機器
activity
belts
big
coal
construction
conveyor
digging
dirt
dirty
dust
earth
energy
environment
equipment
extraction
extreme
factory
fuel
geology
global
gravel
grunge
heavy
huge
industrial
industry
machinery
metallic
mine
mineral
mining
moving
ore
pit
power
pulleys
quarry
quarrying
rock
silo
steel
stone
storage
tank
technology
tool
transport
transportation
wheel
work