Beyond the Blast: What is Shot Blasting?

In this edition of Beyond the Blast, we move from shot peening to exploring another in-demand surface treatment: shot blasting. Also known as blast cleaning, shot blasting delivers an efficient and cost-effective way to clean and prepare surfaces. We’ll examine the fundamentals of shot blasting and its various applications.

Q: What is Shot Blasting?

Shot blasting is a surface preparation technique used to clean or prepare the surface of a material by propelling abrasive materials at high speeds onto the surface. Unlike shot peening, which aims to induce compressive stresses, shot blasting is primarily used for cleaning and preparing surfaces for further treatment, such as painting, coating, bonding, or texturing.

In shot blasting, abrasive materials such as steel shots, grits, cut wire, or other abrasive particles are propelled at the surface of the material being treated using compressed air or centrifugal force.

Q: What are the benefits?

The high-velocity impact of these abrasive materials or particles removes contaminants like rust, scale, paint, or other surface imperfections, leaving behind a clean and roughened surface ready for the next stage of processing. The removal of these contaminants is known as “cleaning.”

Shot Blasting is an efficient and cost-effective method for cleaning and preparing surfaces for coating and adhesion.

Q: What industries use Shot Blasting?

Shot blasting is often utilized in higher-volume applications in the following industries: aerospace, automotive, coating, construction, die casting, foundry, heat treating, metal fabrication, and shipbuilding.

Within these industries, the applications vary in the difficulty and amount of contaminant that must be cleaned. For example, you could have a foundry application where shot blasting machines are used for core knock-out that requires the abrasive particles to penetrate the initial sand mold prior to impacting the cast product. Other applications include utilizing the shot blasting process for surface preparation on a complete fabrication before coating.

Q: What is the difference between Shot Blasting and Sandblasting?

Shot blasting and sandblasting are both surface preparation techniques used to clean or modify the surface of materials, but they use different abrasive materials and techniques.

Abrasive Material

Shot Blasting – In shot blasting, abrasive materials such as steel shots, grits, or other metallic particles are propelled at high speeds onto the surface of the material being processed. These abrasive particles are typically hard and spherical in shape.

Sandblasting – Sandblasting typically uses non-metallic abrasive material such as garnet, aluminum oxide, or glass beads. Sandblasting involves propelling the abrasive material using compressed air.

Abrasive Impact

Shot Blasting – The abrasive particles used in shot blasting impact the surface of the material being processed at high velocities, creating a mechanical cleaning or surface strengthening effect. Shot blasting is often used for cleaning, deburring, descaling, and surface preparation.

Sandblasting – Sandblasting also relies on high-velocity impact to clean or modify the material’s surface. However, sandblasting creates a more aggressive surface profile than shot blasting, making it suitable for applications where a rougher surface texture is desired.

Applications

Shot Blasting – Shot blasting is commonly used in industries such as automotive, aerospace, metal fabrication, and construction for cleaning and preparing surfaces for further treatment or coating. It is cost-effective and typically utilized in high-volume applications.

Sandblasting – Sandblasting is widely used in various applications, including paint removal, rust removal, surface texturing, and engraving. It is commonly used in industries such as shipbuilding, restoration, and monument cleaning. It is best suited for lower-volume applications where cost is not a mitigating factor.

While shot blasting and sandblasting are effective surface preparation methods, factors such as the desired surface finish, the material being treated, environmental considerations, and specific application requirements will determine which surface preparation method is best for you. Our Bronco team is happy to answer any questions you may have.