Produced petroleum fluids containing hydrogen sulfide (H2S) gas are often referred to as "sour". Hydrogen sulfide gas in the presence of free water can cause certain metal alloys to crack which is referred to as Sulfide Stress Cracking (SSC). SSC of metals is a serious safety issue for the petroleum industry and is addressed by the NACE (National Association of Corrosion Engineers) MR-01-75 document1  which establishes requirements for metallic materials suitable for sour environments. Sour service materials selection is a complex problem often facing personnel not experts in this area.

Since SSC and the NACE MR-01-75 document are not easily understood by most petroleum engineers, an expert advisor computer program was developed to integrate expert comments, SSC fundamentals, key metallurgy concepts, and NACE MR-01-75 requirements.2  This program is termed an expert advisor rather man an expert system because it seeks to teach the knowledge rather than simply provide expert answers. A novice user is able to proceed through a structured tutorial to establish the necessary fundamentals on metallurgy, SSC technology, and NACE MR-01-75 requirements necessary for informed use of the NACE document. More experienced users can proceed directly to the expert system portions of the system for direct evaluation of an alloy specification. A general survey option is available within the expert system portion to evaluate NACE requirements in a general context without being limited to the specifics of a given alloy specification.

This software demonstrates that expert systems technology can be applied to SSC and NACE MR-01-75 to provide expert communication to users.

You can access this article if you purchase or spend a download.