機器
alloy
automotive
ball
body
bolts
buttwelded
carbon
cast
clean
closeup
concept
conduit
connection
conservation
construction
design
dump
engine
engineering
environment
facility
flange
forging
gas
handle
industry
joint
machined
manufacture
manufacturing
mashine
mechanical
metal
metallic
nuts
oil
part
pipeline
screw
screwed
shiny
shutoff
stack
stainless
steel
technician
tool
valve