inspection hatch for a technological column for installation at a refinery, for the production of gasoline

branch chemical cleaning coke column construction cosmonafta crane cutting cylinder device economy elimination equipment fencing fire furnaces gas gasflame gasoline green hatch heating high hydrant inspection installation insulation ladder manufacture metal metalwork module oil operator overhaul oxygen pipe pipeline plant preparation production propane refinery refining replacement safety ship space specialist straps technological temperature truths union vertia welder welding workers