1-7. LOCATION AND DESCRIPTION OF MAJOR COMPONENTS (Cont).
AIR/HYDRAULIC BRAKE SYSTEM
Service Air Line
Receives compressed air from towing vehicle for braking purposes
during towing operation.
Directly controls the service brakes. Receives air from service air line
which causes relay valve to release compressed air from air reservoir.
Receives air from air reservoir and actuates master cylinder.
Provides hydraulic pressure to move wheel cylinders in wheel brake
Provide access hole for filling master cylinder with brake fluid.
Receives brake fluid from master cylinder and applies pressure to
brake linings. Fitted with a bleeder valve at rear of cylinder to permit air
to be bled from the system.
Stores compressed air to apply semitrailer chassis brakes. Equipped
with a draincock for draining moisture and releasing air pressure if
brakes are locked.
Prevent moisture and foreign material from passing through air
system. Contain removable elements. Pipe plug at bottom of air filter
may be removed to drain moisture.
Emergency Air Line
Receives compressed air from towing vehicle to engage emergency
Connect emergency and service air lines of semitrailer to towing