CDL Air Brake Air Tanks and Drains

Question 1

What is the primary purpose of the safety relief valve on an air tank?

Accepted Answer

To release air if the tank pressure gets too high

Answer

To drain moisture from the tank automatically

Answer

To regulate air flow to the brake chambers

Answer

To equalize pressure between the primary and secondary tanks

Question 2

At what pressure is the safety relief valve on an air tank typically set to open?

Accepted Answer

150 psi

Answer

100 psi

Answer

125 psi

Answer

175 psi

Question 3

How often should air tanks with manual drain valves be drained?

Accepted Answer

At the end of each day of use

Answer

Once a week

Answer

Every 500 miles

Answer

Once a month

Question 4

Which air tank is the first to receive compressed air from the compressor?

Accepted Answer

Supply (wet) tank

Answer

Primary tank

Answer

Secondary tank

Answer

Rear axle tank

Question 5

What is the function of a one-way check valve between air tanks?

Accepted Answer

It prevents air from flowing backward from one tank to another

Answer

It limits maximum pressure in each tank

Answer

It automatically drains water from the tanks

Answer

It controls the rate of air flow to the brakes

Question 6

Why is it important to drain air tanks regularly in an air brake system?

Accepted Answer

To remove water and oil that can cause brake failure or freeze in cold weather

Answer

To increase air pressure in the system

Answer

To reset the governor cut-in pressure

Answer

To allow the compressor to build pressure faster

Question 7

What does a drain cock (drain valve) allow you to do on an air tank?

Accepted Answer

Manually release air pressure from the tank to drain moisture

Answer

Adjust the pressure at which the governor cuts out

Answer

Control air flow to the primary circuit only

Answer

Refill the tank with compressed air from an external source