Bendix oil-coalescing air treatment technology increasingly important to fleets

PuraGuard air dryer cartridges help prevent oil damage to critical vehicle systems.


One of the features that sets the Bendix PuraGuard solution above the competition is the placement of the oil-coalescing material. Bendix places the material before the desiccant, ensuring that oil and oil aerosols are removed before they reach the important moisture-removing desiccant. Competitive designs filter oil after it passes through the desiccant, which contaminates the desiccant and diminishes its ability to remove moisture. In competitive designs, oil reaches the desiccant in both the charge cycle and again in the purge cycle, which pushes the oil back through the desiccant, further contaminating it and reducing its useful life. The Bendix design removes more oil, improving performance and potentially prolonging the life of the filter.

Another distinguishing feature of the Bendixspin-on cartridge design for Bendix PuraGuard oil-coalescing air dryers resides in a patented check valve. Coalescing filters are more efficient when air flows only in one direction through the coalescing media. The Bendixpatented check valve enables this one-way flow and makes Bendix oil-coalescing technology even more efficient than the available competitor's design.

Of course, ensuring effective performance of an air dryer over time means replacing air dryer filters on a regular basis. For better air dryer performance, non-oil-coalescing cartridges can be upgraded to the BendixPuraGuardoil-coalescing cartridge. If the Bendix PuraGuard oil-coalescing cartridge is an OEM standard, it must be replaced with a like unit. When replacing cartridges, fleets need to beware of low-cost and counterfeit cartridges, which are not as effective as original OEM equipment. To ensure fleet owners and operators are using genuine parts, Bendix PuraGuard cartridges feature an embossed silver medallion on the top, as well as the PuraGuard logo on the side.

Preventive Maintenance – As Easy as 1-2-3

Adhering to a strict preventive maintenance schedule is crucial to keeping a vehicle's air system clean and ensuring superior performance. Depending on vocation, Bendix recommends a one-, two-, or three-year air dryer cartridge replacement on vehicles equipped with a Bendix compressor. For severe service applications, such as residential refuse trucks or school buses, the air dryer cartridge should be replaced every year or 100,000 miles; for pick up and delivery operations, or for double- and triple-trailer line haul trucks, every two years or 200,000 miles is recommended. Line haul operations using a single trailer should swap the filter out every three years or 300,000 miles. Recommended intervals for trucks equipped with non-Bendix compressors are six months (50,000 miles), one year (100,000 miles), and two years (200,000 miles), respectively. 

More frequent intervals may be required depending on a vehicle's age, its compressor condition, the operating environment, the vehicle's vocation, and its usage. In conjunction with the guidelines, fleets can determine the functionality of their filters by checking for moisture in the air brake system monthly. If moisture is present, the air dryer cartridge may require replacement.

"In addition to the guidelines for maintenance noted, fleets who acquire used trucks should change the air dryer cartridge as part of their prep work to bring the truck into operation," noted Fred Andersky, director of marketing – Charging. "Changing the cartridge and sticking to a maintenance schedule, like our 1-2-3 approach, helps ensure long life and improved reliability of the air system, critical components, and the truck itself. Bottom line, the right air dryer and cartridge can help a fleet and owner-operator lower their operating costs."

BendixPuraGuardoil-coalescing cartridges are now available for Bendix's AD-9, AD-IS, AD-IP, and AD-SPair dryers, as well as for many competitive air dryers.

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