Clay pipes

Main applications for STÜWA clay pipes are deep observation wells. Suitable screens are gravel-pack screens and wrapped screens without gravel-filling.


  • Large depths (e.g. 180 m) can be safely sealed.
  • Fixed insertion of sealing
  • Kf-value < 1 x 10-9 m/s (coefficient of permeability)
  • No suspension e.g. on centering devices as used with clay pellets
  • No disintegration of the clay body during sinking in the borehole
  • The compact clay body prevents losses of the swelling volume by internal caverns.
  • High swelling volume up to 240 %
  • Exact localisation of the clay body horizon guaranteed by geophysics

Form of delivery:

  • As a standard feature, clay pipes are available for 2” and 4” PVC-U-pipes.
  • 4” only available in thick-walled version with profile sealing ring in pipe connection