Abstract: Provided is a system for controlling heating of a workpiece that includes an interface to receive a target temperature (TT) for the workpiece. A processor is configured to determine, based on monitoring outputs of temperature sensor(s), a current highest temperature (TH) for the workpiece and set a control temperature (TC) based on the received target temperature and the current highest temperature. A control system is configured to heat the workpiece to substantially the control temperature (TC) by turning on a heating device, and turning off the heating device when the workpiece reaches substantially the control temperature (TC). The processor is further configured to characterize a temperature ramp rate based on a measured temperature overshoot at the workpiece after turning off the heating device, and the control system is configured to heat the workpiece to the received target temperature (TT) by controlling the heating device based on the temperature ramp rate.

Abstract: A method and apparatus for heating a workpiece. An induction heating system is used to induce magnetic fields in a workpiece to inductively heat the workpiece. The induction heating system may comprise a portable power source, a portable power source controller, a fluid-cooled induction heating cable, and a portable cooling unit. The induction heating system may be used to perform a variety of induction heating operations, including: annealing, surface hardening, heat treating, stress-relieving, curing, shrink-fitting, etc.

Abstract: The invention relates to a method for operating a shaft furnace (10). According to said method, an upper region (14) of the shaft furnace (10) is charged with raw materials which sink in the shaft furnace (10) under the influence of gravity. Part of the raw materials is melted and/or at least partially reduced by the action of the atmosphere inside the shaft furnace (10). A treatment gas is introduced in a lower region (18) of the shaft furnace (10) by means of at least one lower admission opening (32), said treatment gas at least partially influencing the atmosphere inside the shaft furnace (10). The introduction of the lower treatment gas is dynamically modulated such that, during the modulation, the operating variables, that is pressure p1 and/or volume flow (I), are varied at least temporarily over a time span of ?40 s, especially ?20 s, preferably ?5 s and especially preferably ?1 s.

Abstract: A system for producing significant quantities of noble metals from low-grade ore. A mixture of particulate feed containing small amounts of noble metals, a base metal, and activated carbon are placed in a non-conducting container. The container is surrounded by a coiled transmission line and heated via a combustion chamber. Pairs of electrical pulses having equal amplitudes and opposing directions are applied to each end of the transmission line so that the opposing pulses collide within the transmission line, the collision points traveling in a sweeping motion along the transmission line. Other pairs of pulses are sent in repeated cycles of multi-chord pulse trains, each chord having a specific frequency ranging preferably between 5000 to 7000 cycles per second.

Abstract: An induction-hardening machine for the contour hardening of machine components such as gears includes a system processor which controls thyristor power switching circuits which supply high-power signals to an RF generator. Power switching circuits include silicon controlled rectifiers of SCR's. In order to overcome the variable "on time" characteristics of SCR devices, a zero crossing detector is implemented and time periods are calculated so that the system processor activates the SCR circuits to supply power to the RF generator at predetermined times. The system processor 12 will deactivate the SCR circuits at or just prior to a zero crossing referenced from the predetermined activation time thereby effectively controlling the one time of the SCR circuits with an accuracy of up to five ten thousandths of a second. The signal produced by the RD generator is supplied to an induction heater coil which is used to case harden the gear teeth of a machine component or gear.

Abstract: Carbonaceous combustion products (i.e., principally carbon dioxide) and water are removed from nitrogen generator gas by molecular sieve adsorption thereof. The molecular sieve material is regenerated by an initial extended purging with ambient air under vacuum followed by a short burst of pure nitrogen under vacuum to remove any entrapped oxygen.