Coating or painting metal surfaces offers several benefits to a structure. It extends the life of a structure by preventing corrosion and protecting against extreme temperatures, improves the aesthetic quality of the product, and increases the product’s resale value. But coating or painting a metal surface without preparing the surface leads to the coating or paint not properly adhering to the surface, ultimately mitigating its benefits.
While several methods are available, industry professionals agree that using shot-blasting is one of the most effective choices for preparing metal surfaces for future processing. These tips for using shot-blasting in surface preparation will help you make the most of your process.
The Society for Protective Coatings has released standards for coating options, different surface preparation processes, and what standard of cleanliness is necessary for different coatings. Reviewing these standards will aid your operation in determining not only if using shot-blasting in surface preparation is the right choice for your company, but what classification of shot-blasting will best meet the SSPC standards of cleanliness.
Surface preparation involves completely clearing a surface of old paint, mill scale, rust, grease, and oil. While shot-blasting is extremely effective in removing solids from metal surfaces such as rust and old paint, shot-blasting does not remove oils and grease as effectively. For that reason, it may be necessary to utilize an aqueous cleaning system or other degreasing processes before beginning the shot-blasting process.
For those using a blasting room rather than a blasting system, maintaining good room conditions is essential. For instance, the humidity in the room should be kept low when possible because moisture in the air can hinder the application process. Keeping the room well ventilated is also necessary for the safety of the operator and for the finish of the product.
Because workers are applying shot manually in this condition, workers should also be aware of the best methods of applying shot. Shot should not be applied to the same spot for too long for risk of damaging the surface, and walking backward while blasting may also impact the way the shot is applied.
Like all equipment, shot-blasting machinery needs to be regularly maintained in order to work effectively. The dust filtration system should be checked daily. Not only does dust buildup cause a fine film to be left on the products being cleaned, but it can also damage the machine or become a major safety hazard. The interior of the machine as well as the wheels, rollers, and conveyor belts should also be regularly checked for wear.
Viking Blast and Wash Systems can supply all your equipment needs. We are also available to answer questions about how best to keep your shot-blasting machinery running as smoothly as possible for all your metal preparation needs.