Abstract: Heating element assemblies, heating furnaces incorporating heating element assemblies, methods to form heating element assemblies, methods to form heating furnaces and methods to reduce a magnetic field in a bifilar coil are disclosed. The heating element assembly includes two components, each component formed from heating element wire. The two components are spatially positioned and electrically arranged, relative to each other, so that an electrical current applied to the heating element assembly simultaneously travels through the two components in opposite directions.

Abstract: A method and system for cleaning the silicon microlenses in an electron-beam microcolumn in situ. The microlenses individually are heated by passing a current through each microlens. The current is utilized to heat the microlens to at least two hundred degrees Centigrade to prevent contamination and occasionally to a temperature on the order of six to seven hundred degrees Centigrade to remove any builtup or potential contamination.

Abstract: A galvanizing apparatus comprising a vessel for containing a melt of molten metal. The vessel includes at least one conical projection in its side walls around which an induction heating coil is wound to generate a uniform and continuous stirring pattern of molten metal that penetrates deeply into the pot. In a second embodiment, the galvanizing vessel has no projections from its side walls, but comprises instead one or more flat inductors disposed on the exterior wall of the vessel. The flat inductor is surrounded by magnetic return shunts for directing the magnetic force field created by the inductor.

Abstract: An induction heating apparatus having a refractory vessel for holding a quantity of material to be heated by the apparatus. The vessel being surrounded by, but does not touch, an induction coil having a plurality of helical turns. The turns of the induction coil have a surface on which is disposed a layer of high temperature superconducting material.

Abstract: A water-cooled plasma torch specially designed to drill into a refractory material is used in a method for opening a tap hole closed by a plug in a wall of a furnace. This method which is particularly well adapted for robotization, includes the step of melting and breaking up the plug closing the tap hole by means of a jet of swirling gas of high speed and high temperature, generated by the plasma torch. The main advantage of this method is that the stream of plasma gas leaving the torch has a well defined outline ensuring precise and reproducible tapping of the plug and, as a result, efficient closing of the tap hole with a new plug after the furnace has been emptied.

Abstract: High temperature furnaces are described containing a movable viewing window that is heated so that the work charge can be scanned along the length of the furnace without creating a thermal disturbance. A system is also disclosed for controlling the operation of the furnace based on comparison of viewed images with stored sample images.

Abstract: High temperature furnaces are described containing a movable viewing window that is heated so that the work charge can be scanned along the length of the furnace without creating a thermal disturbance. A system is also disclosed for controlling the operation of the furnace based on comparison of viewed images with stored sample images.

Abstract: The invention concerns a means for separating molten particles from the exhaust gases of metallurgical furnaces and for returning them to the furnace space (3). As taught by the invention, a molten dust cyclone has been provided substantially within the furnace space (3) or in its immediate vicinity, this cyclone comprising a vertical cylindrical chamber (4), a passage (8) leading from the furnace space (3) tangentially to chamber (4), an exit aperture (5) in the upper part of the chamber for removing the gas and a tap aperture (6) in the lower part of the chamber for returning to the furnace space (3) the solid and molten material that has separated from the gas.The invention furthermore concerns a way recover lead from the exhaust gases of a metallurgical furnace by regulating the oxygen partial pressure in the exhaust gases to be in the range of about 10.sup.-16 to 10.sup.-10 atmospheres at temperature 1250.degree.-1450.degree. K.

Abstract: This invention is the new use of a Laser light beam directed into a metal fire pot as the combined heater element causing oxidation of the metal fire pot, for a heating system.