Air brake systems have significantly improved the safety of braking systems in modern trucks and trailers. With B double trailers, the combination length of the truck and trailers may be 25 meters with a gross mass of 42.5 tonnes spread across 9 axles. An efficient and well maintained braking system is of vital importance.
The air brake system has many components, all of which must be correctly functioning. The air dryer is one of these important components designed to remove impurities (water and or oil vapours) before they reach the air tanks and valves.
Once air leaves the compressor it passes through the air dryer. The air dryer filter retains the moisture by the contents of the filter.
Moisture condenses out also collects at the base of the dryer.
When the compressor unloads, the water is expelled and dried air flows back through the system drying the filter contents.
In normal operating conditions, with correct brake system maintenance, the filter has a life expectancy of 1-2 years.