Components Of An Industrial Centrifugal Fans

By Author: Neel Rao
Total Articles: 131
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The industrial centrifugal fans are used for moving air or gases, powdery substances, or tiny particles in a direction at an angle to the incoming duct in manufacturing process plants. The air flows along the centrifugal or radial direction, therefore they are sometimes called radial flow type fans.

Industrial Centrifugal fans are used to provide a high-pressure flow of air for conveying, combustion air, cooling, exhaust, ventilation, and other uses. The important parts of industrial centrifugal fans are fan housing, inlet and outlet ducts, impellers, driveshaft, drive mechanism fan dampers and vanes, fan blades, couplings, bearings, isolators, hoods, flanges, guards, fan discharge casing, impeller locking device, and shaft seal plates.

Fan housing enhances the efficiency of the fan by reducing noise and acting as a protection for moving parts like a hub, impeller, etc. In an industrial centrifugal fan, the stream of air gets into the impeller in an axial direction, gains acceleration due to centrifugal force as it flows through the fan blades, and gets released radially in 90 degrees direction from the fan housing.

Inlet ...
... and outlet ducts will affect the airflow pattern and performance of the fans. Inlet ducts direct the flow of air or gas by admitting required amounts of air whereas resistance is imposed to the air stream by outlet ducts. Ducts with sharp-cornered turns result in inefficient operation of the fan.

An impeller is a rotating device consisting of several fan blades mounted on a hub with a drive shaft that drives the air or gas in the desired direction with increased pressure. For industries with large capacity plants which need high-pressure airflow, custom-designed impellers are used such as multistage impellers and double inlet impellers in which two or more impellers with a single inlet are mounted back to back on the same shaft.

The driveshaft is a rotating device that holds the blades and impeller. It controls the speed of the fan rotor through different drive mechanisms like a belt driven, direct driven and variable. The design of the drive shaft depends on the velocity of inlet gases and the weight of the installed impeller. The fan speed is directly proportional to the motor speed in direct driven fans because in these fans the shaft is straightaway connected to the motor shaft of the fan. The rotor speed is fixed in belt-driven fans unless the belt gets misplaced from its position because in these fans the motor shaft and the fan shaft are attached by the belt which is mounted on the sheave. Couplings are used by direct driven & variable-driven fans (using VFD), to get the desired variable speed by establishing a connection between the motor shaft and rotor shaft. Some of the industrial centrifugal fans consist of electronic variable speed drives that can automatically control the fan speed at the desired level.

The industrial centrifugal fans are robust in structure, typically drum-shaped devices which consist of several fan blades mounted around the hub. In the fan housing, the hub turns on a drive shaft. The air or gas enters into the impeller from the side of the fan wheel, turns 90 degrees and accelerates due to the centrifugal force as it flows over the fan blades and gets released from the fan housing.

Reitz India primary air fans and secondary air fans from Reitz India are custom designed to serve the needs of various processes in industries like cement, iron & steel, power plants, fertilizers/ chemicals and more. As a top quality industrial centrifugal process fans, Reitz India has set a benchmark in delivering superior fans with high quality features and better industrial standards.