Abrasive Injected Water Blasting

A Primary Mission of the Advisory Council is to promote effective means of surface preparation in the maintenance industry using water and water/abrasive blasting techniques.

The Abrasive Injected Water Blasting (AIWB) process involves introducing an abrasive into a high pressure water stream where it is delivered to the surface to be blasted.

AIWB will impart a profile on the substrate and is capable of cleaning to an SSPC-SP-5, though flash rusting may occur.

This equipment is useful in spot repair requirements for highway structures where localized corrosion and/or damaged paint areas require repair.

While performing the spot repair requirements, AIWB is also capable of feathering transition areas of intact paint, which surround areas prepared to bare metal.

In addition, the surrounding areas of intact paint are sweep-blast to remove delaminated coating.

The observed structures were part of a multiple bridge maintenance painting contract for Virginia Department of Transportation’s Northern Virginia District.

Due to the nature of this repair work, (i.e. spot prepare corroded areas, and overcoat), production rates during a given shift were dependant upon the amount of old coating that was removed.

The water consumed per square foot was also dependent on the amount of coating deterioration on the structure, shown in Table 1.2.

During this eight hour demonstration shift the contractor utilized two Carolina Equipment & Supply Aqua Miser D-44 AIWB units with one blaster per unit to remove all coatings down to bare metal.

This cost model calculated cost for maintenance painting of structures with varying extents of coating deterioration for a comparison between abrasive injected water blasting and hand/power tool cleaning surface preparation methods.