Formerly known as , SP0170-2021 is the industry standard for “Protection of Steel in Concrete from Corrosion Using Thermal-Sprayed Zinc Anodes” . It provides guidelines for designing, applying, and maintaining zinc-based thermal spray coatings (metallizing) as a galvanic cathodic protection (CP) system for reinforced concrete structures.
) scales rather than sulfide scales. Consequently, their external surfaces present a significantly lower risk of PTA SCC. Core Mitigation Methods Mandated by NACE SP0170
Prevention starts at the design stage. The standard guides engineers to select materials that are resistant to sensitization. This involves controlling chemistry (low carbon grades like 304L or 316L) or using stabilized grades (like Type 321 or 347) which contain niobium or titanium to prevent chromium carbide precipitation during welding or high-temperature service.
). If these acids interact with sensitized austenitic stainless steels (such as 304 or 316) under tensile stress, rapid intergranular cracking occurs, often causing catastrophic equipment failure upon restart. Key Mitigation Strategies in NACE SP0170 nace sp0170 pdf 2021
The standard (last officially updated in 2018 but widely applied through 2021) tells a "deep story" not of people, but of the silent, invisible war against Polythionic Acid Stress Corrosion Cracking (PTASCC) .
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is the definitive global standard practice for protecting austenitic stainless steels and other susceptible alloys from Polythionic Acid Stress Corrosion Cracking (PTA-SCC) during refinery shutdowns. While often searched alongside the year 2021 due to the merger that formed AMPP (Association for Materials Protection and Performance) , the active technical version remains NACE SP0170-2018 . Formerly known as , SP0170-2021 is the industry
On January 1, 2021, to form the Association for Materials Protection and Performance (AMPP) . Consequently, you may see this document referenced as AMPP SP0170 in the future. However, the technical content of the most current standard (SP0170-2018) has not been superceded by any 2021 version.
The industry baseline is a 1% to 2% sodium carbonate ( Na2CO3cap N a sub 2 cap C cap O sub 3
: Neutralizing acidic components using solutions like soda ash (sodium carbonate). This involves controlling chemistry (low carbon grades like
These acids, combined with residual tensile stress in the austenitic stainless steel (like 300-series stainless), cause rapid crack propagation. Key Mitigation Methods in NACE SP0170-2021
This is the most common protective measure applied to equipment susceptible to PTA SCC.