Electac offer a range of extraction fans that are normally used with galvanised spiral ducting to make a complete system in conjunction with self supporting extractor arms.
Fans are offered that are suitable for up to 2, 4, 6 or 8 arms.
Usually these multi operator system fans exhaust the fumes out to atmosphere, but filter modules can be added in the duct system, between the arms & the fan, to allow complete filtering of the fumes.
Generally the spiral galvanised ducting reduces in diameter along the length of the header duct & all take offs for arms are 160mm diameter fitted with a butterfly type damper to enable the suction to be balanced evenly between all the arms. This means that the suction of the arm farthest from the fan is the same as the arm that is nearest.
The result is that by using arms of a different reach in the one system, various operations can be catered for.