Air Tanks and Drains Flashcards
7 cards from real CDL AIR BRAKE practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Air Tanks and Drains flashcards as text
What is the primary purpose of the safety relief valve on an air tank?
Answer: To release air if the tank pressure gets too high
The safety relief valve is designed to open and release air if tank pressure exceeds a safe level, protecting the system from over-pressurization.
At what pressure is the safety relief valve on an air tank typically set to open?
Answer: 150 psi
The safety relief valve is set to open at 150 psi to prevent the air tank from being over-pressurized beyond safe limits.
How often should air tanks with manual drain valves be drained?
Answer: At the end of each day of use
Air tanks should be drained at the end of each day of use to remove accumulated water and oil before they can cause problems.
Which air tank is the first to receive compressed air from the compressor?
Answer: Supply (wet) tank
The supply tank, also called the wet tank, is the first tank air enters after leaving the compressor, where it loses much of its moisture.
What is the function of a one-way check valve between air tanks?
Answer: It prevents air from flowing backward from one tank to another
A one-way check valve allows air to flow in only one direction, preventing air from flowing back from one tank to another if a line fails.
Why is it important to drain air tanks regularly in an air brake system?
Answer: To remove water and oil that can cause brake failure or freeze in cold weather
Water and oil accumulate in air tanks and can lead to brake failure, rust, and freezing in cold temperatures if not drained regularly.
What does a drain cock (drain valve) allow you to do on an air tank?
Answer: Manually release air pressure from the tank to drain moisture
A drain cock is a manual valve at the bottom of each air tank that lets the driver release air pressure to drain out accumulated water and oil.
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