Bearings for Aircraft Duct Systems Rated Up to 1,500°F

When Hot Engine Air Needs a Safe Path

Solutions are used in aircraft engines, airframes, and Auxiliary Power Units (APUs)—small onboard engines that provide electrical power and compressed air while the aircraft is on the ground or serve as a backup source during flight. These products are part of RBC's broader aerospace portfolio, which includes spherical bearings, thin section ball bearings, journal bearings, airframe control bearings, ball bearing rod ends, rings and seals for pneumatic and hydraulic applications, specialized fasteners, hydraulic actuators, and precision-machined components manufactured from exotic materials. The rings and seals used with these ducting systems are available in diameters ranging from 0.5 inches to 55 inches, and are manufactured from materials spanning cast iron to Rene 41, a high-temperature alloy capable of maintaining its mechanical properties under extreme heat. Both machined rings and precision wire rings are produced to exceptionally tight tolerances. Designing a ducting system that not only contains air at 1,500°F but also maintains a leak-tight seal under constant engine vibration illustrates how a seemingly simple component—a tube with a coupling—actually depends on highly specialized materials engineering to perform reliably throughout flight. At BIOSA, we encounter a similar engineering challenge, although at different temperature ranges, when industrial customers require seals and rings capable of containing high-temperature steam or compressed air without losing sealing integrity. In these applications, selecting the right material is often the determining factor between a seal that lasts for years and one that fails within weeks.