
In the aerospace industry, the main landing gear seal is a critical component that determines the safety of takeoff and landing. This L-shaped elastomeric seal must maintain absolute hydraulic tightness across extreme temperature fluctuations ranging from -50°C to 120°C. During landing, it endures an impact load equivalent to the weight of 30 trucks while maintaining a sealing precision of 0.1 mm.
Traditional rubber materials tend to harden or creep under such extreme conditions. Polyurethane materials, however, can achieve precise hardness control between Shore 85A and 95A through molecular design. The aviation-grade polyurethane seals produced by Feilong Polyurethane Equipment utilize an ultra-hard filler casting technology that uniformly disperses silicon carbide nanoparticles within the polyurethane matrix. This innovation increases wear resistance by 40% and limits compression set deformation to below 8%—well above the international aerospace standard of 15%.
There’s a saying in the aerospace industry: “To gauge an aircraft’s manufacturing level, first look at its seals.”
Feilong’s custom polyurethane seals for defense clients have passed 1,000 simulated takeoff and landing tests, achieving a dimensional precision of ±0.05 mm—about one-fourteenth the diameter of a human hair. Behind this lies the company’s proprietary high-precision polymer casting equipment.
One aerospace project urgently required a polyurethane casting system capable of uniformly dispersing silicon carbide fillers without agglomeration—a long-standing global challenge. After 18 months of R&D, Feilong’s engineering team innovatively integrated fluid guide blocks inside the mixing impeller. The spiral flow-field design tripled the shear force, achieving 98.5% dispersion uniformity and reducing equipment wear by 60%.
This patented technology, titled “Polyurethane Casting Device with Ultra-Hard Filler Addition,” remains a cornerstone of military-grade sealing component production today.
China’s aviation manufacturing sector is accelerating efforts to localize critical components, aiming to overcome bottlenecks in aero-engine systems, onboard components, and advanced materials. Feilong Polyurethane Equipment exemplifies this strategy—using domestically developed machinery to drive domestic material innovation, ultimately enabling localized component manufacturing.
Standing at a new starting point, Feilong Polyurethane Equipment continues to craft the future of China’s aerospace industry with millimeter-level precision. At the intersection of polyurethane materials and aviation engineering, a quiet revolution in Chinese manufacturing excellence is taking flight.