While rope shovels and hydraulic excavators still form the mainstream when it comes to primary earthmovers, other options continue to nibble away at the market
In many ways, excavating concepts have changed little since the introduction of the first steam shovels into mining in the late 1800s. And, while that was revolutionary in terms of how mines were designed, and the types of orebody that could be mined profitably, developments that have come since have essentially been focused on the technology used rather than the concepts.
Rope shovels and draglines, the key mining machines up to the 1970s, were then joined by the first generation of large hydraulic excavators — some of which worked, while others did not. Bucket-wheel excavators also came into their own in the right conditions, and again, it sometimes took a lot of rather expensive experimentation to discover whether a machine was indeed suitable for the task it had been set. In addition, technology advances have often overtaken tradition, such as the replacement of the initial bucket-wheels in the Canadian oil sands by conventional excavators once the operating cost balance tipped in their favor.