We are Riddhi Siddhi Impex, a Mumbai-based supplier and stockist of Incoloy 840 Coils, established in 2002. We stock titanium/aluminium-bearing 20Cr-20Ni Alloy 840 coils (0.03-5 mm thick) with ±0.1 mm width tolerance from primary mills. Our ISO 9001/14001/45001-certified company has the capacity to supply 400-500 tonnes monthly, providing EN 10204 3.1/3.2 mill test certificates on request.
Incoloy 840 Coils are flat-rolled lengths of an austenitic heat-resisting stainless steel carrying roughly 20% chromium and 20% nickel, with small titanium and aluminum additions and iron as the balance. Those additions bind the oxide into a tight, adherent scale, so the coil surface resists scaling in air to about 1038°C. Trade practice keeps the Incoloy name, though the chemistry sits nearer heat-resisting stainless than the 800 series. Incoloy 840 Coils are typically used to manufacture electric heating elements for domestic appliances like water heaters and electric ovens.
As a reliable Incoloy 840 coil supplier, we process this specialised inconel coil on our own in-house slitting lines rather than pulling pre-slit sizes from a reseller's shelf. Material ships in annealed condition, slit to any width from 3 mm to 2000 mm, with a mill test certificate on request included in each consignment.
We supply Incoloy 840 coils in annealed condition, slit to width from ready stock, across the finishes and edges below.
| Parameter | Details |
|---|---|
| Standard | ASTM A240 / ASME SA-240 |
| Thickness | 0.03 mm to 5 mm |
| Width | 3 mm to 2000 mm |
| Width Tolerance | ±0.1 mm |
| Coil ID | 150 mm to 610 mm |
| Coil OD | Up to 1800 mm |
| Condition | Annealed (standard mill) |
| Surface Finish | BA (Bright Annealed), 2B, Matte, Matte PVC, Skin Pass |
| Edge | Slit edge, Mill edge, Deburred edge, Round edge |
Matched 18.0 to 22.0% bands of chromium and nickel define UNS S33400 coils, while titanium and aluminium anchor the protective scale. Values follow the alloy producer specification.
| Element | Composition (%) |
|---|---|
| Chromium (Cr) | 18.0 to 22.0 |
| Nickel (Ni) | 18.0 to 22.0 |
| Iron (Fe) | Balance |
| Manganese (Mn) | 1.00 max |
| Silicon (Si) | 1.00 max |
| Titanium (Ti) | 0.60 max |
| Aluminium (Al) | 0.60 max |
| Copper (Cu) | 0.75 max |
| Carbon (C) | 0.08 max |
| Phosphorus (P) | 0.03 max |
| Sulphur (S) | 0.015 max |
Annealed Alloy 840 coil pairs 572 MPa tensile strength with 40% elongation, so it uncoils, forms, and welds without cracking. Figures are nominal room-temperature values, indicative at the thinnest gauges.
| Property | Value |
|---|---|
|
Tensile Strength
|
572 MPa (83 ksi) |
|
Yield Strength (0.2% offset)
|
241 MPa (35 ksi) |
|
Elongation in 50 mm
|
40% |
|
Hardness
|
70 HRB |
Buyers ordering by a regional designation can cross-check our 840 coil stock below.
| Country / Standard | Designation |
|---|---|
| USA (UNS) | S33400 |
| Germany (W.Nr) | 1.4847 |
These 4 industries specify most of the Incoloy 840 coils we dispatch. The alloy is selected by most of the industries through scaling resistance at red heat and an annealed condition suited to continuous forming lines.
Heating-element producers run Alloy 840 coil through tube mills as sheathing stock for tubular and cartridge heaters. Coil feed supports continuous production with minimal interruptions, and the alloy builds a stable oxide in service that helps maintain dimensional stability during service.
Exhaust-hardware fabricators press Incoloy 840 coils into heat shields and flexible connectors exposed to hot, oxidising gas. The 20Cr-20Ni matrix resists prolonged exposure to hot exhaust gases, and slit coil feeds progressive tooling directly.
Furnace builders take Nickel Alloy 840 coil for muffle liners, radiant sections, and expansion bellows running under continuous heat. Oxidation, sulphidation, and carburisation attack affordable liners first, so the grade stretches rebuild intervals.
Process plants roll UNS S33400 coil into heater internals, baffles, and thermal processing parts. Oxidation resistance holds to around 1038 °C, which matches the duty inside fired heaters.
Coil orders leave from our Mumbai and Taloja warehouses in wooden cases or on pallets.
| Parameter | Details |
|---|---|
| Packaging | Wooden cases, pallet packing |
| Incoterms | FOB, CIF, CFR, EXW Mumbai |
| Dispatch Points | Mumbai and Taloja warehouses |
| Standard Lead Time | 4 to 5 days |
| Urgent Dispatch | 2 to 3 days |
| Payment Terms | Advance, credit, LC |
| Certification | EN 10204 Type 3.1 / 3.2 on request |
Incoloy 840 strips and coils are niche products, and publicly visible pricing benchmarks are limited. Contact us for prices.
Incoloy 840 coils carry the UNS designation S33400 and the Werkstoff Number 1.4847.
We supply Incoloy 840 coils from 0.03 mm to 5 mm thick, slit to any width from 3 mm to 2000 mm at ±0.1 mm. Coil ID runs 150 mm to 610 mm, with OD up to 1800 mm.
Yes, Incoloy 840 coils are suitable for heating elements; sheathing for tubular and cartridge heaters is the grade's best-known duty. The alloy forms and welds readily, then holds a protective oxide at operating temperature.
The main difference between Incoloy 840 and Incoloy 800 coils is the base chemistry. Alloy 840 is a titanium and aluminium-bearing 20Cr-20Ni heat-resisting stainless chosen for scaling resistance, while Incoloy 800 carries more nickel for creep duty.
The finishes available for Incoloy 840 coils are BA (Bright Annealed), 2B, Matte, Matte PVC, and Skin Pass. Edge options cover slit, mill, deburred, and round.
The typical lead time for Incoloy 840 coils is 4 to 5 days from our Mumbai warehouse, with urgent dispatch in 2 to 3 days. Ready stock keeps most orders on the shorter side.
You can source Incoloy 840 coils in India from us at Riddhi Siddhi Impex. Our Mumbai warehouse holds Alloy 840 coil stock for prompt dispatch, and as a supplier, stockist, and exporter, we serve buyers across India and overseas. WhatsApp us for getting a quote within 24 hours.
