機器
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background
bolt
brown
concrete
connection
construction
designation
detail
direction
engineering
equipment
fasteners
fastenings
green
industrial
industry
iron
line
material
metal
metallic
nut
old
outdoor
railroad
rails
railway
reliability
road
safety
screw
sign
sleepers
station
steel
stiffness
stone
support
symbol
technology
texture
traffic
train
transport
transportation
travel