3 important air compressor safety tips
Do you own or know someone who owns an air compressor? These devices are widely used in many industrial settings and manufacturing facilities, but also can be found in residential homes and small businesses where they are used to inflate car tires and operate air power tools. Each year, Technical Safety BC receives reports of incidents involving air compressors. These are often caused by a lack of regular maintenance and inspection.
Note: The term “air compressor” is typically used to identify the compressor motor and the air receiver tank. However, technically the air compressor is the motor that compresses air, usually mounted on top of a vertical, or horizontal air receiver. The compressor motor requires service and maintenance -- follow the manufacturer's requirements. The air receiver is the pressure vessel that the compressed air is stored in, which is the focus of this article.
Here are some things you need to be aware of if you have an air compressor unit installed in your business or home:
- Drain receiver tank daily – Water is a natural by-product of compressed air. It always forms inside the tank. The condensation that forms inside the tank must be drained regularly to prevent the buildup of condensation. Water left undrained in a pressure vessel can lead to corrosion and possible early failure or, at worst, catastrophic failure from a weakened tank bottom. Owners may want to consider installing a timed auto drain so daily draining happens automatically.
- Inspect regularly – When draining built-up condensation, visually inspect the fluid being drained. Rusty, scaly water is a sure sign of active corrosion. If internal corrosion is suspected, remove the vessel from service, remove a plug or fitting from the tank, and visually inspect the interior shell and head surfaces. The view is limited and a borescope inspection camera may be required. Externally, attachment welds securing the compressor motor and saddle or leg supports should be inspected for any early warning signs of vibration-induced cracking. The tank shell and heads should also be free from any mechanical damage.
- Test pressure relief valves – The pressure relief valve, which protects the air receiver from being over-pressurized, can be compromised by dirt, oil and other contaminants so must be periodically inspected and tested. Each vessel should have a nameplate that details the maximum allowed working pressure (MAWP). Ensure the set pressure of the safety valve does not exceed that allowed on the vessel nameplate and make sure that the capacity of the safety valve is greater than the capacity of the compressor.
Bottom line? Air compressor tanks may look good on the outside, but unseen interior damage can pose serious dangers. If in doubt, replace your unit. When replacing units, always dispose of them properly. Contact your local recycling depot for information.