Furnace Loading - Barnstead F46110CM Operation Manual

Furnace Loading

Furnace Loading:
Be sure to use care in loading and unloading the furnace
chamber. Molybdenum disilicide heating elements are
extremely fragile and can crack or break with just a slight
bump. Be sure not to block the flow of radiant heat from
the heating elements to the thermocouple. The thermo-
couple must be able to respond directly to the heating
elements. Failure to observe this will permit the heating
elements to overheat and possibly burn out. Poor
temperature control can also result from improper
loading.
Because of the possibility of erosion of the insulation on
the floor of the furnace chamber, a separate hearth plate
should be used when possible.
In general, space should be left on all sides of a load or
on all sides of individual components of a load so that
heat can penetrate through the surfaces. The load should
not occupy more than two-thirds of the inside dimensions
of the chamber.
The extent to which a furnace may be loaded depends
upon such factors as operating temperature, desired
accuracy, and type of material. A furnace may be loaded
more heavily at lower temperatures, if highest accuracy
is not needed, and if the material of the load absorbs
heat easily.
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