The effectiveness of the use of non-blasting layer-by-layer milling technology is
considered taking into account the main factors that influence it:
speed and thickness of milling of the rock layer;
physical and mechanical properties of rocks;
the width and length of the active work front.
The technology of layer-by-layer development of rock and semi-rock rocks by
surface miners has the disadvantages associated with the use of a set of traditional
technological schemes, which are intended for the development of mines of small
depth. Technological schemes for the development of the rock mass by combines
stratified milling, even partially not improved for the adaptation and rational work of
combines in such specific conditions of development of iron ore deposits.
High-performance mining equipment performs layer-by-layer mining of the ledge
for its entire height with the open mining of mineral deposits, allows for efficient non-
blasting mining of rocks with an uniaxial compression strength of 120รท140 MPa [7].
The disadvantage of the technology of layer-by-layer milling of rocks of the ledge
in the development of rock mass according to the above work [7] is that the layered
mining of the ledge occurs mountain combine without touching the rocks of the prism
of possible collapse. As a result, a pillar is formed on the edge of the ledge represented
by prism rocks of possible collapse. In this case, the milling combine stops its work
until the pillars are worked out by other means, as a result, the milling type harvester
performs a large number of idle movements. And also increases the downtime of
mining and transportation equipment.
The implementation of the technology of layer-by-layer milling of rocks of the
working platform of the ledge is carried out by mountain combines according to two
main technological schemes of their movement:
scheme of movement of combines with a turn at the end of the waste rock strip;
the shuttle pattern with combines returning idling to the starting position of the
next rock band [8,9].
Analysis of the work and materials of research carried out in this direction
suggests that the combine method of mining the rock massif is one of the least energy-
consuming, ecological and economic in appropriate working conditions. And they
require a review of the established patterns of operation of milling combines between
the technological parameters of mining equipment and the parameters of the elements
of the development system. This will show the reality of solving the problem of
creating and improving the technology of developing semi-rock and rock rocks by
introducing high-performance and high-performance excavation-loading equipment
without conducting a set of drilling and blasting operations when mining iron ore
deposits.
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