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Installation of the Crucibles
Use only standard supports. Between crucible and support should
be separating material: paper, coke, alumina.
Around of an upper crucible edge it is necessary to create an even
gap. For this purpose it is possible to use cardboard or arboreal
chips. It is not allowed to use wedges made of fire proof material.
The burner axis should be in a bottom plane of a crucible.
A gap between crucible and a furnace cover should be insulated
by thermoinsulating material.
The burner should be established so that the flame does not flap
directly in a crucible and bent it on tangent.
For installation and extraction of crucibles tongs (claws) should be
used. Tongs should correspond to the shape of crucible and be
wrapped up with mild material.
In resistance ovens and induction furnaces air gap
between crucible's edge and oven's cover should
be sealed up by mixture on the ground of fireproof clay.
In induction furnaces space between crucible
and inductor is filled by insulating material.
Loading of Metal
The metal is necessary to load in the previously warmed-over
crucible. The metal should be dry and heated a little.
The large pieces should be placed into crucible by grips,
avoiding their impacts with a crucible.
The ingots should be packed into a crucible upright excluding
jamming of separate pieces.