Stainless Steel, Duplex & Nickel Alloy Coils
Coil is flat product wound for continuous processing — slitting, stamping, tube-making and roll-forming. Choose the material, then specify thickness, width, coil ID and weight to suit your line. We supply mother coil, slit coil and strip with EN 10204 3.1 certificates.
- ASTM A480
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is coil, and how is it specified?
Coil is sheet or strip wound into a roll and supplied either at mill width or slit to narrower widths for stamping, roll-forming and tube mills. Stainless and duplex coil is ordered to ASTM A240 with A480 finishes and tolerances; buyers specify thickness, width, inner diameter and coil weight as well as grade.
How to order coils: checklist
- Grade and specification — e.g. ASTM A240 304L
- Thickness and width (mill width or slit width with tolerance)
- Finish — 2B, BA, No.1
- Coil inner diameter and maximum coil weight
- Edge — mill or slit
- Certificate — EN 10204 3.1
Coil by Material Family and Grade
Each coil page sits under its grade. Open the grade’s coil page for its standard, finishes and slitting options.
Coil Specification: What to Put on the Order
Coil has to fit the decoiler and run without breaks, so dimensions and edge condition matter as much as the grade. These are the lines every coil enquiry should carry.
| Thickness | Nominal and tolerance — half tolerance on request for stamping |
|---|---|
| Width | Mill width, or slit width with tolerance |
| Inner diameter | 508 mm or 610 mm are common — match your decoiler |
| Coil weight | Maximum your crane and decoiler handle |
| Edge | Mill edge or slit edge; burr limit |
| Camber | Limit for slit strip that feeds tube mills and dies |
| Finish & interleaving | Finish code; paper or PVC between laps for bright finishes |
Coil, Strip or Sheet?
Under ASTM A480 and B906, cold-rolled material under 3/16" (4.76 mm) and narrower than 24" is strip; 24" and wider is sheet, whether supplied flat or in coil. Order coil when you will process the material on your own line; order sheet when you need flat pieces.
How Coil Standards Fit Together
Which Coil Grade for Which Use?
A starting point; confirm with your process and forming requirements.
| Service | Start with |
|---|---|
| Kitchen, architecture, general stamping | SS 304 / 304L |
| Food, pharma, coastal | SS 316L |
| Acid-plant and heat-exchanger parts | SS 904L |
| Strength in chloride service | Duplex 2205 |
| Bellows and flexible hose | Inconel 625 / 825 |
| Heat-treatment parts | Inconel 600 |
Coils Grades & Material Standards
| Grade | Material standard | Best for |
|---|---|---|
| Inconel 825 | ASTM B424 | Sulphuric and phosphoric acid service, chloride stress-corrosion cracking and sour gas |
| SS 904L | ASTM A240 | Dilute sulphuric acid, phosphoric acid and chloride-bearing cooling water |
| SS 304 | ASTM A240 | General corrosion resistance, food, water and architectural work |
| SS 304L | ASTM A240 | Welded tanks, piping and vessels in general corrosive service |
| SS 310 / 310S | ASTM A240 | Furnaces, burners and heat treatment at high temperature |
| SS 316 / 316L | ASTM A240 | Chloride-bearing process fluids, marine air and pharmaceutical service |
| SS 321 | ASTM A240 | High-temperature service between 425 and 815 °C |
| SS 347 | ASTM A240 | Welded high-temperature piping in refineries and power plants |
| Duplex 2205 | ASTM A240 | Strength with chloride resistance at a stainless-steel budget |
| Super Duplex 2507 | ASTM A240 | Seawater and high-chloride service where strength also matters |
| Inconel 600 | ASTM B168 | High-temperature oxidation, caustic and nuclear service |
| Inconel 625 | ASTM B443 | Seawater, high strength and high temperature in one alloy |
| Inconel 718 | ASTM B670 | Very high strength at temperatures up to about 650 °C |
| Incoloy 800 / 800H / 800HT | ASTM B409 | Furnaces, petrochemical heaters and high-temperature piping |
| Hastelloy C276 | ASTM B575 | The most aggressive mixed acids, wet chlorine and hypochlorite |
| Hastelloy C22 | ASTM B575 | Mixed oxidising and reducing acids, and weld overlays |
| Monel 400 | ASTM B127 | Seawater, hydrofluoric acid and marine service |
| S275JR | EN 10025-2 | General structures, frames and fabrication |
| S355J2+N | EN 10025-2 | Heavy structures, cranes and offshore frames |
| IS 2062 E250 / E350 | IS 2062 | Structures, fabrication and general engineering in India |
Guides, tools & standards for coils
Coils for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiCoils — questions buyers ask
What coil inner diameters are available?
508 mm (20") and 610 mm (24") are the common IDs; tell us what your decoiler takes.
Can coil be slit to narrow widths?
Yes — slit coil and strip to your width and tolerance, with coil weight to suit your line.
What is the difference between coil and strip?
Strip is narrower than 24" (610 mm, 600 mm in metric A480M); coil is the wound form of either sheet or strip.
Which finish do coils come in?
Stainless: 2B, BA, 2D or No.4. Nickel alloys: cold rolled, annealed and descaled, with bright annealed on request.