Centrifugal fans, compared to other types of fan products, may allow full or reduced starting, But notice that the current at full voltage starting is about 5 ~ 7 times of rated current, and the distance of step-down starting is proportional to the square of current. When the capacity of power grid is insufficient, it should be started by reducing voltage.
In terms of performance, the performance of centrifugal fans is not only related to the movement of the fluid in the impeller, but also to the components passing through after the impeller is out. The spiral chamber and diffuser are mainly composed of fan shell. The side of the spiral chamber is Archimedes spiral or logarithmic helix, and some are drawn by approximate Archimedes spiral, and its axis is rectangular, and its width is invariable. Made of steel plates.
The air velocity of outlet section spiral centrifugal fan room is still very large, therefore, a diffuser in the spiral chamber, from the spiral chamber to the diffuser outlet velocity distribution is not uniform, and the deviation to the impeller rotation direction so that the diffuser is made of expanding to the impeller side.
The intake box of the centrifugal fan is designed to meet the demand of inlet turning of fan. The intake box of the centrifugal fan is designed to meet the demand of the fan inlet and turn. It can make the air flow into the impeller even in the case of the minimum loss. In addition to the parts mentioned above, the centrifugal fan also includes impeller, guide vane, rotary shaft, inlet horn tube, housing and moving vane regulating device.
Most of the blades of centrifugal fan are wing twisted blades, which are made of twisting blades to ensure that there are equal energy heads along the blade radius under the design conditions, and when the impeller rotates, the circumferential velocity at the top of the blade is large and the energy generated is also large.http://www.jnblower.com/