Removal of contamination, corrosion or unwanted paint coatings using a substance with a high coefficient of friction causing such cleaning at high speed of contact of its stream with the cleaned surface. Cleaning substances such as special sands, corundum or dry ice are accelerated in special devices powered by compressed air.
This is by far the most significant and important method used for the thorough cleaning of mill-scaled and rusted surfaces is abrasive blast cleaning. This method involves mechanical cleaning by the continuous impact of abrasive particles at high velocities on to the steel surface either in a jet stream of compressed air or by centrifugal impellers. The latter method requires large stationary equipment fitted with radial bladed wheels onto which the abrasive is fed. As the wheels revolve at high speed, the abrasive is thrown onto the steel surface, the force of impact being determined by the size of the wheels and their radial velocity.
