20 APRIL 2023 WorldWide Drilling Resource® Raising the Limits of Safety with High-Current Detonator Testing Adapted from Information by BME Based in Johannesburg, South Africa, blasting and explosive solutions provider, BME is stretching the boundaries of safety with its initiation system, testing the resistance of its AXXIS Titanium electronic delay detonators (EDDs) to high-current alternating current (AC) voltages. “There are a number of different voltages that underground mines employ for their various machinery and equipment,” said Tinus Brits, BME’s global product manager - AXXIS. “The tests we carried out with an independent research partner were able to show that the AXXIS Titanium EDD is very resistant to highcurrent AC voltages.” The Republic of South Africa Department of Mineral Resources ARP1717 certification is relevant to this aspect of blasting providing a foundation for safety levels expected from blasting equipment, said Bennie van Nieuwenhuizen, quality manager for AXXIS. “In line with our innovation focus and our commitment to safety, the tests we conducted were to push the boundaries even further in the interests of safe blasting and mining,” added Nieuwenhuizen. “We were therefore interested in characterizing the response of our detonators at far higher currents and voltages than the standards require.” These tests are relevant because EDDs are typically deployed in mining environments where the range of energy levels is difficult to predict - as every mine will have their own preferred power supplies. In some mining applications, EDDs are used near electrical wires or electric initiation systems. “This gives rise to the risk that the EDDs could be exposed to high voltages and currents due to human error or equipment failure,” said Andries Posthumus, AXXIS product development manager. “It is therefore important that EDDs should have resistance to initiation when unintentionally exposed to high voltage and current.” He highlighted AXXIS Titanium EDD consists of an encapsulated electronic module, with an electronic-printed circuit board overmolded with plastic material in an exclusive shape. The area closest to the explosive part of the detonator forms a friction fit, as the detonator tube is tapered to the bottom. This creates a seal mechanism, isolating electronic components from the pyrotechnic head and base charge. Testing protocol required specialized high-power inputs, so BME partnered with the National Electrical Test Facility (NETFA). “The tests involved a high-current AC voltage source consisting of a live node connected through a resistor to . . . one wire of the detonator, and the neutral node to the other wire of the detonator,” said BME electronic engineer Van Niekerk. “A remote contactor was used to start the AC exposure while we measured the voltage with a high-voltage probe and measured the current level with a current probe.” Limits were pushed to extreme levels not expected in normal operating conditions, and in all the samples tested, no initiation occurred. “We were pleased with the results of the tests, which showed that BME continues to operate at the highest levels of safety,” said Brits. “Our innovative approach ensures that our ongoing research and testing finds new opportunities for safe and efficient blasting.” A member of the BME Team works with AXXIS Titanium EDDs. EXB
RkJQdWJsaXNoZXIy NDk4Mzk=