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Okoye Nickel Alloys is a well-respected manufacturer and supplier of top-notch Super Duplex Steel Stud Bolts based in Kinshasa, Congo. They cater to a variety of industrial sectors with a focus on excellence and reliability. With a strong dedication to precision engineering and the use of high-quality raw materials, the company specializes in crafting durable and corrosion-resistant fastening solutions that can handle extreme service conditions. Okoye Nickel Alloys adheres to international standards and employs advanced manufacturing technologies, ensuring outstanding performance in demanding applications across the petrochemical, marine, chemical processing, and offshore industries. Their Super Duplex Steel Stud Bolts are known for their exceptional strength, long service life, and remarkable resistance in aggressive and high-pressure environments, making them a go-to choice for industries around the globe.
Super Duplex Steel Stud Bolts are made up mainly of chromium (24–26%), nickel (6–8%), molybdenum (3–5%), nitrogen, and a few trace elements. This unique blend creates a balanced duplex microstructure of austenite and ferrite, which is key to their impressive corrosion resistance, particularly against pitting, crevice corrosion, and chloride stress cracking. On the mechanical side, these bolts boast high tensile strength, outstanding yield strength, remarkable hardness, and excellent fatigue resistance, making them perfect for high-temperature and high-pressure applications. Their great weldability, structural stability, and toughness also make them a top choice for heavy-duty fastening tasks in tough marine and industrial settings.
| Specification | ASTM F593, F594, F1554 / ASME SF593, F594, F1554 |
| Standard | DIN : DIN 934, DIN 931, DIN 970, DIN 933 UTS : UNEF, NPT, UNC, UNS, UNF, NPTF ISO : JIS standards, ISO 4033, ISO 4032, ANSI – American National Standards Institute ASME B18.5 ANSI B 28.2.4 1M as per defined in ASME B16.5 standard Monel Monel® Alloy 400 Stud nuts length ANSI B 18.2.4 2M as per defined in ASME B18.2.2 Monel Alloy 400 Hex nuts |
| Size | M3 – M56 | 3/6″ to 2″ | Custom Sizes |
| Length | 3 mm to 200 mm | Custom Sizes |
| Dimensions | DIN 931, 933, 934, 7991, 976, 125, ASME B18.2.1, B18.3 |
| Form | Hex, Threading, Square, Round as per Gauge Etc. |
| Threads | Unless otherwise specified, the threads shall be rolled or cut and tapped horizontally or vertically |
| Threads available | UNF, BSW, BSF, METRIC, UNC, or as required |
| Threads Configuration | ASME B1.1 2A/3A – 2B/3B Inch Unified Threads and B1.13M 6h-6G Metric Coarse Threads |
| Certification | Dual Certified As per ASTM & ASME Codes |
| Test Certificate | As per EN 10204 / 3.1 Manufacturer Test Certificate, PED 97/23/EC Certified, Merkblatt AD 2000 W2 Certified |
| Raw materials Source | JSPL, Mukund Steel, Tata Steel, Dhamm Steel, Usha Martin,etc. |
| Packing | IN BULK: canton, pallet, Small Boxs / carton / pallet, or customer request |
| Surface Coating | Cadmium Coating Hot Dipped Galvanizing Coating Ptfe Coated Nickel Alloy 200 Fasteners Phosphate Coating Teflon Coating Xylon Coating Zinc Coating |
| Grade | C | N | P | Si | Mn | Mo | Fe | Cr | S | Ni |
| Super Duplex Steel Stud Bolts | 0.030 max | 0.24 – 0.32 | 0.035 max | 0.80 max | 1.20 ma | 3.0 – 5.0 | – | 24.0 – 26.0 | 0.020 max | 6.00 – 8.00 |
| Grade | Density | Melting Point | Yield Strength (0.2%Offset) | Tensile Strength | Elongation |
| Super Duplex Steel Stud Bolts | 7.8 g/cm3 | 1350 °C (2460 °F) | Psi – 80000 , MPa – 550 | Psi – 116000 , MPa – 800 | 15 % |
At Okoye Nickel Alloys, we take pride in being the largest supplier, exporter, and manufacturer of Super Duplex Steel Stud Bolts in Kinshasa, Congo, providing cutting-edge solutions for all your piping needs. Our state-of-the-art production plants are strategically located in the Congo, allowing us to maintain a vast inventory of over 16,000 tons of premium-quality materials readily available in stock. We are dedicated to delivering superior products and services, ensuring reliability and excellence for our global clientele.
Contact us to get a quick quote for your requirement.
Super Duplex Steel Stud Bolts are a go-to choice in industries that need fasteners tough enough to handle extreme corrosion and high-stress situations. You’ll often find them in offshore oil and gas platforms, subsea equipment, desalination plants, chemical processing units, and marine engineering projects. They play a vital role in heat exchangers, pumps, pressure vessels, valves, and pipeline systems, especially in refineries and power generation facilities. Thanks to their outstanding resistance to chloride-rich and acidic environments, they’re perfect for seawater cooling systems and shipbuilding. With their exceptional durability and mechanical strength, these bolts are the top pick for critical fastening applications where reliability and long-lasting performance are a must.