How does dry ice clean?
The ASCO Dry Ice Blasting machine accelerates with compressed air the dry ice pellets to a speed of approx. 300 m/s (984,25 ft/s). The pellets hit the object to be cleaned. The surface is shock-frozen in a fraction of a second. Due to the sudden thermo shock generated on the surface to be cleaned, the coating/dirt contracts, becomes brittle and cracks. Due to the cracking of the surface, the pellets can reach under the dirt and remove it. The additional kinetic energy removes the coating/dirt from the surface. Immediately after impact, the pellet sublimates and goes back to atmosphere as a pure gas (CO2) without leaving any moisture behind. The only thing left is the coating/dirt removed from the surface and no blasting media has to be disposed of. Since the hardness of the pellets is only approx. 2 Mohs, the cleaning is virtually non-abrasive, and the surface quality is maintained.
The thermo shock
As a result of the sudden and intense temperature shock on the surface, the coating or impurity contracts.
As a result of the contraction the coating cracks and the material becomes brittle due to the cold.
The dry ice pellets hit the surface with great speed and remove the detached coating and clean the surface material.