Power PlugA combination of the Power Plug, Air and Mass strategically placed within a borehole to improve blast results and dramatically decrease blasting costs is called the Power Deck System.
Power Decks have and are being used by various operations to eliminate 10-50% of explosive product, reduce vibrations up to 75%, and reduce airblast/flyrock by to 100%. In view of the reduced explosive consumption, the fragmentation distribution remains unchanged or is actually increased in some operations, while reducing the undesirable fines content in others.
It is proven that by focusing most of the blast energy in a downward direction: single and multiple Power Deck designs can greatly increase control; stemming length can be dramatically reduced without increasing the danger of flyrock. Sub-drill can be reduced by as much as 100%, and in casting applications the throw volume can be increased considerably.
By varying mass, placement, number, and air gap length, Power Deck hole designs can be tailored to help achieve one or more goals in any blasting operation.
What happens at the bottom of the hole with the Power Deck system can be explained in the terms of the pressure and/or Kinetic Energy: When an explosive detonates in a borehole, the high temperature by-products of the detonation will always take the path of least resistance. The bottom hole air deck will first be subjected to an intense shock wave traveling through it. When the initial shock wave front hits the bottom of the hole, the shock wave speed decreases, reflects from the hole bottom and increases the pressure at that point. At this instant of time, a separate secondary impact from the explosion products adds another impulse to the bottom of the hole. The combined effect is that the resulting pressure P2 at the hole bottom can be increased from 2-7 times relative the initial pressure, P1. The increased point source pressure is sufficient to create a planar split and fragmentation at the hole bottom.
In essence, the sum of the primary shock wave energy and secondary explosion products are much more efficient than a concentrated continuous cylindrical charge at the hole bottom, but only when the bottom hole air deck length and Power Deck’ plug mass are properly designed for the given field conditions and explosives system.
Our experts in this technique will help design your blast to meet your goals.