Azerbaijan State Oil and Industry University, Baku, Azerbaijan:

R. T. Ismaiylov, Head of a Chair, Associate Professor, Candidate of Engineering Sciences, rasim49@mail.ru
I. Z. Gasanov, Associate Professor

Blasthole drilling in open pit mines is carried out using different-type drilling rigs. The capacity of roller-bit drilling (50–70 cm per shift) is much higher than other type drilling rigs have (18–35 cm per shift), and roller-bit drilling enjoys more often use in open pit mines therefore. Performance of roller-bit drilling rigs is known to be affected by specific axial load per unit diameter of bit, strength and abrasive ability of rocks, bit design (shape, size, diameter), bit wear in drilling, bottomhole cleaning efficiency, bit speed and design of the drilling rig. The joint effect of the listed factors on the penetration rate and productivity of roller-bit drilling rigs is the subject of various theoretical and applied researches. However, the fundamental solution yet remains to be found. Enhancement and improvement of qualitative and quantitative figures of roller-bit drilling rigs is a challenging problem of the day. This article analyzes the rate of roller-bit drilling and the ways of speeding it up. For the assessment of the integrated effect exerted by the physical and mechanical parameters of rocks, as well as their strength and abrasive ability, axial load on bit, diameter and wear of bit, bottomhole cleaning efficiency, etc., the authors propose a mathematical model capable to estimate drilling rate as a function of these factors. Using the modeling results, the cross plots of the drilling penetration rate, bit load, bit diameter, initial bit bluntness and and rate speed of bit have been obtained.

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