Casting
Casting and Carbon Additives: FAQ
Why add carbon to green sand? To create lustrous carbon and a reducing atmosphere that improves surface finish.…
High lustrous-carbon additive for green sand that improves casting finish and replaces sea coal.
Key benefits
- High lustrous carbon yield
- Smoother casting surfaces
- Lower dosage than sea coal
- Low ash, fewer fines
Product overview
Foundry grade gilsonite releases volatile hydrocarbons at pouring temperature that form a lustrous carbon film at the mould–metal interface. Castings come out smoother, shake-out is cleaner and less additive is needed than with traditional sea coal.
Applications
- Grey and ductile iron castings
- Bentonite–carbon blends
- Facing sand
- Non-ferrous castings
Technical data
Data sheet
Foundry Grade Gilsonite
| Property | Typical value | Test method |
|---|---|---|
| Appearance | Black powder | Visual |
| Particle size | 100 – 300 mesh | Sieve |
| Volatile matter | 55 – 75 % | ASTM D3175 |
| Ash content, max | 5 % | ASTM D3174 |
| Moisture, max | 1 % | ASTM D95 |
| Softening point (R&B) | 150 – 200 °C | ASTM D36 |
| Typical dosage | 0.3 – 1.0 % (iron) | |
| Packing | 25 kg bags palletized; 1 MT jumbo bags for blending plants. | |
Typical values. The final specification is confirmed in the COA of each shipment.
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