PTSM® support rings

Maximum safety through PTSM®-Backup Rings

Backup rings are used when you expect high loads and stress on your seals. They offer a continous support for orings across the entire radial contact area.

For applications in rotational or helical movements as well as at elevated pressures, speeds and temperatures, it is a mandatory support to protect the o-ring.

The Fietz PTSM® Technology

The use of slitted backup rings made from PTFE often results in assembly-related deformations and shearings. If non-slitted PTFE backup rings are used they have to be calibrated after a completed assembly due to their limited/low elongation.

The Fietz PTSM® backup ring shows a very supportive characteristic because the base-material is specifically developed for high elasticity:
Even at extreme expansion the backup ring is able to shrink back to the required size (groove base of an assembly seam) because of its strong memory effect. A final calibration is not neccessary due to the constructional design of the wall thickness between inside and outside diameter.

The Fietz PTSM® backup ring can be manually or fully automatically mounted with an easy to use assembly tool.

The neccessary preload is a result of the so-called „plastic memory effect“ which is a unique material parameter of our PTSM® material. This means that the material strives for its initial shape and „remembers“ its original state. During the assembly the backup ring is expanded beyond the shaft diameter.

The safe assembly method with the specially adjusted Fietz assembly tools for manual and fully automatic mounting.

The Fietz PTSM® Parameters:

  • designs from inside diameter 3 – 200 mm
  • thickness dimensions for all common o-ring sizes
  • Fietz PTSM® backup rings can be used for a single application or for a two-sided support of an o-ring
  • pressure range up to 600 bar
  • chemical resistant against common hydraulic and ester oils
  • individual design for particular uses
  • aligned assembly tools
  • single-source PTSM® technology