Research on drawing coal effects in the dipping and steep——dipping coal seams

摘要

Controllable drawing roof coal mining method is applied either to rently inclined seam or to big dipping seam. This paper sums up four corresponding methods according to conditions of our country, and analyses the coal-recovering effects and proves applicated conditions and measures for improving by "drawing coal theory of the ellipsoid". Its conclusion basically consists with practice. This work is of guiding meaning for designing drawing coal technology.