The air valves used in the brake system are the
control valve. These valves control the application
brake valves, park brake valves, service brake relay
and release of the service brakes and parking
valves, park brake relay valve, and the spring brake
brakes and are all a part of the crane's air system.
For more detailed information concerning the air valves used in the
crane's brake system refer to Section 7 - AIR SYSTEM.