Corrosion-Resistant Nickel-Copper Alloy 400 Buttweld, Forged Socket Weld & Threaded (NPT) Pipe Fittings
Om Export India Pvt Ltd is a premier manufacturer, stockist, and global supplier of high-integrity Monel 400 Pipe Fittings (ASTM B366 UNS N04400 / Werkstoff 2.4360 / Alloy 400). Monel 400 is a ductile, solid-solution nickel-copper alloy containing a minimum of 63% Nickel and 28% to 34% Copper. It provides outstanding resistance to corrosive media across high-velocity seawater, hydrofluoric acid, sulfuric acid, boiling caustic alkalines, and dry chlorine gases.
Our complete manufacturing range encompasses ASME B16.9 factory-made wrought buttweld fittings, ASME B16.11 high-pressure forged socket weld and screwed threaded fittings (Class 2000, 3000, 6000, and 9000 lbs), long radius induction pipe bends (1D to 10D), and high-precision double ferrule instrumentation compression tube fittings. Designed to meet ASTM B366 WPNC/CRNC specifications and NACE MR0175 sour service requirements, our fittings maintain structural ductility and mechanical toughness from sub-zero cryogenic temperatures up to elevated service temperatures of 1000°F (538°C).
| Specification Parameter | Standard Specification / Technical Value |
|---|---|
| Buttweld Size Range | 1/2" NB to 24" NB (DN15 to DN600) — Seamless & Welded |
| Forged Socket Weld & Screwed Range | 1/8" NB to 4" NB (DN6 to DN100) |
| Wall Thickness & Schedules | SCH 10S, SCH 40S, SCH 80S, SCH 160, SCH XXS (Per ASME B36.19M / B36.10M) |
| Pressure Classes (Forged Fittings) | Threaded: 2000 lbs, 3000 lbs, 6000 lbs | Socket Weld: 3000 lbs, 6000 lbs, 9000 lbs |
| Bending Radii (Pipe Bends) | R = 1D, 1.5D (LR), 2D, 3D, 5D, 6D, 8D, 10D, or Custom Radius |
| Fitting Construction Classes | Class S (Seamless), Class W (Welded + NDE), Class WX (100% Radiography), Class WU (100% Ultrasonic) |
| Thread Configurations | NPT (ANSI/ASME B1.20.1), BSPT (BS 21), BSPP (ISO 228) |
| Testing & Compliance | EN 10204 Type 3.1 & 3.2, NACE MR0175 / ISO 15156, 100% PMI Spectro, Hydrostatic, DPI / UT |
| Nominal Pipe Size (NPS) | Outside Diameter (OD mm / in.) | 90° Elbow Center to End (ASME B16.9 mm) | Tee Center to End (ASME B16.9 mm) | Class 3000 Socket Weld Socket Bore (mm) | Class 3000 Threaded Hex Nipple Length (mm) |
|---|---|---|---|---|---|
| 1/4" NB | 13.72 mm (0.540") | 25.4 mm (1.00") | 25.4 mm (1.00") | 14.2 mm | 35.0 mm |
| 1/2" NB | 21.34 mm (0.840") | 38.1 mm (1.50") | 25.4 mm (1.00") | 21.8 mm | 48.0 mm |
| 3/4" NB | 26.67 mm (1.050") | 38.1 mm (1.50") | 28.6 mm (1.12") | 27.2 mm | 52.0 mm |
| 1" NB | 33.40 mm (1.315") | 38.1 mm (1.50") | 38.1 mm (1.50") | 33.9 mm | 60.0 mm |
| 1-1/4" NB | 42.16 mm (1.660") | 47.6 mm (1.88") | 47.6 mm (1.88") | 42.7 mm | 66.0 mm |
| 1-1/2" NB | 48.26 mm (1.900") | 57.2 mm (2.25") | 57.2 mm (2.25") | 48.8 mm | 68.0 mm |
| 2" NB | 60.33 mm (2.375") | 76.2 mm (3.00") | 63.5 mm (2.50") | 61.2 mm | 78.0 mm |
| 2-1/2" NB | 73.03 mm (2.875") | 95.3 mm (3.75") | 76.2 mm (3.00") | 73.9 mm | 90.0 mm |
| 3" NB | 88.90 mm (3.500") | 114.3 mm (4.50") | 85.7 mm (3.38") | 89.8 mm | 95.0 mm |
| 4" NB | 114.30 mm (4.500") | 152.4 mm (6.00") | 104.8 mm (4.12") | 115.5 mm | 110.0 mm |
| 6" NB | 168.28 mm (6.625") | 228.6 mm (9.00") | 142.9 mm (5.62") | — | — |
| 8" NB | 219.08 mm (8.625") | 304.8 mm (12.00") | 177.8 mm (7.00") | — | — |
| 10" NB | 273.05 mm (10.750") | 381.0 mm (15.00") | 215.9 mm (8.50") | — | — |
| 12" NB | 323.85 mm (12.750") | 457.2 mm (18.00") | 254.0 mm (10.00") | — | — |
| Element | ASTM B366 / UNS N04400 (%) | DIN 2.4360 / NiCu30Fe (%) |
|---|---|---|
| Nickel (Ni + Co) | 63.00 Min | 63.00 Min |
| Copper (Cu) | 28.00 – 34.00 | 28.00 – 34.00 |
| Iron (Fe, Max) | 2.50 | 2.50 |
| Manganese (Mn, Max) | 2.00 | 2.00 |
| Carbon (C, Max) | 0.30 | 0.15 |
| Silicon (Si, Max) | 0.50 | 0.50 |
| Sulfur (S, Max) | 0.024 | 0.020 |
| Material Temper / Condition | Tensile Strength (MPa / ksi) | Yield Strength 0.2% Offset (MPa / ksi) | Elongation in 2 in. (%) | Hardness (Rockwell / Brinell) |
|---|---|---|---|---|
| Annealed (Wrought Fitting) | 480 – 600 MPa (70 – 87 ksi) | 195 – 345 MPa (28 – 50 ksi) | 35% – 50% | 65 – 80 HRB (110 – 150 HBW) |
| Stress Relieved (300°C–320°C) | 585 – 750 MPa (85 – 109 ksi) | 380 – 585 MPa (55 – 85 ksi) | 20% – 35% | 85 – 95 HRB (160 – 210 HBW) |
| Physical Density & Melting Point | Density: 8.80 g/cm³ (0.318 lb/in³) | Melting Point: 1350°C (2460°F) | Thermal Exp: 13.9 µm/m·°C | |
| Elastic & Rigidity Modulus | Modulus of Elasticity: 105 – 120 kN/mm² | Modulus of Rigidity: 65.3 kN/mm² | Service Temp: -200°C to +538°C | |
| Standard Designation | Governing Body | Scope & Product Type |
|---|---|---|
| ASTM B366 / ASME SB366 | ASTM / ASME | Factory-Made Wrought Nickel and Nickel Alloy Fittings (WPNC / CRNC) |
| ASTM B564 / ASME SB564 | ASTM / ASME | Nickel Alloy Forgings (Socket Weld, Threaded Fittings, and Flanges) |
| ASME B16.9 / ASME B16.28 | ASME | Factory-Made Wrought Buttwelding Fittings and Short Radius Bends |
| ASME B16.11 | ASME | Forged Fittings, Socket-Welding and Threaded (Class 2000, 3000, 6000, 9000) |
| MSS SP-43 / MSS SP-79 / MSS SP-83 | MSS Standards | Wrought Buttweld Fittings (MSS SP-43), Socket Weld Reducer Inserts (SP-79), Pipe Unions (SP-83) |
| MSS SP-95 / MSS SP-97 | MSS Standards | Swage(d) Nipples and Bull Plugs (SP-95), Integrally Reinforced Forged Branch Outlets / Olets (SP-97) |
| BS 3799 / DIN 2.4360 | British & German Standards | Steel and Nickel Alloy Screwed and Socket-Welding Fittings for Petroleum and Chemical Industries |
| NACE MR0175 / ISO 15156 | NACE / ISO | Petroleum and Natural Gas Industries — Materials for use in H2S-containing environments |
Monel 400 pipe fittings are widely used in mission-critical marine, petrochemical, and heavy process installations:
Q1: What are the differences between ASTM B366 WPNC and CRNC Monel 400 fittings?
ASTM B366 WPNC refers to factory-made wrought Monel 400 fittings conforming to ASME B16.9 / B16.11 pressure vessel codes with mandatory radiography or ultrasonic non-destructive testing for welded variants. CRNC refers to corrosion-resistant wrought fittings produced to MSS SP-43 dimensional and pressure tolerances for lighter low-pressure piping systems.
Q2: Why is Monel 400 the standard alloy for hydrofluoric acid (HF) alkylation fittings?
Monel 400 provides high resistance to non-aerated hydrofluoric acid at all concentrations up to the boiling point, preventing catastrophic hydrogen-assisted stress corrosion cracking and localized pitting in severe acid service.
Q3: Can Monel 400 fittings be welded directly to stainless steel or carbon steel pipes?
Yes, Monel 400 fittings can be welded to carbon steel, stainless steel, and other nickel alloys using AWS ERNiCu-7 (Monel 60) or AWS ENiCu-7 (Monel 190) welding consumables with proper pre-weld solvent degreasing to prevent sulfur/lead embrittlement.
Q4: What non-destructive testing is performed on Monel 400 forged and buttweld fittings?
Fittings undergo 100% Positive Material Identification (PMI) by direct-reading spectrograph, Dye Penetrant Inspection (DPI) on machined and formed surfaces, 100% Radiography (RT) or Ultrasonic Testing (UT) on welded seams, and hydrostatic pressure testing.
Contact OM Export India for pricing, technical support, stock availability and export enquiries.