How does air dryer filtration work?
The HGV air braking system is a sophisticated piece of engineering, creating crucial stopping power, and improving safety with evenly distributed braking for rigid and articulated vehicles. That system relies on air dryer filtration to achieve peak performance. Mann+Hummel offers a blow-by-blow account of how it works.
As components go the air dryer cartridge filter plays a vitally important safety role in a commercial vehicle’s air system, removing oil particles and cleaning the air. This filtration device improves the efficiency and reliability of air brake systems by reducing the amount of maintenance needed to clean air brake valves and protects the entire air operated braking system from corrosion and premature breakdown and failure.
The main tasks of an air dryer filtration cartridge are to:
- remove the moisture from the compressed air
- separate larger oil droplets, liquids, and dirt particles
The absorbent material within the cartridge removes oil from the air purge and then recycles it. In addition to removing oil, it also provides better oil assimilation by containing the hydrophobic molecules.
Previously, before the introduction of air dryer filtration cartridges, commercial vehicles required frequent, time consuming and costly draining of accumulated water from their air tanks. Fortunately, modern air dryers absorb water and reduce its effect on the system’s components. This allows the air dryer filtration cartridges to effectively protect heavy-duty trucks and trailers which rely on compressed air for actuation of braking systems and control brake operation.
The principal operation of an air dryer filtration cartridge is based on a simple charge cycle. Compressed air enters the system and passes the pre-filter.
- the air is dried in the desiccant container by means of adsorption.
- the dry air leaves the cartridge through the centre orifice to supply the pneumatic system.
The regeneration cycle
First step:
- the purge valve installed in the air dryer opens and releases the compressed air inside the cartridge to atmosphere. The cartridge is now pressure-less.
Second step:
- dried and expanded air from the pressure reservoir enters the cartridge in the reverse direction.
- the high volume of dry air regenerates the moisture laden desiccant and leaves the cartridge through the thread plate orifice holes.
At this point the whole process continues on repeat until the time where the service interval requires a change in the air dryer filtration cartridge.
Regular and correct maintenance of the air dryer filtration cartridge protects the entire braking system from costly and unnecessary breakdown and repairs but primarily ensures the truck and trailer braking systems operate to their prime efficiency. Always make sure that OE-quality air dryer filtration cartridges are used, such as our MANN-FILTER portfolio of air dryer filtration cartridges that offer industry leading protection for increased service and maintenance schedules and heavy-duty operating cycles.
Components of an air-dryer filtration cartridge
