MaIntenanCe
This unit is designed for continuous operation and requires very little routine maintenance.
The bath level should be maintained regularly and periodically the bath should be emptied and the
1.
alundum screened (or replaced).
Should the fluidised bath be stored for long periods of time under damp or humid conditions,
moisture may be absorbed by the alundum which is hydroscopic. To avoid violent fluidisation which
occurs when damp alundum is heated above 100°C, operate the bath for a period of approximately
8 hours at 90°C prior to operation at elevated temperatures.
NEVER ADD COLD OR DAMP ALUNDUM TO A HOT BATH AS THIS WILL ALSO CAUSE VIOLENT
FLUIDISATION WHICH CAN BE DANGEROUS. Allow the bath to cool then add the fresh alundum.
If this fresh alundum is a large proportion of the charge then dry the whole charge as above.
Always ensure that clean, dry air is used and that the correct electrical supply is properly
2.
connected.
Periodically check the following components for damage or malfunctioning:
3.
a) Porous Plate. Check for cracks, or leakage of air through the rubber seal around
the periphery
b) Heaters. Check for bad ‘scaling’ or signs of local deterioration.
c) Energy Regulator. When switched on the contacts can be heard to ‘click’ on and off
periodically except when set at 10 position.
d) Safety Switch. When the sand bed is solid, the heater circuit should be automatically
broken. With the bed just ‘fluidised’ the heater circuit should be completed. (Both tests
should be made with the energy regulator set at 10).
Fa
uLt FInDIng
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