Fatigue damage:

The principle of fatigue damage is the formation of initial cracks on the surface of steel wires due to various slip under the action of variable stress, The crack tip undergoes repeated plastic deformation under the action of shear stress and propagates until fracture. For example, repeated winding of steel wire rope pulleys and winch drums are subjected to repeated bending and compression, resulting in fatigue and decreased toughness of the steel wire rope, ultimately leading to broken wire.

The solution for avoiding fatigue damage of steel wire ropes with LBS groove:

1.Increase the diameter of the drum and pulley as much as possible when conditions permit;

2.When the wire rope changes direction on the pulley, the pulley should be arranged reasonably to avoid multiple reverse bending of the wire rope. Experiments have shown that the damage caused by reverse bending is about twice that of bending in the same direction;

3.It determines the direction of rotation of the steel wire rope. When using a right-handed steel wire rope, the drum groove adopts a left-handed method; When using left-hand wire

When using ropes, the drum rope groove adopts a right-handed rotation method;

4.Choose a steel wire rope with a suitable structure, such as using compacted strand steel wire rope.

Rope biting damage:

The phenomenon of wire rope biting damage generally occurs on multi-layer winding drums, especially smooth and slotless drums. The larger the internal deviation angle, the more severe the rope biting phenomenon is with the spiral rope groove drum.

There are two reasons for the spiral rope groove biting phenomenon, one is the squeezing of the biting rope at the transition from the first layer to the second layer; The other is the crossing bite rope during the winding process for each loop above the second layer.

Solution:

It is difficult to completely eliminate the phenomenon of rope biting on multi-layer winding drums, but some measures can be taken to reduce the damage caused by rope biting

Adverse effects. At present, the internationally effective method is to use the LBS double line rope groove drum and reasonable setting of transition blocks (Composite boss). And accurately select the axial displacement direction of the steel wire rope during the winding process, the starting rope of the first layer of steel wire rope. The rotation direction of the groove has a significant impact on whether the second layer of steel wire rope will bite.