Monel 400 Heavy Hex NutUNS N04400 · ASME B18.2.2 · Manufacturer, trader & exporter, India
Alloy 400 · UNS N04400
A Monel 400 heavy hex nut is a thicker and wider hexagon nut for pressure bolting. ASTM F467 (N04400) where specified, 0.250–1.500 in.; otherwise may be machined from ASTM B164 bar (UNS N04400), where applicable — finished requirements to the purchase specification or project drawing. Heavy hex nuts go with stud bolts on flanges. They spread load better and resist thread stripping at high preload. Made to ASME B18.2.2.
- UNS N04400
- ASME B18.2.2
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is a Monel 400 Heavy Hex Nut?
- What it is
- A thicker and wider hexagon nut for pressure bolting
- Finished spec
- ASTM F467 (N04400) where specified, 0.250–1.500 in.
- Material / feedstock
- ASTM B164 bar (UNS N04400), where applicable
- Dimensions
- ASME B18.2.2
- Grade
- Monel 400 · UNS N04400
- Best at
- Seawater, hydrofluoric acid and marine service
Monel 400 Heavy Hex Nut Specification
| Product | Monel 400 Heavy Hex Nut |
|---|---|
| Finished fastener specification | ASTM F467 (N04400) where specified, 0.250–1.500 in. |
| Material / feedstock specification | ASTM B164 bar (UNS N04400), where applicable |
| Dimensional standard | ASME B18.2.2 |
| Manufacturing route | To the finished specification where specified; otherwise machining from bar, where applicable |
| Project / purchase specification | Yes — finished fastener requirements are to the purchase specification or project drawing |
| Sizes | M10 – M64 · ½" – 4" (others on request) |
| Threads | UNC · UN-8 · metric coarse |
| Testing | PMI (as specified in the PO) · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 or 3.2 on request / as specified in the PO |
When to Choose a Heavy Hex Nut
Heavy hex nuts go with stud bolts on flanges. They spread load better and resist thread stripping at high preload. Made to ASME B18.2.2.
- Thicker than standard hex nuts
- ASME B18.2.2
- Paired with A193 studs
More on choosing: Heavy hex nut guide.
Monel 400 Heavy Hex Nut: Why 400 for heavy hex nuts
Heavy hex nuts go with stud bolts on flanges. They spread load better and resist thread stripping at high preload. Made to ASME B18.2.2. In Monel 400, the choice usually comes down to the medium and temperature — the rows here are the points buyers check for this exact combination.
| Why this grade | Nickel-alloy fasteners match nickel-alloy flanges in corrosive or hot service. Monel 400 is picked for seawater, hydrofluoric acid and marine service. |
|---|---|
| Typical service | Marine — Pump shafts, valves and seawater piping. |
| Bolting | B7 (coated), B8M or nickel-alloy studs in Monel 400 (bar to ASTM B164, where applicable), as the project specifies |
| Sour service | Listed in NACE MR0175 / ISO 15156-3 within its limits — state it on the order |
Monel 400 Heavy Hex Nut Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Nickel (+Co) | As specified |
| Copper | As specified |
| Iron | As specified |
| Manganese | As specified |
| Carbon | As specified |
| Silicon | As specified |
| Sulphur | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM B127 for UNS N04400.
Monel 400 Heavy Hex Nut Mechanical Properties
Under technical review for TDS.
| Property | Current requirement |
|---|---|
| Tensile strength | As specified |
| Yield strength 0.2% | As specified |
| Elongation | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification and condition to be verified: ASTM B127 for UNS N04400 — Annealed plate.
Full chemistry, properties and equivalents are on the Monel 400 grade page.
Standards on this page
Other Monel 400 fasteners
Monel 400 Heavy Hex Nut — questions buyers ask
Why use heavy hex nuts on flanges?
They provide more thread engagement and bearing area for the high preload flange joints need.
What nut is used with Monel 400 heavy hex nuts?
Usually a nut in the same alloy — it may be machined from ASTM B164 bar, where applicable; finished requirements are to the purchase specification or project drawing.
Which standard covers Monel 400 heavy hex nuts?
Finished fastener specification: ASTM F467 (N04400) where specified, 0.250–1.500 in.. Material / feedstock: ASTM B164 bar (UNS N04400), where applicable. Dimensions: ASME B18.2.2. State the finished specification, material and dimensions on your purchase order or project drawing.
What decides the price of a Monel 400 heavy hex nut?
The alloy price, the size and dimensions, quantity, and the testing and documents required. Send your list and we quote the same working day.
What documents do you supply?
EN 10204 3.1 or 3.2 certificates available on request / as specified in the PO; dimensional reports as required. PMI can be arranged depending on product and requirements, as specified in the PO.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026