This recommended practice (RP) is applicable to hydrocarbon process streams containing sulfur compounds@ with and without the presence of hydrogen@ which operate at temperatures above approximately 450 ??(230 ?? up to about 1000 ??(540 ??. A threshold limit for sulfur content is not provided because within the past decade significant corrosion has occurred in the reboiler/fractionator sections of some hydroprocessing units at sulfur or H2S levels as low as 1 ppm. Nickel base alloy corrosion is excluded from the scope of this document. While sulfidation can be a problem in some sulfur recovery units@ sulfur plant combustion sections and external corrosion of heater tubes due to firing sulfur containing fuels in heaters are specifically excluded from the scope of this document.
API RP 939-C-2009 history
2019API RP 939-C-2019 Guidelines for Avoiding Sulfidation (Sulfidic) Corrosion Failures in Oil Refineries (SECOND EDITION)
2009API RP 939-C-2009 Guidelines for Avoiding Sulfidation (Sulfidic) Corrosion Failures in Oil Refineries (FIRST EDITION)