Hastelloy C276 Forged Fittings are made to ASTM B564 / ASME SB564 UNS N10276 for mixed acid and chlorine service. Socket weld and threaded fittings are dimensioned to ASME B16.11 for small-bore Hastelloy C276 piping.
Raaj Fittings manufactures Hastelloy C276 forged fittings in-house at our two plants in India, from ⅛" to 4" in Class 2000 to 9000, and exports them to EPC contractors, fabricators and stockists across the Middle East, Europe and the Americas, with full traceability and EN 10204 certificates.
| Material specification | ASTM B564 / ASME SB564 UNS N10276 |
|---|---|
| Dimensional standard | ASME B16.11; MSS SP-79, SP-83, SP-95 and SP-97 |
| Size range | ⅛" to 4" NPS |
| Pressure class | Socket weld: Class 3000, 6000, 9000. Threaded: Class 2000, 3000, 6000 |
| Threads | NPT to ASME B1.20.1; BSPT / BSPP to BS 21 / ISO 7-1 |
| Certification | EN 10204 3.1 mill test certificate as standard; EN 10204 3.2 on request |
Alloy C276 (UNS N10276) is a nickel-molybdenum-chromium alloy with tungsten, one of the most corrosion-resistant alloys used in process piping. Its very low carbon and silicon let it be welded without losing corrosion resistance at the welds.
| Element, % | N10276 |
|---|---|
| Molybdenum (Mo) | 15.0 – 17.0 |
| Chromium (Cr) | 14.5 – 16.5 |
| Iron (Fe) | 4.0 – 7.0 |
| Tungsten (W) | 3.0 – 4.5 |
| Cobalt (Co) | 2.5 max |
| Carbon (C) | 0.010 max |
| Silicon (Si) | 0.08 max |
| Manganese (Mn) | 1.00 max |
| Vanadium (V) | 0.35 max |
| Nickel (Ni) | Balance |
| Property | Hastelloy C276 |
|---|---|
| Tensile strength, min. | 690 MPa (100 ksi) |
| Yield strength (0.2%), min. | 283 MPa (41 ksi) |
| Elongation, min. | 40% |
| UNS | Werkstoff Nr. | EN / DIN | Other |
|---|---|---|---|
| N10276 | 2.4819 | NiMo16Cr15W | Hastelloy® C-276 |
In small-bore lines, the crevices of socket welds and threads are where corrosion starts. Hastelloy C276 forged fittings keep the same corrosion resistance as the run pipe at those points. Use matching filler for socket welds and an anti-seize sealant on threads, as nickel alloys gall easily.
| Pipe | Socket weld class | Threaded class |
|---|---|---|
| SCH 80 / XS | 3000 | 2000 |
| SCH 160 | 6000 | 3000 |
| XXS | 9000 | 6000 |
Every heat is PMI-verified and its chemistry and mechanical properties are confirmed against the material specification before the forged fittings are released. Each piece is marked with grade, size, rating and heat number for traceability to its EN 10204 3.1 mill test certificate. EN 10204 3.2 certification and inspection by the buyer's nominated third-party agency are available on request, as are PED 2014/68/EU compliance for European projects and IBR certification for Indian boiler applications.
Hastelloy is a trademark of Haynes International. Fittings are supplied to the ASTM specifications for UNS N10276, commonly called Alloy C276, which has the same chemistry.
C276 has higher molybdenum and tungsten and is preferred in strongly reducing acids, mixed acids and wet chlorine service; 625 is often chosen for seawater and high-strength applications.
Class 3000 socket weld fittings match SCH 80 pipe, Class 6000 matches SCH 160 and Class 9000 matches XXS. For threaded fittings, the matching classes are 2000, 3000 and 6000.
Every order is supplied with EN 10204 3.1 mill test certificates showing heat chemistry and mechanical properties to ASTM B564 UNS N10276. EN 10204 3.2 certification and inspection by your nominated third-party agency are available on request.