Sandblasting and waterblasting both stem from naturally occurring processes, with erosion predating human innovation. The preliminary sandblasting process was developed in the 1870s and has since been used for sharpening tools, engraving, cleaning, and weathering surfaces. By the 1970s and 1980s, advancements made waterblasting a safe option.
In recent years, waterblasting has grown in popularity for surface preparation applications. It offers a superior surface profile compared to sandblasting, easier material access, and safer cleaning. Many contractors now prefer waterblasting, but why make the switch?
Surface Profile
Both sandblasting and waterblasting break down coatings and paint. Sandblasting creates a seemingly smooth surface but leaves microscopic peaks that trap contaminants and abrasive particles, reducing the bonding surface for new coatings.
Waterblasting, on the other hand, preserves the original surface profile without trapping particles or contaminants. High-pressure water shears away coatings, resulting in a better bond for subsequent layers.
Material Access
Sandblasting materials can be costly and harmful to health and the environment. Beach, river, and crystalline silica sands, for example, are often prohibited due to health risks, including their classification as a Group 1 carcinogen. Alternative materials like glass beads, steel grit, and copper slag can cost up to $5 per pound, adding significant expenses to projects.
Waterblasting often eliminates material costs. Facilities typically provide water and recycling systems, reducing expenses related to material and waste disposal. Additionally, water suppresses dust, improving safety for operators.
Environmental Trends
Sandblasting materials often contain hazardous substances like silica, aluminum, and copper. Despite mitigation efforts such as blast enclosures and water curtains, sandblasting produces contaminated particles requiring safe disposal, which increases costs and environmental impact.
Waterblasting minimizes airborne contaminants and makes cleanup easier. Contaminated material is captured in water, which can be filtered and reused. This reduces environmental harm and disposal costs.
Considerations for Waterblasting
While waterblasting units are more expensive upfront than sandblasting setups, lower operating costs make them a worthwhile investment. A typical unit includes a trailer, pump, hoses, guns, and nozzles, with some featuring on-board water tanks for consistent supply.
Selecting the right equipment is critical. Pumps with adjustable pressure settings and standardized, color-coded hoses ensure compatibility and safety. Taller structures may benefit from automated systems like magnetic carriers for efficient cleaning.
Conclusion
Waterblasting offers a safer, more environmentally friendly alternative to sandblasting. With increasingly stringent regulations on sandblasting, contractors should consider waterblasting to achieve better surface preparation while reducing costs and environmental impact.
To learn more visit Jetstream of Houston, LLP.
*Images courtesy of Jetstream.
