The New Standard in Industrial Dust Collection

High-Efficiency "Plug-and-Play" Dust & Fume Collectors

The Donaldson Torit Downflo® Oval cartridge dust and fume collector now sets the standard for industrial dust collection – by providing a 25% increase in airflow capacity, improved airflow path, and a 29% increase in pulse cleaning pressure. These compact, high-efficiency units use high efficiency oval-shaped cartridge filters, especially well-suited for filtering the sub-micron dust. There are 26 Downflo Oval cartridge dust collectors models including 3 self-contained, “plug and play” units: DFO 1-1, DFO 2-2, and DFO 3-3.

Downflow Oval Dust Collectors

Torit Downflo Oval CollectorA family of over-achievers

The high performance Downflo® Oval (DFO) family of over-achieving dust collectors provides up to 25 percent more filtration capacity than other same-sized cartridge collectors. Powered by proprietary Ultra-Web® nanofiber 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 nanofiber 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.​



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
10-year warranty
Product Literature
Downflow Oval Dust Collectors Brochure

Downflow Oval DFO 1-1, 2-2 and 3-3

Downflow Oval DFO 2-8 to 4-128

Downflow Oval DFO 2-4 and 3-6

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.


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


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.


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 fiber of 0.2-0.3 micron in diameter, Ultra-Web nanofibers form a permanent web-like net with very fine interfiber spaces that trap dust on the surface of the media.

DFO Filter Media Pleats

The innovation of shorter and stiffer filter pleats helps minimize 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.

Downflo Oval Filter (Left) VS Standard Filter (Right)


Unique Oval Shape Contributes to Higher Airflow Capacity

The Downflo Oval filter design is a reflection of Donaldson Torit’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 (Left) VS Standard Collector: 7315 CFM (Right)


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 (Left) - DFP 3-3 Stress and Deflections Model (Right)


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).


DFO 1-1, 2-2, 3-3

Collector DesignStandardOptional
Mild Steel Construction 
Integral High Performance Power Packs 
Ledge-Free Hopper 
Sprinkler Taps 
ExtraLife Filter Cleaning System 
Quick-Removal Access Covers 
Integral Exhaust Silencer 
Airflow Damper 
Stainless Steel Construction 
Explosion Protected Models 
High Static Power Packs 
Inlet Damper 
Abrasion Resistant (AR) Inlet 
Sprinkler Heads 
Extraction Arms (7, 10, 14) 
Caster Packs 
Bag-Out Kit (Filter & Discharge) 
Bag-In/Bag-0ut Kit (Filter & Discharge) 
Cartridge FiltersStandardOptional
Ultra-Web (MERV* 15) 
Ultra-Web SB (MERV* 15); Ultra-Web AS (MERV* 15); Fibra-Web (MERV 14); Ultra-Tek (MERV 12); Thermo-Web (MERV 14); Torit-Tex (MERV 16) 
HEPA/ASHRAE Afterfilters 
Paint SystemStandardOptional
Electrostatically applied powder coat TGIC polyester texture finish (2-mil dry film thickness) inside and out. Paint system passed 350-hr. salt spray test. 
Custom Color 
Hostile Environment Coating 
Epoxy Coating 
Hopper DischargeStandardOptional
10-Gallon Pail Pack 
10-Gallon Pail Pack with Sealer Gear 
25-Gallon Dust Container 
Electrical Controls, Gauges, and EnclosuresStandardOptional
Minihelic** Gauge 
Manual or Automated Downtime Cleaning 
Solenoid Enclosure in NEMA 12 
Continuous On-Demand Delta P Control 
Solenoid Enclosure NEMA 9 
Starter Controls 
10-Year Warranty 

DFO 2-4 Through 4-128

Collector DesignStandardOptional
Mild Steel Construction 
ExtraLife Filter Cleaning System 
Quick-Removal Access Covers 
Ledge-Free Hopper 
Sprinkler Taps 
Stainless Steel Construction 
High Temperature Construction 
Explosion Protected Models 
Direct Drive Fans 
Chamber and Exhaust Silencers 
Abrasion Resistant (AR) Inlet 
Air Management Modules 
Extended Dirty Air Plenum 
Steep-Sided Hopper 
2-Mod Hopper 
Sprinkler Heads 
Service Platform (OSHA compliant) 
Damper Pack 
Drum Sentry Drum-Full Indicator 
Lined Clean Air Plenum 
Bag-Out Kit (Filter & Discharge) 
Bag-In/Bag-0ut Kit (Filter & Discharge) 
Cartridge FiltersStandardOptional
Ultra-Web (MERV* 15) 
Fibra-Web (MERV 14); Ultra-Tek (MERV 12);  
Ultra-Web SB (MERV* 15); Ultra-Web AS (MERV* 15); Fibra-Web (MERV 14); Ultra-Tek (MERV 12); Thermo-Web (MERV 14); Torit-Tex (MERV 16) 
HEPA/ASHRAE Afterfilters 
Paint SystemStandardOptional
Prime Coated Interior 
Textured Multi-Coat Paint Finish with 2,000-Hour Salt Spray Performance 
Custom Color 
Premium Duty Coating 
Epoxy Coating 
Hopper DischargeStandardOptional
Drum Cover and Hose 
Slide Gates 
Rotary Valves and Transitions 
Screw Conveyors 
Electrical Controls, Gauges, and EnclosuresStandardOptional
Control Box w/Timer in NEMA 4 Enclosure 
Magnehelic** Gauge Controls 
Delta P Control, Delta P Plus Control 
Dustronix Control Assembly 
Custom Panels 
Photohelic** Gauge Standard and Weatherproof 
Basic Cold Climate Kit 
Heavy-Duty Cold Climate Kit 
Solenoid Enclosure (NEMA 7 & 9) 
10-Year Warranty 

*The Minimum Efficiency Reporting Value (MERV) of this filter cartridge has been determined through independent laboratory testing using ASHRAE 52.2 (2007) test standards. The MERV rating was determined at a face velocity of 118 feet per minute and loading up to four inches water gauge. Actual efficiency of any filter cartridge will vary according to the specific application parameters. Dust concentration, airflow, particle characteristics, and pulse cleaning methods all affect filtration efficiency.

** Magnehelic and Photohelic are registered trademarks of Dwyer Instruments, Inc.

Ultra-Web Technology Provides Filters that Deliver

Proven and proprietary Ultra-Web® technology delivers longer filter life, cleaner air and greater cost savings.

Downflo Oval (DFO) Dust Collector

This high performance dust collector provides up to 25 percent more filtration capacity than other same-sized cartridge collectors.

Downflo Oval DFO Filter Changeout

The Downflo Oval - DFO - provides easy filter changeouts with its quick-release handle design.