Blowers

Blowers are air blowers or blower systems which provide air and gas movement in ventilation, circulation and drying applications. Blowers and fans are used in industrial, manufacturing, commercial and retail settings to ventilate, circulate, cool and dry. Industrial blowers reduce heat levels in factory operations; moisture in bathrooms, greenhouses, gyms and spas; smoke and odors in cooking and processing applications, and gaseous fumes in chemical and oil manufacturing facilities. Ventilating exhaust fans replace stale or contaminated air in hot, dusty or smoky workplaces and restaurants with fresh, normal temperature air. Industrial fans and air blowers refresh or lower air temperatures in cooling applications, while high velocity fans assist in product drying applications. Blower fans are industrial blowers that also use a metal fan for cooling and drying applications. Centrifugal blowers and regenerative blowers are impeller-based, high-efficiency blowers commonly used in ventilation, cooling and drying applications as well as pneumatic bulk conveying; centrifugal and regenerative blowers are also used in reverse to provide vacuuming action in packaging applications.

A wide spectrum of industries use blowers for various ventilation, air purifying, conveying and drying applications, including agricultural, photography, automotive, food processing, packaging, pulp and paper, printing, welding and textile manufacturing industries. Regenerative blowers are also used to provide aeration for ponds, sewage and spa pools. Construction materials for blowers include durable plastics, metals or a combination of both. The size variance between industrial blowers for various applications can be immense. Some units are mounted into the framework of a system or piece of equipment, complete with vibration absorbent brackets which house both the fan itself and its power supply. These large, self-contained systems are only used in large manufacturing or air circulation applications. Portable air blowers are much smaller and are transportable from place to place for use in temporary circulation or air transfer, such as at construction sites or when cleaning up spills and water damage.
 
Fans and blowers are made using one of two main designs: radial or axial. Air currents are generated from circulating blades which direct flow based on their aforementioned designs. Centrifugal blowers, unlike other blower types, use impeller blades which take in air through the blower's center and force it out at a perpendicular outlet; this process increases airflow pressure and velocity.  Blowers and fans are classified based on how the fan is constructed; three classes were developed and are recognized by the Air Movement and Control Association. In most cases, larger class numbers correlate to greater performance and cost of purchase. This classification is not required by the government of all blowers, so other functional and reliable blowers may be classified under other rating systems and standards.
 
Blowers are essential in many manufacturing processes and facility air pollution control systems, as well as many other drying and finishing processes. Air blowers and fans provide healthier areas through the reduction of odors, air pollution, contamination and smoke, and they may also provide environmental benefits through a decrease in heat and humidity levels. Industrial blowers are available in many configurations of velocity, pressure, airflow direction and speed. When choosing a blower, manufacturers and facility managers consider the environmental conditions, pressure levels and surface areas of the application.

Blowers Image Provided by Hartzell Fan

Blowers Image Provided by the National Turbine Corporation

Blower Types

• Air blowers blow or pump air through openings in a system. Applications include pools, Jacuzzis, and spas, fish tanks and aquaculture applications.
  
• Axial flow fans are used for ventilation purposes. In axial flow fans, air maintains parallel movement within the fan, and maintains linear movement during emergence from the fan.
• Blower Fans are industrial blowers that also use a metal fan for cooling and drying applications.
• Centrifugal blowers and fans are more useful in air pollution control than axial flow fans are. In centrifugal blowers, air maintains perpendicular movement in relation to the fan shaft while in the fan system, and emerges rotationally from the fan outlet.
  
• Corrosive duty fans are specially designed for use in corrosive environments or any application that involves chemical or gas movement. Fiberglass is often used in this type of construction.
  
• Crossflow blowers, or tangential blowers, release air after two cycles of circulation within the blower. Crossflow blowers are found in applications involving large areas requiring low pressure and high levels of airflow.
  
• Displacement blowers are used in applications that transfer large amounts of air for use in compression situations such as in the automobile industry.
  
• Electric blowers require an electric motor for operation. Electric blowers cover a number of products, ranging from hair dryers used in beauty salons to leaf and lawn blowers.
  
• Exhaust fans are ventilation systems used to reduce or eliminate odors, smoke, moisture or stale air from an area by removing the offensive air and replacing it with fresh air. Exhaust fans are common in kitchens, restaurants and bathrooms.
  
• Gas blowers are used to control gas flow and gas pressure. Gas blowers process methane, natural gas and other gases in gas well and chemical applications.
  
• High velocity fans provide high levels of air movement.
• Industrial fans are made from different materials than residential or consumer fans and are used in industrial settings.
• Low pressure blowers are used in applications where oil free air and almost silent operation are desired. These blowers tend to be small and use a small amount of energy to function.
  
• Power blowers are used in greenhouse and lawn and garden applications, involving movement of air over a large area or heavy-duty air movement.
  
• Regenerative blowers are used in the paper, photography and recreational industries for applications including ink and film drying and pool and spa aeration. During operation, air enters the blower and moves centrifugally out of the blower through the rotational force of the blower blades; however, during this process of rotation some of the air drops past the blade and moves through the cycle again, which is why the blower is known as a regenerative blower.
  
• Turbine blowers generically refer to any type of blower that is built in a turbine style, consisting of rotating blades, which create the air flow that is then blown.
  
• Vacuum blowers are called such because they essentially derive their blowing power via a vacuum which can either inhale or exhale a vast amount of air. When vacuum blowers exhale, they technically are not vacuums.

Blower Terms

Air Changes - The amount of time, expressed in minutes, that is takes for industrial blower systems to replace air in an area.

Air Distribution - The delivery of outdoor or conditioned air via industrial blowers to various spaces in a building, usually by mechanical means.

Air Velocity - The rate and direction of air movement produced by industrial blowers.

CFM - Abbreviation for cubic feet per minute; a measurement of the amount of air industrial fans and industrial blowers move through ventilation and circulation during operation.

Circulation - The process used by industrial blowers and industrial fans for moving air around within a specific area.
 
Cross Ventilation - Air that enters on one side of a room and leaves on a different side of the same room as it is blown by industrial blowers or industrial fans.
 
Damper - The mechanism responsible for the regulation of airflow by industrial fans or industrial blowers systems; dampers consist of inlet dampers, which regulate airflow into industrial blowers or industrial fans systems, and outlet dampers, which control air movement out of industrial blowers or industrial fans systems.
 
Fan Blade - The fan component extending from the hub of industrial blowers or industrial fans that rotates, cutting into the air and producing air movement. Fan blades may stick straight out in a radial position, curve forward in the direction of fan wheel rotation or curve backward.
 
Fan Drive - The fan mechanism responsible for controlling the movement of the fan wheel on industrial blowers or industrial fans, including fan wheel speed.
 
Fan Wheel - Fan component consisting of a hub and blades, which rotate about the wheel in order to produce air movement of industrial fans or industrial blowers.
 
Hub - The point on an industrial fans wheels from which the fan blades extend.
 
Multizone - A building or part of a building that comprises a number of zones or cells.
 
Static Pressure - The amount of resistance in a circulation or ventilation system that industrial fans or industrial blowers must surmount to ensure proper air movement.
 
Total Pressure - The total amount of pressure, measured in Pascals, that industrial fans or industrial blowers produce, including both the static pressure and the velocity pressure.
 
Velocity - The rapidity of air movement in a ventilation system produced by industrial blowers or industrial fans, measured in feet per minute (fpm).
 
Velocity Pressure - The amount of pressure in a circulation or ventilation system resulting from air movement from industrial blowers or industrial fans.
 
Ventilation - A process of industrial fans and industrial blowers in which air is moved into, out of and between different areas. Ventilation is used to replace old, stale, odiferous or contaminated air with fresher, cleaner air.