which has been heated to a temperature of at least 1000.degree. F. but below the welding temperature of the metal of the skelp. The skelp is continuously advanced through a furnace in which the skelp is heated to such temperature and then, to forming rolls where the skelp is formed into a substantially complete tube with closely spaced skelp edge faces, to a spacing roll for maintaining the edge faces in closely-spaced relation and to pressure rolls where the edge faces are pressed together. Intermediate the spacing roll and the pressure rolls, the edge faces are heated to welding temperature with an induction coil fed with electrical current having a frequency of at least 10 Khz. The induction coil does not encircle the skelp in its tubular forms and instead, has legs adjacent the edge faces and at opposite sides of the gap between the edge faces.

Abstract: Methods and apparatus for manufacturing tapered, hollow metal poles which can be used for manufacturing poles of various lengths, tapers and cross-sectional dimensions with the same apparatus. A substantially complete, tapered tube is formed from a plate or sheet of metal having lips at its longitudinal side edges which extend transversely to the major surface of the plate or sheet. The tube is guided at its lip portions to a weld point where pressure is applied to force the lips together by a grooved roller which applies pressure to the oppositely facing surfaces of the lips in directions transverse to such surfaces. The lips are spaced in advance of the weld point, and high frequency, electric heating current is supplied to the tube at opposite sides of the gap between the lips to heat the tube at the lips to welding temperature as it is advanced to the weld point.

Abstract: A method of removing ripples from the metal sheet portion of a heat exchanger panel element which is manufactured by joining a metal tube to a metal sheet by means of heated and cooled weld metal, and the product of the method. In the method, the sheet is corrugated, after the tube is joined thereto, without stretching the metal of the sheet by more than 2% so that the sheet length with corrugations is substantially equal to the length of the tube joined thereto.

Abstract: Apparatus for supporting and feeding high frequency electric current to a pair of contacts for engaging a work piece or pieces and supplying current thereto in which a co-axial line has relatively movable inner and outer conductors with a pair of contacts respectively mounted at one end of each conductor, electric current being supplied to the conductors adjacent the other ends of the conductors. In one embodiment, the conductors are rotatable and the contacts are mounted on radially extending arms secured to the ends of the conductors. In other embodiments, one conductor is rotatable and the other conductor is axially movable, one contact being mounted on a radially extending arm secured to the rotatable conductor and the other contact being secured to the end of the axially movable conductor. Also, flexible lead and conductive bearing current feed systems and contact mounting arms which are readily convertible into an induction coil support.

Abstract: Method and apparatus for modifying the surface properties of a metal part made of a metal which changes its properties with heating to a transformation temperature and subsequent cooling in which method electric current having a frequency of at least 3000 Hz is supplied to a pair of contacts respectively at the opposite ends of the surface area to be modified through a proximity conductor or conductors which are spaced from the surface area by not more than two times the width of the conductor. The duration, frequency and magnitude of the current and the width of the proximity conductor or conductors are chosen so that the metal of such area heats at least to the transformation temperature before the adjacent metal reaches a temperature which would prevent self-quenching of the area metal, by means of conduction of heat from the area metal to the adjacent metal, when the current is discontinued. Apparatus for producing lines of hardening on valve seats is disclosed.

Abstract: An induction coil for the treating of metal parts where the coil carries large currents and is subjected to large forces. The coil has two layers of metal, the layer nearest the metal part being made of high conductivity and the other layer being made of a metal having an electrical conductivity less than that of copper and having a Young's Modulus at least 20% greater than the Young's Modulus of the metal of the layer nearest the metal part. The layer of metal nearest the metal part has a thickness at least equal to the reference depth of the current in such metal and preferably, has a thickness from 1.5 to 10 times such reference depth. Preferably, also, the surfaces of the other layer, except possibly those relatively remote from the principal currents, are covered by the high conductivity metal having a thickness at least equal to such reference depth.

Abstract: Methods of heating and welding together portions of a metal part or parts in which the portions are positioned in facing, generally parallel and spaced apart relation and an induction coil overlies the part or parts and is positioned so as to induce oppositely flowing currents in the part or parts which flow in two closed paths, one each side of the portions to be heated. The portions may be stationary or be advanced during heating, and after the portions reach welding temperature, they are pressed together to form a weld therebetween.

Abstract: A method and apparatus for embedding in a surface area of a metal part a plurality of particles of a material having a melting point higher than, and mechanical properties different from, the metal of the part. The metal part is contacted with a pair of contacts, one at each end of the area, and electric current having a frequency of at least 3000 Hz is supplied to the contacts through a proximity conductor or conductors which overlies or overlie the area and which are spaced from the area by not more than five times the conductor width. The current is maintained until the metal of the area reaches a temperature at least equal to the melting temperature thereof and the particles are inserted into the molten metal which is then cooled. If the temperature of the molten metal exceeds the melting temperature of the particles, the molten metal is cooled before the particles completely melt.

Abstract: Method for manufacturing heat exchange panels each comprising a plurality of sub-panels of finite length, each sub-panel comprising a metal tube welded to a metal sheet except at the end portions thereof which are secured to headers in fluid-tight relation thereto, in which method tubing and metal sheet having a length several times the length of the sub-panel are continuously advanced and welded together by high frequency electric current which is interrupted periodically so that a unit several times the length of a sub-panel and having tubing welded to the sheet by a weld which is continuous except at portions of the tubing spaced apart longitudinally by a distance substantially equal to the length of a sub-panel. The unit is cut at the unwelded portions to provide several sub-panels which are assembled to form the heat exchange panels. The metal sheet may be bent during manufacture of the unit to provide sub-panels having stiffening ribs or having projections for interlocking adjacent sub-panels.

Abstract: In-line electrical welding apparatus for welding small diameter, thin-walled, metal tubing as it is advanced longitudinally comprising a high frequency electrical current source, a pair of upstream electrical contacts connected to one terminal of the source and a pair of downstream electrical contacts connected to the other terminal of the source through a proximity conductor which extends in close relation to the edges of the tubing to be heated from the downstream contacts to adjacent the upstream contacts. The contacts are each independently movable toward and away from the tubing along paths parallel to planes parallel to and intersecting the tubing axis and at an acute angle to each other. Guiding means adjacent to the downstream contacts apply welding pressure to the tubing, and further guiding means upstream of the downstream contacts but at least as close to the weld point as the upstream contacts guide the tubing as it is advanced.

Abstract: Methods and apparatus for manufacturing welded metal tubes of finite length in which an almost complete, axially split tube is advanced into a welding head where one edge face at one side of the split is accurately positioned and clamped and then the other edge face at the opposite side of the split is pressed against the one edge face. The welding head comprises a retractable edge face guide for said one edge face, clamping devices for holding and applying pressure to the tube, a proximity conductor over and extending along the abutting edge faces and contacts engagable with the opposite ends of the tube adjacent the abutting edge faces and connected to a high frequency current source for electrically heating the metal adjacent the edge faces to forge welding temperature.

Abstract: A forming method in which members are forced together at an interface by causing parallel currents to flow in adjacent conductors, thereby forcing the conductors toward each other in a direction generally normal to the interface.