Thermal Spray

Thermal Spray Coating Process

Powder Feedstock -> Powder Particle Melting (Gas or Electric Heating) -> Molten Particle Acceleration -> Particle / Substrate Impact -> Coating

Processes Involving Thermal Spray

The thermal spray processes involve such heat that the process produces a very fine dust (fume), typically sub-micron in size and very uniform. Some of the materials used in thermal spray applications have associated adverse health effects, and defined minimum exposure limits set for them, which necessitates effective dust collection.

Following are terms for typical thermal spray processes that produce fumes needing to be controlled:

• Flame Spray                   Powder Flame Spray    
• Wire Flame Spray          High Velocity Oxy / Fuel Spraying (HVOF)  
• Cold Spray                      Plasma Arc Spray
• Electric Arc Spray

Related Processes Producing Contaminants—Surface Preparation and Finishing Operations:

• Abrasive blasting
• Grinding
• Wet machining

Special Considerations

Many metal fume dusts are combustible and those operations generating or handling metal fumes can require special mitigation efforts to minimize fire and explosion risks. Standards such as NFPA 654 can provide guidance for those who generate and handle these types of dusts. See the Donaldson Dust Collectors and Combustible Dust Strategies brochure.

Metal fume dusts may also have identified adverse health impacts, and special mitigation strategies may be required to limit occupational exposure below levels OSHA or other health organizations have established for these materials.

Collectors In Use