Today’s commercial explosives have resulted from a gradual evolution that began over 600 years ago. Black powder was first used in guns around the 14th centaury. But it was not until the 17th Centaury that this explosive began to replace fire setting as the principle method for loosening rock. As black powder became accepted in the mining Industry, the number of accidents increased and a need for safe explosives and initiating systems emerged. . IN- HOLE DELAY SYSTEM, CHARGING & POSITIONING PRIMER
Blast holes which are too deep must to back filled to the correct depth to prevent excessive vibration and damage drilled are also caused by excessive blast hole depth on upper benches. Bore hole charging, any blocked blast holes should be cleared with a charging pole or steel bar. It may be necessary to bring a drill back to the blast to clear, or re-drill some blast holes. A torch or mirror is often useful to examine the blast hole for blockages, cavity or rough sections before charging. Blasting in Mines - Video Clips. Blast Hole Open Stopes ,
Controlled blasting in an open-pit mine for improved slope stability.A controlled blasting programme (presplitting) was adopted in an open-pit copper mine in order to improve the stability of the resulting cut slopes. The aim was to reduce over break and minimize damage to the final pit walls from production blasts. The use of presplitting allowed considerably higher benches to be adopted with much steeper overall slope angles.