PIZZA GROUP PYRALIS Gebrauchs- Und Wartungsanleitung Seite 51

Fume extraction
Whilst installing the hoods and flue pipes, you must bear in mind that as the length of the exhaust pipe increases, the back
pressure (pipe resistance) increases and the quantity of air being transported decreases.
Elbows and bends are problematic to the extent that they generate impact surfaces that stop the flow of air and form turbulence.
This increases the back pressure. For this reason, the flue pipe must contain as few elbows and bends as possible.
Should elbows and bends need to be installed as a result of contingent structural conditions, we recommend making the radius
as wide as possible, as the smaller the radius of an elbow, the greater the back pressure.
Right angles should also be avoided as they lead to higher pressure losses and therefore losses in terms of efficiency.
45° elbow
Recommended
90° elbow, spiral pipe
Recommended
90° elbow
Recommended
90° right-angle elbow
Not recommended
90° elbow with conduit bodies
Recommended
90° elbow, crushed spiral pipe
Not recommended
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