primary sealing in the Oil and Gas Industry (praɪmɛri silɪŋ)
( Extractive engineering : Downstream facilities , Terminals )secondary sealing
To prevent the escape of vapor from this gap in the tank, primary sealing in the form of foam is used.
When floating roof tanks were first devised, they were fitted with just one primary sealing system but recent legislation, which limits vapor emissions, has meant that a secondary seal is now needed.
Primary sealing is devices used for sealing tanks, to reduce emissions, often made of foam.
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