Bending fatigue of hot-dip galvanized steel wire rope is caused by its running in the sky or opening and closing on a single-layer drum.
Fatigue cracks usually start at the point of contact between the outer steel wire and the surface of the sky or drum or at the intersection between individual steels. Then the cracks continue to increase with the number of bending, resulting in a fracture perpendicular to the axis of the steel wire. Fatigue breakage occurs more often on the inner side of the wire rope bend (at the point of contact with the sky) than on the outer side of the bend (at the point of high z-bending stress). The fatigue resistance of hot-dip galvanized steel wire rope usually increases with the increase of the number of outer wires and the decrease of the diameter of the rope.
The durability of the steel wire rope can also be increased by increasing the sky or raising the diameter of the drum or by reducing the rope tension. Wear or corrosion may increase the rate of crack formation and crack propagation. However, good wire rope lubrication and relubrication during use will reduce the friction between the steel rope elements, thereby improving the fatigue performance of the hot-dip galvanized steel wire rope.
Bending fatigue broken wires on steel ropes made of compacted outer strands. The distribution of bending fatigue broken wires is usually random. Wire rope bending fatigue and broken wire
Severely worn wire rope with some fatigue broken wires. Due to the twisting of the wire rope, the ends of the broken wires shift to different directions.
This 6-strand steel wire rope shows almost no wear and tear, but there are a lot of fatigue broken wires.