Abrasive blasting is a process that removes soils, discoloration, and coatings from metal, concrete, or masonry surfaces. It can also be used to add texture to a surface so that new coatings adhere more strongly. Abrasive blasting involves directing a pressurized stream of abrasive material against the surface until the desired effect is achieved. Silica sand has traditionally been one of the most commonly used blasting media. However, when silica sand impacts the blasted surface at high speeds, the grains of sand fracture and create copious dust and respirable crystalline silica. Using an alternative blasting medium can help reduce worker exposure to silica and other hazardous substances.
There are a wide variety of blasting media that can be used in place of silica sand. These may include coal slag, steel shot, glass, grit, walnut shells, and garnet. However, even though these materials do not contain silica, there can be crystalline silica in the base material being blasted. When impacted by the blasting media, the crystalline silica in the base material can become airborne. Milder blasting media like dry ice, baking soda, sponges, and water jets are silica-free and designed to minimize the dust created when the blasting medium strikes the surface of interest.
Sponge blasting involves shooting small pieces of specially made grit sponge at the surface of interest. As the pieces of sponge strike the surface, they adhere to and remove the top layer. Sponge blasting creates very little airborne dust, and the sponge pieces can often be reused. It also reduces the likelihood of ricochet.
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Fully integrated, mobile system
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Dry ice blasting can be used to clean the surface of materials that conduct heat or cold, like steel or other metals. Dry ice blasting shoots pellets of frozen carbon dioxide at the surface of interest, and the combined effect of the collision and the temperature change knocks the coating free. Dry ice is not reusable, as it evaporates as soon as it hits the surface, but it leaves no residue. It is minimally abrasive and effective for restoration projects. However, it should only be used in well-ventilated areas because the evaporated carbon dioxide can displace oxygen.
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Does not include compressed air source
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Soda blasting is a gentle abrasive blasting method that uses sodium bicarbonate (baking soda) as the blasting medium. It is ideal for soft materials like wood and can also be used in restoration projects. It usually requires a much lower blasting pressure. Although the baking soda can’t be reused, it is non-toxic and biodegradable, and creates a much lower volume of waste than traditional sandblasting.
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Fully integrated and mobile
Price: $42,500 (verified 5/7/19)