AX-630 Long-Cased Axial Fan

An axial fan moves air along the shaft axis, which makes it efficient at volume and weak at pressure. The AX-630 is sized for the duty most building extract systems actually present: a lot of air against a few hundred pascals.

Case length matters

The long case encloses the motor and gives room for a downstream guide vane set, which recovers some of the swirl the impeller puts into the air. On a short case the swirl leaves with the air and shows up as pressure loss in the first bend downstream.

Blade pitch

Blades are aerofoil section, set at a fixed pitch chosen at order. Getting the pitch right matters more on an axial fan than most buyers expect: the same impeller at two pitch angles gives two different curves and two different absorbed powers, and the wrong one either starves the system or trips the overload.

Stall

Axial fans have a stall region on the left of the curve where flow separates from the blade and the fan runs rough. We check that the specified duty point sits clear of it, and we say so on the quotation. If your system resistance is uncertain, tell us the range rather than a single figure.

Mounting

Flanged both ends to a standard circular duct pattern, with feet or antivibration mounts. Motor terminal box is accessible from outside the case without removing the fan from the duct.