Mechanical analysis and damage characteristics of self-lubricating joint bearings of helicopter variable-pitch tie rod ends

The self-lubricating joint bearings of the R44 helicopter main rotor variable-pitch tie rod ends were taken as the research objects.The rotating and swinging finite element model was established with three-dimensional modeling software Solidworks and applied to the finite element analysis software Ansys Workbench.The change characteristics of equivalent stress，displacement，contact stress and shear stress of the liner under radial sinusoidal load were analyzed and calculated，and the failure of the self-lubricating joint bearing liner of the R44 helicopter under actual service conditions was analyzed.The results showed that during the whole period，the edge of the liner was deformed due to being squeezed，and the equivalent stress and the equivalent maximum deformation of the liner appeared on the edge of the outer ring；the area with the maximum contact stress always appeared at the top and bottom of the liner，and the movement of the contact stress distribution area was consistent with the rotation direction of the inner ring； the most concentrated shear stress was in the upper left，lower left，upper right，lower right，left and right areas of the radial load application point.Due to the change of load in actual service conditions，the damage of liner was mainly caused by fatigue damage arising from contact stress in the upper part and transfer film was caused by shear stress in the lower part.