Field Identification of Piping Metallurgy

Usually, the spool piece that failed was covered with insulation and not visible. If an operator or engineer had been alert during the turnaround, the improper piping section could have been replaced. 

as process personnel, are not metallurgists. Still, we should be prepared to discriminate between three types of materials  

The 300 series stainless steels contain nickel (316 and 317 also moly). The 400 series chrome steels are intended mainly to resist sulfur and high temperature. The 300 series steels have a greater range of chemical resistance. A handheld instrument is now available to discriminate between carbon steel, chrome steel, and different types of stainless steels. 

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