Monel 400 Flanges are made to ASTM B564 / ASME SB564 UNS N04400 for seawater and HF acid service. They are supplied in every common flange type and facing to ASME B16.5, B16.47 and the main EN, DIN, BS and JIS standards.
Raaj Fittings manufactures Monel 400 flanges in-house at our two plants in India, from ½" to 60" and in Class 150 to Class 2500, 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 N04400 |
|---|---|
| Dimensional standards | ASME B16.5 (½" to 24"), ASME B16.47 Series A and B (26" to 60"), EN 1092-1, DIN, BS 4504, JIS B2220 |
| Pressure class | ASME Class 150, 300, 600, 900, 1500 and 2500; PN 6 to PN 400 |
| Facing | Raised Face (RF), Flat Face (FF), Ring Type Joint (RTJ), Male & Female, Tongue & Groove |
| Certification | EN 10204 3.1 mill test certificate as standard; EN 10204 3.2 on request |
Alloy 400 (UNS N04400) is a nickel-copper alloy with about 65% nickel and 30% copper. It is renowned for resisting fast-flowing seawater, hydrofluoric acid and alkalis, and it keeps good toughness from cryogenic temperatures to about 480 °C.
| Element, % | N04400 |
|---|---|
| Nickel (Ni, incl. Co) | 63.0 min |
| Copper (Cu) | 28.0 – 34.0 |
| Iron (Fe) | 2.5 max |
| Manganese (Mn) | 2.0 max |
| Carbon (C) | 0.3 max |
| Silicon (Si) | 0.5 max |
| Sulphur (S) | 0.024 max |
Mechanical properties are as required by the ordered ASTM specification and are reported on the mill test certificate.
| UNS | Werkstoff Nr. | EN / DIN | Other |
|---|---|---|---|
| N04400 | 2.4360 | NiCu30Fe | Monel® 400 |
Nickel alloy flanges are forged from certified bar or billet and machined; their high cost means flange type and facing should be chosen carefully, and lap joint flanges with Monel 400 stub ends are sometimes used to save material.
Every heat is PMI-verified and its chemistry and mechanical properties are confirmed against the material specification before the flanges 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.
Alloy 400 is one of the few materials with good resistance to hydrofluoric acid, so it is the standard choice for piping and fittings in refinery HF alkylation units.
Yes, especially flowing seawater. In stagnant seawater, crevices and deposits can cause pitting, so design and maintenance should avoid stagnant conditions.
We make Monel 400 Flanges from ½" to 24" to ASME B16.5 and from 26" to 60" to ASME B16.47 Series A and B, in Class 150 to 2500, and to EN 1092-1, DIN, BS and JIS standards in PN ratings.
Every order is supplied with EN 10204 3.1 mill test certificates showing heat chemistry and mechanical properties to ASTM B564 UNS N04400. EN 10204 3.2 certification and inspection by your nominated third-party agency are available on request.