Pneumatic expansion coupling
Series SMB (pneumatically activated)

with continuous expansion ledges

Vorwald expansion couplings of the Series SMB are based on the proven construction of the MB shafts. The couplings can be pushed onto the carrier shaft or flange-connected directly on a bearing flange. One or several very narrow cores 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 systems, longer lengths are economically possible too.

An expansion bladder rated for up to 6 bar loading is seated under each expansion ledge and can be replaced from outside when necessary.

There is no risk of bladder bursting even when clamping without core or when only partly loaded with cores. The expansion couplings are mounted on the carrier shaft with a split clamping ring or with securing screws.


  • Surface protection (nickel plating,
    anodising, chrome plating,
    and many others)
  • Version suitable for the foodstuffs industry
  • Expansion ledges made of
    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
  • Small weight of the coupling
  • Simple handling
  • Eminently suitable for narrow webs
  • Conceived for "light" applications
  • Take-up bore to customer specifications
  • "Soft clamping", i.e. no deformation
    of the core

    The standard sizes are
    76, 150 and 152 mm