Gas between centrifugal fan blade impeller rotates, centrifugal force gains kinetic energy (pressure head) from around the impeller discharge, after orientation of volute-casing, making it to the fan outlet flow, so as to form a negative pressure in the center of the impeller, external air flow added, so as to make performance exhaust gas.
Motor through the shaft to transmit power to the fan impeller, impeller to deliver energy to the air, in the presence of rotation air produces centrifugal force, around the fan impeller blade to extend the air diffusion, at this point, the larger the fan impeller, accepted by air energy, is of pressure head (pressure) is. If the impeller cutting small, will not affect the air flow will only reduce air pressure.
Composed primarily of impeller and casing of centrifugal fan, small fan impeller mounted directly on the motor, large fan through the coupling or pulley and the motor connection. Generally one-side inlet of centrifugal fan, single-stage impeller; a large flow of double side air intake, with two back-to-back impeller, also known as the double suction centrifugal fan.
Impeller is a fan of main parts, its geometric shape, size, leaf number and manufacturing precision has a big impact on performance. Impeller by static or dynamic balance in order to ensure the steady rotation of fan. According to the different blades, impeller is divided into front, radial and backward three types. Prior to top slopes towards the direction of rotation of the impeller the impeller blades; radial impeller blade tip is radial, and straight and curved blade back to top to the rotation of the impeller the impeller blade tilt reverse.