chrome
chromium
connector
construction
control
design
engineering
equipment
faucet
fitting
flange
fuel
gas
gasoline
gauge
icon
illustration
industrial
industry
isolated
isometric
line
mechanics
metal
metallic
meter
oil
petrol
petroleum
pipe
pipeline
piping
plate
plumbing
pressure
pump
red
refinery
sewage
sewer
steel
symbol
tap
technology
treatment
tube
valve
water