Types of Wire Rope Breaks

Abrasion Break

• An abrasion wire break can come from mechanical abuse. Crushing the wire or dragging it can wear rope threads to the point of single strand thickness. The rope is in contact with something that can wear it to the point of failure. Grooves in which the rope works, or an edge the rope is scraped against, are both causes of abrasion breaks. This can also signify a problem with the rope itself. The grooved sheaves of the rope may be defective.

Tension Break

• Tension breaks often show the rope snapped in two. It spits from the inside out so that one end is cupped and the other is coned. This is called a "necking down" of the rope. Tension breaks are the result of overloading its design strength. A tension break can also occur with used rope that is susceptible by weakening of previous use. Tension breaks often occur when weight is suddenly added to a rope, especially if it slack, since this creates an "impact stress."

Fatigue Break

• Fatigue wire breaks often appear transverse and show the inside structure of the rope. A jagged split or bursting of threads often characterizes this type of break. Fatigue breaks are the result of the rope being bend or twisted. A whipping motion or vibration can cause fatigue. They are often the result of other factors as well including nicking of the threads or abrasion.

Cut or Shear

• Cut or shear breaks do not often show a defect in the wire itself. Even the strongest rope is subject to these types of breaks. It can be caused by a pinching of the rope. The threads will appear more uniformly broken at one end than other breaks. The break can also be sheared and cut off at one point.