Specifications
Surface Treatments
Certifications
- ISO 9001 - 2015 Certified
- PED 2014/68/EC
- NACE MR0175/ISO 15156-2
- NORSOK M-650
- DFAR
- MERKBLATT AD 2000 W2/W7/W10
Hiduron 191 Data Sheet
Hiduron 191 is the high-strength manganese-modified Cu-Ni-Al precipitation-hardened cupronickel The legacy aerospace designation is EB4223A. Hiduron 191 is the NACE MR0175 sour-service qualified grade in the Hiduron family and the procurement default for splash-zone offshore platform riser bolting, naval surface and submarine bolting, and high-strength subsea bolting where the Hiduron 130 yield headroom is insufficient. This datasheet consolidates chemistry, mechanicals, heat treatment, physical properties, certification and applications for procurement and design reference.
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Hiduron 191 Designations
| System | Designation |
|---|---|
| UNS | C72420 |
| Chemical-symbol designation | CuNi14Mn4AlFe |
| UK Naval Engineering Standard | NES 835 |
| UK Ministry of Defence | DEF STAN 02-835 |
| US Department of Defense | DOD-C-24676 |
| Legacy aerospace | EB4223A |
| Sour-service qualification | NACE MR0175 / ISO 15156, at <=286 HBW |
| Originator | Langley Alloys (UK) |
Hiduron 191 Chemistry (Percent by Weight)
| Element | Symbol | Range, percent |
|---|---|---|
| Copper | Cu | balance (~76 to 78) |
| Nickel | Ni | 14.0 to 15.5 |
| Manganese | Mn | 4.0 to 5.0 |
| Aluminium | Al | 1.5 to 2.5 |
| Iron | Fe | 0.5 to 1.5 |
| Silicon | Si | up to 0.10 |
| Lead | Pb | up to 0.02 |
| Carbon | C | up to 0.05 |
Hiduron 191 Mechanical Properties (Solution Annealed and Aged)
| Property | Value | Test condition |
|---|---|---|
| Tensile strength (Rm) | 820 to 1000 MPa | RT, longitudinal |
| 0.2 percent proof stress (Rp0.2) | >=580 MPa | RT, longitudinal |
| Elongation A5 | >=15 percent | RT, longitudinal |
| Reduction of area | >=30 percent | RT, longitudinal |
| Hardness (HV) | 270 to 320 | RT, Vickers |
| Hardness for NACE service (HBW) | <=286 HBW (28 HRC) | NACE MR0175 limit |
| Charpy V impact | >=40 J | RT, longitudinal |
| Modulus of elasticity | 130 GPa | RT, tensile |
| Fatigue endurance (10^7 cycles, polished) | ~260 MPa | Rotating beam, air |
Hiduron 191 Heat Treatment Cycle
| Step | Temperature | Hold | Cool |
|---|---|---|---|
| Solution anneal | 850 to 900 deg C | 1 h to each 25 mm | Water quench |
| Age | 450 to 480 deg C | 3 to 5 h | Air cool |
Hiduron 191 Physical Properties
| Property | Value |
|---|---|
| Density at 20 deg C | 8.65 g/cm3 |
| Modulus of elasticity | 130 GPa |
| Thermal expansion (RT to 300 deg C) | 16.5 x 10^-6 / K |
| Thermal conductivity at 20 deg C | 26 W/m.K |
| Specific heat capacity | 415 J/kg.K |
| Electrical resistivity at 20 deg C | 0.45 microhm.m |
| Magnetic permeability (mu_r) | <1.005 (non-magnetic) |
Hiduron 191 Primary Applications
- Splash-zone offshore platform riser bolting: over 15 years of in-service performance on North Sea and Gulf of Mexico platforms.
- Naval surface and submarine bolting: NES 835, DEF STAN 02-835 and DOD-C-24676 procurement on UK Royal Navy, US Navy and allied programmes.
- Mine-countermeasure (MCM) vessels: mu_r below 1.005 magnetic-permeability qualification.
- Sour-service oil and gas bolting: NACE MR0175 / ISO 15156 qualified at the 286 HBW (28 HRC) hardness limit.
- Subsea hydraulic connectors at high strength: where Hiduron 130 yield headroom is insufficient.
Hiduron 191 Forms and Sizes
| Form | Range | Page |
|---|---|---|
| Round bar | OD 16 to 250 mm | Round Bar |
| Stud bolts | M12 to M100, 50 to 600 mm | Stud Bolts |
| Hex bolts (DIN 931 / ISO 4014) | M12 to M64 | Hex Bolts |
| Heavy hex bolts (ASME B18.2.1) | 1/2 to 3 inch | Heavy Hex Bolts |
| Anchor bolts | M16 to M64 | Anchor Bolts |
| Nuts and heavy hex nuts | M12 to M100 | Nuts |
| Washers | M12 to M48 | Washers |
| Forgings | up to 600 kg piece | Forgings |
EN 10204 Certification and Inspection
Every Hiduron 130 and Hiduron 191 stock and finished fastener ships with EN 10204 type 3.1 mill test certificate as standard. Type 3.2 third-party witness by Lloyd's Register, DNV, BV, SGS or TUV is supplied on call-out and is standard practice on naval and subsea procurement orders. The certificate carries the melt heat number, full chemical analysis to the controlling specification, solution-anneal plus age cycle parameters, tensile and yield results, hardness, Charpy V impact result where called out, and the dimensional report. For Hiduron 191 sour-service orders, an additional NACE MR0175 hardness certificate confirms that every test piece reads below the 286 HBW (28 HRC) limit.
Request a Quote on Hiduron Bolting
TorqBolt supplies Hiduron 130 (UNS C72400, DTD 900/4805) and Hiduron 191 (UNS C72420, NES 835, DEF STAN 02-835, DOD-C-24676) in round bar, stud bolts, hex bolts, heavy hex bolts, nuts, washers, forgings and machined components. Standard fastener lead time is 4 to 8 weeks from order, subsea machined components quote project-specific lead time. Send an enquiry through TorqBolt Contact with the controlling specification, the form factor, the size envelope and the certification level (3.1 default, 3.2 on call-out, NACE on call-out).
Request a Quote on Hiduron 130 and Hiduron 191 Bolting Stock and Fasteners
Hiduron Controlling Standards
| Standard | Scope | Relevance |
|---|---|---|
| NES 835 | UK Naval Engineering Standard for Cu-Ni-Al bolting | Hiduron 191 controlling spec |
| DEF STAN 02-835 | UK Ministry of Defence adoption of NES 835 | Hiduron 191 MoD procurement |
| DOD-C-24676 | US Department of Defense Cu-Ni-Al spec | Hiduron 191 US Navy procurement |
| DTD 900/4805 | UK Air Ministry specification | Hiduron 130 original spec |
| NACE MR0175 | Sour service materials qualification | Hiduron 191 qualified to 286 HBW limit |
Related Hiduron Property Pages
- Chemical Composition: Element ranges for both grades with role notes for each addition.
- Mechanical Properties: Yield, tensile, elongation and hardness at room and elevated temperature.
- Heat Treatment: Solution-anneal plus age cycle for gamma-prime Ni3Al precipitation.
- Seawater Corrosion: Cu-Ni-Al passive film behaviour in flowing seawater.
- SCC Resistance: Stress-corrosion cracking and hydrogen embrittlement immunity.
- Magnetic Permeability: Non-magnetic naval and aerospace qualification.
- Machinability: Cu-Ni-Al cutting parameters and tooling notes.
- Density and Physical Properties: Density, modulus, thermal expansion, conductivity.
Reference and Downloads
- Hiduron 130 Datasheet: Consolidated chemistry, mechanicals and heat treatment.
- Hiduron 191 Datasheet: NACE-qualified naval and subsea grade datasheet.
- Bolt Dimensions: Imperial and metric thread, head and stress-area tables.
- Torque Chart: Cu-Ni-Al fastener torque values, dry and lubricated.
- FAQ: Consolidated questions on Hiduron specification, certification and supply.
Hiduron 191 Datasheet FAQ
Q. Where can I download the Hiduron 191 PDF datasheet?
The PDF datasheet is available on request through TorqBolt sales. The HTML version on this page consolidates the same chemistry, mechanicals, heat treatment, physical properties, certification and applications content.
Q. What is the Hiduron 191 controlling specification?
NES 835 (UK Naval Engineering Standard) is the primary controlling spec, adopted by DEF STAN 02-835 (UK MoD) and cross-referenced by DOD-C-24676 (US DoD). The alloy is registered as UNS C72420.
Q. Is Hiduron 191 NACE MR0175 compliant?
Yes. Hiduron 191 is qualified to NACE MR0175 / ISO 15156 for sour-service bolting at or below 286 HBW (28 HRC). The certificate reports the hardness reading as the NACE evidence.
Q. What is the standard lead time on Hiduron 191 bolting?
4 to 8 weeks from order on standard fastener sizes. Naval and sour-service certification orders quote project-specific lead time to accommodate the third-party witness inspection schedule.
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