1. THERMOCOUPLES THEORY
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3. Thermowells and protection tubes
Thermowells and protection tubes are used to shield thermo-
couple sensing elements against mechanical damage and
corrosive or contaminating atmospheres.
The various types and constructions which are available ena-
ble the user to select the right combination to meet individual
needs.
For example: cast iron protection tubes are used primarily in
molten aluminium, magnesium and zinc applications. On the
other hand, the ceramic tubes are used in industries such as:
iron and steel, glass, cement and lime processing. Their prin-
cipal advantages include: resistance to high temperatures and
thermal shock, chemical inertness, good abrasion resistance
and high dielectric strength.