Verification is not a single test — it is a three-stage process: documents before deposit, checks during production, and inspection before loading. Skipping any one of them leaves the entire purchase order exposed, because 201 and 304 stainless steel are visually identical and the substitution usually happens at the raw-material stage, not in the workshop. This guide walks through each stage the way a professional manufacturer in China expects it to run.
A Stainless steel rice pot looks convincing on a supplier's product page no matter what alloy is inside it. What protects your money is paper, instruments, and sampling discipline. At Tailong, roughly half of our OEM clients run their own verification on top of ours — and we encourage it, because a buyer who knows how to verify is a buyer who stays out of disputes.
1. What Documents and Tests Should You Demand Before Production Starts?
Lock the grade on paper before any money moves. The contract stage is where verification is cheapest, and where most buyers give away their leverage by accepting vague terms like "food-grade stainless steel" — a phrase that legally covers 201 as well as 304.
| Document / Test | What to Check | Red Flag |
| Mill Test Certificate (MTC 3.1) | Cr ≥ 18.0%, Ni ≥ 8.0%; heat number traceable | "Certificate available" without a heat number |
| Steel coil purchase invoice | Matches the MTC heat number | Invoices from trading intermediaries only |
| Migration test report | Per market: FDA 21 CFR (US), LFGB (DE/EU), EU 1935/2004 | Report issued to a different product or factory |
| Golden sample | Signed and sealed by both sides, kept off the production line | "Sample = photo" instead of a physical seal |
Three practical notes on these documents. First, an MTC 3.1 is issued by the steel mill itself and traces a specific coil of material — a mill certificate is worth ten letters of self-declaration. Second, migration testing is done on finished product in accredited labs, and reports must name the exact factory and model; recycled PDFs from other companies are common in the industry. Third, the golden sample is your referee: when a pre-shipment dispute arises, the sealed sample is what arbitration compares against, whether the item is a pot, a kettle, or a Stainless steel snow flat pan ordered in the same container.
✅ Bottom line: Fix the grade in the contract with an MTC 3.1, market-correct migration reports, and a sealed golden sample before paying the deposit.
2. How Should On-Site and Pre-Shipment Checks Actually Run?
Test random units from the real production batch, not showroom pieces. Document checks confirm intent; physical checks confirm delivery. This stage is where a factory proves that what it promised on paper is what came off the line.
- XRF scan — the strongest single tool. A handheld X-ray fluorescence analyzer reads the exact alloy composition of any polished spot in seconds: Ni below 6% means 201. Ask for scans on 3–5 random units pulled from the middle of the batch, including the cooking surface and the base.
- Drop-test screening — a molybdenum/nickel reagent changes color by nickel content. Slower than XRF but cheap enough for your own QC staff to run on every carton sample.
- Third-party inspection — engage SGS, Bureau Veritas, or TÜV for an AQL sampling inspection 7–10 days before shipment. For an added fee they will combine the standard defect check with an alloy verification report.
- Contract penalty clause — state the remedy if the alloy fails: full refund of the affected quantity plus re-inspection costs. A clause like this changes factory behavior before production even starts.
This routine works identically across cookware categories. Whether the order is a 24 cm pot, a deep stock vessel, or a Stainless steel wok, the alloy check is the same XRF scan on the same kind of surface — so build one standard verification SOP and reuse it on every SKU you source. Yongkang Tailong Kitchenware Co., Ltd. supports customer-arranged third-party inspection and XRF testing on all export orders, and provides mill certificates as standard documentation with every wholesale shipment.
✅ Bottom line: XRF scan random units from the actual batch, add third-party AQL inspection before loading, and back it with a penalty clause in the contract.
FAQ
Q: Is a supplier's mill certificate alone enough proof of 304? A: No. Certificates occasionally get recycled between orders, and an MTC proves the raw coil, not your finished units. Treat the certificate as the entry ticket, then confirm with XRF on the production batch and — for large orders — third-party inspection.
Q: How much does third-party alloy verification cost, and is it worth it? A: Standard AQL inspection in China typically runs a few hundred US dollars per man-day, and adding an XRF check is marginal on top. Against a container of cookware worth $20,000–50,000, it is the cheapest insurance in the procurement budget — and it strengthens any claim under your penalty clause.
Q: Can Tailong produce samples in both 304 and 201 for comparison? A: Yes. Tailong offers OEM/ODM custom sampling so buyers can XRF-test both grades side by side before committing, and factory-direct quotations always state the food-contact grade explicitly. Bulk production follows the grade written in the PI, backed by mill certificates.
Ship Your Next Order with Documents Attached
Request a free 304 verification pack from Tailong — mill certificate template, migration test report, and golden-sample procedure — together with a factory-direct quotation for your target market. Send your specification and quantity, and our team will return FOB pricing plus a sample plan within 48 hours. Contact Yongkang Tailong Kitchenware Co., Ltd. and make alloy substitution someone else's problem.
Website: www.tlcookware.com
Email: fxw@junlonga.com
Mobile:+86.13248880555
