How to use the graphite crucible in a right is important.
The first time to use it,we should heat the crucible under a 1300~1500 centigrade,and after 2~3 times,the surface of the crucible could form a sinter layer,so the service life will be longer. If we use it without the sinter layer for the first time, and melting the fusible metal,such as tin,vanadium,aluminum etc,the crucible will be broken quickly,and the graphite will be fire when it reach 700 centigrade.
The crucible should be put onto the special base,and the Dia of the base should be the same as the crucible. And there should be some graphite powder and coal powder on the base. And the material of the base should also be graphite material,it doesn’t allow to put the crucible onto other material base.
It must be very careful to fill in the crucible,and it doesn’t allow to throw the metal into the crucible. And the crucible should not be very full of the metal, coz the metal will expand during the melting process,and the metal material should not be too close to each other.
During the melting process,it should not put the metal in times.
It doesn’t allow to put the crucible into the high-temperature furnace,coz the crucible will crack because of this,and before putting the metal into crucible,the metal must be baked to dry. The wet metal should not be put into the crucible. The temperature of the heating should be heating-up slowly,it’s better to make the same graphite cover on the crucible ,coz it can reduce the losing of the metal.
The crucible should not be put onto the furnace for a long time,coz it can reduce the service of the crucible.the pliers which used for the crucible should be the circle shape.