Downflo Oval (DFO) Dust Collectors

A family of high achievers
The high performance Downflo® Oval (DFO) family of high performing dust collectors provides up to 25 percent more filtration capacity than other same-sized cartridge collectors. Powered by proprietary Ultra-Web® nanofibre filtration technology, DFO delivers cleaner air, up to two times longer filter life, and greater cost savings.

The DFO advantage is found in the collector’s proprietary design and components. The combination of a new cabinet design that greatly lowers cabinet velocities, proprietary ExtraLife™ cleaning technology, and proven Ultra-Web nanofibre filters allows more airflow through the collector without increasing the size of the footprint or damaging the filters.

A smaller collector helps lower the initial purchase price, reduces filter replacement costs and opens up valuable manufacturing floor space.

DFO Offers:

• Lower initial cost per cubic foot of air per minute (cfm)
• Higher efficiency—cleaner air
• Lower pressure drop—greater energy savings
• Fewer filter changeouts
• Reduced filter disposal cost
• Easy system setup
• Less maintenance

Outperforms all other collectors

DFO collectors offer some strong benefits that distinguish them from all other collectors available in the market today.

Easy to use Quick-release handles provide easy cover removal and faster filter access.

Compact Smaller footprints for applications that require maximum cleaning efficiency in even smaller spaces.

Powerful DFO collectors provide 25 percent more capacity than same-sized dust collectors.

Cost Effective The proprietary ExtraLife Filter Cleaning System averages up to 30 percent increase in pulse cleaning energy for unmatched cleaning ability.

Innovative Unique oval-shaped Ultra-Web cartridge filters provide the longest filter life and highest filtration efficiency—which lowers cost. 

Proprietary Technology That Performs

The remarkable story of DFO begins with the oval cartridge and Ultra-Web Media Technology. Proven and proprietary Ultra-Web technology delivers longer filter life, cleaner air and greater cost savings than other types of cartridge filter media. Made with an electrospinning process that produces a very fine, continuous fibre of 0.2-0.3 micron in diameter, Ultra-Web nanofibres form a permanent web-like net with very fine interfibre spaces that trap dust on the surface of the media. 

DFO FIlter Media Pleats

The innovation of shorter and stiffer filter pleats helps minimise dust entrapment and simplify filter cleaning. By reducing the height of the filter pleats from the standard 2 inches to 1.5 inches, the pleat wall is less likely to collapse or bend, which can encapsulate dust and prevent its expulsion.

Standard Filter


Downflo Oval Filter


Unique oval shape contributes to higher airflow capacity

The Downflo Oval filter design is a reflection of Donaldson’s commitment to technical research and development. High performance oval-shaped filters handle up to 25 percent more airflow without increasing velocities, which can cause filter abrasion. Sophisticated FLUENT®*Airflow Modeling Software revealed that oval-shaped cartridge filters have fewer areas of high velocity, resulting in a lower potential for media abrasion and increased filter life.

Downflo Oval Collector: 9145 CFM


Standard Collector: 7315 CFM


Airflow Breakthroughs lead to higher filtration efficiency

Sophisticated computer modeling for fluid dynamics, structural mechanics and acoustics puts DFO models 1-1, 2-2, and 3-3 in a technical class all their own. The illustration below (left) shows how FLUENT Flow Modeling Software enhanced the uniform air velocity distribution through model DFO 3-3. ANSYS®* Structure Analysis Software shown below (right) demonstrates lowest stress levels and deflections for model DFO 3-3 under typical operating pressures.

DFO 3-3 Air Velocity Distribution


DFO 3-3 Stress and Deflections Model


Convex Side Walls 

Technical discoveries improve filtration performance and prolonged filter life. A new cabinet design with convex side walls streamlines the airflow path and increases the cabinet’s cross-sectional area. The convex side walls provide more space between filters, lower cabinet velocities and reduce the potential for media abrasion.


Pulse Cleaning Technology 

ExtraLife Filter Cleaning System uses proprietary, computer-modeled pulse cleaning technology to easily “pulse off” dust from the surface of the filter, improving filtration efficiency and prolonging filter life. The red lines in the illustration show the increased pressure at the front of the Downflo filter generated by the ExtraLife system. The blue line shows the pulse signature of a standard cartridge collector.

Pulse gradients produced by the standard Downflo during pulse cleaning compared to gradients produced by a Downflo with the ExtraLife Cleaning System (red).