Modern Quarrying Q1 2020

BLASTING

Independent studies show that the Varistem can increase blast pattern spread by 10% or more, with the same fragmentation for major savings in drilling and explosive costs.

OPTIMISING BLAST OUTCOMES

O f the various products that have come to market to improve blast performance, flyrock control and productivity, stemming plugs have probably been looked upon with some incredulity. At a time when quarries are contending with shrinking business due to a stressed construction sector, ERG Industrial, a young company that in 2019 acquired the distribution rights of the Varistem stemming plug range from United States company, MOCAP, believes stemming plugs are an opportunity to increase efficiency for quarries and mines, thus reducing costs. Eugene Preis, MD of ERG Industrial, explains that stemming plugs are placed between the explosive column charge and stemming. Plugs work by creating an additional blocking effect within the drill hole when blast energy is released, directing more energy into the block and less energy upwards out of the drill hole. Upon detonation of the explosives, the plug is forced upward into the stemming material and “locks up”. The explosives gases and energy are prevented from travelling (venting) up Having secured distribution rights for the Varistem – a patented blast stemming plug for mining, quarrying and civil blasting applications – South African-based ERG Industrial is currently doing local trials to prove the potential productivity increase and downstream savings stemming plugs can provide to local quarries and mines, writes Munesu Shoko .

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MODERN QUARRYING QUARTER 1 - 2020