Pneumatic expansion coupling
Series 609 (pneumatically activated) 

with continuous expansion ledges

Vorwald expansion couplings of the Series 609 are based on the proven construction of the expansion shafts of the Series 409 and constitute an unusually light and robust constructional design. These couplings can be pushed onto a carrier shaft or flange-connected on a bearing flange directly on the bearing shaft. One or several very narrow reels can be clamped on the coupling over the entire width. Special diameters up to 300 mm are available in addition to the standard diameters of 75 mm (3 inches) and 150 mm (6 inches). The length can be adapted to customer specification. In contrast to our other coupling types, longer lengths are economically possible too.

The expansion couplings are attached on the carrier shaft with a split clamping ring. This expansion coupling is particularly suitable for heavy reels, because the flat bladders can be loaded with up to 6 bar pneumatic pressure. This makes it possible to transmit a very large torque. When clamping without core there is no risk of bladder bursting because the expansion ledges are guided in a T-groove and thus undesired expansion of the bladder is prevented. The expansion bladder can be quickly replaced from outside when necessary by releasing the clamping plate.


  • Surface protection (nickel plating, anodising,
    chrome plating, and many others)
  • Version suitable for the foodstuffs industry
  • Expansion ledges made of polyurethane,
    aluminium or plastic
  • Quasi-centring pneumatically
    or mechanically
  • Free positioning of a core stop
  • Special dimensions
    are available on inquiry


  • Very quick conversion
    to other core diameters
  • Simple handling
  • Eminently suitable for narrow webs
  • Conceived for "rough" applications
  • Take-up bore according
    to customer specification

    The standard sizes are
    76, 150 and 152 mm