SS 304 CoilASTM A240 UNS S30400 · Manufacturer, stockist & exporter, India
Also sold as AISI 304 · UNS S30400 · W.Nr 1.4301 · 18/8 stainless
SS 304 coil is supplied as full-width mother coil, slit coil or precision strip to ASTM A240. It is a austenitic chromium-nickel stainless steel, chosen for general corrosion resistance, food, water and architectural work. Kanak Steel & Engineering Co. supplies it with EN 10204 3.1 mill certificates from Mumbai to buyers across India, the Gulf, South-East Asia, South America, Europe, the UK and the USA.
- 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 304 Coil?
SS 304 coil is an austenitic chromium-nickel stainless steel supplied as coil to ASTM A240 (UNS S30400). Buyers specify it for general corrosion resistance, food, water and architectural work. It is also sold as AISI 304, UNS S30400, W.Nr 1.4301.
- What it is
- Austenitic chromium-nickel stainless steel
- Standard
- ASTM A240
- Forms
- Mother coil · slit coil · strip
- Density
- 8 g/cm³
- Finish
- 2B · BA · No.4
- Best at
- General corrosion resistance, food, water and architectural work
SS 304 Coil Specification & Sizes
| Material standard | ASTM A240 |
|---|---|
| Grade | SS 304 |
| 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 304 Coil: Slitting & Cut-to-Length Specification
304 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 304 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 |
| Nitrogen | 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 S30400.
SS 304 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 S30400 — Annealed plate & sheet.
Density & Physical Properties
| Property | Value |
|---|---|
| Density | 8 g/cm³ |
| Melting range | 1400 – 1450 °C |
| Magnetic | Non-magnetic annealed; slightly magnetic after cold work |
| PREN (approx.) | ≈ 18 |
SS 304 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 304 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 304 is most often mixed up with SS 316 / 316L — 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 304 | SS 316 / 316L |
|---|---|---|
| Nickel | As specified | As specified |
| Chromium | As specified | As specified |
| Molybdenum | — | As specified |
| Iron | As specified | As specified |
| Manganese | As specified | As specified |
SS 304 Coil Applications
SS 304 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 304 Coil vs 316L, 304L and 904L
| Grade | Coil standard | PREN (approx.) | Pick it when |
|---|---|---|---|
| SS 304L | ASTM A240 | ≈ 18 | Welded tanks, piping and vessels in general corrosive service |
| SS 304 | ASTM A240 | ≈ 18 | General corrosion resistance, food, water and architectural work |
| SS 316 / 316L | ASTM A240 | ≈ 24 | Chloride-bearing process fluids, marine air and pharmaceutical service |
| SS 904L | ASTM A240 | ≈ 35 | Dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water |
PREN = Cr + 3.3 Mo + 16 N, from mid-range chemistry. A screening guide, not a substitute for corrosion data on your medium.
SS 304 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 304 fits.
About 18% chromium forms the passive film that makes the steel stainless.
Nickel keeps the structure austenitic — tough at low temperature and easy to form and weld.
Standard carbon level: fine for most work, but choose 304L where heavy sections are welded and service is corrosive.
Without molybdenum, 304 pits in chlorides — step up to 316L for coastal or salty service.
How your 304 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 before processing is available on request.
- 03Processing — cutting, machining or bevelling to your specification, with heat numbers marked.
- 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 304 Coil
SS 304 welds by all common arc processes. A few points our buyers ask about:
| Matching filler | ER308 / ER308L (AWS A5.9) |
|---|---|
| Over-alloyed filler | ER309L for dissimilar joints to carbon steel |
| 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 304 fittings and 304 flanges for the matching pipe-system parts.
How to Order SS 304 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 304 coil for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiSS 304 coil — questions buyers ask
Is SS 304 the same as AISI 304?
AISI 304, UNS S30400, W.Nr 1.4301 are names used for SS 304 (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 304 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 304 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 304 cut-to-length sheets from coil?
Yes. Coil can be levelled and cut to length; state length tolerance and flatness.
SS 304 or SS 904L — which should I choose?
SS 304 is chosen for general corrosion resistance, food, water and architectural work. SS 904L 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