11.2.6 Pressure losses

For sucking off dust-laden air both smooth pipes as well as air ducts can be used to set up connection with the filter plant.

Air ducts are plastic hoses that are reinforced by a spiral made of spring steel. According to the respective spiral distance the air duct can be used for very different vacuums.
As a standard, air ducts are available at diameters ranging from 250 – 2400 mm and in single lengths of 5 and 10 m.

The pressure loss amounts to about 50 Pa per m/air duct (NW 300), as regards a smooth pipe this value is only about 10 Pa per m/pipe (air velocity about 20 m/s).

The total pressure loss in a pipe transporting air should not exceed the value of ventilator compression, if possible. If the pressure loss of the plant is higher than the ventilator compression the air volume flow decreases.