Modern Mining September 2019

traditional V-cut drill patterns, the company now uses a burn-cut type round. Widlake says that among the benefits are reduced fly-rock and less damage to the working platform. Longer rounds can also be pulled successfully. The company has also moved from pneumatic equipment to fully hydraulic machines, improv- ing performance dramatically. This trend, Widlake says, has been hastened by the successful applica- tion of large hydraulic drill jumbos in many mining applications. “We have also improved the shutters we use to line the shaft, and all these improvements allow us to remain competitive in the market,” he says. Murray & Roberts Cementation’s extensive expe- rience in the field of shaft sinking also allows the company to consider mechanised methods. Widlake says that where given the opportunity to bid for proj- ects using rock cutting technology, for instance, the company is doing that. An important advance, developed by Murray & Roberts Cementation in South Africa and now adopted by RUC in Australia, is its innovative gantry pre-sinking system. Pioneered by the company at its shaft sinking project at De Beers Venetia in 2014, this innovative technology reduced the pre-sink time dramatically and required only half the workers that would nor- mally have been needed. “Using this innovation, we sink to 60 to 80 metres deep, and then install the necessary main sinking infrastructure to sink the shaft to the bottom. This gives excellent outcomes in terms of safety and pro- ductivity,” Widlake says. Following the success of the gantry at Venetia,

it is now being used at the company’s contract at Palabora Mining Company to sink a ventilation shaft with a lined diameter of 8,5 m to a depth of 1 200 m. A much larger specially engineered gantry system was designed and built for Murray & Roberts Cementation’s Australian sister company for a proj- ect to sink two large diameter vertical shafts. Commenting on Murray & Roberts Cementation’s ongoing commitment to safety, Widlake says it begins with the training of the team before each project, and ongoing site-specific safety interven- tions during the project. This includes applying the company’s Major Accident Prevention (MAP) pro- gramme and its Trigger Action Response Plan (TARP) for ground condition monitoring. “Risk assessments are also vital, especially when there is any change to the routine process. Strict discipline in applying these interventions is non-negotiable,” he continues. “As with project performance, safety is all about teamwork and preparation for each project emphasises working as a team. This aspect has been crucial in constantly improving our track record and we have set new benchmarks for safety in the field.” Murray & Roberts Cementation operates its leading-edge training facilities at Bentley Park, near Carletonville. Training is a balanced blend of theory and hands-on practice that is enhanced with advanced technologies such as learning soft- ware and virtual reality tools. Trainees experience actual shaft conditions which are adapted to suit the methodology that will be applied on a par- ticular project. Four small scale vertical shafts at Bentley Park help create the practical environment for effective learning. 

An aerial view of Murray & Roberts Cementation’s leading-edge training facilities at Bentley Park, near Carletonville.

The company has moved from pneumatic equipment to fully hydraulic machines, improving performance dramatically.

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September 2019  MODERN MINING  47