機器
blade
circle
closeup
dam
depth
design
dirty
disk
energy
engine
engineer
engineering
equipment
factory
gear
helical
industrial
industry
involute
iron
joint
manufacturing
measure
mechanical
metal
metallic
part
precision
production
project
quality
ratio
rusty
sawtooth
sharp
sluice
space
steel
strength
technology
teeth
turning
valve
water
water gate
wheel
work