Corrosion under insulation

Corrosion under insulation can pose a threat of asset integrity. A hydrocarbon condensate 8” pipe line elbow under insulation detect loss of wall thickness cause a pin-hole leak. This thickness come down due to low flow or stagnant condition of the pipe line as it is a by-pass of a preheater which was not expected continuous flow. Since small amount of hydrocarbon will vaporize quickly and spread in the atmosphere and will not allow to detect in the fixed gas detector in LEL or H2S although it was leaking several days. When weather change and due to high humidity, hydrocarbon cloud condenses and dripping to ground floor with hydrocarbon smell. Regular checking of pipe line suggested from RBI will expose early detection of wall thickness and can take appropriate actions to reduce such incident.