SS 310 / 310S CoilASTM A240 UNS S31008 · Manufacturer, trader & exporter, India
Also sold as AISI 310S · UNS S31008 · W.Nr 1.4845 · Heat-resisting stainless
SS 310 / 310S coil is supplied as full-width mother coil, slit coil or precision strip to ASTM A240. It is a heat-resisting austenitic stainless steel with 25% chromium and 20% nickel, chosen for furnaces, burners and heat treatment at high temperature. Kanak Steel & Engineering Co. manufactures, trades and exports it from Mumbai; EN 10204 3.1 or 3.2 certificates are available on request / as specified in the PO. Markets we have supplied to include Oman, UAE, Saudi Arabia, Brazil, Argentina, Spain and Chile (India is the home market).
- Stock & mill supply
- EN 10204 3.1 / 3.2
- PMI on request
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is SS 310 / 310S Coil?
SS 310 / 310S coil is a heat-resisting austenitic stainless steel with 25% chromium and 20% nickel supplied as coil to ASTM A240 (UNS S31008). Buyers specify it for furnaces, burners and heat treatment at high temperature. It is also sold as AISI 310S, UNS S31008, W.Nr 1.4845.
- What it is
- Heat-resisting austenitic stainless steel with 25% chromium and 20% nickel
- Standard
- ASTM A240
- Forms
- Mother coil · slit coil · strip
- Density
- 7.9 g/cm³
- Finish
- 2B · BA · No.4
- Best at
- Furnaces, burners and heat treatment at high temperature
SS 310 / 310S Coil Specification & Sizes
| Material standard | ASTM A240 |
|---|---|
| Grade | SS 310 / 310S |
| Thickness | 0.1 mm to 6 mm, depending on mill route |
| Width | Mill width, or slit from 10 mm upwards |
| Coil weight & ID | To order — state maximum coil weight and inner diameter |
| Finish | 2B · BA · No.4 · 2D |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
SS 310 / 310S Coil: Slitting & Cut-to-Length Specification
310S coil is bought for a production line, so state thickness, slit width, inner diameter and maximum coil weight with the grade.
| Standard | ASTM A240 |
|---|---|
| Thickness tolerance | Per ASTM A480 |
| Finish | 2B · BA · No.4 · 2D |
ID, coil weight, edge, camber and interleaving: see the coil guide.
SS 310 / 310S Coil 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 Coil 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.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 7.9 g/cm³ |
| Melting range | 1400 – 1450 °C |
| Magnetic | Non-magnetic annealed |
| PREN (approx.) | ≈ 25 |
SS 310 / 310S Equivalent Grades
Six-digit Harmonized System heading (iron and steel, chapter 72–73). Your country adds its own digits — confirm with your customs broker. All HS codes.
How to Verify SS 310 / 310S Coil with PMI
Positive material identification with a handheld XRF gun confirms the alloy on the piece itself, in seconds, before it is cut or welded. SS 310 / 310S is most often mixed up with SS 304 — the table shows which elements tell them apart.
Handheld XRF does not measure carbon or nitrogen; those come from the mill certificate or optical emission (OES) testing. PMI can be arranged on request — state it on your enquiry.
Under technical review for TDS.
| Element | SS 310 / 310S | SS 304 |
|---|---|---|
| Nickel | As specified | As specified |
| Chromium | As specified | As specified |
| Iron | As specified | As specified |
| Manganese | As specified | As specified |
SS 310 / 310S Coil Applications
SS 310 / 310S is specified when the cheaper grade will not survive the service but a higher alloy would be more than the job needs. These are the jobs our buyers use it for.
SS 310 / 310S Coil vs 304, 321 and 800
| Grade | Coil standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| Incoloy 800 / 800H / 800HT | ASTM B409 | — | Furnaces, petrochemical heaters and high-temperature piping |
| SS 304 | ASTM A240 | ≈ 18 | General corrosion resistance, food, water and architectural work |
| SS 321 | ASTM A240 | ≈ 18 | High-temperature service between 425 and 815 °C |
| SS 310 / 310S | ASTM A240 | ≈ 25 | Furnaces, burners and heat treatment at high temperature |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
SS 310 / 310S Corrosion Resistance — Element by Element
Each alloying addition has a job. Knowing which one protects against your medium is the quickest way to judge whether 310S fits.
25% chromium builds a tight scale that resists oxidation in continuous service up to about 1100 °C.
20% nickel keeps the alloy austenitic and strong at furnace temperatures.
Silicon improves resistance to scaling and carburising atmospheres.
Without molybdenum, 310S is not a chloride grade — use it for heat, not for seawater.
How your 310S coil order runs
- 01Enquiry review — we confirm size, standard edition and documents against your MR or drawing.
- 02Heat selection & PMI — the mill certificate is checked against your order; PMI can be arranged depending on product and requirements, as specified in the PO.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked as specified in the PO.
- 04Inspection — your third-party inspector witnesses, or we share photos and test reports.
- 05Packing & dispatch — seaworthy packing from Nhava Sheva (JNPT), Mumbai, FOB or CIF, documents sent before the vessel sails.
Welding & Fabricating SS 310 / 310S Coil
SS 310 / 310S welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ER310 (AWS A5.9) |
|---|---|
| Over-alloyed filler | ERNiCr-3 for joints to nickel alloys |
| Preheat | Not required; keep interpass temperature low |
| Cutting | Thermal or abrasive cutting; grind off heat-tinted edges before welding |
Follow your approved WPS; this is general guidance. See also 310S fittings and 310S flanges for the matching pipe-system parts.
How to Order SS 310 / 310S Coil: RFQ Checklist
Get an accurate quote the first time. Copy this list into your enquiry:
- Thickness and width
- Coil weight and inner diameter
- Finish and edge (mill or slit)
- Certificate type
- Delivery port and date
SS 310 / 310S coil — questions buyers ask
Is SS 310 / 310S the same as AISI 310S?
AISI 310S, UNS S31008, W.Nr 1.4845 are names used for SS 310 / 310S (W.Nr / EN numbers and older UNS variants are the closest designations; their limits can differ slightly, so specify the UNS number and ASTM grade on the order), and coil is ordered to ASTM A240 whichever name is on the enquiry.
Can SS 310 / 310S coil be slit to width?
Yes. Coils can be slit to narrow widths for stamping, tube making and spring work; state width tolerance and coil weight on the enquiry.
What inner diameter do SS 310 / 310S coils have?
508 mm (20") and 610 mm (24") are the common IDs. Tell us your decoiler ID and maximum coil weight and we slit to suit.
Can I order SS 310 / 310S cut-to-length sheets from coil?
Yes. Coil can be levelled and cut to length; state length tolerance and flatness.
SS 310 / 310S or Incoloy 800 / 800H / 800HT — which should I choose?
SS 310 / 310S is chosen for furnaces, burners and heat treatment at high temperature. Incoloy 800 / 800H / 800HT is the step up when you need more pitting resistance or strength. See the comparison table on this page, or ask us with your process conditions.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026