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FURNACE TEMPERATURES USED FOR MANUFACTURING

In all heat-treating practices and in a number of different situations, some equipment are necessary for measuring temperatures.

Mercury boils at 357*C, and thus cannot be used above this temperature. Most of  the heat-treatments involve temperatures well above 357*C, so this places a severe limitation on the use of mercury thermometers. They may be suitable for heat treatments which are carried out below this temperature. 


furnace

A scientific and reliable method of  measuring temperatures is by an instrument called pyrometer. 

Two types of pyrometers in common use are :

1. Thermoelectric pyrometers.

2. Optical Pyrometers.


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