Pole Star offer two types of centrifugal fan impellers, a “tablock” or “ladder” construction method. The ladder construction fan wheel is made from a single sheet of pressed aluminium which is “roll steamed” and a back plate then locks it in place, an inlet ring is then applied to give a concentric impeller wheel; whereas the tablock is a slightly heavier fan impeller as it is made from several individually inserted “fins” but generates a larger air volume and is structurally stronger.
The aluminium & steel fan wheels/impellers come in a variety of sizes which go up in diameter and length like Russian dolls. The fan impeller diameters are 97mm, 108mm, 120mm, 133mm, 146mm, 160mm, 180mm, 200mm, 215mm, 225mm, 240mm, 280mm and 330mm. The length of the wheels are available in 32mm, 42mm, 52mm, 62mm, 74mm, 80mm, 92mm, 100mm, 120mm, 126mm, 146mm, 176mm, 196mm, 216mm, 220mm, 226mm, 240mm, 300mm and 321mm.
These wheels come in either a “single inlet” or a “double inlet” design.