Ventilators for circular pipe consist of outer shell, impeller, external rotor motor and junction box1.Outer shell: Outer shell of ventilator is made of high quality zinc plating board and formed by drawing process with high pressure oil system which makes it precise in dimension, smooth in air channel, shiny in appearance, there's no surface scratch, no welding point, no need for second coating. it's much more environmentally-friendly and it has excellent corrosion resistance. With optimized channel designed by computer, the impeller has the maximum efficiency. the air intake and outlet have the same diameter in standard pipes, they are easy to be installed, repaired and cleaned. Intake and outlet diameter specs are 100 millimeter 125 millimeter 150 millimeter 160 millimeter 200 millimeter 250 millimeter 315 millimeter2. Impeller: With backward bending design for impeller vanes, the impeller can have a good match with outer shell. this will make the ventilator has the maximum air output volume, maximum efficiency and minimum noise.3. External rotor motor: the motor is a single-phase asynchronous motor with external rotor. the impeller is assembled to the external rotor and drive by rotor directly which makes the ventilator very steady while running and it gives high efficiency and long life. the motor is located in the middle of impeller which has high-speed cooling rate4. Junction Box: it's made of PVC material with fire-retardant fibers added by injection molding which has very good flame resistance. the junction box is outside the ventilator shell, so it's convenient for wire connection and disassembling.
