The foundry industry Perlite in the ore form is used in high temperature application in the steel, ferrous and non-ferrous industries, as a slag coagulation agent, in ladle topping compounds, as an ingredient in exothermic and insulating sleeves and as a cushioning agent in moulding and core sand.
Perlite ore is also added to foundry and moulding sand mixture as a cushioning agent to compensate for the expansion of silica as it goes through phase transformation or temperature in excess of 600 deg. C. Perlite being volume stable upto its fusion point will absorb the growth of the silica grain.
Produces cleaner metal.
Coagulates slag and traps all impurities.
Simplifies ladle skimming and removal of slag without raking.
Reaction with melt produces no smoke or fume of health hazards.
Additional benefit of sulphur and phosphorous reduction.