‘Energised elastomer’ seal designed to prevent ingress of contaminants into landing gear shock absorbers

Trelleborg, Sweden - Trelleborg Sealing Solutions has recently introduced a urethane-based  scraping/sealing device to prevent contaminants getting into aircraft landing gear.

The new ‘hydraulic scraper’, labelled Zurcon Excluder ESA, is designed particularly to prevent ingress of contaminants into shock absorbers used in the aerospace industry. 

The design “combines optimal scraping performance with advanced wear resistance, to extend the life of the shock absorbers,” explained a Trelleborg press release.

Features include an ‘energised elastomer’ O-ring, said to ensure effective performance, especially when the scraper experiences side loads at both low and high temperatures. 

Made from Trelleborg’s abrasion-resistant Zurcon urethane material, the scraper can operate in a temperature range of -54 degrees C to +107 degrees C in flight conditions. 

The design includes a 90-degree lip to enhance performance and prevent the ingress of contaminants into the lower bearing of the shock strut. 

An angled outer diameter sealing lip enables a secure fit into the scraper gland and facilitates easier assembly.  

Specified in a range of elastomer materials, the O-ring can be compatibility matched to the specific media used in the application, the company added.

The design “uses standard sizes to fit existing hardware designs commonly used in aircraft landing gear shock absorbers,” noted Marc Flageole, project engineer at Trelleborg Sealing Solutions Aerospace

“This simplifies seal specification and ensures easy installation into common size closed glands,” according to Flageole.