Coal Age

SEP 2018

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20 www.coalage.com September 2018 blasting Technology vs. Sales — The Ongoing Battle in the Blasting Business How to avoid getting caught up in technology hype that does not present any real advantage by anthony konya and dr. calvin j. konya A good technological approach to blast- ing has been distorted for decades to help increase the sale of expensive prod- ucts — often without a need and paid for by the consumer. This article discusses the modern sales techniques and how to avoid getting caught up in hype that doesn't present any real advantage. Every industry faces a time when some people begin putting profit over technical principles in an effort to sell more, faster. After the initial adoption of these practices, the competition in the industry quickly puts similar programs together to keep up — training their em- ployees to believe in these systems, even when they are not technically correct and better alternatives exist. This is hap- pening in the blasting business today. The purpose of this article is to in- form both the reader and the "expert" on where the industry has gone wrong with these systems and the proper methods for using them. This is not a technical guide, but a red-flag warning to those who work with rock blasting. This infor- mation could save a mining operation hundreds of thousands of dollars a year. For the blasting professionals servicing the mines, this information will allow them to retain a loyal customer and be- gin to actually improve processes. It is time for the rock blasting industry to be more transparent and focus on technical data and a scientific approach to prob- lems — not sales. The concepts for this article were de- veloped at the recent International Soci- ety of Explosive Engineers conference as the authors sat through paper after pa- per discussing these sales methods pre- sented as technical information. The au- thors of those papers, after presenting, were quickly shut down with questions from experts, who are actively working in the rock blasting business. The results of these "studies" did not work and were worse than systems that were in place more than 50 years ago. To better understand the situation, let's rewind to the 1970s when the ex- plosive industry was in a heated debate between sales and technical principles. It Started 50 Years Ago It all started with Dr. Hino from Japan — a physicist who had probably never fired a real rock blast in his life — and the invention of high-speed cameras. Dr. Hino took high-speed photographs of unconfined explosives breaking rock columns in the 1950s showing what he believed to be the effect of shock-wave spallation. Only one problem exist- ed with his work, when analyzing the powder factor of his charge, it was ap- proximately eight times that of actual rock-blasting applications. Shock breakage was quickly accepted as the must-be situation because models where already in place to mathematical- ly calculate these shock waves. It was a new era of government funding to uni- versity professors looking to study this phenomena that ensured large grants and tenured tracked positions. After a few years, this spread into the hearts of powder industry companies across the world. There was one problem, however, the theory and effects of shock breakage did not ever show up in the field. The explosive and powder companies spent millions to attempt to show it work- ing, including DuPont who did years of studies, and could never find evidence to prove it. In fact, after decades of full- scale research, they discovered that it had to be something else contributing to the breakage of rock. In addition to this, experts in rock blasting at the time, such as Dr. Cook (inventor of water gels) and Ulf Lang- fors, were consistently saying that shock breakage theories had no practical ap- plicability in the rock blasting industry. Research performed in Sweden by Per Anders Pearson stated that for shock breakage, spalling, to occur to a mini- mal degree, approximately 8.5 pounds of explosive per cubic yard was needed — which was not done in commercial blasting. Sure, they work for military applications where very large explosives loads are used in surface charge appli- cations, but they did not contribute to any practical breakage in rock blasting. Why did these theories then stick around for decades in rock blasting? One simple reason — they dramatically increased the sales of expensive explosives when the industry was fighting against the sale of ANFO, and in some parts of the world, these old sales tools are regaining new light. How did this increase sales of expen- sive explosives? With the advent of the shock-wave theory, the basic principal of impedance matching began to take flight. What this principal said was that, if a shock wave is moving through an object and comes into contact with a different object, only a portion of the strength of the shock wave is transmitted and the remaining portion is reflected. Imagine a shock wave moving from steel into copper, only a percentage of that shock wave would go into the copper and the rest would travel in the opposite direction through the steel. The closer the speed of sound through those materials was to the density of those materials, the more energy from the shock wave was transferred. This became known as the acoustical impedance mismatch theory and the goal was then to have the imped- ance (density times the sonic velocity) of the rock match the impedance (densi- ty times the detonation velocity) of the explosive to maximize the energy of the shock wave going into the rock. How-

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