Mining Methods and Machinery · Mining Machinery · 2 marks · Numerical answer
A DERD shearer cuts a2.4 m seam at0.6 km/h with web depth0.5 m. Coal occupies0.24 m² of AFC cross-section. With10% spillage, find minimum AFC speed in m/s to two decimals.
Shearer speed is600/3600=1/6 m/s. Cut volume rate is2.4×0.5×1/6=0.20 m³/s. After10% spillage,0.18 m³/s must be conveyed. Divide by occupied area0.24 m²: v=0.18/0.24=0.75 m/s. This uses spillage as the stated reduction in material arriving at the conveyor.