Dry compressed air for commercial blasting (sandblasting) and coatings plays an important role in the maintenance and preservation of critical public and private infrastructures, such as highway overpasses, bridges, water towers, storage tanks, ships, and pipelines. The steel surfaces of these assets routinely need to be cleaned and coated to prevent corrosion and loss of useful life.
Compressed air is an essential utility in both the surface preparation and coating of steel infrastructure. Compressed air transports abrasive grit that blasts away surface corrosion and old coatings. It’s also used to spray new coatings onto steel surfaces. Clean and dry compressed air is essential in both blasting and coating processes. Contaminants in compressed air, especially water, decrease both contractor productivity and the quality of surface preparation and the adhesion of coatings.
Van Air Systems produces a range of air dryers, filters, and desiccants that are uniquely suited to the needs of commercial coatings contractors. Van Air Systems produces both stationary and portable air drying equipment whose technology is uniquely suited to the blasting and coating industry.
Moisture in compressed air negatively affects both the productivity and workmanship of abrasive blasting contractors. The harmful effects of wet air include the clumping or clogging of abrasive grit, inconsistent and/or excessive flow of abrasive, corrosion of ferrous abrasives, and damage to blast machine valves and controls.
Water in compressed air lines causes paint and coatings to drip, bubble, and “fish-eye”. Wet compressed air may also dilute the paint, both increasing the cure time and affecting the adhesion of the coating to the steel surface. Properly cooling, drying, and filtering compressed air eliminates re-work and increases the quality of the paint job.
Abrasive blasting exposes a steel substrate to atmospheric humidity, and blasting contractors must contend with “flash rusting”. Flash rusting is surface corrosion that appears on steel when it’s not coated quickly enough. The presence of liquid water in compressed air exacerbates a contractor’s problems with flash rusting.
Abrasive blast cabinets and booths are used to clean metal parts in a variety of industrial settings. Compressed air propels an abrasive media against the metal part, removing old paint, corrosion, scale, and other build-ups. Certain abrasives types are highly sensitive to moisture in the compressed air, especially steel grit and soda.