SS 316 / 316L Heavy Hex NutASTM A194 · ASME B18.2.2 · Manufacturer, trader & exporter, India
AISI 316L · UNS S31603
An SS 316 / 316L heavy hex nut is a thicker and wider hexagon nut for pressure bolting. ASTM A194 8M where specified; confirm grade and class in the purchase specification. 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.
- ASTM A194
- 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 an SS 316 / 316L Heavy Hex Nut?
- What it is
- A thicker and wider hexagon nut for pressure bolting
- Finished spec
- ASTM A194 8M where specified
- Material / feedstock
- Within the finished specification (A194 8M)
- Dimensions
- ASME B18.2.2
- Grade
- SS 316 / 316L · UNS S31603
- Best at
- Chloride-bearing process fluids, marine air and pharmaceutical service
SS 316 / 316L Heavy Hex Nut Specification
| Product | SS 316 / 316L Heavy Hex Nut |
|---|---|
| Finished fastener specification | ASTM A194 8M where specified |
| Material / feedstock specification | Within the finished specification (A194 8M) |
| Dimensional standard | ASME B18.2.2 |
| Manufacturing route | To the finished specification and purchase specification |
| 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.
SS 316 / 316L Heavy Hex Nut: Why 316L 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 SS 316 / 316L, 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 | Stainless fasteners resist atmospheric and process corrosion. SS 316 / 316L is picked for chloride-bearing process fluids, marine air and pharmaceutical service. |
|---|---|
| Typical service | Chemical & process — Piping and vessels handling mild acids and chlorides. |
| Bolting | ASTM A193 B8M studs with A194 8M nuts |
SS 316 / 316L Heavy Hex Nut Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Chromium | As specified |
| Nickel | As specified |
| Molybdenum | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Nitrogen | As specified |
| Phosphorus | As specified |
Numerical specification requirements are published only after the applicable current standard edition has been verified. Governing specification to be verified: ASTM A240 for UNS S31603.
SS 316 / 316L 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 |
| Hardness | 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 A240 for UNS S31603 — Annealed plate & sheet (316L).
Full chemistry, properties and equivalents are on the SS 316 / 316L grade page.
Other SS 316 / 316L fasteners
SS 316 / 316L 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 SS 316 / 316L heavy hex nuts?
ASTM A194 8M heavy hex nuts.
Which standard covers SS 316 / 316L heavy hex nuts?
Finished fastener specification: ASTM A194 8M where specified. Material / feedstock: Within the finished specification (A194 8M). 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 SS 316 / 316L 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