Excessive operating temperatures should be avoided as they increase the fume concentration above the
bath and may result in the formation of condensed fumes within the extraction system.
Material
Burn-off temperature (°C)
Nylon
450
Paint
475-575
Polythene
450-500
Polypropylene
425-500
PTFE
500
PVC
450-500
Silicone rubber
550
Ethylene methacrylic
450-480
Polyurethane
440-450
Rubber de-bonding
350 (de-bonding)
Polycarbonate
400-425
Polystyrene
450
Organic matter oil/grease
450-500
High density polythene
450
Polyesters
450
Fluoropolymers
500
Styrene
450
Table 2: Recommended operating temperatures for various polymers.
CAUTION
Care should be taken when handling hot parts which have been removed from a fluidised bath. We
recommend that protective clothing (safety glasses, etc.) be worn when working with fluidised baths and
that the installation and maintenance procedures outlined in this booklet be followed explicitly.
FUME IGNITION
Spontaneous ignition may occur above the surface of the fluidised bath or within the exhaust ductwork if
the fume concentration exceeds the lower explosive limit.
The fume concentration is dependent upon the rate of fume production in the fluidised bath and the level
of dilution achieved by entraining air from above the bath or through the dilution tee.
The rate of fume production is dependent upon the type and amount of material being treated and the
temperature of the bath.
To ensure that the concentration of inflammable fumes is below the lower explosive limit, ensure that the
amount of combustible material immersed in the bath at any one time is within the design capacity of the
extraction system.
Ensure that the temperature of the bath is at minimum level to which satisfactory results can be achieved.
Increased working temperatures result in increased fume concentration. By way of example, an extraction
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