Dry ice is the solid form of carbon dioxide (CO2) which has the unusual property of subliming, or changing, directly from a solid to a gas, leaving no residue. At atmospheric pressure it sublimes at -78.7°C providing a cooling effect of 628 kJ/kg.

Clean Surface Blasters accelerate the dry ice pellets to high speed using compressed air available from standard industrial compressors. They offer one of the most advanced and environmentally friendly methods of surface cleaning or decontamination.

The dry ice, although hard in appearance, does not rely on its abrasive properties for effective cleaning. This minimises the risk of damage to the substrate, or the areas adjacent to the workpiece, making Clean Surface Blasters ideal for cleaning delicate substrates such as printed circuit boards, or highly polished moulds. In the latter case, the blasting can often take place with the mould still hot and in-situ.
 

By adjusting the simple pneumatic dry ice flow control on a Clean Surface Blaster, cleaning conditions can be adjusted to ensure removal of only the contaminants from surface coated components, allowing the bond between substrate and coating to remain intact. Alternatively, the cleaning parameters can be set to the optimum level and both contaminant and coating can be removed in one operation.

When the pellets impact on a substrate with a tightly bonded layer of surface contamination, or unwanted coating, the dry ice creates temperature differences between the substrate and the surface layer on a microscopic level.

 
The resulting differential contraction cracks the surface layer and allows the pellets to penetrate. Once between the surface layer and the substrate, the pellets complete their sublimation creating a large volume of CO2 gas which rapidly expands and simply blasts the surface layer away from the substrate into the airstream.

Because the dry ice sublimes during the cleaning process, there are no problems associated with disposal of the blasting medium. Compared to solvent cleaning, there are no toxic fumes, and no hazardous liquid waste is created.