Abstract: A system for use in sensing the oxygen content of an industrial furnace gas typically containing hydrocarbons or hydrogen is disclosed. The system utilizes a conventional automotive EGR oxygen sensor probe positioned in an especially configured housing employing downstream flow regulating means in combination with an orificing plate in the housing to provide uniform distribution of the endothermic gas at a low temperature about the sensor to insure accurate sensor readings with minimal carbon deposition. The electrical contacts at the oxygen sensor's inner and outer electrolyte surfaces are periodically switched to an electrical power supply to cause current to flow through and heat the electrolyte to elevated temperatures while air is flowed over the electrolyte's surfaces to achieve burn out of any carbon deposits and restore the life of the oxygen sensor probe.

Abstract: A heat treat process is disclosed for use in an ion glow discharge chamber for carburizing ferrous workpieces. The process provides rapid carburizing cycles by optimizing the power supplied to the glow discharge correlated to temperature and desired uniformity of the carbon gradient profile while also optimizing the mass flow of the substantially pure carbon bearing gas which is correlated to the desired uniformity of the carbon gradient profile.

Abstract: An improved industrial furnace employing a new and unique heat transfer arrangement is disclosed. The furnace is a closed end cylindrical chamber with a circular, concentrically positioned plate dividing one side of the furnace into a fan chamber containing a fan and the other side of the furnace into a heat treat chamber containing the work. The plate has a central under-pressure opening and its outer circular edge is spaced from the cylindrical wall to define an annular space which is non-orificing. Fan rotation in the fan chamber produces an annulus of wind mass swirling at high circumferential speed which axially travels through the non-orificing space towards the closed end of the heat treat chamber at slow speed. Heating elements extend through the non-orificing space into the heat transfer chamber and are constantly impinged by the swirling annulus wind mass to effect good heat transfer therewith.

Abstract: An internal heat exchange tube for cooling work within an industrial furnace is positioned to extend within the furnace and is closed at its axial end which is inside the furnace. Within the tube is an open ended, thin wall inner tube formed in the shape of a helical coil. Water introduced into the inner tube distributes thermally induced, circumferential stress gradients about both tubes to prevent tube bending while achieving fast cooling of the outer tube.

Abstract: An improved industrial furnace employing a new and unique heat transfer arrangement is disclosed. The furnace is a closed end cylindrical chamber with a circular, concentrically positioned plate dividing one side of the furnace into a fan chamber containing a fan and the other side of the furnace into a heat treat chamber containing the work. The plate has a central under-pressure opening and its outer circular edge is spaced from the cylindrical wall to define an annular space which is non-orificing. Fan rotation in the fan chamber produces an annulus of wind mass swirling at high circumferential speed which axially travels through the non-orificing space towards the closed end of the heat treat chamber at slow speed. Heating elements extend through the non-orificing space into the heat transfer chamber and are constantly impinged by the swirling annulus wind mass to effect good heat transfer therewith.

Abstract: An internal heat exchange tube for cooling work within an industrial furnace is positioned to extend within the furnace and is closed at its axial end which is inside the furnace. Within the tube is an open ended, thin wall inner tube formed in the shape of a helical coil. Water introduced into the inner tube distributes thermally induced, circumferential stress gradients about both tubes to prevent tube bending while achieving fast cooling of the outer tube.

Abstract: A low cost, improved convective heat transfer furnace is disclosed which includes a cylindrical casing to which is attached blanket insulation and the casing is closed at its ends to define a closed end cylindrical furnace enclosure. An annular fan face plate is positioned within the enclosure to define a pressure zone on one side and a work zone on the other side. A paddle wheel fan in the work zone develops a large mass of circumferentially swirling wind which is initially formed as a stationary swirling mass without an axial force component but which under pressure travels axially in the form of a swirling annulus through the non-orificing annular space. The under pressure zone established by the central opening in the fan face plate causes the swirling wind annulus in the work zone to expand radially inwardly and uniformly impinge the complete surface of the work in an effective heat transfer manner before being recirculated back to the pressure zone.

Abstract: A semi-continuous pyrolysis arrangement is disclosed which is particularly useful in the reclamation of a base material in a substantially pure form from a composite material which has organic compounds. The furnace base barrier free zones wherein the waste material is continuously pyrolyzed as it is indexed through the furnace and each zone is controlled in a preset manner established from pyrolyzing a sample waste specimen under controlled conditions. Preferably, the waste is containerized as a particulate solid in discrete static beds permitting a fan exhaust arrangement to establish convective heat transfer with the bed while also establishing the furnace zones. An exothermic zone is provided at the end of the furnace to remove fixed carbon from the pyrolyzed waste by bleeding substoichiometric amounts of air in an oxygen temperature controlled manner to permit recovery of the waste in a substantially pure form.

Abstract: Method and apparatus is disclosed for thermally decomposing waste material from several batch furnaces plumbed into one afterburner. The afterburner is modified to mix and combust in a controlled manner an otherwise explosive mixture of fumes from several furnaces. The entire system is regulated only by the temperature of incinerated gases from the afterburner. The furnaces are operated in a sequenced, overlapping staged manner to produce a generally constant fume loading permitting significant cost savings in equipment and operation.

Abstract: A heat treat process is disclosed for use in an ion glow discharge chamber for carburizing ferrous workpieces. The process provides rapid carburizing cycles by optimizing the power supplied to the glow discharge correlated to temperature and desired uniformity of the carbon gradient profile while also optimizing the mass flow of the substantially pure carbon bearing gas which is correlated to the desired uniformity of the carbon gradient profile.

Abstract: An inside-outside quench arrangement is disclosed for long steel pipe which utilizes a tangential quench arrangement to cool the pipe's outside surface and an axial flow nozzle to cool the pipe's inside surface at approximately the same cooling rate. The O.D. quench arrangement includes a manifold carrying jet nozzles circumscribing the pipe which can be pivoted apart to permit a four-bar linkage mechanism to smoothly and efficiently transfer the pipe into and out of the arrangement for quenching. A roller drive arrangement rotates the pipe in a longitudinally stationary position to minimize pipe bow and enhance pipe cooling.