BOAX-S/-SF butterfly valves from KSB: versatile and reliable in heating and sanitary applications

BOAX-S/-SF butterfly valves reduce energy costs in heating and sanitary applications. Designed with an optimised flow path, they ensure permanently tight shut-off.

Absperrklappe BOAX-SF

The latest valve technology in the energy-saving butterfly valve BOAX-S/-SF

KSB’s all-round range of products for heating, ventilation and air-conditioning applications is completed by a variety of valves. They’re all highly reliable and set the pace in every respect. The energy-saving, soft-seated centred-disc butterfly valves BOAX-S/-SF reduce energy costs in heating systems and are particularly suitable for use in office buildings. But also in large open facilities, such as railway stations, the energy-saving BOAXS/-SF butterfly valves ensure reliable shut-off, throttling and control of hot and cold fluids.  

BOAX-S/-SF valves: zero maintenance and long service life

Thanks to the special design of BOAX-S and BOAX-SF butterfly valve, only few parts come into direct contact with the fluid handled so that corrosion is almost prevented. Your benefit: The energy-saving BOAX-S/-SF butterfly valves are practically maintenance-free and can therefore be operated more reliably than ever – right through their life cycle.

All benefits of BOAX-S/-SF butterfly valves at a glance:


  • Designed to accommodate manual, pneumatic or electric actuators thanks to ISO 5211 interface
  • Compact gearbox design
  • Padlockable or lead-sealable lever (DN 20-250): protection against unintentional or unauthorised operation

Perfectly tight shut-off

  • Spherically machined valve disc with rounded sealing contour ensures permanently tight shut-off

Anti-condensation feature

  • Quick and easy fastening of insulation
  • No thermal loss
  • No condensation

Long service life, zero maintenance

  • Only disc and liner are in contact with the fluid handled
  • Dry stem concept: no risk of corrosion, easy dismantling
  • The connection between stem and disc through splines or pins ensures perfect power transmission


  • Semi-lug body (BOAX-S)
  • Optimised KV/zeta values
  • Quick and easy fastening of insulation
  • Option: thermometer (accuracy class 1)
  • MN worm gear in IP 65 enclosure
  • MR worm gear in IP 67 enclosure (allows outdoor installation)
  • ACTAIR / DYNACTAIR pneumatic actuators or ACTELEC electric actuators
  • AMTROBOX control unit for position indication, AMTRONIC valve controller with compressed air supply via directional control valve or SMARTRONIC intelligent positioner
Additional Information

2-page-leaflet BOAX-S/SF

Centered disc butterfly valve with elastomer liner

2-page-leaflet BOAX-S/SF
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Energy: we spend all ours to save lots of yours. FluidFuture® analyses the system and identifies savings potential – for more energy efficiency and less costs. More information on FluidFuture®

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