機器
anthracite coal
blades
brown coal
coal
coal man
coal mine
coal mine excavator
collier
colliery
combustion
current
digger
digging
dredge
dungeon
energy
engineering
excavator
exploitation
factory
fuel and power generation
geology
horizontal
industry
machinery
mine workings
miner
mineral
mining
mining equipment
mining industry
mining machinery
open
ore
pit
power
raw material
rock
rotating
science
sinker
source
surface
underground
wheel