Foundry Dust Collection

Metal casting foundries require dust and fume collection for many processes. Foundry dust collection may involve special challenges, like high temperatures and a heavy dust load. Also, foundries often have both sand and metal dust to deal with.

In the typical foundry process, molds are made of sand or another material. Metal is poured into these molds. After cooling and breaking the mold, the foundry reclaims the sand. Cast parts need to be degated, removing excess pieces of metal from the casting. The parts also require finishing with blasting, grinding, or sanding.

Processes in general foundries that will produce problem dust and fumes include:

• Sand transport and mixing
• Mold production
• Shakeout of cooled parts
• Reclaiming used sand
• Cutting
• Shot blasting
• Grinding or sanding

Each of these foundry dust collection applications creates different requirements. The control of sand in a sand casting foundry is essential, or levels could exceed OSHA exposure limits for silica dust. Shot blasting machines have their own dust collection needs, including separation of dust from the blasting material. Cutting, grinding, and sanding produce metal dust that may contain hazardous materials.

Possible Equipment

• Cyclone
• Chemical isolation system
• Spark trap
• Rhino Drum
• Abort Gate
• Explosion Venting
• Explosion Isolation Valve
• Airlock
• Fume arms
• Hoods
• Downdraft tables

In many foundry dust collection applications, a CMAXX cartridge collector will provide the highest efficiency. The CMAXX is much smaller than a baghouse and handles even very fine metal dust particles. In some applications, such as high temperatures, a BRF baghouse may be considered. In most circumstances, the CMAXX will be recommended.

Depending upon the type of metal used, foundry metal dust may be combustible. For example, dust from an aluminum foundry will be much more combustible than dust from a cast iron foundry. System designers will recommend a dust test. This allows the system to be equipped with OSHA and NFPA approved safety features.