Strict guidelines apply in the industrial environment. Pressure-resistant fans are subject to the Pressure Equipment Directive and are designed to withstand high system pressures.
Pressure-shock-resistant fans can withstand a brief high, defined pressure increase, e.g. due to explosions.
1. Pressure-resistant design:
In the case of pressure-resistant designs, the pressurized components (housing, inlet pipe, flanges and screw connections, seal) must be able to withstand the working pressure completely without noticeable deformation.
The design of the housings is carried out in accordance with DIN EN 13445-3:2016-12, using the material with 1.5 times the safety against yield strength.
The standard wall thicknesses for housings are designed so that an overpressure of at least 25,000 Pa (= 0.25 bar) can be transmitted at room temperature.
Only a floating labyrinth seal with the appropriate number of rings is used here as a shaft seal.
2. Pressure-shock-resistant design:
In pressure-shock-resistant designs, the components must withstand the pressure wave once in the event of an explosion. Deformation of the components is permissible; only the component must not burst.
The design of the housings is also carried out in accordance with DIN EN 13445-3:2016-12 in conjunction with VDI 2263. The material with a 1.0-fold safety factor against the yield strength is used.
The standard wall thicknesses for housings are designed so that a pressure shock of at least 40,000 Pa (= 0.40 bar) can be transmitted at room temperature.
According to VDI 2263-3, a water pressure test with 90% of the pressure shock is also required here.