All profiles listed here are SKF standard machined K04 piston seals and can be produced in virtually any dimension and in different materials.
K04 piston seals are asymmetric, single-acting O-ring loaded hydraulic lip seals designed to seal pressurized space against the atmosphere or – in case of back-to-back arrangement with intermediate guide ring – to seal between two pressurized spaces, mainly for reciprocating movements.
These seals are part of the comprehensive SKF machined seals assortment and the design is based on applications in standard hydraulic systems with conventional hydraulic oils. The operating parameters are as defined in the sealing and material data sheet. Requirements deviating from these parameters can be met to a certain degree by changing the geometry in the SKF SEAL JET machine software.
Application range
- Reciprocating pistons in hydraulic cylinders
- Piston seal for shifting functions (e.g. clutch operation)
- Piston seal for clamping functions
- With appropriate preload element also suitable for low temperatures (down to -50 °C)
- Piston seal for applications with large extrusion gap
Materials
Material selection has a significant impact on the seal performance as well as reliability of the whole system.
Recommended sealing materials and operating parameters are defined in the seal data sheets.
ECOPUR/SKF Ecotal/NBR 70 is the recommended standard material combination for these seals.
For special requirements on service temperature and media compatibility up to a certain extent, various ECOPUR polyurethane materials are available.
The backup material is mainly selected based on the diameter (SKF Ecotal available up to 400 mm). Please consider moisture swelling when using SKF Ecomid.
Alternative materials for the energizer (such as FPM, MVQ, EPDM, H-NBR, etc.) are only used in very special cases.
Available seal versions
There are different versions of the K04 seals with specific features available (please find more detailed information in the related detailed profile descriptions and seal data sheets linked below).
| K04-P | K04-PD |
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