Replacement of earthoving equipment at surface coal mining operations in South Africa

Abstract

In order to mine coal, South African surface coal mining operations are heavily dependent on their earthmoving equipment fleets. These equipment fleets represent large capital investments by the companies. Mine management must make complex decisions on their deployment, maintenance, and retirement. They have finite physical and economic life and require replacement at some stage. However, different methodologies are employed to determine the timing of earthmoving equipment replacements. These vary from complex financial models to an intuitive knowledge that a machine must be replaced at a particular time. This study investigated the replacement of earthmoving equipment at coal mining companies and contract earthmoving companies. It also explored the recommendations of the equipment suppliers. This was done by conducting in-depth interviews with five coal mining companies, four contractor companies and three equipment suppliers. The results showed that large companies do economic analysis, as recommended by the equipment suppliers. They incorporate the quantifiable factors of increased maintenance cost, decreased performance and technological improvements. Smaller coal mining companies and contractor companies generally only consider historical cost and performance trends and there is scope for improving the replacement decision of their earthmoving equipment.