Hornos

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INDUSTRIAL HEATING PROCESSES
1.1. INDUSTRIAL PROCESS HEATING FURNACES Industrial process heating furnaces are insulated enclosures designed to deliver heat to loads for many forms of heatprocessing. Melting ferrous metals and glasses requires very high temperatures,* and may involve erosive and corrosive conditions. Shaping operations use high temperatures* to soften many materials forprocesses such as forging, swedging, rolling, pressing, bending, and extruding. Treating may use midrange temperatures* to physically change crystalline structures or chemically (metallurgically) altersurface compounds, including hardening or relieving strains in metals, or modifying their ductility. These include aging, annealing, austenitizing, carburizing, hardening, malleablizing, martinizing,nitriding, sintering, spheroidizing, stress-relieving, and tempering. Industrial processes that use low temperatures* include drying, polymerizing, and other chemical changes. Although Professor Trinks’early editions related mostly to metal heating, particularly steel heating, his later editions (and especially this sixth edition) broaden the scope to heating other materials. Though the text may notspecifically mention other materials, readers will find much of the content of this edition applicable to a variety of industrial processes. Industrial furnaces that do not “show color,” that is, inwhich the temperature is below 1200 F (650 C), are commonly called “ovens” in North America. However, the dividing line between ovens and furnaces is not sharp, for example, coke ovens operate attemperatures above 2200 F (1478 C). In Europe, many “furnaces” are termed “ovens.” In the ceramic industry, furnaces are called “kilns.” In the petrochem and CPI (chemical process industries), furnaces maybe termed “heaters,” “kilns,” “afterburners,” “incinerators,” or “destructors.” The “furnace” of a boiler is its ‘firebox’ or ‘combustion chamber,’ or a fire-tube boiler’s ‘Morrison tube.’
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