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MVA 02 rev 5 - December 2017
2.4
Description of fan
Taking the fan shown in Fig. 2-5 as an example, an axial fan is generally constituted by the following
components:
an impeller that rotates to impart the necessary energy to the fluid (1);
a casing housing the impeller, with a cylindrical shape (2);
a motor support base with respective stays (3);
guards to prevent accidental contact with all rotating parts (4);
The power that permits rotation of the impeller is provided therefore by a motor (5), usually but not
exclusively electrically driven, linked to the impeller directly or by other organs of transmission, such as for
example:
a support complete with bearings and drive shaft (6);
transmission by drive belts and trapezoidal pulleys (7) or flexible couplings to transfer the energy
provided by the motor;
a cooling fan between the impeller and the support, if the fluids are to be moved with an operating
temperature greater than 60°C (8)
For versions 8 and 12 (see Fig. 2-1) a common base is normally provided to support the fan, the motor and
the transmission.
Fans may be supplied with different construction characteristics that may also include other components not
indicated in the above descriptions and that must be defined for each specific case. Fans may also be fitted
with additional accessories (as shown o
n pages 187 to 204 of the “Axial Fan Catalogue”).
FVI fans are always supplied without control and monitoring systems.
Fig. 2-5 Example of version 9 with fan components indicated
