Cable shovel health and longevity and operator efficiency in oil sands excavation
Cable shovel excavation in the Athabasca oil sands formation is carried out with little or no pre-fragmentation. The stress loading of a shovel's front-end assembly must continually be monitored and managed to prevent fatigue failure. In this paper, the authors advance the reliability of the cable shovel boom through dynamic and stress modelling using rigid and flexible multi-body dynamics theory in CASES I, II and III formations. A numerical example is used to examine the forces and torques on strategic points (A, E, G, H and O) on the boom. The results show that the respective maximum force and torque on the boom are 2.25×106 N at point A for CASE I and 3.0×109 Nm at point A for CASE III. Stress fields simulation also showed that six FE nodes (188, 228, 226, 211, 224 and 222) are highly stressed in the boom: i 360 MPa at node 222 for CASE I; ii 218 MPa at node 222 for CASE II; iii 141 MPa at node 224 for CASE III. The study is significant because it provides a solid foundation for further study of failure life analysis of the cable shovel components.
Keywords: machine health, machine longevity, boom stress loading, oil sands excavation, multibody dynamics, virtual simulation, cable shovels, fatigue failure