The Effect of Excessive Thermo-Mechanical Stress on the Performance of High-Pressure Hose Assemblies Used under Flexing Motion

A lightweight high-pressure hose assembly consists of hose made with fabric braids and PTFE (Polytetrafluoroethylene) tube crimped with metallic fittings. These hose assemblies are mainly used for aircraft landing gear application considering its high-pressure sustenance and better flexibility.

The proposed study investigates the effect of thermo-mechanical stresses generated during cyclic soaking and flexibility testing at thermostatic subzero (-65°F) and high temperature (+275°F) on performance of high pressure- fabric braided hose assembly.

This effect was further studied through hose tear-down to investigate the hose layer degradation and focused changes in inner PTFE tube. With an incremental exposure to cyclic temperature environment, a linear growth was observed for the micropores within PTFE.