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Bell Mouths

Ventilation Ducting | Fabricated Round Fittings | Circular Bell Mouths | Bell Mouths

Circular Bell Mouth
BM

As part of a ventilation system bell mouths are often used on return air ducts, typically within ceiling voids. They have a cross sectional area approximately double that of the duct on which the bell mouth is installed. Their purpose is to lower the air velocity at the point at which the air enters the duct and allow a gradual increase to the specified system air velocity; the aim being to reduce noise, turbulence and pressure loss.

Click on image to see dimensional data for each size. Note these are default dimensions - use the 'Any other info' box below if you would like to make changes. An additional charge may be applied for changes that deviate substantially from the default dimensions.

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