IMPACT OF DRILLING ANGLE ON BLASTING COSTS IN SURFACE WORKS

The removal of rock masses or their use with surface exploitation requires that this work be done at the lowest possible cost. The reduction of operating costs is done by analyzing each work action, working method, and the possibility of changing them, to have an impact on reducing costs. The drilling angle is one of the most important factors during surface exploitation by blasting. By changing the drilling angle, we achieve a reduction of the total drilling length, to have a reduction of the amount of explosives and other changes during the blasting process which do not greatly affect the cost of blasting. Determining the impact of drilling angle on the cost of blasting is determined by analytical methods and by comparing the results of applied drilling angle methods. During the analytical analysis of the blasting data and the comparison of their results, which was performed to determine the change in the cost of blasting depending on the drilling angle, and it concluded that for the removal of 200000 (m3) rock material, 356167.98 (€) can be saved, by applying the 90° angle drilling method. This change of drilling angle from the projected angle of 63° to the angle of drilling 90°, reduces the total cost of blastings by about 10.69 (%).