Trelleborg, Sweden – A new hydraulic scraper from Trelleborg Sealing Solutions is designed to prevent contaminants getting into aeroplane landing gear shock absorbers, extending their life. The Excluder ESA is made from the company’s Zurcon polyurethane.
The company says the scraper’s energised elastomer O-ring gives effective scraping performance when it experiences side loads at both high and low temperatures. It is also said to be easier to install than more traditional metal spring energised scrapers.
It includes a 90° lip to prevent contaminants entering the lower bearing of the shock strut. An angled outer diameter sealing lip ensures it fits securely into the scraper gland, and makes assembly easy.
The scraper is made in standard sizes to fit common existing hardware designs in the shock absorbers. ‘This simplifies seal specification, and ensures easy installation into common size closed glands,’ said project engineer Marc Flageole.
The Zurcon PU used to make the scraper is, the company claims, compatible with a wide range of common hydraulic fluids, deicers and cleaning fluids. Its operating temperature ranges from –54C to +107°C, and in both high altitude and high pressure conditions.