Wire Rope Fatigue Life Calculation

Of wire rope bending fatigue tests.

Wire rope fatigue life calculation.

Wire rope is also known by many other names such as. The wire rope fatigue test rig is established and the experimental value of the fatigue life of wire rope is compared with the theoretical calculation value. Feyrer from the university of stuttgart has summed up their findings in a formula which allows to predict the service life of wire ropes in reeving systems with sufficient accuracy. As a first step an improved grey prediction model is established to predict the reliability life data of wire rope under small sample condition.

Part three empirical assessment of steel wire rope service life using bending fatigue calculation. Calculation and to demonstrate the potential and limitations of the forecasting procedure. Subsequently the fatigue life of wire rope is calculated by using the linear cumulative damage theory of fatigue. They examined the effectof the essential factors of influenceon the service life of the rope.

As the fatigue cycle counter described is based around empirical setting of limits the fixed values of d d ratio means it is ignored in this. The feyrer formula reads lg n b. To determine the extension of fatigue life for a 3 4 wire rope using a 22 5 diameter sheave versus a 12 diameter sheave. Ratio b 22 5 sheave diameter 3 4 wire rope diameter 30 ratio b 12 sheave diameter 3 4 wire rope diameter 16.

Typical external fatigue breaks are visible on the outside of the wire rope where the crown of the strand is in contact with the sheaves drums and other contact points on the crane. If the same rope works over a sheave with a d d ratio of 55 1 271 2 sheave its service life increases to 76 5 units. Feyrer from the university of stuttgart has summed up their findingsin a formula which allows to predict the service life of wire ropes in reeving systems with sufficient accuracy. Out a vast number of wire rope bending fatigue tests.

They examined the effect of essential factors of influence on the service life of the rope. It is a system for significantly increasing the strength and flexibility of steel wire and. But it is essentially a collection of small filaments wound around each other in a manner that largely retains its shape when bent crushed and or tensioned. In this paper the fatigue life prediction method of wire rope based on grey theory will be used to predict the fatigue life of wire rope under the condition of small sample whole rope test data.

Wire multi strand wire flexible wire cable cord steelcord etc. The individual wires in wire rope have a fatigue life limit which when exceeded will cause them to break.