The refractory ramming mass is composed of a high proportion of granular materials and a low proportion of binder and other components. It should be constructed by strong ramming.
Since ramming mass is mainly used in the areas in direct contact with melt, it is required to have good volume stability, density and corrosion resistance. If it is used in the induction furnace, it should also have good electric insulation properties.
The binder should be proper. Sometimes, binders are not added and some flux are added. The common binders for acidic ramming materials include sodium silicate, ethyl silicate and silicone. Borate is mainly used in the dry rammin mass; magnesium chloride and sulfate salts are mainly used in the alkali ramming mass. In the dry ramming masses, iron flux is added while Glauber's salt is added in the chromite ramming masses.
Compared to other monolithic materials, ramming masses are dry or semi-dry bulk materials. Ramming mass obtains its dense structure by strong ramming. Only when heated to the sintering temperature, the conbination will be strong. When the ramming mass is formed, different heating methods can be chosen to promote its hardening or sintering according to its hardening characteristics.
