NORSOK Flanges Suppliers

While NORSOK flanges share certain dimensional similarities with international standards like ASME B16.5 or EN 1092-1, they are not always interchangeable due to specific technical and certification differences:

1. Design Basis: NORSOK standards are developed for the Norwegian petroleum industry and focus on offshore safety, material traceability, and corrosion resistance, especially in harsh environments.
2. Tolerances & Testing: They often require stricter dimensional tolerances, higher impact testing, and compliance with NACE MR0175 or ISO 15156.
3. Gasket Compatibility: Gasket faces and pressure ratings may differ, causing misalignment or sealing issues with non-NORSOK systems.
4. Documentation Requirements: NORSOK flanges usually demand EN 10204 3.1/3.2 certification, which may not be mandatory under other standards.

For critical offshore and subsea applications, always verify full compliance — mixing standards without engineering validation is not recommended.

NORSOK flanges are specifically engineered to meet the rigorous demands of the Norwegian oil and gas sector, but their usage has expanded into other high-risk, high-performance industries due to their robust specifications. They are commonly used in:

• Offshore Platforms & Subsea Installations
• FPSOs (Floating Production Storage & Offloading units)
• Petrochemical Plants
• Hydrogen and Ammonia Handling Units
• Refineries operating in Arctic or corrosive environments

Key reasons why NORSOK flanges are preferred:

• Stringent Material Quality: Typically specified in Duplex (UNS S31803), Super Duplex (UNS S32750), Inconel, and other high-alloy grades for extreme corrosion resistance.
• Enhanced Safety & Traceability: Comes with full traceability, third-party inspection reports, and EN 10204 3.2 certification when required.
• Standardized for Harsh Environments: Designed for extreme temperatures, pressures, and aggressive chemicals.
• Global Recognition: Though Norway-specific, many offshore EPC contractors and global energy firms mandate NORSOK-compliant products for reliability and long-term performance.

This wide industry acceptance stems from NORSOK’s commitment to safety, durability, and lifecycle cost efficiency.

NORSOK flanges are specially developed to meet the harsh demands of offshore oil and gas platforms, especially where sour service (H₂S exposure), high salinity, and temperature fluctuations are prevalent. To ensure long-term integrity under such conditions, the standard enforces stringent metallurgical and mechanical requirements:

Key material integrity factors include:

1. NACE MR0175 / ISO 15156 Compliance: Materials are resistant to sulfide stress cracking (SSC), especially in wet H₂S environments.
2. Corrosion-Resistant Alloys (CRA): Grades like Duplex (UNS S31803), Super Duplex (UNS S32750), Inconel 625, and 6Mo are preferred for their excellent pitting and crevice corrosion resistance.
3. Low Carbon & Impact-Tested Materials: Flanges undergo Charpy V-notch testing at sub-zero temperatures (typically -46°C) to ensure toughness and prevent brittle fracture in Arctic and deepwater conditions.
4. Controlled Microstructure & Inclusion Ratings: Ensures no metallurgical anomalies that can lead to stress cracking during service.
5. Strict Heat Treatment & Manufacturing Control: Including solution annealing and forging traceability to meet NORSOK M-650/M-630 procedures.

These features make NORSOK flanges ideal for subsea systems, risers, pipelines, and topside equipment, where failure is not an option.

At Nutech Overseas, we proudly export high-quality NORSOK standard flanges to some of the most demanding offshore and subsea engineering markets across the globe. These include:

Major Export Destinations:

• Norway – For use in Statoil (Equinor) and other North Sea operations.
• United Arab Emirates (UAE) – Supplying to ADNOC and offshore EPC contractors.
• Saudi Arabia – For Aramco-approved projects and pipeline installations.
• Qatar – Used in LNG plants and offshore oil platforms.
• Kuwait & Oman – Trusted by petrochemical and refinery sectors.
• Singapore & Malaysia – For deepwater projects and FPSO units.
• United States (USA) – Meeting NORSOK and API crossover specifications.
• United Kingdom (UK) – For North Sea offshore and onshore installations.

All flanges are shipped with full material traceability, 3.1/3.2 certification, and packaging suited for international transport. We provide customized export documentation, marking as per project specs, and fast delivery timelines — making us a trusted global supplier of NORSOK-compliant flanges.