Both Monel 400 and K500 flanges are nickel-copper alloys with excellent corrosion resistance, but Monel K500 has higher strength and hardness due to age hardening. Monel 400 is a solid solution strengthened alloy, while Monel K500 is a precipitation strengthened alloy. K500 also has higher resistance to sour gas environments and maintains its strength in corrosive conditions.

What is the ASTM standard for Monel 400 flanges?

ASTM B564 Monel 400 slip-on flanges allow seamless pipes to be slipped on, simplifying positioning. Flanges are available in two types: welded flanges and threaded flanges. Monel 400 alloy threaded flanges are suitable for pipes with threads.
Equivalent Grades of Monel 400/K500 Flanges
| STANDARD | WERKSTOFF NR. | UNS | JIS | BS | GOST | AFNOR | EN |
| Monel 400 | 2.4360 | N04400 | NW 4400 | NA 13 | МНЖМц 28-2,5-1,5 | NU-30M | NiCu30Fe |
| Monel K500 | 2.4375 | N05500 | - | - | - | - | - |
Chemical Composition of Monel 400/K500 Flanges
| Grade | Ni | Fe | C | Mn | Si | Cu | Al | Ti | S |
| 400 | 63.0- 70.00 max | 2.50 max | 0.3 max | 2.00 max | 0.50 max | Remainder | - | - | 0.024 max |
| K500 | 63.0 min | 05 - 2 | 0.25 max | 1.5 max | 0.5 max | 27.0 - 33.0 | 2.3 - 3.15 | 0.35 - 0.85 | 0.010 max |
Mechanical Properties of Monel 400/K500 Flanges
| Element | Density | Melting Point | Tensile Strength | Yield Strength (0.2%Offset) | Elongation |
| Monel 400 | 8.8 g/cm3 | 1350 °C (2460 °F) | Psi – 80,000 , MPa – 550 | Psi – 35,000 , MPa – 240 | 40 % |
| Monel K500 | 8.44 g/cm3 | 1350 °C (2460 °F) | Psi – 160000 , MPa – 1100 | Psi – 115000 , MPa – 790 | 20 % |
Gnee Steel Dimensions Of Monel 400/K500 Flanges

| Nom. Pipe Size |
O | T | R | X | No./Dia. of Holes | Bolt Circle Dia. |
L2 | H | B2 | L | B | r | L3 | B3 | D |
| 1/2 | 3.5 | 0.44 | 1.38 | 1.19 | 4-0.62 | 2.38 | 1.88 | 0.84 | 0.62 | 0.62 | 0.88 | 0.12 | 0.62 | 0.9 | 0.38 |
| 3/4 | 3.88 | 0.5 | 1.69 | 1.5 | 4-0.62 | 2.75 | 2.06 | 1.05 | 0.82 | 0.62 | 1.09 | 0.12 | 0.62 | 1.11 | 0.44 |
| 1 | 4.25 | 0.56 | 2 | 1.94 | 4-0.62 | 3.12 | 2.19 | 1.32 | 1.05 | 0.69 | 1.36 | 0.12 | 0.69 | 1.38 | 0.5 |
| 1-1/4 | 4.62 | 0.62 | 2.5 | 2.31 | 4-0.62 | 3.5 | 2.25 | 1.66 | 1.38 | 0.81 | 1.7 | 0.19 | 0.81 | 1.72 | 0.56 |
| 1-1/2 | 5 | 0.68 | 2.88 | 2.56 | 4-0.62 | 3.88 | 2.44 | 1.9 | 1.61 | 0.88 | 1.95 | 0.25 | 0.88 | 1.97 | 0.62 |
| 2 | 6 | 0.75 | 3.62 | 3.06 | 4-0.75 | 4.75 | 2.5 | 2.38 | 2.07 | 1 | 2.44 | 0.31 | 1 | 2.46 | 0.69 |
| 2-1/2 | 7 | 0.88 | 4.12 | 3.56 | 4-0.75 | 5.5 | 2.75 | 2.88 | 2.47 | 1.12 | 2.94 | 0.31 | 1.12 | 2.97 | 0.75 |
| 3 | 7.5 | 0.94 | 5 | 4.25 | 4-0.75 | 6 | 2.75 | 3.5 | 3.07 | 1.19 | 3.57 | 0.38 | 1.19 | 3.6 | 0.81 |
| 3-1/2 | 8.5 | 0.94 | 5.5 | 4.81 | 8-0.75 | 7 | 2.81 | 4 | 3.55 | 1.25 | 4.07 | 0.38 | 1.25 | 4.1 | 0.88 |
| 4 | 9 | 0.94 | 6.19 | 5.31 | 8-0.75 | 7.5 | 3 | 4.5 | 4.03 | 1.31 | 4.57 | 0.44 | 1.31 | 4.6 | 0.94 |
| 5 | 10 | 0.94 | 7.31 | 6.44 | 8-0.88 | 8.5 | 3.5 | 5.56 | 5.05 | 1.44 | 5.66 | 0.44 | 1.44 | 5.69 | 0.94 |
| 6 | 11 | 1 | 8.5 | 7.56 | 8-0.88 | 9.5 | 3.5 | 6.63 | 6.07 | 1.56 | 6.72 | 0.5 | 1.56 | 6.75 | 1.06 |
| 8 | 13.5 | 1.12 | 10.62 | 9.69 | 8-0.88 | 11.75 | 4 | 8.63 | 7.98 | 1.75 | 8.72 | 0.5 | 1.75 | 8.75 | 1.25 |
| 10 | 16 | 1.19 | 12.75 | 12 | 12-1.00 | 14.25 | 4 | 10.75 | 10.02 | 1.94 | 10.88 | 0.5 | 1.94 | 10.92 | 1.31 |
| 12 | 19 | 1.25 | 15 | 14.38 | 12-1.00 | 17 | 4.5 | 12.75 | 12 | 2.19 | 12.88 | 0.5 | 2.19 | 12.92 | 1.56 |
| 14 | 21 | 1.38 | 16.25 | 15.75 | 12-1.12 | 18.75 | 5 | 14 | 13.25 | 2.25 | 14.14 | 0.5 | 3.12 | 14.18 | 1.63 |
| 16 | 23.5 | 1.44 | 18.5 | 18 | 16-1.12 | 21.25 | 5 | 16 | 15.25 | 2.5 | 16.16 | 0.5 | 3.44 | 16.19 | 1.75 |
| 18 | 25 | 1.56 | 21 | 19.88 | 16-1.25 | 22.75 | 5.5 | 18 | 17.25 | 2.69 | 18.18 | 0.5 | 3.81 | 18.2 | 1.94 |
| 20 | 27.5 | 1.69 | 23 | 22 | 20-1.25 | 25 | 5.69 | 20 | 19.25 | 2.88 | 20.2 | 0.5 | 4.06 | 20.25 | 2.13 |
| 22 | 29.5 | 1.81 | 25.25 | 24.25 | 20-1.38 | 27.25 | 5.88 | 22 | 21.25 | 3.13 | 22.22 | 0.5 | 4.25 | 22.25 | 2.38 |
| 24 | 32 | 1.88 | 27.25 | 26.12 | 20-1.38 | 29.5 | 6 | 24 | 23.25 | 3.25 | 24.25 | 0.5 | 4.38 | 24.25 | 2.5 |
Conclusion
Gnee Steel is a supplier of Monel 400 Flange And K500 Flange, covering tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. We work with steel mills to provide customers with 625 alloy, and its products meet or exceed many leading industry standards, including ASTM, ASME, SAE, AMS, ISO, DIN, EN and BS standards.
Gnee Steel stocks and sells Monel 400 Flange And K500 Flange tubes, pipes, plates, strips, plates, round bars, flat bars, forged billets, hexagons, wire and extrusions. You are welcome to contact us for a quote at any time at ss@gneesteel.com





