There is no “one-size-fits-all” blasting process. Blasting media, type of blasting equipment, and even added cleaning solvents, chemicals, or compounds all play important roles in the type of finish your parts receive. A combination that works well for one particular job may be completely wrong for another.
No matter what a completed solution becomes, every blasting process is based on one of two basic blasting methods — air blasting or wheel blasting.
Wheel blasting is the process of using centrifugal force to abrade surfaces. Wheel blasting equipment consists of an internal wheel, containing the blast media, and an external wheel, containing the parts being processed. As the internal wheel spins, centrifugal force propels the blast media toward the parts, which spin in the opposite direction in the outer wheel. Wheels are available in different sizes and shapes, and can be spun at varying speeds depending on the needs of the user. Wheel blasting is a high power and high efficiency blasting method. Blasting media is typically stainless steel shot, cut wires, or grit.
Air blasting is the process of using compressed air to propel blast media at the parts that require cleaning. Air blasting is a powerful method that is commonly used to remove rust, corrosion, carbon scale deposits, fungus, and other contaminants from parts before they receive finishing treatments. There are a number of air blasting subtypes, all with unique benefits:
Also known as water blasting, this technique is popular because of its simplicity; only one operator is required. High pressure water streams combined with a blast media are used to remove paint, chemicals, or other buildups without causing any damage to the part surfaces. The water can then be filtered and recycled, reducing waste and minimizing the impact of the process on the surrounding environment.
Pieces of dry ice are propelled by compressed air in this blasting process, which helps to clean parts in two ways. First, the impact of the dry ice against parts removes contaminants, similar to other blasting processes. Second, the dry ice impact causes the blasted parts to cool suddenly, which shrinks them imperceptibly — this shrinking helps to dislodge tough-to-remove contaminants. As an added bonus, the dry ices subliminates from a solid directly to a gas, leaving no residue on the parts.
In this blasting technique, blast abrasives are combined with soap and hot water to remove particles from parts, as well as degrease their surfaces. This process eliminates airborne dust, allowing for the use of silicate blast media, which could otherwise be hazardous. Wet abrasive blasting also allows certain materials, such as asbestos and other poisonous products, to be removed from parts in a decontamination process.
The primary blasting method that you choose will be the cornerstone of your completed blasting solution. It is important to know the differences between the different blasting techniques, as well as their individual strengths and weaknesses, in order to make a well-informed decision.
DeLong Equipment Company’s expert staff has more than 275 years combined experience and can offer guidance and expert advice in all areas of blasting — contact us today to learn more!