SS 310 / 310S Heavy Hex NutASTM A276 · ASME B18.2.2 · Manufacturer, stockist & exporter, India
AISI 310S · UNS S31008
An SS 310 / 310S heavy hex nut is a thicker and wider hexagon nut for pressure bolting, made from SS 310 / 310S to ASTM A276 / A479. 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 A276
- 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 310 / 310S Heavy Hex Nut?
- What it is
- A thicker and wider hexagon nut for pressure bolting
- Material
- ASTM A276 / A479
- Dimensions
- ASME B18.2.2
- Grade
- SS 310 / 310S · UNS S31008
- Best at
- Furnaces, burners and heat treatment at high temperature
SS 310 / 310S Heavy Hex Nut Specification
| Product | SS 310 / 310S Heavy Hex Nut |
|---|---|
| Material standard | ASTM A276 / A479 |
| Dimensional standard | ASME B18.2.2 |
| Sizes | M10 – M64 · ½" – 4" (others on request) |
| Threads | UNC · UN-8 · metric coarse |
| Testing | PMI · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
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 310 / 310S Heavy Hex Nut: Why 310S 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 310 / 310S, 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 310 / 310S is picked for furnaces, burners and heat treatment at high temperature. |
|---|---|
| Typical service | Furnace parts — Muffles, retorts, radiant tubes and conveyor belts. |
| Bolting | A193 B8 or project-specified bolting |
SS 310 / 310S Heavy Hex Nut Chemical Composition
| Element | Weight % |
|---|---|
| Chromium | 24.0 – 26.0 |
| Nickel | 19.0 – 22.0 |
| Carbon | 0.08 max |
| Manganese | 2.00 max |
| Silicon | 1.50 max |
| Phosphorus | 0.045 max |
| Sulphur | 0.030 max |
| Iron | Balance |
SS 310 / 310S Heavy Hex Nut Mechanical Properties
| Annealed plate & sheet | Value |
|---|---|
| Tensile strength | 515 MPa · 75 ksi |
| Yield strength 0.2% | 205 MPa · 30 ksi |
| Elongation | 40% |
| Hardness | 217 HB max |
Full chemistry, properties and equivalents are on the SS 310 / 310S grade page.
Standards on this page
Other SS 310 / 310S fasteners
SS 310 / 310S Heavy Hex Nuts for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiSS 310 / 310S 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 310 / 310S heavy hex nuts?
A nut in the same alloy, machined from ASTM A276 / A479 bar, unless the project specifies otherwise.
Which standard covers SS 310 / 310S heavy hex nuts?
The material is ASTM A276 / A479; dimensions follow ASME B18.2.2. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a SS 310 / 310S 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 mill certificates as standard, 3.2 with third-party inspection on request, plus dimensional and PMI reports.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026