Intended Use
Types 461 and 462 are general purpose laboratory furnac-
es intended for applications requiring temperatures from
800-1700 degrees C.
General Usage
Do not use this product for anything other than its intended
usage.
Principles of Operation
The chamber section is heated by six (in type F46100 fur-
naces) or eight (in type F46200 furnaces) Super Kanthal
33 heating elements suspended in a chamber made of alu-
mina and silica high temperature refractory fiber.
This high temperature refractory fiber is in the form of
blocks which line the inside of the chamber. Because of the
stresses caused by extremely high temperature operation,
these blocks will show some surface cracking. This crack-
ing is not detrimental to the operation of the furnace.
A precious metal type B thermocouple senses the tempera-
ture in the chamber and transmits this information to the
temperature control in millivolts.
The control section consists of a temperature controller, a
current controller, a transformer, a contactor (relay), a
circuit breaker, and a pilot light.
The temperature controller senses the furnace temperature
(by means of the thermocouple) and adjusts electricity to
the heating elements by means of the current controller.
The current controller controls electricity to the heating
elements by adjusting the magnitude of the electrical cur-
rent (rather than turning the electricity completely on or off).
This is the preferred method of controlling electricity to
molybdenum disilicide heating elements.
The transformer supplies the proper electrical voltage to
the heating elements.
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General Description
