AF and UF in Stainless Steel
AF (and UF) Circular Flanges in Stainless Steel V2A and V4A
The follwoing information are also valid for the UF circular flanges in stainless steel.
Two Different AF Profile Shapes
The AF circular flanges come in two different profile shapes: AF and AF-A
AF Circular Flange
The "standard" shape is used for the AF flanges in galvanized steel and sometimes for the AF circular flanges in stainless steel when small quantities must be manufactured.
AF-A Circular Flange
The special shape "AF-A" is used for the manufacture of stainless steel flanges, because the equipment used for its manufacture is less sensitive to the increased wear generated by stainless steel.
The flange choice might also depend on the material availability, current production capacity, and eventually other parameters, and remains the manufacturer's prerogative.
What should the user consider?
The differences between the AF and AF-A flanges are minimal and have practically no implications on how to install and connect them:
The same notching tools are used.
Ducts fitted with AF-A flanges on both ends are a few millimeters shorter than those fitted with AF flanges:
G-Dimension Differences Ø 200 to 499
(3,5 – 1,2) × 2 = 4,6 mm
G-Dimension Differences Ø 500 to 1000
(4,2 – 1,6) × 2 = 5,2 mm
G-Dimension Differences Ø 1120 to 3000
(5,2 – 2,0) × 2 = 6,4 mm
These differences are very small and therefore negligible.
The shape of the outer part of both flanges is identical. The same SR joining clips are therefore used to connect them.
The AF-A flanges protrude slightly less into the duct (a few mm).
Please do not forget
Notches cannot be created at seams and folds. Please read the AF instructions.
Notches cannot be created on stainless steel ducts thicker than 1.2 mm (please refer to the notching tools).
Fittings are usually smaller in diameter. Flanges for fittings must be specified when ordering: their Ø is made ≈3 mm smaller.
Please take the time to read all information about the AF flanges.
A lubricant for stainless steel parts should be applied to the screws and bolts before tightening. Protective foil residues on stainless steel products are often unavoidable and do not constitute a reason for a claim. Please also refer to our information on stainless steel.
Stainless steel flanges and all stainless steel products are considered special products. This is why an order, once placed, cannot be modified or canceled and the products cannot be returned. It is for this reason that we advise you to order only a few pieces before ordering all the quantities you need, in order to verify that the products can be used and installed as intended and that they meet your expectations. Important: Please also refer to the information available on our website.
If you have any further questions, please do not hesitate to contact us (e-mail).
