System Components

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ESA Components

600 600 ESI
Bin Cover

Bin Covers

600 496 ESI
Bin Cover

Bin Covers

MacDonald Steel Bin Covers are the most effective way to handle your wood processing by-product. Our bin cover is designed to fit any standard 40 cu. yard container.

Sawdust and wood waste is discharged through an air lock into the bin cover inlet. Once the bin has reached the predetermined fill level, the operator is notified that removing and replacing the full bin is required.

The MacDonald Steel Bin Covers bolt directly on to your bin providing maximum fill with minimum effort, the bin covers are manufactured to MacDonald Steel’s high standards with:

  • Heavy duty screw flighting
  • High torque direct drive power transmission
  • Heavy gauge steel construction
  • Quick and easy disconnect
  • Electrical interlocks to provide optimum safety
  • Illuminated operator friendly control panel
  • Single or dual bins available

The bin cover can be removed and replaced with an empty bin to provide uninterrupted production.




297 297 ESI


We provide quality diffusers. The MacDonald Steel Air Return Diffuser Duct is used where clean filtered air is returned back to the customer’s building to conserve heat/cooling energy and/or to maintain building air pressure.

The ducts are installed at the end of the return air duct and are designed to evenly distribute the air to a larger area, at a lower velocity than that inside the duct system.

This is achieved through a series of holes situated on the topside of the duct, which are sized and spaced to achieve an air exit velocity of approx. 2000 feet per minute, based on a duct system velocity of 4500 feet per minute.

MacDonald Steel Air Return Diffuser Ducts are of 14 gauge welded steel construction, and are available in a range of sizes from 11” diameter up to 26” diameter with or without angle ring flanges.

Diffusers in sizes from 30” diameter to 42” diameter are available equipped with angle ring flanges only and are also equipped with a stiffening angle ring at mid-length.

diffuser -1

Please contact us for more information our diffusers.


328 328 ESI

We Design Gas Turbine Silencers


We provide silencers for many industries. For example, we design gas turbine silencers.

MacDonald Steel silencers are designed to be installed on low pressure pneumatic conveying systems. The sound attenuation medium dampers noises being conveyed in the air stream as they spiral through the silencer.

They are manufactured of HRS black iron, all-welded construction, painted with one coat of primer and one coat of finish enamel.

The sound attenuation medium is sandwiched between an inner perforated skin and an outer solid skin.

MacDonald Steel silencers are available in a large range of diameters and related lengths.

Please contact us for more information on silencers, including how we design gas turbine silencers.

Switch duct


600 600 ESI
Switch duct


The MacDonald Steel Air Diverter unit is designed for use in the clean air return duct of a filter system, to direct clean air either to the atmosphere or return it to the building to save heat in the winter months. Our diverters can be equipped with leak detection/spark detection.

The modular design and square, symmetric flanges of the diverter housing allow the flexibility of mounting in a wide range of orientations.

Standard duct transitions and an assortment of weather hoods are available as well as adapters to mount the diverter directly to the outlet flange of our BC fans.

Custom fittings can also easily be fabricated to suit any customer’s needs.

The Air Diverter unit consists of a rugged steel housing containing a pivot-mounted steel diverter blade which closes off the unused leg of the diverter, directing the clean air to the other leg.

The pivoting mechanism is connected to a shaft which is located and supported on heavy-duty flange-mounted ball bearings, for smooth operation.

Each size of Air Diverter is available in three versions:

  • manually operated
  • electric-motorized linear screw actuated
  • electric solenoid controlled air cylinder actuated

Leak Detection/Spark Detection

Please contact us for more information on our diverters and our leak detection/spark detection equipment.

High Pressure Systems

250 250 ESI

Waste Reduction With High Pressure Air

MacDonald Steel High Pressure Blower Systems are used when low pressure systems are unable to convey solid material either due to excessive volume of material or over long distances. The systems provide waste reduction with high pressure air.


High Pressure Blower Packages have many features. Intake filters provide clean air, eliminating the possibility of contaminants entering the blower. Intake and discharge silencers minimize noise pollution. Pressure control panel monitors the operating pressures. High efficiency motor and drives complete the standard package.

MacDonald Steel High Pressure Systems use feeders designed to introduce bulk solids, producing maximum efficiency and economy.

Our unique chevron design reduces rotor end thrust, provides uniform loading and reduced wear. Out board bearings stay cool and clean. Shaft seal packing glands prevent air and material leakage. The T Injector with integral check valve minimizes pressure loss.

Please contact us for more information on our high pressure systems and waste reduction with high pressure air.

Rotary airlock

Rotary Air Lock

600 600 ESI
Rotary airlock

Rotary Air Lock in Canada

Our rotary air lock is built in Canada and is designed to efficiently transfer non-stringy materials from one air system component to another, ensuring maintenance of a required vacuum or to prevent pressurization.

The air lock maintains a tight, positive air seal by keeping a maximum of the six flexible neoprene steel backed wipers in full contact with the interior housing at all times.

The neoprene wipers are bolted to the vanes of the rotor tips for ease of maintenance.

The rotors are open-ended. The rotor housing is heavy-duty steel construction with a removable side plate to provide easy access and maintenance of the rotor.

The MacDonald Steel rotary air lock is manufactured in Canada, in a range of sizes. All packages are supplied complete with drive motor package to suit your displacement requirements. Optional zero-speed sensor package is also available.