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OPERATION GUIDELINES OF THE CRUCIBLES


STORAGE 


_Хранение_1.pngThe crucibles should be stored in dry well-aired room, on wood
shelving (supports).
The storage of the crucibles on concrete or
metal floor is not allowed.

It is not allowed to put the crucibles one into another.



TRANSPORTATION


_Транспортировка_1.pngIt is impossible to enable pushes and impacts on the crucibles.
It is impossible tо move the crucibles on a floor edgewise or on
the bottom edge.
It is recommended to use the trolleys with padding for transportation.

PREPARATION OF CRUCIBLES


_Подготовка тиглей_1.png  
Drying of crucibles

- at temperature 200
°C 24 hours at least. The rise of 
temperature should not be sudden at most 30°C per hour.


Glowing of crucibles



- crucibles of type C - rise of temperature till 900°C in 50°C per hour.
- crucibles of type A and K - rise of temperature till 1050°C in 100°C
per hour.

- crucibles of type X - rise of temperature till 400°C in 100°C per hour

and further till 1050°C as soon as possible.


INSTALLATION OF THE CRUCIBLES



_Установка_2.png

The burner axis should be in a bottom plane of a crucible.        


_Установка_3.pngThe burner should be established so that the flame does not flap
directly in a crucible and bent it on tangent.

    

_Установка_4.pngA gap between a crucible and a furnace cover should be insulated
by thermoinsulating material.              

_Установка_5.png

Use only standard supports. 
Between crucible and support should 
be separating material:       
paper, coke, alumina.

_Установка_6.png
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.

_Установка_7.png  

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.


_Установка_8.pngIn 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.

LOADING OF METAL


_Загрузка металл_1.png
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.
 

_Загрузка металл_2.pngThe ingots of metal should be packed into a crucible upright
excluding jamming of separate pieces.

CONDUCTION OF MELTING



_Проведение плавки_1.pngIt is forbidden categorically to warm up a crucible with metal
stiffened in it. The hole for emergency output of molten metal
in furnace should be closed.


_Проведение плавки_2.pngMetal melting is necessary to conduct as soon as possible.

_Проведение плавки_3_а.pngDon't leave empty crucible in the furnace between meltings.
Period between meltings should be minimal

_Проведение плавки_4.pngIt is necessary to change a level of melt in a crucible in order 
to avoid fretting of crucible walls by drosses on a “mirror” of metal.

_Проведение плавки_5.pngKeep strictly to necessary quantity of chemical components for
modification of alloys

_Проведение плавки_6.pngEnter the components only into molten metal.                       

_Проведение плавки_7.pngAfter breaks in work (e.g. stops during weekends) it is necessary
to warm up slowly the empty crucibles in the furnace regardless
of its type.

_Проведение плавки_8.png      In induction furnaces where heating and metal fusion occur at the expense of currents proceeding in it, and the crucible is heated from metal, it is recommended to increase gradually the energy to provide uniform heating of the crucible.
The optimum decision in this case is the continuous operating mode.
                       

CLEANING OF THE CRUCIBLES



_Чистка тиглей.pngAt disconnection of the furnace it is necessary to remove the fluid
melt from crucible.
At the end of melting process the
drosses should be accurately cleaned off from an internal surface
of an hot crucible with the help of the metal scraper or blade

Efficient use of the crucibles means the correct choice of the crucible mark.

This task is quite difficult and solution in mark crucible choice depends on terms of exploitation in each specific situation.