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serVICIng
Before any servicing is attempted the unit should be disconnected from the mains and allowed to cool down. In
all cases maintenance and repair work should be undertaken only by a skilled technician. Untrained personnel
should not attempt to dismantle the instrument.
Daily Maintenance (or as necessary)
Empty the cyclone collector bottle as follows (can be done whilst bath is hot):
1. Turn off the fluidisation air.
2. Turn off the dust extraction system.
3. Unscrew the bottle from the base of the cyclone unit.
4. Screw on the empty spare bottle.
5. Turn on the dust extraction system.
6. Turn on the fluidisation air until the bath is just fluidised.
7. Carefully and slowly empty the full bottle into the top of the bath. (Except for the first bottle from a new
charge which should be thrown away). Note: During normal operation the collector bottle should only
become partially full during an 8 hour period. An excessive amount of alumina in the collector bottle
suggests that the fluidised bath has been overfilled with alumina, check the level in the bath. Add enough
from the bottle to bring the bath to the correct level and keep the remainder as spare material.
8. Increase fluidisation up to the correct working level.
9. Check the filter and clean or replace if necessary, when the extraction system is switched off. (Note the screw
and the filter may be hot).
periodic Maintenance
The fluidised bath requires the following periodical inspection to be carried out to ensure trouble free
operation:
The condition of the alumina should be checked to make sure that there are no lumps and, if practical, sieved
occasionally. A fresh charge of alumina should be used if the medium is contaminated in any way.
Should the fluidised bath be stored for long periods of time under damp or humid conditions, moisture may be
absorbed by the alumina which is hydroscopic. To avoid violent fluidisation which occurs when damp alumina is
heated above 100°C, operate the bath for a period of approximately 8 hours at 90°C prior to operation at
elevated temperatures. The heaters should be checked for discolouration, oxidation or to determine if any build
up of alumina particles has taken place on the surface.
The condition of the porous plate should be checked to see whether there are any oil stains or discolourations:
if so, and fluidisation is impaired, replace the porous plate.
The air supply filter should be checked to ensure that the auto drain system is working and that the filters are in
good condition.
