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6 Fans and Flow Control Devices
Fig. 6.5 Panoramic view of a main centrifugal fan. These fans are very appropiated for deep mines
in which high pressures are required. Courtesy of Zitron
a)
b)
c)
Fig. 6.6 Configuration of the axial fans. Layout: a vertical, b horizontal with horizontal output,
c horizontal with vertical output
increasing the airflow rate in the same proportion. These conditions usually occur in
the case of mines with high airflow resistance.
In the parallel ventilation system, the fans take air from the fan drift and discharge
it into the atmosphere (Figs. 6.8b and 6.9). In this case, the pressure of the system
does not increase, however, the flow does. This system can be used in mines with
low equivalent resistance.