Tube fans represent a technically perfect solution, uniting the advantages of the axial fan - straight air flow and easy installation - with the high pressure stability, low noise level and high efficiency of the radial fan.

The sizes RK 100 - 315 are equipped with an attractive, strong and heavily inflammable light grey plastic casing with integrated terminal box and guide vane. The casings of sizes RS 100-355 are powder coated sheet metal. Backwards curved radial impellers made of sheet steel or plastic. The impellers are fitted directly onto the rotor of the external rotor motor. These units are balanced at two levels according to G 2.5 of DIN ISO 1940.

Tube fans are driven by an external rotor motor, protection class IP 44, fitted in the radial impeller. Electrical construction is according to VDE 0530, insulation material class B comes with additional moisture impregnation. From size RK 150 up to size 315 all units are equipped with thermal contacts mounted in the motor windings. Fans are delivered ready for installation in individual boxes.