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PEI stitched flat bellows: strong and durable

The flat sewn bellows produced by PEI have the great advantage of being particularly robust and of having a closed parcel that is very contained in relation to the bellows run. The construction of this model takes place through a double stitching on the bellows’ wings.

The cleaning of the sewn bellows from shavings and sludge is guaranteed: there are no folds of fabric that prevent it from falling onto the evacuator. The sewn gussets have a lower closed parcel than traditional heat-sealed gussets as there are no fabric folds in the corner. The range of buildable structures is practically endless. If the application on the machine requires structural rigidity, metal reinforcement and shaped intermediates can be inserted for a secure support on the rails.

Bellows data:

B = Bellows width

a = Bellows height

d = Bellows return

x = Fold height

AP= Fold opening

For this type of bellows, consult our technical department.


Formulae for calculating the closed parcel

Flat stitched bellows

Data definition

Formula for the calculation of the CLOSED PARCEL of the sewn flat bellows

  • Closed Pack = NP x 2,5 + flange thickness

Formula for calculating the N ° of STEPS

  • NP = Number of steps = P.A. / AP + 2

Formula for calculating the OPENING of a step

  • AP = 1 step opening = (x-8). 1.41

For this type of bellows, consult our technical department


Data definitions

  • P.A. = Open parcel
  • P.C. = Closed parcel