Fracture of Solid Inclusions by Picks
Yu. N. Linnik, V. Yu. Linnik
State University of Management, Moscow, Russia
Keywords: Coal-cement block, solid inclusions, peak cutting force, cut width and depth, mineral type of solid inclusion, orientation of pick relative to inclusion, inclusion-rock cohesion, solid inclusion tear-out
Abstract
According to classification of coal seams with solid inclusions, all mine seams are divided into three groups subject to the size and content of the inclusions in a seam. It is found that fracture efficiency and maximal loads depend on the mineral type of inclusions. Carbonate and pyrite inclusions are fractured in a few cuts, while carbonate-pyrite inclusions are usually broken in a single cut. The loading of a pick is approximately 1.6-1.7 times higher in cutting pyrite inclusions as compared with carbonate inclusions. The authors identify five basic types of the pick-solid inclusion interaction: central and edge cut; touch; tear-out; extraction. The highest loads appear in cutting of solid inclusions and should be taken into account in designs of cutting heads and power drives of mining machines.
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