Assessment of the effective working time on the mining output of the mechanized longwall (coal seam 11) in Ha Lam coal mine

Abstract

The mechanizetion of Ha Lam coal seam 11 was designed with mining output of 600.000 tous per year. In fact, due to the negative impact of geological conditions as well as the irrationality of the initial production organization, the mining output of the longwall is not reached according to the designed capacity. The paper proposes a method to determine the effective working time of the actual longwall based on each component stage. For specific conditions at coal seam 11 in Ha Lam coal mine. The mean flow rate of the mining stream is considered as a directional factor of the linear function describing the relation between the daily output and the effective mining in the longwall face. This relation is also considered as motivation in particular for supervisory personnel, as it shows advantages resulting from elongation of this time, as well as it shows possible losses of the daily output in a case when the effective working time is given longwall face was shortened.