Media blasting involves a compressed air-powered machine that propels various gritty substances (called “media”) at high speed toward surfaces that must be cleaned, etched or primed. There are different media types, each with benefits and applications. Glass bead media, for example, is spherical. When it impacts the surface of a part, tiny dimples consistently form. The resulting finish is bright and looks satin-like.
While soap and water can clean most surfaces, some substances like rust, corrosion or years of built-up gunk require something more intense. That’s where media blasting comes in. This process uses tiny particles fired at high air pressure to remove contamination through abrasion. Blast media can vary from harder materials, such as metal shot or glass beads, to softer ones, such as crushed urea or sodium bicarbonate (baking soda). Using the right blast media for your project is important. Softer abrasives like urea and baking soda can be used at lower blasting pressures, which helps to protect the substrate and reduce damage. This allows for more predictable results and a safer environment.
Both urea and baking soda blasting create very little dust compared to hard silica sand and can be reused for multiple projects. This helps to reduce waste, a major benefit for facilities that may be subject to an air quality permit and impose additional requirements for dust control.
Rust and corrosion are more than unsightly – they can damage industrial equipment and degrade surface integrity. Media blasting like those offered by Airblast AFC Media Blast effectively removes these contaminants, protecting your valuable assets from degradation and costly repairs. Dustless media blasting is also safer for the operators, and it helps keep OSHA compliant by reducing exposure to potentially toxic fumes and dust. This blasting method is also much more efficient than other methods, like chemical stripping or sanding, making it a cost-effective choice for your company. There are many different types of blasting media, each with unique characteristics and uses. Choosing the right one for your project is vital to success; a blaster can help you do that.
Blasting removes surface contaminants like grease, dirt, oil and corrosion to leave a clean, contaminant-free surface to which powder coatings or paint can adhere. The type of media used determines the roughness or smoothness of the resulting finish, and many options exist. For example, grit made from recycled glass and ceramic creates a soft finish, while steel grit produces a coarser texture that works well for stainless steel surfaces. The shape of the abrasive particle also plays an important role. Those with an angular structure, such as silica sand, cut into metal surfaces more aggressively.
Meanwhile, rounded particles, such as crushed glass or plastic beads, peen into characters more like a hammer blow and are gentler on metals. Various options are available, from a biological abrasive, such as ground nut shells and seeds, to a more conventional abrasive, such as aluminum oxide. Another popular option is soda or sodium bicarbonate, which can be used in baking soda blasting and has a low Mohs hardness rating of 2.5, meaning it is much more gentle than traditional abrasives.
Media blasting is an effective way to clean up a surface before applying powder coating. It removes rust, scale, paint and other contaminants, preparing it to apply new material. It can also be used to create texturing or other decorative elements. Wet media blasting processes like soda produce much less airborne dust. In addition, the soda particles are water-soluble, meaning that spent media can be dissolved in water and filtered through a wastewater treatment system rather than built up on soil or populated areas. This reduces your environmental footprint and lowers costs as well. This is especially true when recycling glass beads, typically made from recycled materials.