Table of Contents
- SMO 254 Nuts Overview
- SMO 254 Nuts Specifications
- What are Stainless Steel SMO 254 Nuts?
- SMO 254 Technical Properties & Composition
- Why Industries Prefer SMO 254 Series Nuts
- Types of SMO 254 Series Nuts
- Key Advantages of 6Mo Alloy Nuts
- Key Applications of UNS S31254 Series Nuts
- SMO 254 Nuts vs SS 316L Nuts
- Quality Testing & Inspection
- Global Export Markets
- Frequently Asked Questions
- Contact Aurum Overseas
SMO 254 Nuts Suppliers & Exporters
Aurum Overseas is a trusted SMO 254 Nuts Supplier and Exporter. Made with 6% molybdenum super-austenitic stainless steel (UNS S31254 / 1.4547), these 6Mo Alloy Nuts offer a high pitting resistance value (PREN >= 42) to withstand harsh chloride, seawater, and chemical bleaching environments.
Manufactured to ASTM A479 and ASTM A240 standards, UNS S31254 Nuts deliver double the yield strength of standard 300-series stainless steels. As a certified exporter, Aurum Overseas supplies fully tested bolting solutions across the USA, Germany, UK, UAE, Saudi Arabia, and Qatar.
SMO 254 Nuts Specifications
| Parameter | Specification / Technical Range |
|---|---|
| Material Grade | SMO 254 / 6% Moly / UNS S31254 |
| UNS Number | UNS S31254 |
| Werkstoff Number | 1.4547 |
| Manufacturing Standards | ASTM A479, ASME SA479, ASTM A240, DIN 934, ISO 4032, BS |
| Size Range | M3 to M100 | 3/16" to 4" | Custom Sizes Available |
| Length Range | 3 mm to 200 mm | Custom Lengths Available |
| Thread Configuration | ASME B1.1 2A/3A - 2B/3B Unified (UNC, UNF) & B1.13M 6h-6G Metric |
| Special Fastener Formats | SMO 254 Hex Head Nuts, SMO 254 Square Nuts, SMO 254 T Nuts, SMO 254 Eye Nuts |
| Surface Finishes | Bright Polished, Passivated, Solution Annealed, Pickled |
| Certifications | EN 10204 3.1 Material Test Certificate, NACE MR0175 / ISO 15156 Compliant |
What are Stainless Steel SMO 254 Nuts?
SMO 254 (UNS S31254 / 1.4547) nuts are 6% molybdenum super-austenitic fasteners alloyed with high levels of chromium, nitrogen, and copper. Designed as a cost-effective alternative to nickel-base alloys, these high-molybdenum nuts offer superior resistance to chloride-induced pitting, crevice corrosion, and stress corrosion cracking in high-salinity industrial fluids.
SMO 254 Technical Properties & Composition
The chemical composition and mechanical properties of SMO 254 are precisely engineered to deliver maximum resistance to chloride pitting and crevice corrosion, with superior yield strength and dimensional stability in aggressive marine, bleaching, and seawater service environments.
Chemical Composition of SMO 254 Fasteners (%)
| Element | Percentage |
|---|---|
| Carbon (C) | 0.02 max |
| Manganese (Mn) | 1.0 max |
| Silicon (Si) | 0.8 max |
| Phosphorus (P) | 0.03 max |
| Sulfur (S) | 0.01 max |
| Chromium (Cr) | 19.5 - 20.5 |
| Molybdenum (Mo) | 6.0 - 6.5 |
| Nickel (Ni) | 17.5 - 18.5 |
| Copper (Cu) | 0.5 - 1.0 |
| Nitrogen (N) | 0.18 - 0.22 |
Mechanical Properties of SMO 254 Nuts
| Property / Parameter | Value / Technical Range |
|---|---|
| Density | 8.0 g/cm³ |
| Melting Point | 1320°C - 1390°C (2410°F - 2535°F) |
| Tensile Strength | 650 MPa min |
| Yield Strength (0.2% Offset) | 300 MPa min |
| Elongation (% in 50mm) | 35% min |
Equivalent Grades of SMO 254 Fasteners
| Standard | Werkstoff Nr. | UNS | SIS | EN |
|---|---|---|---|---|
| SMO 254 | 1.4547 | S31254 | 2378 | X1CrNiMoCuN20-18-7 |
Why Industries Prefer SMO 254 Series Nuts
Marine and chemical process engineers specify 6Mo Alloy Nuts when standard stainless steel grades fail due to pitting and crevice corrosion in seawater.
With a high pitting resistance value (PREN >= 42) achieved through 6% molybdenum and nitrogen additions, UNS S31254 Nuts resist corrosion in hot, chlorinated seawater and pulp bleaching plants. As a certified SMO 254 Nuts Supplier, Aurum Overseas supplies these high-performance fasteners to reverse osmosis plants, offshore oil platforms, and chemical processing facilities worldwide.
Types of SMO 254 Series Nuts
Aurum Overseas supplies a comprehensive range of super-austenitic nut configurations manufactured according to standard DIN, ASME, and ISO dimensional tolerances for multiple engineering assemblies.
SMO 254 Hex Head Nuts
SMO 254 Square Nuts
SMO 254 Lock Nuts
SMO 254 Eye Nuts
SMO 254 Wing Nuts
SMO 254 T Nuts
SMO 254 Panel Nuts
SMO 254 Coupling Nuts
SMO 254 Heavy Hex Nuts
Key Advantages of 6Mo Alloy Nuts
High Pitting Resistance (PREN >= 42)
6% Molybdenum content provides protection against localized pitting in brackish water and seawater.
Resists Crevice Corrosion
Nitrogen and chromium additions maintain tight passive surface protection inside narrow fastener threads and flange gaps.
Higher Structural Yield Strength
Nitrogen alloying increases yield strength (300 MPa min), almost double that of conventional 316L fasteners.
Cost Alternative to Nickel Alloys
Delivers pitting performance comparable to Alloy 625 at a lower cost for seawater applications.
High Resistance to Acid Halides
Excellent stability in halide-rich solutions, tall oil distillation columns, and flue gas desulfurization (FGD) scrubbers.
Key Applications of UNS S31254 Series Nuts
Our SMO 254 nuts are deployed globally in desalination plants, offshore oil and gas platforms, pulp and paper bleach processing, and aggressive marine engineering environments.
| Industry Sector | Primary Fastener Application |
|---|---|
| Desalination Plants | High-pressure seawater reverse osmosis (SWRO) pump casings and piping flanges |
| Offshore Oil & Gas | Subsea manifolds, riser bolting, and seawater cooling systems |
| Pulp & Paper Processing | Bleach plant washers, vats, press rolls, and chlorine dioxide stage equipment |
| Marine Engineering | Propeller shaft hardware, hull penetrations, and marine scrubber flanges |
| Chemical Processing | Handling equipment for organic acids, halogens, and high-chloride process streams |
SMO 254 Nuts vs SS 316L Nuts
When selecting the ideal fastener grade for aggressive marine and chemical environments, understanding the performance differences between SMO 254 and SS 316L is essential.
| Comparison Factor | SMO 254 Nuts | SS 316L Nuts |
|---|---|---|
| Alloy Family | Super-Austenitic (6% Moly) | Standard Austenitic |
| Molybdenum Content | 6.0% - 6.5% | 2.0% - 2.5% |
| Pitting Resistance (PREN) | High resistance to seawater (PREN >= 42) | Moderate resistance (PREN approx. 25) |
| Yield Strength (0.2% Offset) | 300 MPa min | 220 MPa min |
| Primary Suitability | Chlorinated seawater, bleaching acids, and brine | Mild chemical exposure and indoor/urban atmospheres |
| Detailed Specifications | Current Page | View SS 316L Nuts Specs → |
Quality Testing & Inspection
Aurum Overseas follows strict quality control guidelines to ensure all products delivered as an SMO 254 Nuts Supplier and SMO 254 Nuts Exporter perform reliably in harsh marine environments.
| Test / Inspection Standard | Technical Verification Scope |
|---|---|
| Positive Material Identification (PMI) | XRF testing verifying 6% Mo, 19.5-20.5% Cr, and 17.5-18.5% Ni content |
| Pitting Corrosion Resistance Testing | ASTM G48 Method A testing confirming crevice and pitting corrosion immunity |
| Dimensional Inspection | Thread pitch, profile, and concentricity verification per ASME B18.2.2 |
| Mechanical Strength Verification | Tensile, yield offset, and elongation testing to certified minimums |
| Certifications | Full heat traceability with EN 10204 3.1 Material Test Certificates |
Global Export Markets
As an international SMO 254 Nuts Exporter, Aurum Overseas supplies securely packaged, export-ready fasteners to project sites worldwide.
USA
Canada
Mexico
Germany
United Kingdom
France
Italy
Netherlands
Belgium
Spain
Poland
UAE
Saudi Arabia
Qatar
Kuwait
Oman
Bahrain
Frequently Asked Questions
6Mo Alloy Nuts contain 6.0% to 6.5% Molybdenum and added Nitrogen, yielding a PREN >= 42. This provides far superior protection against seawater pitting and double the yield strength compared to standard 316L nuts.
Yes, UNS S31254 nuts maintain a fully super-austenitic structure and remain non-magnetic in annealed and machined conditions.
Aurum Overseas manufactures SMO 254 Hex Head Nuts, SMO 254 Square Nuts, SMO 254 T Nuts, and heavy forged SMO 254 Eye Nuts tailored to engineering specifications.
Yes, SMO 254 was originally formulated to withstand harsh chlorine dioxide and hypochlorite bleaching stages in pulp and paper processing.
Yes, Aurum Overseas regularly exports certified SMO 254 fasteners to industrial processing hubs across the USA, European markets (Germany, UK, France), and GCC nations (UAE, Saudi Arabia, Qatar).
Contact Aurum Overseas
Aurum Overseas provides rapid pricing, complete mill test certificates, and global export shipping for high-molybdenum super-austenitic fasteners.
Contact our technical sales engineers today for immediate assistance.