英文關鍵字
abstract
belt
blue
business
circle
closeup
conveyor
cutting
cycle
design
detail
details
engine
engineering
equipment
factory
future
gear
heavy
industrial
industry
iron
machine
machinery
manufacture
manufacturing
mechanic
mechanical
mechanism
metal
metallic
modern
motor
part
plant
plastic
power
process
processing
production
round
steel
technical
techno
technology
tool
transportation
wheel
work