Abstract: Method and apparatus for melting rod-shaped material 12. This is continuously displaced in the direction of the rod axis towards an induction coil (5), disposed at the lower end (12a) of the rod, which has an opening coaxial with the rod and which is supplied with an alternating current. An induction coil (5) is used of which the axial dimension is several times smaller than the radial dimension. Preferably, a so-called flat-coil is used. The induction coil has an opening (5c) which is smaller than the rod diameter. On melting the lower end (12a) of the rod is held with its end face at a substantially constant spacing above the induction coil (5). The method and apparatus are suitable for the production of metal powder and for the direct production of shaped parts.

Abstract: An induction heating device is provided which can be easily and inexpensively modified to inductively heat and quench harden workpiece bores of various diameters. The device consists of a permanently mounted mandrel and easily interchangeable inductor coil and quench modules which can be easily and rigidly connected to the mandrel.

Abstract: A method and apparatus of quench hardening to a desired depth the full axial extent of the wall surface, or selected portions of the wall surface, of an axially extending bore in an elongated workpiece wherein the bore has a selected uniform cross-sectional shape throughout the length thereof and is closed at one end, which method and apparatus involves providing an inductor with an outer shape generally matching but smaller than the cross-sectional shape of the bore to permit passage of the inductor through the bore, supporting the workpiece with the axis of the bore extending vertically and the open end facing downward, electrically energizing the inductor with a known frequency and at a selected power level, passing the energized inductor upwardly through the bore to inductively heat the wall surface of the bore progressively upwardly from the lower end thereof while progressively liquid quenching the wall surface immediately below the inductor during the upward passage thereof through the bore, and direct

Abstract: A camshaft heat treating apparatus for processing a plurality of camshaft designs, which camshaft identifies and thereafter automatically inductively heats, quenches and inspects the camshaft in accordance with its design parameters.

Abstract: A method and apparatus for heat treating camshafts includes a retractable shield positioned between a previously hardened surface and a surface being heat treated. During the induction heating and quenching cycle, a coolant is delivered to the hardened surface to maintain the temperature thereof below the tempering temperature. The shield prevents the coolant from contacting the unhardened surface and interfering with the heating and quenching thereof.

Abstract: Thin walled broached parts are heat treated from manufactured dimensions to predetermined dimensions through control of heating, cooling and pressurization parameters during the heat treating cycle.

Abstract: The invention relates to a method of heating a piping arrangement and a heating coil used in the heating process by heating pipes through a high frequency wave induction. A spacing between the pipe outer surface and the heating coil is varied in compliance with a change in configuration of the heating coil. According to the invention, even if the coil configuration is particularly changed, it is possible to heat the pipes uniformly to obtain a uniform temperature distribution.

Abstract: An induction heating apparatus particularly adapted for precisely positioning the inductor relative to the workpiece before initiating the heating process. The inductor is mounted on the end of an inductor shaft that is carried by a slide. The end of the shaft opposite the inductor is connected to a coupling that couples the shaft to a stepping motor. The slide moves the inductor into engagement with the workpiece and the stepping motor is then energized to move the inductor away from the workpiece the required amount to obtain the desired spacing.

Abstract: Apparatus for inductively heating a non-rotating workpiece includes a rotatable spindle of insulating material having a split-ring secondary mounted thereon for rotation therewith and which secondary has opposite ends electrically connected in series with the opposite ends of a multiple turn inductor coil. A primary winding in the form of a split-ring is supported in fixed coaxial relationship with respect to the spindle and the secondary ring thereon, and opposite ends of the primary ring are connected across a source of high frequency alternating current. The apparatus is mounted on a slide for displacement toward and away from a workpiece to selectively position the inductor in magnetically coupled relationship with the workpiece, whereby the workpiece is inductively heated in response to rotation of the spindle and energization of the primary ring.

Abstract: A method and apparatus for hardening a small internal passage in a workpiece wherein the workpiece is indexed into coaxial alignment between axially spaced inductor coils and an actuator telescopically inserts a magnetically permeable flux concentrating rod through the passage, and coextensive with the coils and in inductive relationship with the interior surface, such that upon energization of the coils, flux is concentrated in the concentrating rod and effectively inductively delivered to the surface to raise the temperature thereof to a heat treating temperature, the actuator being extended to another position wherein a quenching ring is disposed adjacent to the surface for delivering coolant thereto to quench harden the surface, the actuator being finally retracted to allow sequential indexing of workpieces.

Abstract: Herein disclosed are a method of heat-treating a weld zone of a piping system, in which the outer wall of a pipe is heated by means of a heating coil, while a coolant is present in said pipe, to establish a temperature difference between the inner and outer walls of said pipe thereby to prevent the weld zone of said pipe from corroding and cracking due to stress, and a heating coil therefor. The aforementioned heating coil is wound on the parent tube and the pipe welding desk generally concentrically thereof thereby to heat substantially uniformly all over the region of said weld zone.

Abstract: A method and apparatus of quench hardening to a desired depth the inner surface of an axially extending bore in an elongated, thin-walled workpiece having an outer, axially extending surface wherein the bore has a selected, uniform cross-sectional shape, which method and apparatus involves providing an inductor with an outer shape generally matching, but smaller than, the cross-sectional shape of the bore, supporting the workpiece with the axis entending vertically, energizing the inductor with a known frequency and at a selected power level, moving the energized inductor downwardly through the bore to inductively heat the inner surface progressively while applying no fluid quench to the inner surface, letting the workpiece cool and then moving the inductor upwardly through the bore to progressively heat the inner surface while progressively liquid quenching the inner surface immediately below and after the progressive heating operation.

Abstract: An inductor for heating rotating metal workpieces, especially for surface hardening the running surfaces, transition radii and shoulders of camshafts to different depths, has two or more heating regions which can be brought into the required heating position by changing the direction of rotation of the workpieces and, when the inductor has more than two heating regions, by using a movable abutment. When the inductor has two heating regions, then change from one region to another is achieved by simply changing the direction of workpiece rotation so that friction causes the inductor to be displaced. When the inductor has, for example, three heating regions (13, 14, 15), then an abutment (11) is used to control the inductor displacement. For more rapid displacement of the inductor or for cases where the workpiece is stationary, an external pusher device may be used.

Abstract: A method and apparatus for compensating for axial deformation of screw shafts due to heat treatment, wherein in the process of hardening of a screw shaft, the screw shaft is twisted to produce permanent twist deformation by an amount corresponding to the pitch error of the screw shaft caused by hardening, so as to correct the pitch error.

Abstract: A method and apparatus for heating a conical valve seat surface of a valve seat ring insert which has been previously press fitted or molded into an engine component such as an engine head. The method and apparatus includes mounting an inductor for reciprocal movement axially toward and away from the valve seat of the engine head and biasing the inductor toward the valve seat, encircling the inductor with an axially biased electrically conducting hollow ring-shaped magnetic flux shield through which a coolant is circulated, and moving the inductor and conducting ring shield toward the valve seat of the engine head to locate the inductor in a preselected position providing the necessary magnetic coupling gap between the inductor and valve seat surface of the valve seat insert while the conducting ring shield is maintained in heat transfer surface contact with and stray flux shielding relation to the portion of the engine head immediately around the valve seat surface of the insert.

Abstract: In the manufacture of tubing, and particularly finned tubing, for use by the heat transfer industry in the manufacture of heat exchangers, annealed ends and lands are desirable in certain applications to facilitate the assembly of the tubes to headers and baffles by expanding techniques. Such spot-annealed portions can be produced on a continuous basis by the described apparatus in which the moving tube is passed through a heating chamber which reciprocates on a carriage in the direction of tube movement. The heating chamber has a pair of spaced, power-actuated clamps which grip the tubing at the ends of a discrete length portion. The heating chamber and carriage are moved with the tube while it is clamped to provide sufficient heating time to anneal the discrete length portion. The carriage then returns to its starting position. Heating of the discrete clamped tubing portion can be by a resistance technique through the clamps or by other techniques such as induction heating or gas radiant heat.

Abstract: A method for relieving stress in the microstructure welds and the heat affected zone in the adjacent base metal in low alloy steel by induction heating in a second post-weld heat treatment. The heated area is monitored with a radiation pyrometer to ensure precise temperature control of the procedure.

Abstract: This invention relates to a process and apparatus for hot working metals whereby a finer and more uniform grain structure is produced in the wrought product. In conventional hot working operations, the workpiece is initially heated to an elevated temperature within the hot working temperature range of the particular metal or alloy, and the heated workpiece is then hot worked by deformation until the workpiece becomes chilled, thereby necessitating reheating prior to further hot working. In accordance with the present invention, the reheating of the workpiece is accomplished by subjecting the chilled workpiece to electric induction heating at a frequency preselected to concentrate the induced heat in the chilled outer portions of the workpiece to thereby rapidly return the workpiece to the optimum hot working temperature throughout so that continued hot working can be reinitiated before appreciable grain growth can occur.

Abstract: Selective heating of edge and near-edge portions of a strip material is used to increase the ductility of the strip material at these portions and to improve the cold rollability and/or strip annealability of the strip material. The selective heating may be performed either by radiant heating or by induction heating.

Abstract: A process and apparatus for cleanly and efficiently fabricating winged lawn mower blades from unfinished milled blade blanks. The unfinished blades are positioned in a magazine and fed one after the other to a heating station where they are inductively heated from one side only to increase the effective thickness of material available to support the flux. When a preselected temperature above the curie temperature of the blade metal is reached the blade is automatically moved to a press and hot-formed therein. The blade then is delivered edgewise into an agitated non-polluting quench solution containing polyalkylene glycol and vigorously sprayed to assure a consistent Rockwell C hardness. A conveyor delivers the blades from the quench tank to a tempering furnace for further heat-treatment.

Abstract: In a preferred embodiment a surface layer of a thin-walled, hollow, cylindrical steel body is hardened while controlling thermal distortion by first heating with an inductor and quenching in one direction over the surface and then repeating the process in the reverse direction.

Abstract: A method and apparatus for quenching heated elongated workpieces by rotatably mounting the heated workpiece in a quench tank and subsequently rapidly flooding the tank with a quenching liquid. The heated workpiece is mounted within the quench tank by engaging opposite axial ends of the elongated workpiece. Transverse deflection of the workpiece is prevented by paired restraints located adjacent the top and bottom of the workpiece near the opposite ends. As the quenching liquid is flooded into the quench tank from a storage tank, the heated elongated workpiece is rotated about its central axis at a fixed speed.

Abstract: An induction heating inductor is provided for use in a slot type of furnace to heat axially spaced portions of an elongated workpiece. This inductor includes first and second generally rigid, elongated input members normally fixed with respect to each other and extending generally parallel to the workpiece and a conductor unit extending between the input members to define one of the heating portions and adjustable for changing the position of this heating portion on the workpiece.

Abstract: An induction heating unit is disclosed which is operable to inductively heat and harden teeth on circumferentially extending radially thin flange segments of a gear. The unit includes an inductor conforming in circumferential contour and length to the flange segment and having radially and axially offset conductor leg portions to control heating of the gear teeth during relative axial scanning movement between the gear and inductor so as to prevent distortion of the gear flange. The unit further includes an arrangement for quenching the gear teeth and cooling the end portions of the flange segment during scanning movements.

Abstract: An inductor for heating the circumferentially opposed working surfaces and the root surface between adjacent gear teeth includes a nose portion received between the adjacent teeth and having a profile corresponding to that of the working and root surfaces. The nose portion is comprised of a flux concentrator having axially opposite ends and radially inner and outer ends, a generally V-shaped conductor plate having ends attached to the radial inner end of the concentrator and defining a coolant passageway therewith, and tubular conductors at the axially opposite ends of the flux concentrator and plate to provide for the circulation of coolant through the nose portion. A portion of the tubular conductor extends axially adjacent the radially outer side of the flux concentrator.

Abstract: A method of heating metal workpieces so as to minimize scale formation and decarburization using an electroinduction heater, comprises placing the workpiece in the vicinity of the induction heater, reducing the air present in the vicinity of the workpiece to provide a reduced air atmosphere, and heating the metal by an electroinduction heater in the reduced air atmosphere. The air is advantageously displaced by a protective gas and this is done before the workpiece is heated to a temperature of 350.degree. C. A device for carrying out the heating, comprises a thermally insulated hood which has an interior heating cavity which opens downwardly and which is made gas-proof at its sides and top. A thermally insulated bottom fits into the opening of the hood and substantially fills the cavity and it is provided with a support area for the workpiece which, when the bottom is inserted, is positioned alongside the electroinduction heater.

Abstract: A process and an apparatus for producing low-oxygen iron-base metallic powder are disclosed. The low-oxygen iron-base metallic powder is produced by alloying and/or admixing iron-base metallic raw powder to be subjected to a final reduction, which has an apparent density in filled state corresponding to 16-57% of theoretical true density, an oxygen content of not more than 6% by weight and a particle size of not more than 1 mm, with carbon or carbonaceous granule in an amount corresponding to not more than an target alloying carbon content of a final product (% by weight) + an oxygen content of the powder just before the final reduction (% by weight) .times. 1.35 to form a starting powder, preheating the starting powder at a temperature of 780.degree.-1,130.degree. C. in a non-oxidizing atmosphere having a theoretical oxygen partial pressure of not more than 2.1.times.10.sup.-1 mmHg and a dew point of not more than +5.degree. C.

Abstract: A shaft furnace for producing low-oxygen iron-base metallic powder for metallurgy is disclosed. The shaft furnace comprises a zone of storing and feeding a metallic raw powder, a preheating zone, an induction heating zone and a zone of cutting and cooling a product cake in a vertical array from top to bottom. The preheating zone and induction heating zone have a special structure for ensuring a smooth descent of the raw powder and the cake.

Abstract: In a method of continuously heating wire by induction, a short circuit electrical connection between wire entering a loop or loops, constituting the secondary winding of a transformer, and wire leaving the loop or loops is effcted by guiding a portion of advancing wire on to one of two pulleys, arranged on opposite sides of the transformer core, and guiding a portion of the advancing wire off this pulley in such a way that the portions of wire cross, but are not intertwined with, one another to form the loop or loops. The advancing wire entering and leaving the loop or loops is maintained under such tension that the position in space of the crossover is substantially constant and that the cross portions of the advancing wire are in continuous physical contact, the contact pressure at the position of crossover being sufficient to disturb any electrically non-conductive layers on the wire to provide clean portions for electrical contact.

Abstract: The apparatus is provided with a manifold-type means of feeding gas into the bore of the treated object and a means of discharging gas from the bore of this object which are secured as cantilevers to brackets of a frame. These means are provided with drives enabling them to displace longitudinally so as to assure the clamping of the treated object therebetween at the end faces. The apparatus is also provided with a drive causing the treated object to rotate integrally with said means. Contrivances serving to heat up and subsequently to cool down the treated object are mounted on a platform which is installed on horizontal guides and is provided with a drive for longitudinal travel.

Abstract: An apparatus for inductively hardening by quenching of the running surface of bearings of a crankshaft in which the crankshafts are transported by a lifter-conveyor system to a clamp which grips the crankshaft and is pivoted about a lever arm pivotably mounted on the machine frame to a heating position below a plurality of inductors. The inductors ride on the crankshaft as it rotates to inductively heat the running surfaces. The inductors are each mounted on a linkage which also mounts a quenching shower and the linkage in turn is swingably mounted on a further lever arm which is pivotably connected to the machine frame. As the crankshaft rotates, the inductor lifts and the further lever arm lifts off a stop. The apparatus preferably includes a second clamp and set of inductors to which the crankshaft is subsequently conveyed for further treatment after hardening.

Abstract: A device for directing quench fluid onto the top of an inductively heated surface portion of a rotating workpiece has a supply means having an outlet end spaced horizontally from said surface portion for directing a jet of quench fluid therefrom and a deflector for intercepting and guiding the quench fluid jet onto the top of the heated surface portion of the workpiece. The spacing of the outlet end horizontally from the heated workpiece surface portion prevents the falling thereonto and contacting therewith of any drippage of residual quench fluid from the outlet end following shut-off of the supply of quench fluid thereto and during subsequent inductive reheating of the quench hardened surface portion to temper it.

Abstract: In the heat treatment (quenching treatment, tempering treatment, etc.) of long metallic material, such as, large diameter steel pipe or the like, in order to stabilize the speed of travel of the material through a heat treating zone, i.e., a zone including a heating unit, such as, an induction heating coil or gas burning type heating furnace and a following cooling unit of the type utilizing either one or both of air blast and water cooling, the material is gripped by two cars which are arranged respectively at the entry and delivery ends of the zone and the cars are moved, while supporting the material by a plurality of free rotatable rollers, so as to move the material at a desired speed. In this case, one of the cars is driven and the other car applies a braking force, thus moving the material at the desired speed through the zone.

Abstract: An apparatus for surface hardening an irregularly shaped workpiece made of hardenable material by inductive heating whereby a clamped workpiece is rotated past a linear conductor disposed along the envelope circle formed by the cam of the workpiece which extends farthest from the workpiece axis. The conductor has a plurality of yoke sheets to heat the workpiece surface uniformly.

Abstract: Transfer apparatus for performing heat treating operations on both ends of a hammer head includes a dial indexing table having work supporting fixtures spaced about its perimeter.

Abstract: There is provided a method and apparatus for inductively heating elongated workpieces having a central axis and mounted in workpiece receiving stations of an indexable turret. A single shot inductor located within the path generally followed by the indexing workpieces is used to heat the workpieces. One of the turret stations, when empty, is indexed past the single shot inductor in a first direction and is loaded with a workpiece. Thereafter, the loaded station is indexed in a second direction into the heating position with the workpiece located in the single shot inductor. Thereafter, the workpiece is indexed from the single shot inductor for subsequent processing on the turret.

Abstract: Apparatus for quench hardening the surface of a previously inductively heated, elongated workpiece as it moves along a feed path, this apparatus comprises a quenching means surrounding the feed path, the quenching means includes an inwardly facing apertured wall facing the feed path, means for forcing a quenching liquid through the apertured wall toward the feed path for quenching the surface of the heated workpiece as it passes along the feed path and means for moving the apertured workpiece in a direction generally transverse to the feed path. In the preferred embodiment, the apertured wall is generally circular and is rotated around the workpiece.

Abstract: A method and apparatus for inductively heating the axial, generally circular end of at least two elongated workpieces having central axes wherein the ends terminate in generally flat surfaces perpendicular to the axes. The method and apparatus includes locating the workpieces in side-by-side relationship with the axial ends facing a given direction and the respective axes being generally parallel, providing generally circular inductors matching each of the ends of the workpieces and normally spaced axially therefrom, moving the inductors axially of the workpieces until each of the inductors contacts the flat surface of one of the axial ends, locking the inductors with respect to each other, retracting the locked inductors axially away from the flat surfaces a selected air gap distance, rotating the workpiece about the axes and energizing the inductors to inductively heat the axial ends of the workpieces preparatory to hardening.