VERDER CARBOLITE GERO RHF 15/15, Инструкции по установке, эксплуатации и обслуживанию

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Materials such as case hardening compounds and other reactive salts may penetrate
the furnace chamber lining and attack the wire elements, causing premature failure.
Use of a hearth tile may be advisable: please consult the Carbolite Gero technical
department.
4.3 Use of Probes and Metal Sheathed Thermocouples
Any metal object used to probe into the product chamber while the
product is connected to the electrical supply must be earthed. This
applies in particular to metal sheathed thermocouples, where the
sheaths must be earthed. The refractory material of the chamber
lining becomes partly conductive at high temperatures and the
electric potential inside the chamber can be at any value between
zero and the supply voltage. Unearthed probes can cause serious
electric shock.
4.4 Atmospheres
When an optional gas inlet is fitted, there is a label near the inlet saying "INERT GAS
ONLY". In practice, inert or oxidising gases may be used, but not combustible or toxic
gases.
The chamber is not gas tight, the gas usage may be high and the chamber is always
likely to contain some air. Residual oxygen of approximately 1% to 2% is to be
expected.
4.5 Heating Elements
If SiC heating elements are used close to their maximum operation temperature of
1600 °C it is possible for bubbles of silica to form on the surface of the elements. The
size of the bubbles can vary. This is an indication that the elements temperature has
exceeded 1625 °C. The silica bubble can be removed, if they are a nuisance to the
application, by careful use of a vacuum cleaner with an appropriate exhaust filter. To
reduce the likelihood of silica bubbles forming, heat the furnace using a reduced
heating rate and if possible use a lower setpoint.
4.6 Silicon Carbide Protection Tiles Option
This product is available with optional heating element protection tiles. When this
option is specified, silicon carbide (SiC) tiles are added to the insulation assembly,
positioned on both sides of the chamber to create a barrier between the working
chamber and the heating elements. This will protect the heating elements from
potentially harmful contaminants that might be placed in the chamber.
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