Present situation of fully mechanized mining technology for steeply inclined coal seams in China

Abundant and widely distributed in China, steeply inclined coal seams generally have diverse and complicated geological characteristics. Intrinsic problems in mining such seams, such as large dip angle, short length of mining face, ineffective sealing and protection of working space by support systems, poor stability of equipment, high labor intensity, and inadequate protection of the workers hinder the safe and efficient excavation. Recently, significant progress has been made in China in mining such coal seams. In some coal mines, fully mechanized mining technology has been successfully applied, and working face outputs were increased remarkably. This paper analyzes the main technical difficulties in applying fully mechanized mining technology, such as surrounding rock control, mining equipment stability control, skidding prevention, and flying gangue prevention. Based on the analysis, prosperous development directions for steeply inclined coal seam mining in China are proposed.