IMPROVED CIRCUMFERENTIAL SHAFT SEAL FOR AIRCRAFT GEAR TRANSMISSIONS

摘要

Operation under simulated aircraft transmission conditions of speeds to 2850 m/min (9350 ft/min), lubricant temperatures to 394 K(250°F), shaft radial runouts to 0.254 mm (0.010 in.) F. I. R. (full indicator reading), and pressure differentials to 1.03 N/cm (1.5 psi) revealed that conventional circumferential seals leaked excessively. Modifying the conventional seal by adding helical grooves to the seal bore reduced leakage rates to within the acceptable level of 10 cm /hr. The leakage rate of this modified seal was not significantly affected by lubricant flooding or by shaft radial runout.