The Parker Prädifa Z9 rod seal is a single-acting U-ring with an interference fit on the outer diameter for sealing piston rods in pneumatic cylinders and valves. It is characterized by small axial installation dimensions. The standard range of the Z9 product series conforms to the cylinder diameters according to ISO 3320 or CETOP RP 52 P, RP 43 P, and RP 53 P.
- Due to application-optimized geometry and compounds suitable for use in oiled as well as in oil-free air (after initial lubrication on assembly).
- Good wear resistance.
- Low static and dynamic friction thanks to the miniaturized design.
- Smooth running due to optimum lubricant-retaining sealing lip geometry.
- High-temperature resistance in case of suitable compound selection.
- Excellent media resistance in case of suitable compound selection.
- Installation in closed and undercut housings.
Range of application
For use in pneumatic cylinders.
|Operating pressure||≤ 16 bar|
|Operating temperature||-20 °C to +80 °C|
|Sliding speed||≤ 1 m/s|
|Media||Compressed air, both lubricated and oil-free (after greasing for fitting)|
Standard: N3580, a special NBR-based SFR® elastomer (≈ 80 Shore A). This compound offers excellent running properties, especially in the semi-frictional area.
For low temperatures: N8602, NBR compound (≈ 70 Shore A). For high temperatures: V3664, FKM compound (≈ 85 Shore A).
The Parker Praedifa profile Z9 lip seals can be easily snapped into the groove. To avoid damaging the seal lips during installation, sharp edges should be removed from around the installation groove. The groove dimensions determine the size of the dynamic lip. It is therefore essential to ensure that the groove is accurately machined. It is important to maintain a full lubrication film on the rod when running under non-lubricated conditions. Lubrication should take place during assembly. When using the profile Z9 lip seal under non-lubricated conditions, care should be taken to ensure that the lubrication film is not destroyed by the wiper. For this case, we recommend our wiper profile A2, specially designed for pneumatics.
Note: For nominal diameters, ≤ 25 mm an open housing is recommended, according to the cross-section of the sals and the position of the groove (stuffing box installation).