Compressed Air Application: Sandblasting/Abrasive Blasting

Abrasive blasting is a process where various media (depending on the application) is shot against a surface to change its texture. Abrasive blasting may roughen or smooth a surface as well as remove corrosion.  The abrasives in this application are typically propelled by compressed air, so choosing a compressor that will provide sufficient airflow is critical.

Important compressor considerations for this industry:

• Flow is important in this application, even more important than pressure. Typically the blaster will require less than 120psi, which is standard for air compressors.
• Because the air is being used to propel the media, sand blasting applications use more air than many other applications and may require a larger compressor or a compressor that is able to be run with continuous duty.
• Depending on the equipment being used, the CFM may vary from six CFM on a 1/8-inch nozzle to 220 CFM on a 3/8-inch nozzle. (See chart below for sizing and pressure.)
• Many blasters have a listed CFM requirement, but some don’t. If a requirement isn’t specified, then the user will need to use the nozzle sizes as a guide.
• Keep in mind that over time the orifice will wear out and will use more air than originally designed for.

Application requirements to consider:

Do you need oil-free air or is an oil-lubricated compressor acceptable? If you don't care about small amounts of oil in your process, then oil-lubricated is perfectly fine. If oil in your process is an issue, you will also need to consider filtration or an oil-free compressor.

Do you need dry air? Depending on the media used and the orifice, dry air may be critical to continued reliability of the sandblasting system.  Moisture in the air can cause the blast media to clog the orifice or cause sputtering.

Do you need breathing air? Many times, breathing hoods are used in sandblasting booths and it is very important to know that they require Grade D Breathing air, not regular compressed air. Compressed air, even filtered compressed air, is no substitute for proper quality breathing air.

Recommended Products:

• Heavy Duty Piston: Look for a heavy-duty piston, preferably cast-iron for durability and one that is built to withstand continuous use.
• Rotary Screw Compressor: Screw compressors are built to run 100 percent of the time and provide full rated CFM continuously.
• Air treatment: Depending on the media used, very fine dust can be created, which is dangerous for both operator and compressor. Special intake filers should be used to prevent the dust from entering the compressor and causing damage.

Equipment Placement: Ideally, the compressor should be installed away from any dusty environment. Sandblasting can increase the amount of fine particulate in the air and you will want to avoid introducing this dust into the compressor. An extra prefilter on the inlet may be a wise investment to prevent any damage.