Service of refractory linings in rotary furnaces used for obtaining silicate melts for stone castings

Conclusions

In the production of stone castings the refractory lining of the rotary furnace is subjected to the action of the acid melt, especially intensely with a melting time of more than 5 h.

The most resistant proved to be a refractory lining made from chrome-magnesite brick. With solution of the lining,the melt is enriched with oxides of chromium which increases its crystallization capacity.

A big effect on the wear of the lining is exerted by the melting time, especially the duration of the homogenizing period. A reduction in the melting time is obtained by using fluorspar in amounts of up to 4% which markedly reduce the rate of wear.

The hatch should be fused with periodic and slow rotation of the furnaces; continuous rotation with a rate of more than 1 rpm gives rise to fast erosion of the lining without greatly affecting the melting time.

Together with the positive influence of the soluble parts of the chromite-magnesite lining, the presence of the insoluble grains of chromite adversely affect the properties of the melts and castings.