Industrial fans and blowers move air and powders in industrial and commercial settings. They commonly provide air circulation for personnel, exhaust, or material handling.

Fans and blowers can provide spot cooling in industrial and commercial buildings where air conditioning is not feasible or is too costly. Circulating fans can also be the solution to problems such as heat stratification, dampness, and general air stagnation. They can provide general ventilation in heavy-duty commercial and industrial applications including factories, warehouses, gymnasiums, and underground parking garages. Industrial fans and industrial blowers are frequently used for high volume, high static pressure applications. Blowers are often used to exhaust foul air and replace it with fresh, outside air.

Types of Industrial Fans and Blowers

There are a variety of industrial fan and blower types available, including:

• Axial fans include propeller vans, vane axial fans, and tube axial fans. With these designs, the fan blade circulates parallel to the air flow.
• Positive displacement (or rotary lobe) fans consist of multiple co-rotating, serpentine shafts that mesh to move air and gases in a controlled manner. The shafts mesh so tightly that backflow is prevented. Typically, bi-lobal fans and tri-lobal are used to recirculate gases in process equipment when environmental consistency is required.
• Centrifugal fans include products with many different blade configurations, such as forward curve, backward curve, air foil, backward incline, and radial tip. With centrifugal fans, the fan blade rotates perpendicular to the air flow.

Types of centrifugal fans. Video credit: ebm-papst ANZ / CC BY 3.0

•  Crossflow fans draw air from the full radial inlet site of a rotating vane and expel the air on the opposite side through a smaller orifice. Crossflow fans find use where plenum space is small and where a concentrated stream of air is desired.

Configuration

Industrial fans and industrial blowers are available in a number of configurations, usually based upon the location in which they are to be placed or mounted. These include duct fans and blowers, roof and ceiling ventilators, wall and panel mount fans, pressure and volume blowers, freestanding fans, and plenum fans. Duct fans and blowers are designed for in-line duct mounting via flanges or support braces. Wall and panel mount fans have mounting brackets or flanges specifically for wall installation or exhaust.

Industrial fans and blowers have either a forced draft or induced draft design. Forced draft refers to the movement of air under pressure. Forced draft fans and blowers are so named because they "force" air to move. Induced draft refers to the movement of air by means of an induced partial vacuum.  Induced draft fans and blowers "draw" air.

The drive system for industrial fans and blowers can be either direct or belt driven. In direct drive fans, the electric motor is coupled directly to the fan shaft for direct power transmission. In contrast, belt drive fans are powered by belts and sheaves or pulleys. Typically one sheave will be mounted on an electric motor and the other on the fan shaft and the two are connected by a belt.

Applications

Industrial fans and blowers are used in a wide range of applications.

• Air handling units and HVAC (Heating, ventilating, and air conditioning) systems incorporate fans such as plenum fans and duct fans to move air in buildings and enclosed environments.
• Exhaust fans draw air out of a building or workspace that may be contaminated with smoke, noxious gases, fumes, and other undesirable contaminants.
• Material handling and pneumatic systems contain fans propel granular materials such as plastic resin pellets, grains, and powders. Such systems move these materials between storage containers and to production equipment.
• Fans for personnel and workspace use—such as mancoolers, box fans, and pedestal fans—are advantageous in locations where a draft of air can give comfort to personnel in hot locations.
• Pressure blowers typically have a standard factory floor mounting configuration in which the blower resides in an enclosure designed to give a common mounting platform for a blower and its electric motor. The enclosure can be mounted on vibration isolators and may be referred to as a unitary base or vibration isolation base.
• Process cooling fans are used in large scale industrial process equipment such as heat exchangers, cooling towers, process dryers, and where high throughput over long durations in challenging environments is required.

Standards

Industrial fans and industrial blowers are often classified with a numerical designation based upon their performance characteristics. The Air Movement and Control Association (AMCA) develops standards and provides certifications to ensure fans and blowers meet rating requirements.

AMCA511--Certified product ratings for air control devices

Resources

Tuthill Vacuum & Blower Systems Sizing Tool

Image credit:

Aerzen USA Corp. | Air Impurities Removal Systems, Inc.