Mould and Core Coatings Containing Gilsonite

Refractory coatings protect mould and core surfaces from molten metal. Fine gilsonite can enhance their performance.

Function

Micronized gilsonite in the coating produces a reducing atmosphere and lustrous carbon at the coating surface.

Formulation

• Refractory filler (zircon, graphite, alumina silicate)
• Binder and suspension agent
• Carrier (water or alcohol)
• Small amount of micronized gilsonite

Benefits

Smoother surfaces, easier cleaning and reduced veining in some cases.

Typical uses of coatings

• Cores in heavy iron castings
• Areas prone to penetration
• Large moulds in no-bake systems

Dosage in coatings

Micronized gilsonite is usually added at low levels, typically a few percent of the solids. Higher levels can affect coating rheology and drying.

Application

Apply by dipping, brushing or spraying, then dry thoroughly before closing the mould.

Use micronized gilsonite. See gilsonite in core sand.