Main Air Receiver Safety Features
(a) Four Safety Features and their Purposes:
- Pressure Relief Valve:
- Purpose: This is the primary safety feature and acts as a last line of defense. It automatically releases compressed air if the pressure within the receiver exceeds a predetermined safe limit (typically set pressure + 10%). This prevents the receiver from rupturing due to excessive pressure buildup.
- Safety Relief Valve (Optional):
- Purpose: Provides an additional layer of safety. This valve, typically set at a higher pressure than the pressure relief valve, acts as a backup in case the primary valve malfunctions. It opens automatically to release compressed air if the pressure exceeds its set point, preventing catastrophic failure.
- Drain Valve:
- Purpose: Allows for the removal of accumulated condensate (water) from the bottom of the air receiver. Moisture in the compressed air can cause corrosion and weaken the receiver walls over time. Regularly draining the condensate helps to prevent this and maintain the integrity of the receiver.
- Pressure Gauge:
- Purpose: Provides a visual indication of the air pressure within the receiver. This allows operators to monitor the system pressure and ensure it stays within the safe operating range. It also helps identify potential pressure drops or malfunctions within the compressed air system.
(b) Pressure Relief Valve Lifting Pressure:
The pressure relief valve on a main air receiver should typically be set to lift at a pressure that is 10% higher than the maximum allowable working pressure of the receiver. This provides a safety margin to prevent the receiver from rupturing in case of sudden pressure surges or malfunctions.
Important Note:
The specific pressure settings for safety devices should be based on the manufacturer’s recommendations and relevant safety codes for your region. Never tamper with these settings or bypass safety devices. Regularly inspect and maintain these safety features to ensure they function properly and can protect your compressed air system.