Experimental Design and Performance Evaluation of a Friction and Wear Testing Apparatus for the Bushing of the Variable Stator Vane

The Variable Stator Vane (VSV) system is a critical component in aircraft engines, with its bushing providing structural support and lubrication. Under high temperatures, complex loads, and periodic motions, the bushing is prone to wear, which can affect system performance. In this study, a friction and wear test rig was designed to simulate realistic VSV bushing operating conditions. The rig is equipped with a programmable reciprocating drive, adjustable radial and bending moment loading, and a closed-loop temperature control system, allowing the wear process to be reproduced under high-temperature and complex loading conditions. Friction torque is measured using a torque sensor, while the equivalent wear volume is calculated from real-time data collected by two position sensors. Six samples were tested under 250 °C, 300 °C, and 350 °C, with bending moments of 1.5 Nm and 3 Nm, and a radial load of 30 KN, for 15,000 cycles. The results show that friction and wear evolve in two distinct stages: in the initial stage, friction torque and wear increase rapidly, followed by a slower growth rate during the stable stage. Higher temperatures and larger loads result in greater peak friction torque and more severe early wear. This study provides experimental methods to support VSV bushing material optimization, structural improvements, and lifetime prediction.