What are the Heat - Treating Furnaces ?

Furnaces which are used for heat-treating metals may be classified as :

Heat Treatment involves, at all events in its main stages, raising the metal to a correct temperature in a furnace fired or heated by various methods. The fuel used may be coke, coal, gas (town, blast-furnace, or natural), fuel oil, or electricity. Gas and oil are in common use for heat-treatment of large workpieces. A gas fired furnace is most suitable for heating up to about 1100*C. In recent years with the availability of cheap electric power, electrically heated furnaces have gained steadily in popularity. The advantages claimed for them are simplicity, economy, precision of temperature control, high thermal efficiency, cleanliness of operations, and saving of space. The close amount of scaling and deoxidation of the surface of workpiece is also considerably easier in electrically heated furnaces. Electricity is principally used where the temperatures required are not about 1100*C

Both types of furnaces should include automatic temperature regulators so that a control of temperature can be maintained. Accurate temperature control is a primary requisite for a furnace for the heat treatment of metal, and particularly that of aluminum alloys.

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