Donaldson Torit DRYFLO Mist Collectors

The Donaldson Torit DRYFLO® mist collector is a low profile, machine-mountable, high-efficiency mist filtration solution for wet machining with oil-based, synthetic, semi-synthetic, and water-soluble coolants. DRYFLO cartridge filters contain three stages of high efficiency filtration and are easy to change when maintenance is needed. 

DRYFLO Mist Collectors

290_Dryflow_MistDryflo® mist collectors from Donaldson® Torit® are effective and efficient mist filtration solutions, providing a more productive work environment by reducing coolant and machining oil mists in a machine-mountable package. The Dryflo provides high performance technology and easy, predictable maintenance.

High performance three-stage filtration improves collection efficiency at every stage.
Provides a cleaner work environment for maximum productivity.
Reduces risk of mist related hazards.DryfloMMCMMBEasyChangeout_290
Quick and easy filter changes—workers have minimal contact with collected oil.
Predictable maintenance with a differential pressure gauge.
Lower plant maintenance costs.
Mounts directly onto a machining center to collect oil, water-soluble, semi-synthetic and synthetic coolant.
Low profile.
10-year warranty.
Product Literature
Dryflo® Mist Collectors Datasheet
Dryflo DMC-MMA and DMC-MMB

Normal Operation


DRYFLO Filter Media

DryfloMMCMMBFilterMedia_290Dryflo filter media is made from proprietary synthetic media incorporating both small and large fibers for optimum filtration. The smaller fibers provide increased filtration efficiency; after mist is captured and coalesced, the larger fibers allow the oil to drain from the filter. The media also incorporates a proprietary corrugation method which maintains uniform airflow and lower pressure while the media is saturated with oil.

High Performance Three-stage Filtration Improves Collection Efficiency at Every Stage

First Stage

DryfloMMCMMBThreeStage1_290A prefilter that removes larger mist droplets, metal dust and swarf captured by the collector. Wire mesh thin screen and polypropylene mesh are available.

Second Stage

A three-layer wrap of synthetic high-loft material collects small mist drops into larger oil droplets, which drain out of the mist collector.

Third Stage

Collects, coalesces and drains the finer mist droplets generated by metalworking applications. Along with vertically oriented pleats, the third-stage filter cartridge incorporates the Pleatloc™ media spacing system, which enhances drainage and provides a lower pressure drop, higher filtration efficiency and less re-entrainment of collected mist.


Long-Lasting Efficiency

The Dryflo cartridge is a proven, highly efficient mist filter that actually increases efficiency over time when collecting soluble oil or synthetic fluid. In tests conducted by the University of North Carolina (UNC), the Dryflo was shown to offer increased efficiency over time, resulting in longer HEPA filter life and reduced HEPA filter replacement costs.

Gauging Efficiency

Using UNC’s protocol for evaluating the cartridge efficiency, Dryflo mist collectors with HEPA final filter are a reliable, high performance filtration solution. To prolong HEPA filter life, the upstream filter stages must also be highly efficient. HEPA life depends on the cumulative loading it receives, which in turn, depends on the performance of the upstream collection stages.

Evaluating efficiency as a function of droplet diameter and pressure drop over 14 days, UNC protocol determines the size distribution of droplets generated during a variety of wetmachining operations. Droplet sizes ranging from 1.8 micron to 3.2 micron were tested to determine the average efficiency of Dryflo collectors on soluble oil and synthetic fluid.

Average Efficiency of Dryflo on Soluble Oil and Synthetic Fluid

Droplet SizeDryflo Collector with HEPADryflo Collector without HEPA
1.8 micron100%98%
3.2 micron100%100%
Collector DesignStandardOptional
Mild Steel Construction 
Inlet Gasket 
Inlet Collar 
Inlet Hopper with Legs 
Inlet Hopper with Vibration Isolators 
Inlet Hopper with Flex-Duct 
Inlet Hopper with Impact Separator 
Machine Mount 
Ceiling Mount 
Collector Stand or Cart 
Junction Box 
Drain Collection Container 
Cartridge FiltersStandardOptional
First-Stage Wire Mesh 
Variety of Other Prefilters 
High Efficiency First-Stage 
Dryflo Cartridge Filter with Wrap 
Fourth-Stage HEPA Filter 
Fourth-Stage 95% DOP Filter 
Paint SystemStandardOptional
Prime Coated Interior 
Textured Multi-Coat Paint Finish with 2,000-Hour Salt Spray Performance 
Custom Paint Colors 
Premium Duty Coating 
Electrical Controls, Gauges, and EnclosuresStandardOptional
Minihelic* Pressure Gauge 
Manual Motor Starter 
Type 12 (NEMA & UL) Motor Starter 
Remote Start/Stop 
Machine Tool Interlock 
Mounted and Prewired Motor Starters 
10-Year Warranty

* Minihelic is a registered trademark of Dwyer Instruments, Inc.

What size are mist droplets/particles?

Mist can generally be defined as a liquid droplet 20 microns in diameter or smaller. Oil-based fluids typically produce mist droplets that range from 0.5 microns to 10 microns. A smoke droplet is typically smaller, from 0.07 microns to 1 micron, and is a solid or liquid aerosol.

What determines the performance of a mist collector?

A mist collector can be characterized by pressure drop, efficiency, and flow rate. Pressure drops affects the energy required to pull the airflow through the system. The efficiency of the system determines how clean the air will be as it leaves the collector and flow rate determines how much air will be cleaned.