and other sensitive alloys from PTA SCC. This type of cracking typically occurs during refinery downtime (shutdowns or turnarounds) when sulfide corrosion products on equipment surfaces react with oxygen and moisture. ANSI Webstore Why the 2021 Update Matters While the core technical guidance remains rooted in the 2018 revision , the industry saw a major shift in 2021 when NACE International merged with (the Association for Materials Protection and Performance). Standard updates in this era focus on: Environmental Realism
The NACE SP0170 PDF 2021 standard provides critical guidelines for corrosion prevention in carbon steel pipelines. By understanding and implementing the recommendations outlined in this standard, pipeline operators can ensure the integrity and longevity of their pipelines, while minimizing costs and environmental risks. As the pipeline industry continues to evolve, the importance of effective corrosion prevention and control will only grow, making NACE SP0170 PDF 2021 an essential resource for pipeline operators and corrosion professionals alike. nace sp0170 pdf 2021
: Keeping the system under a dry nitrogen purge to prevent the reaction that forms polythionic acid. Neutralization and other sensitive alloys from PTA SCC
AMPP - The Association for Materials Protection and Performance Core Objectives of SP0170 Standard updates in this era focus on: Environmental
: Maintaining a dry air environment to prevent the liquid water formation necessary for PTA to develop. ANSI Webstore Standard Structure General scope and application Selection of materials and fabrication practices Dry nitrogen purging to exclude oxygen Alkaline washing of equipment surfaces Use of dry air to prevent water formation Special considerations for reactors Appendix A Background information on the PTA SCC mechanism Accessing the PDF As NACE is now part of
SP0170-2021 applies to:
Hardness is the single most important indicator of SSC resistance. The 2021 PDF introduces more stringent maximum hardness values for heat-affected zones (HAZ) in welds, especially for components exposed to H₂S partial pressures above 10 psi.