Engineered for high mechanical stress, severe chemical immersion, cryogenic resilience, and zero-defect pressure equipment assemblies across industrial France.
Understanding nitrogen-strengthened austenitic stainless steel for high-integrity structural & pressure equipment connections.
Nitronic 50 utilizes a nitrogen addition (0.20-0.40%) to stabilize austenite while doubling room-temperature yield strength compared to standard grades such as 316/316L or 317L, allowing French design engineers to specify smaller diameter fasteners, dramatically reducing flange assembly mass.
With 20.5-23.5% Chromium, 11.5-13.5% Nickel, 1.5-3.0% Molybdenum, and micro-alloyed Columbium and Vanadium, Nitronic 50 provides a Pitting Resistance Equivalent Number (PREN ≥ 34), vastly outperforming Type 316 in marine splashing, pitting, and crevice attack.
Unlike standard 300-series austenitic stainless steels that become partially ferromagnetic after severe cold heading or cold thread rolling, Nitronic 50 retains exceptionally low magnetic permeability (μ < 1.004) even after severe cold working, essential for sensitive naval sonar and MRI research instrumentation.
| Alloy Grade | UNS / Material No. | Yield Strength (0.2% Offset) | Tensile Strength (Rm) | Pitting Index (PREN) | Magnetic Permeability (μ) | Primary Industrial Sector |
|---|---|---|---|---|---|---|
| Nitronic 50 (Annealed) | UNS S20910 / 1.3964 | ≥ 415 MPa | ≥ 795 MPa | PREN 34-36 | < 1.004 | Naval defense, subsea actuators, chemical pumps |
| Nitronic 50 (High Strength) | UNS S20910 / XM-19 | ≥ 620 - 690 MPa | ≥ 930 - 1000 MPa | PREN 34-36 | < 1.010 | Nuclear reactor instrumentation, high-pressure piping |
| AISI 316L Stainless Steel | UNS S31603 / 1.4404 | ≥ 220 MPa | ≥ 520 MPa | PREN 23-25 | 1.008 – 1.050 (Cold worked) | General industrial, civil construction, mild piping |
| Duplex 2205 | UNS S32205 / 1.4462 | ≥ 450 MPa | ≥ 655 MPa | PREN 35 | Ferromagnetic (μ >> 25) | Desalination plants, oil & gas process risers |
| Inconel 625 | UNS N06625 / 2.4856 | ≥ 415 MPa | ≥ 827 MPa | PREN 45+ | < 1.002 | Extreme aerospace exhaust, subsea sour gas (H2S) |
Directly supporting French EPC contractors, shipbuilders, and nuclear engineering hubs with mission-critical XM-19 fasteners.
France’s major nuclear renaissance, anchored by the construction of next-generation EPR2 reactors across Flamanville, Penly, and Gravelines, demands fastening hardware with uncompromising metallurgical pedigree. TorqBolt’s Nitronic 50 stud bolts and hex nuts provide high yield strength under thermal transients, verified low cobalt content (≤ 0.05% on request for minimal activation), and complete RCC-M and EN 10204 3.1 certification.
Supplying the defense and maritime dockyards of Brest, Cherbourg, Lorient, and Saint-Nazaire (Chantiers de l'Atlantique, Naval Group). Nitronic 50 is specified for through-hull penetrations, non-magnetic pump shafts, marine rudder mountings, and acoustic baffle bolting. Its resistance to severe crevice corrosion in stagnant North Atlantic and Mediterranean seawater ensures zero-maintenance duty cycles.
French offshore wind development off Saint-Brieuc, Fécamp, and the Mediterranean Gulf of Lion subjects structural and electrical mooring fasteners to severe fatigue and aggressive splash-zone chlorides. Nitronic 50 fasteners offer higher endurance limits than standard duplex steels, coupled with superior resistance to microbially induced corrosion (MIC) and stress cracks in marine renewable infrastructure.
Strategic procurement transitions driven by European decarbonization mandates, supply chain derisking, and stringent traceability directives.
French pressure equipment fabricators operating under the French CODAP code (Code de construction des appareils à pression) and the European Pressure Equipment Directive (PED) require fasteners derived exclusively from audited mills with documented Particular Material Appraisals (PMA). Our production flow guarantees full compliance with Annex I chemical and mechanical safety factors.
Engineers across French aerospace corridors in Toulouse and marine hubs in Saint-Nazaire are shifting from standard A4-70 (316) hardware to Nitronic 50. By leveraging Nitronic 50's 415–690 MPa yield capacity, engineers specify M16 fasteners instead of M24, generating up to 45% weight savings on structural pipe racks and topside modules without loss of structural safety margin.
French government contracts and major utility projects (TotalEnergies, Technip Energies, Framatome) mandate witnessed inspection by accredited bodies such as Bureau Veritas (BV), APAVE, or DNV. TorqBolt maintains longstanding protocol frameworks with Mumbai and Rajkot inspection teams to execute smooth 3.2 staging, chemical cross-checks, and impact testing witnessed on-site.
Download our technical fastener catalog, dimensional charts for DIN / ISO / ASME standards, and full material test certificates. Contact our dedicated specialty alloys engineering desk directly.
Get CatalogCombining world-class forging and machining capabilities with rigorous European quality certifications.
Audited and approved by TÜV Rheinland under European Pressure Equipment Directive 2014/68/EU Annex I Paragraph 4.3, qualifying our fasteners for CE-marked boilers, pressure vessels, and piping manifolds.
Our centralized production plant in Rajkot and corporate facility in Mumbai house advanced hot heading, cold forming, thread rolling, solution annealing furnaces, and high-precision CNC turning centers under one integrated QA system.
Zero batch mixing. Every stud, hex bolt, socket cap screw, and nut is stamped with its material grade and heat code. Mill test certificates (MTR) are retained in our digital archiving system for a minimum of 10 years.
In-house Positive Material Identification (PMI via XRF/OES spectrometers), tensile testing at ambient and elevated temperatures, Charpy V-notch impact down to -196°C, micro-hardness (Vickers/Rockwell), and ASTM A262 intergranular corrosion verification.
Direct answers for procurement officers, piping engineers, and quality assurance inspectors.
Send your specifications, drawings, and required inspection tiers directly to our technical sales team for an immediate response within 24 hours.
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