Understanding IS 15490 - The Indian Standard for Sulphide Stress Cracking Resistance Testing
In industries dealing with aggressive service environments—especially those involving sour gas (H₂S)—ensuring the mechanical integrity of materials is not just good engineering practice, it’s critical for safety, compliance, and longevity. One such key quality control measure is Sulphide Stress Cracking Resistance (SSCR) testing, and in India, it is governed by the IS 15490 standard.
This blog explains what IS 15490 entails, why it matters, and how manufacturers and project owners can ensure compliance and safety through this test.
What Is Sulphide Stress Cracking (SSC)?
Sulphide Stress Cracking (SSC) is a form of hydrogen embrittlement that occurs when high-strength steels are exposed to wet hydrogen sulfide (H₂S) environments, typically found in oil & gas extraction, refineries, petrochemical plants, and sour wells. The presence of tensile stress (applied or residual) in such conditions can cause sudden and brittle cracking—often without warning.
What Is IS 15490?
IS 15490:2004 is the Indian Standard titled “Method of test for sulfide stress cracking resistance of metallic materials”. It is based on the internationally recognized NACE TM0177 test method and outlines the procedure to evaluate the SSC resistance of ferrous alloys, particularly steels, under simulated sour service conditions.
This standard ensures that materials used in sour service environments are fit for purpose, reducing the risk of catastrophic failure due to SSC.
Key Features of IS 15490
- Scope
Applicable to metallic materials—especially high-strength steels—used in sour gas environments like pressure vessels, pipelines, valves, fittings, and downhole equipment. - Test Types
Includes multiple test methods such as: - Tensile Test (Method A)
- Bent Beam Test (Method B)
- C-Ring Test (Method C)
- Test Environment
Simulated using aqueous H₂S-saturated solutions, often using NaCl and acetic acid, to create realistic sour gas conditions. - Test Duration
Typically 720 hours (30 days) or as specified by client/project requirement. - Evaluation Criteria
- Visual inspection for cracks
- Microscopic examination
- Pass/Fail criteria based on presence or absence of cracks and embrittlement
- Material Heat Treatment
Materials are often tested in heat-treated conditions to replicate field conditions or design requirements.
Why IS 15490 Matters
- Regulatory Compliance: Mandatory for components used in oil & gas operations under BIS or ONGC specifications.
- Material Qualification: Helps manufacturers qualify their products for sour service usage.
- Failure Prevention: Identifies susceptibility before deployment, helping avoid in-field cracking and costly shutdowns.
- Global Acceptance: IS 15490 aligns Indian testing with global standards.
Industries That Rely on SSCR Testing
- Oil & Gas (Exploration and Refining)
- Petrochemicals
- Pressure Vessel and Boiler Manufacturing
- Pipeline and Valve Manufacturing
- EPC and Offshore Construction
- Drilling and Subsea Equipment
SSCR Testing at Eurofins Spectro
At Eurofins Spectro, we offer IS 15490-compliant SSCR testing backed by:
- NABL accredited and BIS Approved lab
- Experienced metallurgists and corrosion experts
- Customized test setups for client-specific needs
- Failure analysis and consulting support
- Rapid turnaround with accurate, actionable reporting
Final Thoughts
IS 15490 plays a vital role in safeguarding industrial assets from one of the most dangerous forms of corrosion—sulphide stress cracking. Whether you're a manufacturer, EPC contractor, or material buyer, ensuring SSC resistance through proper testing isn't just about ticking a compliance box it's about protecting lives, assets, and brand reputation.