THE MODERATE LONGHOLE BLASTING FRAGMENTATION CONTROL TECHNOLOGY RESEARCH IN UNDERGROUND MINE

The scallop moderate longhole blasting mining method in Da Hong-shan copper mine applications accounted for more than 61% of the total amount of mining, but the large output rate restricts the mines for ore strength, The average lump ore as high as 22.7%. In order to realize the mine production efficient development, the circular moderate longhole blasting technology and field test. The test results show that circular hole blasting can reduce the block rate is reduced to 10.3%, and the traditional scallop moderate longhole blasting mining compared with the average lump ore decreased by 12.4 percentage points. The panel on duty for the day ore quantity increase 152.31t, increase rate is 51.1%. Reduces the handling of large time delay and secondary crushing of explosives and the consumption of detonators, the efficiency of drawing and at the same time, reduce the mining cost , achieved good blasting effect.