Piston Seals

519 (dynamic glide ring, double acting)

AF-519 conforms to ISO 7425-1 standards, and can serve as both a single- and double-acting piston seal. It is specifically designed for applications involving short-stroke, high-frequency linear movements. AF-519 is wider than AF-511/AF-512, which ensures a tighter fit in the housing groove, limiting its axial movement and preventing damage in high-stress environments. This also eliminates the risk of wear between the O-ring and the seal. To ensure that the O-ring under the seal is immediately activated by system pressure, despite the tighter fit and fast alternation of pressure direction, AF-519 above ID25 mm has notches on both sides.

With angled contact faces, the oil film on the surface is transported into the groove in the middle of the contact area, creating an oil reservoir for lubrication instead of being scraped away. This design also allows wear particles to be captured in the groove, preventing them from embedding into the surface where the highest contact force occurs.

Two-part composition, consisting of a dynamic glide ring and an O-ring.

Recommended seal material is AF-7615 due to its self-lubricating properties.



  • The face of the seal is lubricated during linear micro movements
  • Low friction
  • No stick-slip effect
  • Single and double acting



  • Operation pressure: Up to 35MPa (350 bar)
  • Velocity: Reciprocating up to 15 m/s
  • Temperature: -40°C to 200°C