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This may cause significant chemical reactions to occurs eventually leading to affect the life
of elements. Operator must remember that SiC elements always prefer to have oxidizing
atmospheres .This is due to the fact that a protective layer of silica glazing is built up to
protect the elements against further oxidation.
Atmosphere
Crusilite
Globar SG
Comments
Air
1575°C
1650°C
Must be dry & clean
Vacuum
1000°C
1100°C -1300°C
Depends on degree and
period of the application
Nitrogen
1250°C
1400°C
Exothermic/
1000°C -1250°C
1250°C -1400°C
Very variable, depends on dew
Endothermic
point and gas composition
Gas
Hydrocarbons
1250°C
1250°C
Periodic burn off required
2.2.3
MoSi Heating Elements
2
Kanthal Super is a unique material combining the best properties of metallic and ceramic
materials. Like metallic materials it has a good heat and electric conductivity and like
ceramics it withstands corrosion and oxidation and has a low thermal expansion. It is not
affected by thermal shock and is strong enough to withstand many years of service as a
heating element. The resistance of Kanthal Super elements does not change due to ageing
even after having been in operation for a long time at high temperatures. Due to these
properties a failed element can easily be replaced without the performance of other
elements connected in series being influenced.
Kanthal Super elements are extremely brittle. In order to minimize the damage
risk during the transportation 1700°C furnaces are sent without their elements
assembled. Please use an experienced technician while installing the elements.
2.3
Refractory Insulation
Labnics employs only modern heat insulating materials which can be defined as fiberboards and
insulating bricks .Modern insulation materials are capable of very efficient heat insulation as well as
giving a very low mass .Still at commissioning these materials emit a disturbing gas which may be
felt at only first heat up. Most of these discharge takes place during tests at manufacturing stage,
even so if any felt during first use, please do not think this to be a problem.
2.4.
Electrical Layout
Labnics employs electrical components fit for CE regulations during production .Furnaces do have
all necessary safety cut off precautions if there need be.
