Shot Blasting 101

Shot blasting is a specialized surface finishing process where small metal (or mineral) pellets, called blast media, are thrown onto the surface of a work piece at incredibly high speeds. With rates of speed ranging from 200-800 feet per second, the impact on the work pieces from this process is what produces the desired surface finishing effect.

Shot blasting can help achieve surface cleaning, surface preparation, descaling, deburring, deflashing, and shot peening.

The process components of a shot blasting system include a shot blast machine, raw and finished work pieces, blast media, dust, and other byproducts. Rosler has more than 80 years of experience in developing comprehensive shot blasting systems.

The two most common types of shot blast machines are turbine blasting and air blasting.

A sampling of shot blasted work pieces
A sampling of shot blasted work pieces.

Turbine Blasting

Turbine blast machines are the most powerful machines on the market, making them ideal for high volumes of mass produced bulk parts or for blasting large, heavy parts. 

The technical principle is based around the use of blasting turbines which are rotating wheels equipped with throwing blades that pick up and throw the blast media at speeds up to 350 feet per second onto the work peice. 

The video below includes an animated depiction of the process.

Examples of turbine blasting equipment include:

Air Blasting

Air blasting leverages the use of compressed air to accelerate the blasting media through nozzles and onto the work piece.  This method is highly versatile and capable of providing very gentle as well as highly aggressive shot blasting. 

Visit our air blast archive for more information.

Wet Blasting

A highly specialized type of air blasting worth noting is wet blasting.

In this process, the blast media is mixed with water to create a blast “slurry” which is then fed through the nozzle using compressed air.  Wet blasting is unique in that it virtually eliminates dust and provides a beautiful matte finish. 

It is ideal for sensitive, delicate parts.

Types of Work Pieces

Shot blasting can be used to finish a huge variety of parts, from small parts weighing only a fraction of an ounce to large parts weighing up to 500,000 lbs (230,000 kg).  Metal is the most common type of work piece, however, shot blasting can also be used on work pieces made out of stone, plastic, or even wood.

Fasteners before and after shot blasting
A fastener before and after shot blasting.

There are too many work pieces to list, but common applications include structural steel, aerospace and automotive components as well as orthopedic implants, gears, pump housings, valve bodies, castings, screws, rivets, and more.

Duroplast automotive parts are an example of shot blasted work pieces.

Blast Media

When blasting comes to mind, many people still think of sand blasting, however, sand has been replaced with a wide variety of metal and mineral blast medias. 

Shot blast media examples.

The four most common types include:

  • Metallic media – Carbon steel, stainless steel, aluminum, zinc.
  • Mineral based media – Aluminum oxide, silicon carbide, glass beads, ceramic beads, garnet.
  • Plastic media – Polyamide, duroplast, acrylic, melamine, urea, nylon.
  • Organic media – Corn cob, walnut shells.

Visit our blast media archive for more information.

The Rosler Way

Whatever your shot blasting needs are, you can count on Rosler to help you find a better way. Contact us today to discuss your unique challenges.

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