英文關鍵字
assembly
background
bolt
closeup
connect
connection
construction
engineering
equipment
flange
fuel
gas
gasket
gasoline
hardware
heavy
horizontal
industrial
industry
iron
joining
joint
large
manufacturing
metal
metallic
nobody
nut
object
oil
old
part
pipe
pipeline
piping
pressure
pump
repair
screw
seal
stainless
steel
structure
supply
technology
thread
tube
valve
welding