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If the refractory is thinner than specified, the thermocouple will extend past the refractory hot face. This
could increase the possibility of breakage due to thermal shock. Contact Delta Controls to arrange for a
thermocouple that is correctly sized for the installation.
6. Refractory firebrick has separated from the insulating castable –
It is not uncommon for the firebrick
to sag and form a gap between the firebrick and the castable or insulating brick. Often, thermal expansion
will cause this gap to close by itself when the furnace reaches operating temperature. If this is the only
cause of dimensional discrepancy, thermocouple installation may proceed.
7. Refractory has separated from the vessel shell
– This condition is not common, but it is possible for a
gap to appear between the insulating refractory and the vessel shell. The result is that the thermocouple
may not extend far enough into the vessel to reach the refractory hot face and may report erroneously low
temperatures. In general, this gap will not close up at operating temperatures. The thermocouple must be
re-sized to account for the gap. Contact Delta Controls to arrange for a thermocouple that is correctly sized
for the installation.
