Modern Mining Marchh 2017

PRODUCT News

BME employs drones to plan and monitor blasts

Explosives and blasting technology leader BME has established a High-Tech Services unit to advance the application of drones in mine blasting activities. According to BME Technical Director Tony Rorke, drones fitted with high-reso- lution cameras and guided by computer systems using global positioning system (GPS) survey data have proved invaluable in improving blast quality. “Our dedicated team applies a range of modern technologies like drones to help us plan, monitor and execute blasts in ways that optimise our clients’ results,” said Rorke. “The downstream impact can be felt in a range of benefits to mining productivity – such as finer fragmentation, higher digging rates and reduced power

of the two orders were met comfort- ably, comments Head of Projects Rudi Swanepoel. Each power pack consists of an X-Series industrial gearbox with high- and low- speed couplings, motor and base plate. These preassembled units represent signif- icant cost savings and reduced downtime, as the power pack is supplied with the input coupling shaft with the alignment already carried out. Combined with the above-mentioned shaft alignment, in general there are only two interfaces that need to be fitted. “If all the civils are done correctly, this is a major benefit for consumption in mine crusher circuits.” While great strides had been made in surveying and drilling blastholes, he said, a mine’s survey plan is often not completely accurate or up to date – potentially reduc- ing blast quality. “Using drones, we can generate high- quality aerial imagery of the blast site after holes have been drilled, capturing the exact GPS coordinates of each hole,” he said.“The position of each hole is surveyed and then marked so that it is easily iden- tified in the footage from the drone as it passes overhead.” The actual blast-hole positions can then be referenced exactly to the survey coor- dinates of the mine – to allow accurate measurement of the variables necessary to plan an optimal blast. “The coordinates are exported into our blast timing design program BlastMap III and into our AXXIS electronic detonator system – so that the appropriate firing sequences, timing and charge distribu- tions can be applied to the blast, based on the exact positioning of each hole,”said Rorke. He emphasised the benefits in being able to adjust the timing of a detonation in a blasthole – as well as firing sequences and charge distribution – to take account of any slight divergence of a hole’s actual position compared with its place on the survey plan. “Unless we measure, we are only guess- ing; so better measurement – both before, during and after a blast – is the key to optimising blast results,” he said. “Drones

the client,” Swanepoel comments. The X-Series of versatile and powerful IG units from SEW-EURODRIVE is said to provide an ideal solution for conveyor belt drives, with a torque range from 6,8 kNm to 475 kNm. It also features a large number of accessories to allow for maximum flex- ibility, and a wide range of gear ratios for helical and bevel-helical gear units. Nearly any mounting position or shaft arrangement on a driven machine can be implemented. A reversible gear unit hous- ing also facilitates variable installation. The robust housing, low-noise gearing and cooling system boost safety and ease of maintenance. SEW-EURODRIVE, tel (+27 11) 248-7000 advance our measuring ability greatly when combined with BME’s other innova- tive in-house tools like our blast planning software together with our electronic det- onator system.” The versatility of a drone as a vehicle for the camera also extends to valuable moni- toring functions during and after the blast. What experts can take from the images and graphics is a clearer understanding of what block faces look like, and whether there is any damage or potential problems resulting from the drilling. “Sampling, measuring and quantify- ing the fragmentation achieved by a blast is much easier when done from an aerial scale image that a drone can deliver, mak- ing the analysis much more useful in improving future blasts,” he said. “The dis- tribution and volumes of fragment sizes are important to monitor, as these are vital to continuous improvement strategies.” After a blast, drone images from above give a much clearer picture of where coarser and finer fragments are lying – and in what relative quantities. “It may even be possible to use the images as a basis for actually measuring fragment size in a more scientific way,” he said. “We currently take post-blast photo- graphs but it is difficult to interpret these in a way that is statistically valid.” Software now also allows the creation of a three-dimensional surface of the blast block by combining the aerial drone imagery and the face profile footage from land-based cameras. BME, tel (+27 11) 709-8765

An aerial view from a camera mounted to a small drone clearly showing the hole positions in the drill pattern.

Three more power packs supplied to diamond mine SEW-EURODRIVE is continuing its involve- ment at a major diamond mine in Lesotho by supplying three complete power packs for use on the tailings side of the operation. This follows the earlier successful supply of 20 power packs for the same project.

The initial order was received in December 2014, with technical clarifica- tion in 2015 and delivery in February 2016. The latest order, for the three additional power packs, was received in May 2016, and fulfilled in September 2016. Despite the differing lead times, SEW-EURODRIVE’s local stockholding and value-added ser- vice offering meant that the requirements

50  MODERN MINING  March 2017