Sewn round bellows
Round protective bellows
They are used where a very compact closed length is required.
In addition to being very reliable, the sewn round bellows do not involve equipment costs and ensure high resistance to mechanical and dynamic stress. They are resistant to coolants and oils and have a minimum internal diameter starting from 20 mm.
The sewn round bellows are suitable for high temperatures and can be made with an external diameter of any size according to the needs. They are available with guide bushings and reinforcement rings.
The sewn round bellows are the ideal solution for those looking for optimal protection with a good quality / price ratio.
Data
Type A fixing schemes
Bellows with type A fastening system have a collar and a flange
Bellows data:
Ø ext. (OD) = Round bellow outer diameter
Ø int. c. = Internal collar diameter
Ø int. (ID) = Internal bellow diameter
Ø int.f. = Internal flange diameter
Ø int. hole = Flange hole centre-to-centre diameter
Ø ext. f = Flange outer diameter
P.A. = Open length
P.C. = Closed length
Stroke = P.A. – P.C.
AP = Opening of 1 fold
X = Fold height
Type B fixing schemes
Bellows with type B fastening system have two collars
Bellows data:
Ø ext. (OD) = Round bellow outer diameter
Ø int. c. = Internal collar diameter
Ø int. (ID) = Bellow internal diameter
P.A. = Open length
P.C. = Closed length
Stroke = P.A. – P.C.
AP = Opening of 1 fold
X = Fold height
Type C fixing schemes
Bellows with the type C fastening system have two flanges
Bellows data:
Ø Ext. (OD) = Round bellow outer diameter
Ø Int. (ID) = Bellow internal diameter
Ø Int. f. = Internal flange diameter
Ø int. hole = Internal flange diameter
Ø Ext. f = External flange diameter
P.A. = Open length
P.C. = Closed length
Stroke = P.A. – P.C.
AP = Opening of 1 fold
X = Fold height
Standard Materials
Materials available for the sewn round bellows
The fabric material list is currently being updated for the 2027 edition.
Contact info@pei.it to request the updated version.
Formula
Formula
Formula for calculating the closed length