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Functional description
Step
Procedure
Processing instructions
1.
When heating the furnace for the first time, small amounts of water can flow from
the insulation (fibre insulation, hygroscopic).
2.
The heating element is designed to stand a maximum furnace temperature of
1600°C (HTR.....-.../16), of 1700°C (HTR.....-.../17) or of 1800°C (HTR.....-.../18).
Temperatures exceeding this limit by only 20° may shorten the service life of the
furnace considerably.
3.
The maximum heating-up rate of the furnace depends on the size of the ceramic
working pipe (accessories). Below, you will find the recommended heating-up rates
for pipes of:
•
an external diameter of up to 100mm, heating-up rate of 300K/h
•
an external diameter of up to 150mm, heating-up rate of 120K/h
•
an external diameter of up to 200mm, heating-up rate of 80K/h
•
an external diameter of more than 200mm, heating-up rate of 50K/h
When cooling down and using APM working pipes it is possible to double the
value.
If you use a quartz glass tube: The tube must not operate higher as 1050°C.
For a short time you can operate with 1100°C.
4.
If the furnace is installed in an outlet, check if the chemical vapours can
generate in the outlet. Even only slight chemical loads can strongly decrease
the working temperature.
5.
Regulators, which are configured with the thermocouple type B, will show a
temperature of -2°C on the display after switching on, without the furnace having
been heated. Small thermoelectric voltages of the thermocouple at room
temperature are responsible for this erroneous indication. From about 150°C on the
display should be correct. The linearization accuracy is achieved at approx. 400°C.
To be able to check the thermocouple with the first commissioning, a nominal value
has to be set in any case, which lies above the current actual value.