How stainless steel cookware is made
Pots, pans, saucepans, stockpots, kadais and pressure-pan bodies start as steel circles cut from coil. The circle is deep-drawn on a press in one or more stages, trimmed, and the rim is rolled or left straight. Stainless steel spreads heat poorly, so the base is where most of the engineering goes. There are two common builds:
- Impact-bonded or encapsulated base. An aluminium disc is placed under the pot and capped with a stainless plate, then the three are bonded under heavy impact and heat. A ferritic 430 cap makes the pan work on induction. The joint around the capsule is the weak point.
- Clad (tri-ply or multi-ply). Layers of stainless and aluminium, sometimes copper, are roll-bonded into sheet before drawing, so the core runs up the walls. There is no capsule seam, but delamination at the rim or a blistered layer is possible.
Handles are riveted, spot-welded or screwed on; lids are steel or tempered glass with a steel rim. The pieces are then polished to a mirror or satin finish and cleaned. India's largest kitchenware export line is household articles of stainless steel (HS 7323 93), US$415.82 million in FY2025-26 (TradeStat, provisional), which covers cookware and tableware together. Current official cluster lists name no stainless utensil export cluster (an older MSME-DI profile of Yamunanagar district, with data to 2010-11, recorded a small stainless and aluminium utensil group at Jagadhri with no exports; see Jagadhri–Yamunanagar), so we name no export town.
Grade matters most. 304 steel, often sold as 18/8 or 18/10, is the usual buyer specification. 200-series steels such as 201 use less nickel and more manganese, cost less, and look identical when polished. They are the most common substitution risk.
What we check on stainless steel cookware
| Check | How it is checked | What fails |
|---|---|---|
| Grade and marking | Stamp on the base read against the PO; magnet on body and base; samples pulled and sealed for lab grade analysis | Wrong or missing stamp; body pulls a magnet strongly where 304 was ordered; lab result not 304 |
| Base bond | Seam around an encapsulated base examined all round; base tapped for a dull or hollow sound; heat test on a hob if your protocol includes it | Gap, crack or step at the capsule seam; hollow sound; base moves after heating |
| Base flatness | Pan set on a flat glass plate and a straightedge laid across the base, cold | Rocks on the plate, or a bulge (convex base) where a flat or slightly concave base was specified |
| Induction response | Magnet pull across the base plate; test on an induction hob where available | Weak or patchy pull; hob does not detect the pan |
| Handles and rivets | Hand pull and twist on every sampled handle; rivet heads checked inside and out | Any play, cracked rivet head, spot weld that gives, sharp rivet edge inside |
| Wall thickness and weight | Micrometer at the rim; piece weight against the approved sample | Thinner than specification; light weight across the lot |
| Cooking surface | White cloth wiped inside; surface checked under light for pits and scratches | Black or grey polishing compound on the cloth, pits, deep polishing lines |
| Capacity and markings | Filled to the brim or the marked line and measured; volume scale compared with the measured volume | Capacity short; wrong or misprinted volume marks |
| Lid fit | Lid rotated on the pot; glass lid rim and steam vent checked | Rocking lid, chipped glass, loose knob |
Common stainless steel cookware defects and how they are classed
| Defect | Typical cause | Class |
|---|---|---|
| Handle loose or rivet cracked | Undersized rivets, poor peening, weak spot weld | Critical: a handle that gives with hot contents can cause burns |
| Steel grade not as ordered | 200-series or unmarked steel used to save cost | Critical for the order: material not as contracted |
| Base capsule separating | Poor impact bonding, dirty aluminium disc | Major |
| Base rocking or convex | Base distorted in bonding or cooling | Major |
| Polishing compound left inside | Incomplete cleaning after buffing | Major (food-contact surface) |
| Rust spots or tea staining | Iron particles from grinding tools, poor cleaning | Major |
| Heat tint on the base | Bonding heat not removed by polishing | Minor if within the sample |
| Dents and scratches | Handling between stages, nested without separators | Minor or major by size and position |
Your defect list decides the final class.
Market rules for stainless steel cookware
- EU. Regulation (EC) 1935/2004 applies, but there is no EU-specific measure for metals. Buyers and labs use the Council of Europe Resolution CM/Res(2013)9 and its technical guide, which set specific release limits for metals including chromium and nickel. Germany's LFGB is often named in purchase orders; there is no LFGB certificate. See EU 1935/2004 and LFGB.
- Performance. EN 12983-1:2023 sets safety and performance requirements for domestic cookware used on a hob, including handle pull-off and suitability for different heat sources. It is a voluntary standard, but many EU buyers specify it, and the induction claim on the box should be backed by it or a similar test.
- US. FDA has no approval scheme for finished cookware; every food contact component must be authorized for its use. Plastic or silicone parts on handles and lids need their own status. See FDA food contact.
- California. Brass knobs, coated exteriors or decorative parts can bring lead into scope of Prop 65.
- Labels. Induction symbol, dishwasher and oven claims, care instructions and the EU business address must match what was tested.
Grade analysis and metal release tests are done through lab testing coordination.
Packing, transit and your purchase order
Polished stainless shows every scratch. Nested sets need paper or foam between pieces, and protective film on mirror surfaces should come off cleanly without leaving adhesive. Lids packed loose rattle against rims in transit and chip glass. The inspector checks inner packing, the drop strength of the carton and that set boxes hold the right pieces.
Put these in your purchase order:
- Steel grade for each part: body, base plate, rivets, handles, lid.
- Base build (encapsulated or clad), core metal and layer count.
- Wall thickness, base diameter and piece weight with tolerance.
- Base flatness requirement (flat or concave limit) and induction compatibility.
- Finish inside and out, and a clean-cloth test for residue.
- Handle fixing method and rivet count; capacity and volume marks.
- Markings on the base and the test reports you hold for this grade.
For thalis, bowls, tumblers and other serveware, see stainless steel tableware and serveware. For coated pans, see aluminium and non-stick cookware.
Sources
- Regulation (EC) No 1935/2004 on food contact materials (EUR-Lex)
- EDQM FAQ: metals and alloys in food contact materials (CM/Res(2013)9)
- BSI: EN 12983-1, Cookware for use on top of a stove, cooker or hob, general requirements
- FDA: Determining the regulatory status of components of a food contact material
- Department of Commerce, TradeStat: commodity-wise exports (HS 732393, FY2025-26 provisional)