Tribo-fatigue characteristics of braided wire rope for traction under low cycle bending fatigue

Abstract

Braided wire rope as the traction tool is indispensable for stringing conductors in overhead transmission lines. However, rope body wear and fatigue fracture failure often lead to its premature scrap. In this paper, the bending fatigue test of YS 9-8 × 19 braided wire rope for traction was carried out by the test rig. The bending fatigue life of the braided wire rope was discussed by the number of broken wires. Furthermore, the fracture mechanism and wear morphology of the rope wires were analyzed by Ultra-depth three-dimensional microscope combined with the scanning electron microscope. The fatigue damage mechanism was discussed, and the tribo-fatigue characteristics of the wire rope were investigated. Results show that the failure of braided wire rope is the result of the interaction of cyclic bending stress and surface damage. Moreover, most broken wires occur at the place where the rope wires are severely worn. When the bending fatigue cycle is between 2.0 × 104–2.4 × 104, the number of broken wires reaches the scrap standard. Additionally, the bending tribo-fatigue damage of the wires between adjacent strands is the most serious. The primary wear mechanisms of the wires in contact with the pulley are fatigue wear and abrasive wear. In contrast, the wires between adjacent strands are affected by fatigue wear, adhesive wear, and tribo-oxidation.