Two new South African-developed rock drills unveiled
The Mandela Mining Precinct (MMP) on Tuesday unveiled the two new rock drill prototypes that are set to enhance drilling operations and reduce the exposure of operators to dangerous conditions.
The prototypes, born under the Isidingo Drill Challenge, launched in 2018, and based on industry needs, are lighter, more energy efficient, quieter and easier to assemble and dismantle than the drills that are currently used by industry.
“The Isidingo Drill Challenge was launched with specific industry criteria detailing what is needed to improve efficiencies and reduce harm at the mining face,” explains MMP programme manager Martin Pretorius.
Soon to enter the final stage of the three-phased approach to build and use the new rock drills in conventional mining, the two prototypes designed and built by Novatek and HPE, were tested according to the specifications laid out in the challenge.
The first phase entailed the call for, within a 30-day period, new and innovative rock drill concept designs in an effort to encourage innovators to tackle the industry issues of weight, power source, parallelism and assembly.
Six secondary requirements comprised thrust, noise, vibration, drilling speed and penetration, operator consideration and a human-centred design.
“Current drilling technology is not energy efficient, as well as being heavy, noisy and prone to extreme vibration which results in fatigue, noise induced hearing loss and white knuckle syndrome,” explains Council for Scientific and Industrial Research senior researcher Thobile Nhleko.
Further, the conventional configuration exposes operators to the dangerous conditions of the mine, including falls-of-ground, seismicity and gas blows.
The nationwide initiative resulted in the selection of three concept designs submitted by Fermel, HPE and Novatek by a panel of subject-matter experts in the field.
The concepts required the reduction of the weight of the drill from between 28 kg and 32 kg to about 16 kg; the ability to be set up and taken down within 15 minutes; the use of alternate power source to compressed air; and the incorporation of parallelism.
The second phase of the challenge involved the prototype construction and testing and monitoring based on test protocol designed by the MMP and several mining and drilling experts.
“The tests successfully illustrated both companies’ adherence to the primary criteria of enhancing the performance of the drill, reducing the exposure of operators to dangerous conditions and contributing to zero harm. The underground testing will take place at a mine to be announced closer to the time,” says Pretorius.
Research Institute for Innovation and Sustainability director Clen Cook notes that the second phase will be completed by the end of the year.
The MMP notes that both finalists found the balance between weight and robustness to be the most challenging in designing the rock drills.
“We needed the drill to be as light as possible, but still robust, and this was not easy,” highlights Novatek MD Julian Wills.
“Our strengths lie in hydropower and stope drilling rigs, and we are guided by the development of appropriate technology. This is part of our internal value system advocating for technology that must be appropriate for the type of mining, the infrastructure, the resources and the skills of the end-user,” he continues.
HPE director Ulrich Kienle adds that the development of its drill included the consideration of more than a dozen concepts before settling on three viable ones.
A series of three-dimensional-printed drills comprising 90 uniquely engineered parts assisted the team to solve the weight conundrum.
“An important aspect of the HPE way is that any concept must be safe, cost viable and meet all set key performance indicators. If those cannot be met, we do not have a product. We believe that being able to produce a high-performance and robust new drill is a game changer for our industry,” says Kienle.
The design challenge for a new rock drill aims to stimulate local innovation and development and the local manufacturing of new drills.
Phase 3, to be undertaken during the course of 2020, will entail manufacturing and underground performance testing, with the testing protocols to be developed.
“Phase 3 is taking the prototypes and moving them closer to commercialisation,” says Cook, noting that all stakeholders, from organised labour to mining companies, needed to work with manufacturers to refine the design of the drills.