Using Centrifugal Blowers in Industrial Applications

Blowers are used in industries when there is a requirement for larger volumes of air flow at higher pressures. A fan with higher pressure ratio (output pressure / input pressure) can be called as a blower provided it produces pressures as high as 1.20 kg/cm2. Like fan systems, blowers are widely used in industrial processes where a constant flow of air/gas is needed at higher pressures such as conveying material in dust collector systems, combustion air for burners, drying & cooling, general ventilation & circulation of air and so on. Blowers with higher efficiency are also used in industrial vacuum systems where suction or negative pressures are required.

Industrial blowers are broadly divided into two types, centrifugal blowers and positive-displacement blowers. Centrifugal blowers have several advantages over other blower types because of their wide operating ranges and high speed capabilities.

Centrifugal blowers

• Working

Centrifugal blowers are constant volume devices that are designed with high speed impellers or blades typically rotating at about 15,000 rpm.
The speed of the air stream entering into the blower is increased by the impeller or blades, where it gains kinetic energy and accelerates with higher pressure through outlet in radial direction.
Like centrifugal fan systems, these blowers also have different drive mechanisms such as belt, variable and direct driven. To adjust the air flow rates, centrifugal blowers are fitted with dampers & louvers, ducts and other similar airflow resistant components.
A centrifugal blower can be single and multi-stage unit and can have different blade orientations such as radial, forward curved and backward curved. Often, single stage centrifugal blower is used when a uniform airflow is required whereas multi-stage blower is useful when there is a requirement for varying flow of air at a fixed pressure.
Centrifugal blowers are basically classified into three types based on their ability to generate pressure during operation. They are low pressure, medium pressure and high pressure centrifugal blowers.

• Benefits

Since centrifugal blowers operate at high impeller speeds, they are useful in industrial applications to move bulk volumes of air at low-to-medium static pressures in radial direction.
The various blade configurations of centrifugal blowers allow them to operate in wider range of environments and in diverse airflow/pressure conditions.
Centrifugal blowers can develop more pressure at a given rotational speed when compared to other type of blowers at the same rotational speed.
Since centrifugal blowers have high horsepower capability than the other blowers, there will be less overloading and possible damages to motor.
As centrifugal blowers are available in multiple sizes & blade arrangements, they can be better choice for places where space is a premium.

• Industrial applications

Centrifugal blowers are widely used in industrial applications where there is a requirement for constant flow of larger volumes of air such as in ventilation, combustion, transporting materials, cooling and heating systems, dust control, air conveyor systems, industrial vacuum applications and in other industrial processes.

Centrifugal blowers vary on the basis of their air flow capacity, blower type, blower dimension, and maximum operating pressure. Based on the requirement, blowers of various types can be customized and installed to serve the needs of diverse industrial applications.