North American Refractories Company

Daniel F Fura

Regis M Perich

H David Prior, Jr

Harold D Prior, Jr

A method of making a cristobalite-free, mullite grain capable of withstanding reaction with molten aluminum, comprising the steps of: producing a clay slurry comprised of water and kaolin clay of a specific particle size; mixing a water insoluble barium or strontium containing compound into the clay slurry in an amount wherein the barium or strontium containing compound content of the slurry is equal to about 8% by weight of the kaolin clay in the slurry; removing sufficient water from the slurry to form a material having an pelletizable consistency; forming the material into pellets; heating the pellets by continuously moving them through a furnace having a zone, wherein the material is exposed to temperatures of at least 2,650&deg; F. (1,455&deg; C.) for at least 30 minutes.

Cristobalite-free mullite grain having reduced reactivity to molten aluminum and method of producing the same

The present invention is directed to an insulating coating for refractory articles, adapted to be applied by spraying or gunning, which is easy to apply, cost effective, eliminates the potential health hazards associated with ceramic fiber paper, and which imparts sufficient insulating properties to the refractory article in high temperature environments. More particularly, the present invention is directed to an insulating coating and a method of preparing the insulating coating wherein the coating composition is comprised of about 25% to about 75% by weight of lightweight aggregate, up to about 25% to about 75% by weight of binder, up to 0.5% by weight of organic fiber, up to about 15% by weight of an additive to improve green strength, and up to about 5% by weight of a foaming agent.

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State College, PA, United States of America

Daniel F Fura