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Fluidizes Materials in Bins, Hoppers and Silos
External Mounting Available
No Damaging Vibration
Evasser Bin Aeration Device


The Evasser bin aerator from Monitor Technologies is an aeration device used to promote the fluidization and flow of dry bulk powders from a storage vessel (bin, silo, hopper) without the noise and damaging vibration caused by pneumatic or electric vibrators. The Evasser aerator is small, compact and capable of aerating many types of bulk powders and granular solids in bins, hoppers and silos. The Evasser can discharge air up to 80 psi (5.5 bar) to move settled materials. Once material is flowing the Evasser can be used to maintain flowability of material with a constant 2 to 5 psi (0.14 to 0.35 bar) supply of air.

Unlike other types of aerators that use cotton or canvas to diffuse the air, the Evasser is less likely to be bound or clogged due to moisture and can be more effective as it directs air flow to 'sweep' the bin wall. In addition, the Evasser is not as prone to back-flow of material as the standard neoprene boot expands to let the pressurized air out and contracts when the air is shut off blocking the air outlets from material backflow.

The Evasser bin aerator is available with a convenient external mounting plate. This means that installation of the device can be done from outside of the bin making it ideal for use in replacing worn and plugged air pads. In addition, with no moving parts or filters to clean or replace the Evasser requires virtually no maintenance.

.: Principle of Operation

.: Applications

.: Features

.: Accessories

.: Specifications

.: Warranty

Click Here for Evasser Selection Guide (PDF)

Principle of Operation

The single Evasser bin aerator operates by continuously introducing air into a mass of stored powder. When first conveyed into a storage vessel, the powder is a highly aerated mixture of air and particulate. In this state, the mixture flows quite easily. As the material settles, the particulate and air separate. The material decreases in volume and increases in density (it packs), and in turn it begins to behave like one solid mass rather than a fluid mixture of particles. The Evasser replaces the naturally lost air and increases and maintains the air-to-particulate mixture ratio, thus allowing the material to flow.


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The most effective aeration of dry bulk materials is typically achieved by the use of four rows of Evassers, one row located in each quadrant of the slopping bin bottom. With aerating dry powders the Evassers will normally be spaced 18in on centers, with the lowermost units located close to the outlet where most of the bridging starts. On granular materials the location of the Evassers will vary with the material being aerated and the configuration of the bin. In all cases, please consult with the Monitor application engineers that are ready to provide you with the best recommendation for your specific material flow problem.

Typical Applications include, but are not limited to:




Soda Ash



Carbon Black

Fly Ash




Typical effective radius of 12 inches (305mm)

Compact and low cost with virtually no maintenance

Available in cast iron or 316 stainless steel

Black Neoprene boot or optional white FDA Neoprene boot



The Evasser bin aerator is available in several configurations. The Evasser itself can be provided in either cast iron or 316 stainless steel construction. The Evasser is normally supplied with a black Neoprene boot. A FDA approved white boot is also available. For high pressure or high temperature applications where the boot is not acceptable, a sintered metal insert can be provided. In addition, each of these configurations can be provided with or without the external mounting plate.



Air Supply/Consumption:

Air Supply :

Continuous clean, dry air 3 to 5 psid (0.2 to 0.35 bar) (the difference between the air feed pressure and the internal vessel pressure)

Air Consumption:

Typically 3 psi (0.2bar) / 3 scfm (0.085m³/min)

Materials of Construction:


Cast iron (Option 1, 1A, 3 and 3A)
316 stainless steel (Option 1SS, 1ASS, 3SS and 3ASS)

Mounting Plate (optional):

Mild steel (Option 3, 3A)
316 stainless steel (Option 3SS, 3ASS)

Gasket (mounting plate):

Cork (up to 175°F/80°C) for mild steel mounting plate
White Nitrile (up to 175°F/80°C) for stainless steel mounting plate

Boot (standard):

Black Neoprene (up to 175°F/80°C)

Boot (optional FDA):

White Neoprene (up to 175°F/80°C)

Sintered Metal Insert (optional):

Bronze 90 micron (up to 900°F/480°C) or 40 (optional) micron filter for extra fine materials (up to 900°F/480°C)

Air Inlet Connection:

1/2" NPT coupling



Monitor Technologies warrants each evasser it manufactures to be free from defects in material and workmanship under normal use and service within two (2) years from the date of purchase. The purchaser must notify Monitor of any defects within the warranty period, return the product intact, and prepay transportation charges. The obligation of Monitor Technologies LLC under this warranty is limited to repair or replacement at its factory. This warranty does not apply to any product which is repaired or altered outside of Monitor Technologies' factory, or which has been subject to misuse, negligence, accident, incorrect wiring by others, or improper installation.



Updated November 2017

Mass Flow Measurement Systems
The QuantiMass in-line mass flow sensor measures the flow of quantities in pneumatic conveying & free-falling processes. The sensor is based on the latest Microwave Doppler Effect technology and provides fast, in-line / on-line measuring without the use of weight scales.
The sturdy, non-intrusive design of the sensor minimizes maintenance. In addition, the compact size of the sensor makes for easy installation into existing processes. Suitable for powders, dust, pellets, and granular up to 0.75 inch (2cm).

Ultra Series-Includes controller
PRO Series-Includes transmitter

A practical application for the QuantiMass would be to monitor material flow rates to verify blending mixture ratios.

Principle of Operation:
The QuantiMass Mass Flow Measurement Sensor / Meter is designed with the latest microwave technology and is used to continuously quantify the flow of powders & solids being conveyed in metallic pipes. The QuantiMass is based on technology that has been developed and proven over several years. The measurement process of the sensor is centered on the Doppler effect. The mass flow-rate is determined by evaluating the frequency and amplitude changes during the measurement process. Particles at rest, such as deposits, do not influence the measurement. All powders, dust, pellets and granules can be measured reproducibly, up to the size of 0.75 inch (2cm). The QuantiMass sensor is suitable for continuous in-line / on-line measurements in pneumatic conveying or in free-fall pipelines.

Click here for more information on the QuantiMass
or contact Monitor Technologies LLC at
Tel.: 800-601-6319 in the USA and
Tel.: 630-365-9403 worldwide.
>>Download QuantiMass Ultra Bulletin

>>Download QuantiMass PRO Bulletin

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