WauTechFocusing on stainless steel processing and manufacturing
WauTechFocusing on stainless steel processing and manufacturing
1. Material selection
Food-grade stainless steel
304 (06Cr19Ni10) : General-purpose material with good corrosion resistance.
316 (06Cr17Ni12Mo2) : Higher corrosion resistance, suitable for high-end cups and seawater environments.
430 (10Cr17) : Low cost, but poor corrosion resistance (prone to rust).
Avoid using 201/202 (which has a relatively high manganese content and may leach out heavy metals).
2. Process control of processing
Anti-pollution
Special for processing equipment (avoid mixing with carbon steel to prevent iron ion contamination).
After stamping and welding, cleaning and passivation (nitric acid + hydrofluoric acid solution) are required.
Dimensional accuracy
The clearance between the cup body and the lid is no more than 0.1mm (to prevent water leakage).
3. Food safety
Compliant with national standard: GB 4806.9-2016 "Metallic Materials and Articles for Food Contact".
Testing items
Heavy metal migration (lead, cadmium, nickel, etc.).
Surface roughness (Ra≤0.8μm, easy to clean).
Ii. Common Problems and Solutions
| Problem | Reason | Solution |
| The cup body is cracked | Insufficient stamping lubrication/Die wear | Replace the high-lubrication stamping oil and repair the die |
| The weld seam is black. | Severe oxidation during welding | Improve the purity of argon gas (≥99.99%) and perform acid washing after welding |
| Burrs on the rim of the cup | The trimming is not thorough | Add polishing or rolling processes |
| The thermos is leaking air | Poor vacuum brazing | Test the airtightness of the weld seam and optimize the welding parameters |
Iv. Industry Trends
Environmental protection process: Reduce acid washing and adopt electrolytic polishing or ultrasonic cleaning.
Smart cup body: Laser engraving + sensor embedding (such as temperature display).
Lightweight: Ultra-thin stainless steel (0.2mm) + laser welding technology.
Summary
The processing of stainless steel cups needs to take into account three core aspects: materials, techniques and safety. In particular, food-grade products must comply with the GB 4806.9 standard.
