Monel 400 Bolts are high-performance fasteners manufactured from a nickel-copper alloy (UNS N04400) designed for extreme resistance to seawater, hydrofluoric acid, alkalis, and reducing environments. These bolts are widely used in marine engineering, chemical processing plants, and offshore oil & gas systems where conventional stainless steel grades fail due to chloride-induced corrosion.

Engineered to comply with standards such as ASTM B164 and applicable DIN/ISO dimensional norms, Monel 400 fasteners deliver stable mechanical strength across a wide temperature range from sub-zero conditions up to approximately 480°C. Their non-magnetic nature and exceptional resistance to stress corrosion cracking make them a preferred choice in critical industrial assemblies.
KK Fasteners supplies Monel 400 Bolts to global OEMs and EPC contractors, ensuring full material traceability and dimensional compliance for every batch shipped across international markets including the USA, UAE, Europe, and Southeast Asia.
| Parameter | Specification |
|---|---|
| Material | Monel 400 (Nickel-Copper Alloy UNS N04400) |
| Grade | ASTM B164 / ASME SB164 |
| Size Range | M6 to M100 / 1/4” to 4” |
| Thread Type | Metric (ISO), UNC, UNF |
| Standards | DIN, ISO, ASTM, BS, JIS |
| Tensile Strength | 480 – 620 MPa |
| Hardness | 70 – 90 HRB |
| Temperature Range | -200°C to 480°C |
| Surface Finish | Bright, Passivated, Black Oxide |
| Types | Hex Bolt, Heavy Hex Bolt, Stud Bolt, U-Bolt |
| Monel 400 | Ni | C | Al | Mn | Si | Fe | Cu | S | Co | Cr |
| 63.0 min | 0.3 max | 0.50 max | 2.0 max | 0.5 max | 1.0 – 2.5 | 28.0 – 34.0 | 0.02 max | – | – |
| Density | Melting Point | Yield Strength (0.2%Offset) | Tensile Strength | Elongation |
| 8.8 g/cm3 | 1350 °C (2460 °F) | Psi – 35,000 , MPa – 240 | Psi – 80,000 , MPa – 550 | 40 % |
| STANDARD | UNS | WERKSTOFF NR. | AFNOR | EN | JIS | BS | GOST |
| Monel 400 | N04400 | 2.4360 | NU-30M | NiCu30Fe | NW 4400 | NA 13 | МНЖМц 28-2,5-1,5 |
All measurements in millimeters
NOMINAL SIZE (D) |
BODY DIAMETER |
BOLT HEAD THICKNESS |
ACROSS THE FLATS |
ACROSS CORNERS |
||||
|---|---|---|---|---|---|---|---|---|
D (MAX) |
D (MIN) |
H (MAX) |
H (MIN) |
F (MAX) |
F (MIN) |
C (MAX) |
C (MIN) |
|
m10 |
10.00 |
9.78 |
6.63 |
6.17 |
17.00 |
15.73 |
18.48 |
17.77 |
m12 |
12.00 |
11.73 |
7.76 |
4.24 |
19.00 |
17.73 |
20.78 |
20.03 |
m14 |
14.00 |
13.73 |
9.09 |
8.51 |
22.00 |
20.67 |
24.25 |
23.35 |
m16 |
16.00 |
15.73 |
10.32 |
9.68 |
24.00 |
23.67 |
27.71 |
26.75 |
m20 |
20.00 |
19.67 |
12.88 |
12.12 |
30.00 |
29.16 |
34.64 |
32.95 |
m24 |
24.00 |
23.67 |
15.44 |
14.56 |
36.00 |
35.00 |
41.57 |
39.55 |
m30 |
30.00 |
29.67 |
19.48 |
17.92 |
46.00 |
45.00 |
53.12 |
50.85 |
m36 |
36.00 |
35.61 |
23.38 |
21.63 |
55.00 |
53.80 |
63.51 |
60.79 |
m42 |
42.00 |
41.38 |
26.97 |
25.03 |
65.00 |
62.90 |
75.06 |
71.71 |
m48 |
48.00 |
47.38 |
31.07 |
28.93 |
75.00 |
72.60 |
86.60 |
82.76 |
m56 |
56.00 |
55.26 |
36.2 |
33.80 |
85.00 |
82.20 |
98.15 |
93.71 |
m64 |
64.00 |
63.26 |
41.32 |
38.68 |
95.00 |
91.80 |
109.70 |
104.65 |
m72 |
72.00 |
71.26 |
46.45 |
43.55 |
105.00 |
101.40 |
121.24 |
115.60 |
m80 |
80.00 |
79.26 |
51.58 |
48.42 |
115.00 |
111.00 |
132.72 |
126.54 |
m90 |
90.00 |
89.13 |
57.74 |
54.26 |
130.00 |
125.50 |
150.11 |
143.07 |
m100 |
90.00 |
99.13 |
63.9 |
60.10 |
145.00 |
140.00 |
167.43 |
159.60 |
MM THREADS AS PER IS 1363/67 |
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|
Fasteners APPROXIMATE WEIGHT IN KGS FOR 100 NOS |
||||||||||
Monel 400 LENGTH |
D I A M E T E R |
|||||||||
M 5 |
M 6 |
M 8 |
M 10 |
M 12 |
M 14 |
M 16 |
M 18 |
M 20 |
M 22 |
|
| 16 mm | 0.448 | 0.743 | 1.590 | 3.211 | ||||||
| 20 mm | 0.598 | 0.812 | 1.711 | 3.411 | 4.892 | |||||
| 25 mm | 0.660 | 0.897 | 1.871 | 3.660 | 5.252 | 8.170 | ||||
| 30 mm | 0.737 | 1.010 | 2.070 | 3.912 | 5.574 | 9.690 | 10.707 | 18.657 | ||
| 35 mm | 0.804 | 1.120 | 2.271 | 4.223 | 5.974 | 10.000 | 11.416 | 16.026 | 19.608 | |
| 40 mm | 0.881 | 1.230 | 2.470 | 4.533 | 6.410 | 10.288 | 12.107 | 16.667 | 20.747 | |
| 45 mm | 0.958 | 1.340 | 2.671 | 4.840 | 6.859 | 10.504 | 12.821 | 17.241 | 21.739 | |
| 50 mm | 1.030 | 1.450 | 2.870 | 5.155 | 7.299 | 11.261 | 13.624 | 17.857 | 22.727 | 28.409 |
| 55 mm | 1.560 | 3.071 | 5.464 | 7.740 | 11.628 | 14.409 | 18.868 | 23.810 | 30.120 | |
| 60 mm | 1.670 | 3.270 | 5.774 | 8.183 | 12.255 | 15.244 | 20.000 | 25.126 | 32.051 | |
| 65 mm | 1.781 | 3.472 | 6.083 | 8.621 | 12.626 | 16.026 | 21.008 | 26.455 | 34.014 | |
| 70 mm | 1.890 | 3.671 | 6.394 | 9.058 | 12.987 | 16.835 | 22.124 | 27.778 | 35.461 | |
| 75 mm | 2.000 | 3.873 | 6.702 | 9.506 | 13.228 | 17.606 | 23.256 | 29.070 | 39.063 | |
| 80 mm | 2.111 | 4.072 | 7.013 | 10.000 | 13.889 | 18.248 | 24.510 | 30.303 | 40.000 | |
| 90 mm | 4.472 | 7.634 | 10.917 | 14.925 | 19.841 | 26.042 | 33.113 | 41.667 | ||
| 100 mm | 4.873 | 8.251 | 11.820 | 16.340 | 21.459 | 27.778 | 35.714 | 46.296 | ||
| 110 mm | 8.881 | 12.723 | 17.730 | 23.041 | 31.250 | 38.168 | 47.170 | |||
| 120 mm | 9.506 | 13.624 | 18.797 | 24.631 | 32.895 | 40.984 | 50.000 | |||
| 130 mm | 10.101 | 14.535 | 20.000 | 26.316 | 34.722 | 43.478 | 52.632 | |||
| 140 mm | 10.707 | 15.432 | 20.833 | 27.933 | 35.461 | 46.296 | 55.556 | |||
| 150 mm | 11.312 | 16.340 | 22.222 | 29.412 | 37.594 | 48.544 | 58.824 | |||
| 160 mm | 11.905 | 17.241 | 24.272 | 31.056 | 40.984 | 50.505 | 61.728 | |||
| 170 mm | 12.500 | 18.116 | 32.680 | 53.191 | 64.935 | |||||
| 180 mm | 13.123 | 19.011 | 26.882 | 34.247 | 55.556 | 67.568 | ||||
| 190 mm | 13.736 | 19.920 | 35.971 | 58.140 | 70.423 | |||||
| 200 mm | 14.327 | 20.833 | 29.586 | 37.594 | 49.020 | 60.976 | 73.529 | |||
| 220 mm | 15.528 | 22.624 | 40.650 | 65.789 | 79.365 | |||||
| 240 mm | 16.722 | 24.510 | 43.860 | 71.429 | 84.746 | |||||
| 250 mm | 17.301 | 25.381 | 45.455 | 74.627 | 87.719 | |||||
| 260 mm | 17.921 | 26.316 | 47.170 | 76.923 | 90.909 | |||||
| 280 mm | 19.157 | 28.090 | 50.505 | 81.967 | 98.039 | |||||
| 300 mm | 20.325 | 29.940 | 53.763 | 87.719 | 104.167 | |||||
| 320 mm | 31.646 | 56.818 | 92.593 | |||||||
| 340 mm | 33.557 | 60.241 | 98.039 | |||||||
| 360 mm | 35.211 | 63.291 | 104.167 | |||||||
| 380 mm | 37.037 | 66.667 | 108.696 | |||||||
| 400 mm | 39.063 | 69.444 | 113.636 | |||||||
| Class 150 Flanges ASME B16.5 (Stud bolt sizes) | Length of Stud Bolts | |||||||
| NPS | Outside Diameter of Flange | The diameter of Bolt Circle | The diameter of Bolt Holes | Number of Bolts | Diameter of Bolts | Raised Face 0.06 in |
Ring Joint | |
| 1/2 | 3 1/2 | 2 3/8 | 5/8 | 4 | 1/2 | 2 1/4 | – | |
| 3/4 | 3 7/8 | 2 3/4 | 5/8 | 4 | 1/2 | 2 1/2 | – | |
| 1 | 4 1/4 | 3 1/8 | 5/8 | 4 | 1/2 | 2 1/2 | 3 | |
| 1 1/4 | 4 5/8 | 3 1/2 | 5/8 | 4 | 1/2 | 2 3/4 | 3 1/4 | |
| 1 1/2 | 5 | 3 7/8 | 5/8 | 4 | 1/2 | 2 3/4 | 3 1/4 | |
| 2 | 6 | 4 3/4 | 3/4 | 4 | 5/8 | 3 1/4 | 3 3/4 | |
| 2 1/2 | 7 | 5 1/2 | 3/4 | 4 | 5/8 | 3 1/2 | 4 | |
| 3 | 7 1/2 | 6 | 3/4 | 4 | 5/8 | 3 1/2 | 4 | |
| 3 1/2 | 8 1/2 | 7 | 3/4 | 8 | 5/8 | 3 1/2 | 4 | |
| 4 | 9 | 7 1/2 | 3/4 | 8 | 5/8 | 3 1/2 | 4 | |
| 5 | 10 | 8 1/2 | 7/8 | 8 | 3/4 | 3 3/4 | 4 1/4 | |
| 6 | 11 | 9 1/2 | 7/8 | 8 | 3/4 | 4 | 4 1/2 | |
| 8 | 13 1/2 | 11 3/4 | 7/8 | 8 | 3/4 | 4 1/4 | 4 3/4 | |
| 10 | 16 | 14 3/4 | 1 | 12 | 7/8 | 4 1/2 | 5 | |
| 12 | 19 | 17 | 1 | 12 | 7/8 | 4 3/4 | 5 1/4 | |
| 14 | 21 | 18 3/4 | 1 1/8 | 12 | 1 | 5 1/4 | 5 3/4 | |
| 16 | 23 1/2 | 21 1/4 | 1 1/8 | 16 | 1 | 5 1/4 | 5 3/4 | |
| 18 | 25 | 22 3/4 | 1 1/4 | 16 | 1 1/8 | 5 3/4 | 6 1/4 | |
| 20 | 27 1/2 | 25 | 1 1/4 | 20 | 1 1/8 | 6 1/4 | 6 3/4 | |
| 24 | 32 | 29 1/2 | 1 1/4 | 20 | 1 1/4 | 6 3/4 | 7 1/4 | |
| Class 300 Flanges ASME B16.5 | Length of Stud Bolts | |||||||
| NPS | Outside Diameter of Flange | The diameter of Bolt Circle | The diameter of Bolt Holes | Number of Bolts | Diameter of Bolts | Raised Face 0.06 in |
Ring Joint | |
| 1/2 | 3 3/4 | 2 5/8 | 5/8 | 4 | 1/2 | 2 1/2 | 3 | |
| 3/4 | 4 5/8 | 3 1/4 | 3/4 | 4 | 5/8 | 3 | 3 1/2 | |
| 1 | 4 7/8 | 3 1/2 | 3/4 | 4 | 5/8 | 3 | 3 1/2 | |
| 1 1/4 | 5 1/4 | 3 7/8 | 3/4 | 4 | 5/8 | 3 1/4 | 3 3/4 | |
| 1 1/2 | 6 1/8 | 4 1/2 | 7/8 | 4 | 3/4 | 3 1/2 | 4 | |
| 2 | 6 1/2 | 5 | 3/4 | 8 | 5/8 | 3 1/2 | 4 | |
| 2 1/2 | 7 1/2 | 5 7/8 | 7/8 | 8 | 3/4 | 4 | 4 1/2 | |
| 3 | 8 1/4 | 6 5/8 | 7/8 | 8 | 3/4 | 4 1/4 | 4 3/4 | |
| 3 1/2 | 9 | 7 1/4 | 7/8 | 8 | 3/4 | 4 1/4 | 5 | |
| 4 | 10 | 7 7/8 | 7/8 | 8 | 3/4 | 4 1/2 | 5 | |
| 5 | 11 | 9 1/4 | 7/8 | 8 | 3/4 | 4 3/4 | 5 1/4 | |
| 6 | 12 1/2 | 10 5/8 | 7/8 | 12 | 3/4 | 4 3/4 | 5 1/2 | |
| 8 | 15 | 13 | 1 | 12 | 7/8 | 5 1/2 | 6 | |
| 10 | 17 1/2 | 15 1/4 | 1 1/8 | 16 | 1 | 6 1/4 | 6 3/4 | |
| 12 | 20 1/2 | 17 3/4 | 1 1/4 | 16 | 1 1/8 | 6 3/4 | 7 1/4 | |
| 14 | 23 | 20 1/4 | 1 1/4 | 20 | 1 1/8 | 7 | 7 1/2 | |
| 16 | 25 1/2 | 22 1/2 | 1 3/8 | 20 | 1 1/4 | 7 1/2 | 8 | |
| 18 | 28 | 24 3/4 | 1 3/8 | 24 | 1 1/4 | 7 3/4 | 8 1/4 | |
| 20 | 30 1/2 | 27 | 1 3/8 | 24 | 1 1/4 | 8 | 8 3/4 | |
| 24 | 36 | 32 | 1 5/8 | 24 | 1 1/2 | 9 | 10 | |
| NPS | DIA bolts (in) |
Length RF |
Length RTJ |
Number of bolts |
| 1/2 | 1/2 | 55 | 4 | |
| 3/4 | 1/2 | 65 | 4 | |
| 1 | 1/2 | 65 | 75 | 4 |
| 1¼ | 1/2 | 70 | 85 | 4 |
| 1½ | 1/2 | 70 | 85 | 4 |
| 2 | 5/8 | 85 | 95 | 4 |
| 2½ | 5/8 | 90 | 100 | 4 |
| 3 | 5/8 | 90 | 100 | 4 |
| 3½ | 5/8 | 90 | 100 | 8 |
| 4 | 5/8 | 90 | 100 | 8 |
| 5 | 3/4 | 95 | 110 | 8 |
| 6 | 3/4 | 100 | 115 | 8 |
| 8 | 3/4 | 110 | 120 | 8 |
| 10 | 7/8 | 115 | 125 | 12 |
| 12 | 7/8 | 120 | 135 | 12 |
| 14 | 1 | 135 | 145 | 12 |
| 16 | 1 | 135 | 145 | 16 |
| 18 | 1.1/8 | 145 | 160 | 16 |
| 20 | 1.1/8 | 160 | 170 | 20 |
| 24 | 1¼ | 170 | 185 | 20 |
Monel 400 Bolts are widely used in industries requiring resistance to seawater, acids, and high-pressure environments. They are selected when standard stainless steel fasteners fail under chemical or marine exposure conditions.
Monel 400 Bolts are produced using precision cold forging and CNC machining processes to ensure uniform grain structure and dimensional accuracy. Each batch undergoes controlled heat treatment to maintain alloy stability and corrosion resistance.
Quality checks include dimensional inspection, tensile testing, hardness verification, and surface finish validation. Every lot is traceable through heat number tracking and material test certificates (MTC). Compliance with ISO 9001:2015, ASTM B164, and RoHS requirements ensures global acceptance across regulated industries.
KK Fasteners integrates multi-stage inspection protocols to ensure that each fastener meets stringent performance benchmarks before dispatch to international clients.

Explore our comprehensive range of products, ensuring you find the perfect solution for your specific requirements.

Save money without compromising on quality, thanks to our competitive prices and cost-effective options.

Personalized assistance, prompt responses, and a commitment to meeting your needs, making your purchase process seamless.
Monel 400 Bolts are corrosion-resistant fasteners made from a nickel-copper alloy (UNS N04400). They are designed for severe environments such as seawater, chemical processing, and offshore oil & gas systems where high resistance to corrosion and stress cracking is required.
Monel 400 fasteners are made from a nickel-copper alloy containing approximately 63% nickel and 28–34% copper. This composition provides excellent resistance to seawater, hydrofluoric acid, and alkaline media while maintaining good mechanical strength and stability.
These bolts are generally manufactured in compliance with ASTM B164 / ASME SB164 standards. Dimensional and threading specifications may follow DIN, ISO, BS, or ANSI standards depending on application and customer requirements.
Monel 400 Bolts are widely used in marine engineering, offshore oil rigs, chemical processing plants, desalination units, and seawater handling systems. They are selected where stainless steel fails due to chloride-induced corrosion.
A reliable supplier should provide certified material test reports (MTC), compliance with ASTM standards, full traceability, and proven export experience. Engineering support and customization capability are also key indicators of quality sourcing.
Monel 400 Bolts deliver unmatched performance in seawater, chemical, and high-corrosion environments where standard fasteners degrade quickly. With strict dimensional control, certified material quality, and global supply capability, KK Fasteners supports critical industries with reliable fastening solutions engineered for long service life.
For technical specifications, pricing, or custom manufacturing requirements, contact the engineering team at KK Fasteners to request a detailed quotation and material certification sheet.