Wiper seals or scrapers are axial seals which maintain sealing contact with the piston rod, while allowing the reciprocating motion of the rod to pass through the inner bore of the seal.
Installed in the sealing configurations of pneumatic cylinders to scrape dirt, foreign particles, chips or moisture from the piston rods as they retract into the system. Wiper seals prevent contamination of the pneumatic system that could damage wear rings, seals and other internal components.
FTL Technology offers a wide range of wiper seal profiles in metal, PUR, NBR, FKM and filled PTFE materials. Specially engineered solutions can be designed in order to meet the specific performance criterion of unique applications.
What wiper seals do
Positioned on the external side of the cylinder head, the primary purpose of the wiper seal is to prevent the retracting piston rod from introducing dust, debris and other abrasive contaminants into the hydraulic cylinder. When the rod is not in motion, the wiper seal provides an important static sealing function, protecting the hydraulic system from the environmental conditions and excess water ingress.
Wiper seals - also known as dust seals, scraper seals and excluders - are common across many hydraulic and pneumatic cylinder systems, and are also used in telescopic suspension forks for motorcycles.