API RP 578 recommends the chemical inspection of new and existing alloy piping systems using instruments designed for Positive Material Identification (PMI). Inspectors can employ handheld XRF or mobile OES instruments to verify correct alloy grade. The difference in instruments relates to the spectrum of elements able to be analyzed. Mobile OES instruments analyze a greater array of elements then handheld XRF including Carbon, Sulfur, Phosphorous and Nitrogen in duplex steels. Carbon, Phosphorous and Sulfur are the main elements that differentiate alloy grades of steels used in API RP 578. On top of API RP 578, mobile OES is utilized for meeting API 5L guidelines when determining Carbon Equivalent (CE) calculations in the field.
What material needs to be analyzed? Various shapes and sizes such as pipes, elbows, flanges, fittings and weld puddle material, along with other connectors, require analysis. Even new systems under-construction should incorporate PMI for quality assurance from start up. Analysis results are stored on board the instrument or can be downloaded in an Excel format.
If you are planning to conduct PMI analysis in the field contact Verichek Technical Services, Inc. and learn how our mobile instruments help companies meet API standards every day.