Buyer’s Guide: Types of Centrifugal Blowers
If you are like most people, then you probably don’t understand the difference between fans and blowers or what makes centrifugal blowers unique from the rest. On top of that, there are several different types of centrifugal blowers and understanding the advantages and disadvantages of each type can seem like a daunting task.
This buyer’s guide will tell you everything you need to know about centrifugal blowers, including how they work, what they are used for, and which ones are better for particular situations.
What Is a Centrifugal Blower?
The distinction between a fan and a blower comes from the amount of pressure that they can produce. Any fan that can produce pressures that are greater than 1.2 mg/cm2 at a high flow rate is considered a blower.
A centrifugal blower, sometimes referred to as a centrifugal fan, is a pump or motor that moves and circulates air. It pulls the air inside the blower and then pushes it out at a 90º angle. The two main components of a centrifugal blower are the impeller and the motor.
Some blowers can pull and push air at lower than a 90 degree angle; these fans are called mixed-flow fans and shouldn’t be confused with centrifugal blowers.
Centrifugal blowers built for industrial purposes are constructed with protective housing that increases durability and ensures that no foreign objects clog any of the moving parts. Thanks to rotating impellers, centrifugal blower fans are able to increase the speed and volume of an air stream.
They rely on curved blades to drag air in a circular motion with centrifugal forces speeding up airflow radially and outwards. These move air outward through ducts or tubes, and provide a stronger and more stable airflow than axial fans do. Even smaller centrifugal blowers have a horsepower of at least 50, while more heavy duty blowers can have horsepower reaching into the hundreds.
Applications of Centrifugal Blowers
Centrifugal blowers are very useful for industries that require larger volumes of gas and air flow at higher pressures. You’re likely to find them incorporated into building ventilation systems, and they’re also often used for industrial processes to transport gas or materials. Air pollution control systems also utilize centrifugal blowers.
Other applications include dust collection, combustion air for burners, drying and cooling systems, air circulation, filter flushing, gas boosting, and sewage aeration.
The pressure to volume curve is the key: centrifugal blowers work better than axial types when working against a high pressure drop. This makes them invaluable for many components of processes for a lot of industries mentioned above.
Types of Centrifugal Blowers
There are several different types of centrifugal blowers, and each one has its own advantages and disadvantages. Here are some of the options that are commonly used for industrial purposes.
Radial Blade Blowers
Radial blade centrifugal blowers use an impeller with multiple equally-spaced flat blades that extend perpendicular to the direction of the wheel rotation. The blades are much heavier, deeper, and narrower than inclined blades. They produce medium to high pressure and are well suited for material handling and in some moderate pressure industrial applications.
Airfoil Blade Blowers
Blowers that use airfoil blades have hollow backward inclined blades that are suitable to handle large volumes of clean air at low to moderate static pressures. These blowers are very efficient and run at greater speed than blowers with inclined blades. As they can handle large volumes of air, these blowers are typically used for HVAC systems, air pollution control, drying and filtration, and other industrial processes.
Radial Tip Blowers
Radial tip centrifugal blowers have a more compact design than their airfoil and backward curved brethren and are ideal for high-volume flow rate applications where the pressure requirement is also relatively high. Radial tip blowers have moderate material handling capabilities but are more efficient than radial blade fans. They are generally used in dust collection systems and general ventilation applications.
Inline Centrifugal Blowers
Inline centrifugal blowers have rugged construction with backward inclined type wheels enclosed in a tube-axial casing. These are medium-duty fans that are less efficient than other varieties and are commonly used in low pressure industrial applications.
Finding the right centrifugal blower can be difficult, but understanding the advantages and disadvantages of each one can help you make the correct decision. If you are looking to purchase a centrifugal blower, visit C&B Equipment and take a look at all of the options we have to offer.