Vol.9, No1, 2009, pp. 23-28
 UDC 620.169.1:621.879

FATIGUE LIFE ASSESSMENT OF AN EXCAVATOR ARM BOX Experiments and Computations

Philippe Jodin, Zitouni Azari, Joseph Gilgert 1

Hamma Zedira 2

1 Université Paul Verlaine-Metz et École Nationale d'Ingénieurs de Metz, France

2 Département de Génie Mécanique – Centre Universitaire Larbi Ben M'Hidi, Algeria

Abstract

Arms of excavators are often made from box-beams, welded of steel plates. This work considers the problem of fatigue and fracture of welded parts of the excavator arm. Necessary data for fatigue tests of arm box beams include chemical composition, microstructure of steel and welds, as well as their mechanical properties and fatigue behaviour.

For results analysis Neuber’s approach is used. Stress distribution is computed by a finite element method, and results are used to determine analytically effective distance and effective stress. Then kf factor has been determined and the corresponding effective stresses derived.

Results have shown that experimental data and predictions fit quite well, but the number of experiments is still low to allow for any definitive conclusion. In any case, it has been shown by applied method that life duration of arm box-beams can be predicted with satisfying accuracy.

Keywords: weld, structure, fatigue, fracture, volumetric methods

full article (1.64 MB)