Cole Parmer Techne IFB-201, Инструкция по эксплуатации

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Should the fluidised bath be stored for long periods of time under damp or humid conditions, moisture
maybe 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.
NEVER ADD COLD OR DAMP ALUMINA TO A HOT BATH AS THIS WILL ALSO CAUSE VIOLENT
FLUIDISATION WHICH CAN BE DANGEROUS. Allow the bath to cool then add the fresh alumina. If this
fresh alumina is a large proportion of the charge then dry the whole charge as above.
Set the air pressure regulator, which is situated within the pneumatic section of the control console to
204kPa (30 psi).
The following table shows the recommended fluidising air flow rates which should be used to achieve
the correct level of fluidisation.
100°C to 200°C 220 l/min
200°C to 400°C 180 l/min
400°C to 600°C 150 l/min
The figu res quoted are approximate and may need to be varied depending upon the working load, eg
the bath may have to be ‘overfluidised’ to avoid the creation of dead spots above the immersed
object.
To safeguard the fluidised bath from damage two safety features are included in the control console: an
overtemperature cut-out (set at 630°C) which guards against controller failure, and an air pressure switch
which inhibits operation if the compressed air supply to the
fluidised bath fails. Both of these devices
isolated the electrical supply to the heater elements and illuminate the cut-out indicator in a fault
condition.
If the fluidised bath is to be used to process items that may emit toxic or inflammable fumes, it is essential
that an adequate fume extraction system be installed. Details of fume cleaning equipment are contained
in the following section of this manual.
The extraction system must be adjusted during initial operation for optimum extraction in line with the
following instructions:
a) Heat the fluidised bath to the operating temperature as recommended later in this manual, ensuring
that the fluidising air flow rate is adjusted in accordance with the above table. Remember that the lid
must be fitted.
b) Switch on the fume extraction system.
c) Immerse a typical component that is to be treated into the fluidised bath; do not exceed the started
loading capacity, see Technical Specification for details.
d) Adjust the overall fume extraction rate by adjusting the setting of the damper valves built into the
fume extraction system so that adequate fume removal occurs over the surface of the fluidised bath.
The velocity of the extraction system should be just suf ficient to entrain the maximum quantity of
fumes produced above the bath. If a high extraction velocity is used, an excessive amount of fluidising
medium will be entrained by the extraction system.
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