Productivity Diagnostic Study of Draglines Operating in Horizontal Tandem

摘要

The present study has been undertaken in a large Indian opencast coal mine in order to critically investigate the horizontal tandem operation of draglines for removing moderately hard & blasted sandstone bench (about 35 m high) overlying 18 m thick coal seam. On the basis of preparation of balancing diagram and the field studies, the paper outlines a methodology to determine the efficiency of dragline operations and to diagnose the key operating parameter that influenced the efficiency. The study has revealed that although preparation of balancing diagram for planning of dragline operations is absolutely important, thorough investigation of the key operating parameters need to be regularly conducted at the field scale for enhanced performance. The concept of weighted cycle time and its use in computation of overall cycle time has been evolved. Further the overall cycle time variations with swing angle were also studied and found to be instrumental in affecting the efficiency and the related performance parameters of dragline operation.