SS 310 / 310S Hex BoltUNS S31008 · ASME B18.2.1 · Manufacturer, trader & exporter, India
AISI 310S · UNS S31008
An SS 310 / 310S hex bolt is a bolt with a hexagonal head. Finished fastener specification not asserted; may be machined from ASTM A276 / A479 bar (UNS S31008), where applicable; finished fastener requirements are to the purchase specification or project drawing. Hex bolts join flanges, structures and equipment where one side is accessible for the head. Dimensions to ASME B18.2.1, or DIN 931 / 933 (legacy DIN) where an older specification calls for them.
- UNS S31008
- ASME B18.2.1
- 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 Hex Bolt?
- What it is
- A bolt with a hexagonal head
- Finished spec
- Not asserted
- Material / feedstock
- ASTM A276 / A479 bar (UNS S31008), where applicable
- Dimensions
- ASME B18.2.1 · DIN 931 / 933 (legacy DIN)
- Grade
- SS 310 / 310S · UNS S31008
- Best at
- Furnaces, burners and heat treatment at high temperature
SS 310 / 310S Hex Bolt Specification
| Product | SS 310 / 310S Hex Bolt |
|---|---|
| Finished fastener specification | Not asserted |
| Material / feedstock specification | ASTM A276 / A479 bar (UNS S31008), where applicable |
| Dimensional standard | ASME B18.2.1 · DIN 931 / 933 (legacy DIN) |
| Manufacturing route | May be machined 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 Hex Bolt
Hex bolts join flanges, structures and equipment where one side is accessible for the head. Dimensions to ASME B18.2.1, or DIN 931 / 933 (legacy DIN) where an older specification calls for them.
- Partially or fully threaded
- ASME B18.2.1 / DIN 931 / DIN 933
- Supplied with nuts and washers
More on choosing: Hex bolt guide.
SS 310 / 310S Hex Bolt: Why 310S for hex bolts
Hex bolts join flanges, structures and equipment where one side is accessible for the head. Dimensions to ASME B18.2.1, or DIN 931 / 933 (legacy DIN) where an older specification calls for them. 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 Hex Bolt Chemical Composition
Under technical review for TDS.
| Element | Current requirement |
|---|---|
| Chromium | As specified |
| Nickel | As specified |
| Carbon | As specified |
| Manganese | As specified |
| Silicon | As specified |
| Phosphorus | As specified |
| Sulphur | As specified |
| Iron | 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 S31008.
SS 310 / 310S Hex Bolt 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 S31008 — Annealed plate & sheet.
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 Hex Bolt — questions buyers ask
DIN 931 or DIN 933?
DIN 931 bolts are partly threaded; DIN 933 are fully threaded.
What nut is used with SS 310 / 310S hex bolts?
Usually a nut in the same alloy — it may be machined from ASTM A276 / A479 bar, where applicable; finished requirements are to the purchase specification or project drawing.
Which standard covers SS 310 / 310S hex bolts?
Finished fastener specification: Not asserted. Material / feedstock: ASTM A276 / A479 bar (UNS S31008), where applicable. Dimensions: ASME B18.2.1 · DIN 931 / 933 (legacy DIN). State the finished specification, material and dimensions on your purchase order or project drawing.
What decides the price of a SS 310 / 310S hex bolt?
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