Compressor for Sandblasting & Abrasive Blasting
Various media, depending on the application, are shot against a surface to change the texture in a process known as abrasive blasting. This process may roughen up or smooth out a surface as well as remove corrosion. In this application, the abrasives are propelled by compressed air, so choosing the correct air compressor is an important step. The compressor must have sufficient airflow for the process to operate smoothly.
Important Compressor Considerations for Abrasive Blasting
- Flow is more important than pressure for this application. The blaster will typically require less than 120 psi which is standard for most air compressors.
- Air directly propels the media used in abrasive blasting, therefore, it may use more air than other applications. Additionally, it may require a larger compressor or one that is able to operate continuously.
- Depending on equipment, the cfm my vary from 6 cfm on a 1/8-inch nozzle to 220 cfm on a 3/8-inch nozzle. (See below sizing chart for sizing and pressure.)
- Many blasters have a listed cfm requirement, while others do not list a required cfm as none is directly required. In the case that no cfm is listed, users will need to use the nozzle as a size guide.
- Over time, the orifice on the nozzle will wear and use more air than originally designed.
Application Requirements to Consider
Is oil free air required or is oil-lubrication acceptable? If small amounts of oil in the process is no hindrance, an oil-lubricated compressor is perfectly fine. If oil in the process will affect the final product , an oil free compressor or robust filtration system will be required.
Is dry air required? Depending on the media used and the orifice, dry air may be critical to continued reliability of the abrasive blasting system. Moisture in the air can cause the blast media to clog the orifice and cause sputtering.
Is breathing air required? Abrasive blasting sometimes needs a breathing hood to protect the user. It is important to recognize that Grade D Breathing air is necessary, not simply regularly compressed air. Compressed air, even filtered, is no substitute for proper breathing air.
Equipment Placement: Ideally, the compressor should be installed away from a dusty environment. Abrasive blasting can increase the amount of fine particulate in the air. This should not be introduced into the compressor. An additional pre-filter on the inlet can help prevent damage.
Heavy Duty Piston: Look for a heavy-duty piston designed for continuous use, preferably made from cast-iron to provide durability.
Rotary Screw Compressor: Screw compressors are designed to run at 100 percent duty cycle and provide full rated cfm continuously.
Air Treatment: Depending on the media, it can create very fine dust. This dust is dangerous for both the operator and the compressor. Special intake filters should be employed to prevent dust from entering the compressor and causing damage.