Donaldson Endurance™ Air Filters
For heavy duty applications

The nanofiber technology causes submicron contaminants to be held on the surface layer of smaller fibers. This filtration characteristic is only possible with this new type of air filtration technology. In on-highway applications, where the contaminant is primarily submicron in size, Donaldson Endurance filters cause less restriction than conventional filters with cellulose media. The smaller interfiber spaces of nanofiber technology have a higher efficiency and capture more contaminant.

The following illustration may help visualize these phenomena: Imagine two filters, a chain link fence and a mosquito net, with a tennis ball being a dirt particle. As you may have observed, a tennis ball will fit quite nicely into an opening of a chain link fence, but will obstruct the hole almost 100%. Now imaging the same tennis ball covering a mosquito net. The tennis ball, at the point of contact with the netting, will obstruct much less filter area than the chain link fence example. In fact, air will flow around the tennis ball all the way to the point of contact. It will take many more particles to obstruct the netting surface area than the chain link fence.

Donaldson Endurance™ air filters are guaranteed to deliver twice the miles between change intervals over cellulose air filters for on-highway applications or customers receive a new filter at no charge.

Donaldson Endurance™ Air Filters With Nanofiber vs. Conventional Cellulose
Nanofibers have submicron diameters and small interfiber spaces, which result in more contaminant being captured on the surface of the media and lower restriction.	Cellulose fibers are larger than nanofibers, and have larger spaces between the fibers, causing contaminant to be held in the depth of the media and plug the airflow path; resulting in higher restriction and less capacity.
Red circles represent the diameter of a 2 micron and a 5 micron particle.