JUSTIFING OF PARAMETERS OF PNEUMOPERCUSSION MACHINE FOR FORMATION MAIN CRACKS FROM HOLE OF NATURAL STONE

In the work, issues of development of percussive machine for directed destruction of stone rocks are considered. The percussive machine impacts to rock destructive tool implemented into the hole, after that rock wedging and growth of main crack along blast-hole line occur. For that purpose, pneumatic machine of percussion action and gravitational type is chosen. Scheme of the machine is justified based on dynamic simulation of its key assembly units, numerical analysis of constructive and energetic parameters is carried out. Working cycle of the device has been estimated by energy value, percussion frequency, compressed air discharge. It is established that working cycle of gravitational pneumo-percussion machine with elastic valve provides economy of compressed air discharge and high energy of the strike. Results of numerical simulation are proved by experimental data of Institute of Mining.