Nace Sp0170 Pdf 2021 💯 Trusted
Compared to previous versions (2003, 2012), the 2021 revision includes:
NACE SP0170 (2021) strengthens industry guidance for External Corrosion Direct Assessment by emphasizing data quality, multi-method indirect inspection, probabilistic ranking, uncertainty quantification, and feedback from direct examinations. While ECDA is a powerful tool—especially for locations where direct inline tools are impractical—its effectiveness depends heavily on the quality of input data, appropriate selection and combination of indirect techniques, and disciplined verification. Operators should treat SP0170 as part of an integrated integrity-management strategy that includes CP optimization, targeted excavations, and, where feasible, complementary inspection technologies.
If you’d like, I can:
(Optionally, I can also extract and summarize specific sections if you provide the PDF.)
Related search suggestions: functions.RelatedSearchTerms(suggestions:[suggestion:"NACE SP0170 2021 ECDA guidelines",score:0.9,suggestion:"External Corrosion Direct Assessment best practices",score:0.8,suggestion:"NACE SP0170 PDF download",score:0.7])
NACE SP0170-2021 (formerly RP0170) is the current standard for the Protection of Austenitic Stainless Steels and Other Austenitic Alloys from Polythionic Acid Stress Corrosion Cracking During a Shutdown of Refinery Units.
This standard provides technical procedures to prevent Stress Corrosion Cracking (SCC) caused by polythionic acids (PTA) that form when sulfide scales on equipment react with moisture and oxygen during refinery downtime. Key Aspects of the 2021 Revision nace sp0170 pdf 2021
Scope: Covers austenitic stainless steels (300 series) and other austenitic alloys (e.g., Alloy 600, 800, 825) used in refinery services where sulfide scales can form. Protection Methods:
Nitrogen Purging: Using dry nitrogen with a low oxygen content to exclude moisture and air.
Alkaline Wash Solutions: Neutralizing acidic components using solutions like soda ash (sodium carbonate).
Dehumidification: Maintaining low relative humidity to prevent the condensation necessary for acid formation.
Application: It is specifically used during shutdowns, turnarounds, or standby periods for equipment such as hydroprocessing units, reformers, and FCC units. Accessing the Paper
Because NACE standards are now managed under AMPP (Association for Materials Protection and Performance), the 2021 version is a protected, copyrighted document. Compared to previous versions (2003, 2012), the 2021
Official Source: You can purchase or download the PDF through the AMPP Store.
Standard ID: The full designation is AMPP SP0170-2021 (Revised 2021-12-10).
The most current official version of this standard is NACE SP0170-2018
"Protection of Austenitic Stainless Steels and Other Austenitic Alloys from Polythionic Acid Stress Corrosion Cracking During a Shutdown of Refinery Equipment." . While you asked for a 2021 version, NACE (now merged into
) typically keeps standards in effect for several years; the 2018 version remains the active guidance for preventing Polythionic Acid (PTA) Stress Corrosion Cracking (SCC) during refinery shutdowns. ANSI Webstore Core Content & Mitigation Methods
The standard provides procedures to prevent the formation of polythionic acids, which occur when oxygen and water react with sulfide corrosion products on equipment surfaces. GlobalSpec Materials & Fabrication (Optionally, I can also extract and summarize specific
: Guidelines for selecting materials and fabrication practices that resist sensitization, reducing the inherent risk of PTA SCC. Dry Nitrogen Purging
: Used to exclude oxygen and moisture from the equipment during shutdown. Alkaline Washing (Soda Ash Wash)
: Neutralizes any PTA that may form. The standard emphasizes that solutions must be properly applied to all surfaces and warns of potential effects on catalysts.
: 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
, you can find the official document and purchasing options through: AMPP Store (Search for SP0170). Authorized distributors like the ANSI Webstore GlobalSpec chemical requirements for the alkaline wash solutions or the specific purging pressures recommended?
NACE SP0170 (2021) serves as a critical industry standard for protecting austenitic stainless steel equipment from polythionic acid stress corrosion cracking (PTA SCC) during refinery shutdowns. The practice outlines essential mitigation techniques, including nitrogen blanketing and alkaline washing, to prevent failures in sensitized stainless steel. While foundational for safety, modern discussions analyze its application alongside advanced, resistant materials. For further technical details, visit GlobalSpec.
NACE SP0170 focuses on External Corrosion Direct Assessment (ECDA), a process intended to evaluate whether external corrosion exists on a pipeline and to direct follow-up actions (inspection, repair, monitoring). ECDA complements other integrity management practices (in-line inspection, hydrostatic testing, cathodic protection surveys) and is particularly applied where direct tools (smart pigs) are impractical or as a supplemental method.
Primary objectives: