Mining Methods and Machinery · Mining Methods · 2 marks · Numerical answer
A unidirectional DERD shearer works a1200×200×2.4 m panel. Drum diameter1.4 m,web0.6 m,cutting speed5 m/min,return speed10 m/min,and delay between cuts2 h. Two8-h shifts are available daily. Find whole days for complete extraction.
One cut traverses the200 m face in40 min and the return takes20 min. Add120 min operational delay for a180 min cycle. Retreat requires1200/0.6=2000 cuts. Total time is6000 h;at16 h/day this is375 days. The panel width,not its retreat length,is the traverse distance;drum diameter does not replace seam thickness in this cycle calculation.
More Mining Methods questions
GATE 2024 MN Q42– Match geometry P tabular/moderately steep, Q tabular/flat, R massive/steep; strength L…
GATE 2024 MN Q59– The shaded longitudinal section shows recovered ore in a repeating stope layout. Thickness…
GATE 2024 MN Q64– A continuous miner cuts a 5×3 m face with 0.6 m web, one full-height web each 9 min. Two…
GATE 2023 MN Q20– A competent copper orebody is tabular, nearly flat (dip below 30°), less than 2 m thick…
GATE 2023 MN Q34– A 3.0 m coal seam is mined by a double-ended ranging drum shearer with 0.5 m web depth.…
GATE 2023 MN Q45– A surface miner has drum width 3 m, cutting depth 20 cm, cutting speed 25 m/min and pit…