Engineering Excellence
High-Performance Super Duplex Stainless Steel Fasteners Exporter
Stud Bolt India is an ISO 9001:2015 certified manufacturer and stockist of high-tensile, corrosion-resistant Super Duplex Steel Fasteners including UNS S32750 (Super Duplex 2507), UNS S32760 (Zeron 100), and UNS S32950. Designed specifically for critical service conditions, our Super Duplex bolting products offer high mechanical yield strength (> 550 MPa) coupled with superior resistance to pitting, crevice corrosion, and stress corrosion cracking in aggressive halide environments.
Each lot of Super Duplex studs, hex nuts, socket cap screws, washers, and threaded rods undergoes rigorous quality control including 100% Positive Material Identification (PMI), ultrasonic testing, microstructural phase balance inspection (50:50 austenite-ferrite ratio), and mechanical proof load testing. Certified with EN 10204 3.1 Mill Test Certificates, our products strictly adhere to ASTM A193, ASTM A194, ASTM F593, ASTM F594, ASME B18.2.1, ASME B18.2.2, and DIN standards for global marine, offshore, petrochemical, and power generation engineering.
Product Lineup
Comprehensive Range of Super Duplex Fasteners
UNS S32750 / S32760 Super Duplex Stud Bolts
Fully threaded and double-end studs designed for high-pressure ASME B16.5 flange connections in offshore platforms and subsea pipelines.
ASTM F593 / ASME B18.2.1 Super Duplex Hex Bolts
Precision hot-forged and CNC-machined hex head bolts providing exceptional yield strength for structural marine applications.
ASTM A194 Grade 8M / 8T Super Duplex Nuts
Heavy hex and standard hex nuts machined to tight tolerances to ensure thread compatibility and high galling resistance under extreme loads.
DIN 912 / ISO 4762 Super Duplex Screws
Socket head cap screws, countersunk screws, and set screws engineered for high-stress machinery operating in corrosive media.
ASTM F436 / DIN 125 Super Duplex Washers
Flat plain washers, spring lock washers, and heavy-duty load distribution washers to protect joint surface integrity.
DIN 975 / DIN 976 Super Duplex Threaded Rods
Continuous metric and imperial threaded rods available up to 5 meters in length, tailored for custom chemical vessel assemblies.
Technical Reference
Super Duplex Fasteners Specifications & Standards
| Feature / Standard | Technical Details |
| Material Grades | UNS S32750 (Duplex 2507, 1.4410), UNS S32760 (Zeron 100, 1.4501), UNS S32950 |
| Manufacturing Standards | ASTM A193, ASTM A194, ASTM F593, ASTM F594, ASTM A479, ASME B18.2.1, ASME B18.2.2, DIN 931, DIN 933, DIN 934, ISO 4014, ISO 4017 |
| Size Range | Metric: M10 to M100 | Imperial: 3/8" to 4" (Custom sizes manufactured to drawing) |
| Thread Pitch | UNC, UNF, UN8, Metric Coarse, Metric Fine (Class 2A/2B, 6g/6H precision fitting) |
| Length | Up to 5,000 mm (5 Meters) cut-to-length studs & rods |
| Surface Coatings | PTFE / Xylan Coating, Hot-Dip Galvanized (HDG), Electropolished, Passivated, Cadmium Plated |
| Testing & Certification | EN 10204 3.1 MTC, PMI Test, Hardness Test, Tensile & Proof Load, Impact Test (-40°C), Ferrite Count (ASTM E562), Microstructure Analysis |
Material Science
Chemical Composition & Mechanical Properties
Chemical Composition (Weight %)
| Grade | C | Mn | Si | P | S | Cr | Mo | Ni | N | Other |
| UNS S32750 (2507) | 0.030 max | 1.20 max | 0.80 max | 0.035 max | 0.020 max | 24.0 - 26.0 | 3.0 - 5.0 | 6.0 - 8.0 | 0.24 - 0.32 | - |
| UNS S32760 (Zeron 100) | 0.05 max | 1.00 max | 1.00 max | 0.030 max | 0.010 max | 24.0 - 26.0 | 3.0 - 4.0 | 6.0 - 8.0 | 0.20 - 0.30 | Cu: 0.5-1.5, W: 0.5-1.0 |
Mechanical Performance Data
| Grade | Tensile Strength (MPa) | 0.2% Yield Strength (MPa) | Elongation (%) | Hardness (Brinell / HRC) | PREN Value |
| Super Duplex UNS S32750 | 750 - 1000 | ≥ 550 | ≥ 15% | 310 max HBW / 32 HRC | ≥ 42.0 |
| Super Duplex UNS S32760 | 750 - 1000 | ≥ 550 | ≥ 25% | 310 max HBW / 32 HRC | ≥ 41.5 |
Global Application
Key Industries Utilizing Super Duplex Fasteners
Offshore Oil & Gas
Subsea Christmas trees, risers, manifolds, and structural flange bolting exposed to sour crude and high chloride seawater.
Desalination Plants
High-pressure reverse osmosis pumps, evaporators, and seawater intake systems demanding total immunity to pitting.
Chemical Processing
Handling organic and inorganic acids, chlor-alkali environments, and nitric acid process piping assemblies.
Marine Engineering
Propeller shafts, marine hardware, rudder assemblies, and naval equipment operating in warm tropical ocean waters.
Extended Product Range
Other Specialized Super Duplex Fastener Variants
- Super Duplex Steel J-Bolts & U-Bolts
- Super Duplex Heavy Hexagonal Bolts
- SDSS Lag Bolts & Timber Screws
- Super Duplex Nylock & Self-Locking Nuts
- Super Duplex Steel Square & Flange Nuts
- Super Duplex Spring & Wave Washers
- ASME SF594 Concrete & Anchor Bolts
- Super Duplex Continuous Threaded Studs
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