Iso 21457 Materials Selection And Corrosion Control For Oil And Pdf New! Jun 2026

| Material Class | Typical Applications | Limits per ISO 21457 | |----------------|----------------------|------------------------| | | Pipelines, vessels, wellheads | pCO₂ < 0.5 bar, or with inhibition; T < 150°C for sour service | | Low Alloy Steel | Downhole tubulars (L80, C95) | H₂S limits defined by hardness < 22 HRC | | Corrosion Resistant Alloys (CRA) – Martensitic SS (13Cr) | Sweet wells, low H₂S | pCO₂ up to 10 bar, pH₂S < 0.01 bar | | CRA – Duplex (22Cr, 25Cr) | Sour, high CO₂, chlorides | pCO₂ > 2 bar, Cl- up to 100,000 ppm | | CRA – Nickel Alloys (Inconel 625) | HPHT, severe sour | Unlimited (cost-driven) | | Non-Metallics (GRP, Liners) | Water injection, low pressure | Temperature limited (<120°C) |

ISO 21457 provides detailed methodologies for assessing the corrosivity of the environment. Unlike simpler guidelines that may look only at H₂S partial pressure, ISO 21457 necessitates a holistic view, including: | Material Class | Typical Applications | Limits

. It acts as a bridge between high-level engineering needs and the practical use of documented, available materials. iTeh Standards Core Purpose and Scope Target Systems : Applies to everything from the iTeh Standards Core Purpose and Scope Target Systems

Materials selection is only half the battle. The standard outlines when and how to implement control measures, including: wellheads | pCO₂ &lt