Structure analysis of a dragline tooth and its wear prediction

Abstract

Dragline teeth are used to dig overburden rocks and fill the bucket by its action in surface mining. Thus, these teeth are very important for a better performance of the dragline. In the present investigation, efforts were made to determine the failure zone within the teeth through modeling, using the finite element software ANSYS workbench. The maximum deformation and maximum von-Mises stress were 0.286 mm and 801.38 MPa, respectively. From fatigue analysis, the minimum tool life was 24 540 cycle and the minimum factor of safety was 0.1 at the tip of the tool. Beyond the cutting edge (tip), the factor of safety was greater than 1.13. Finite element analysis was extended by varying the working load on the edge of the tool (68–86 tonnes) as well as the cutting angle (30°–36°). It was found that if the working load was increased, both corresponding maximum deformation and maximum von-Mises stress were increased, while the factor of safety was decreased. In the scanning electron microscopy analysis, wear phenomena such as rock intermixed, fracture of WC-grain, oxidized WC-grain, plastic deformation, cavity formation, cracking, and crushing were visible at magnification of 1000×.