ATCCA501 -REPAIR COMPRESSED AIR BRAKE SYSTEM
Introduction
A compressed air brake system, is a type of friction brake for vehicles in which compressed air pressing on a piston is used to apply the pressure to the brake pad needed to stop the trailers which must be linked into the brake system, such as trucks, buses, trailers, and semi-trailers, in addition to their use in railroad trains. Spring type parking brakes may be installed on an air brake equipped vehicle to ensure a reliable parking brake system. In the service brake system, the brakes are held retracted by springs, and applied by air pressure. Spring type parking brakes are applied and remain applied without air pressure. The parking brake chambers are attached to the service brake chambers and operate the brakes through the same linkage. The system can also act as an emergency brake. Loss of air from the main system may automatically apply the brakes, depending on how the system is piped.