| Category | Process | Features | Concerns and Influence |
| High-end Products（Coign） | Gravity Casting Process |
- The inner walls are smooth and free of impurities.
- Average wall thickness ≥ 3.0mm
- High-quality materials create a solid, premium feel.
|
High-quality, safe product; no major issues |
| Low-end Products | Sand Casting Process + Dipping Technology |
- The interior walls are rough and unclean.
- Average wall thickness < 1.5mm
- More than 90% of products leak unless further processed. Dipping technology increased the pass rate to 90%.
|
Glue residue on the interior walls may contaminate the water, posing a health risk. |
Note:
We use gravity casting to manufacture our premium products, ensuring both high quality and safe use.
Sand casting, used in low-end product manufacturing, leads to insufficient wall thickness and rough inner surfaces. Dipping technology is applied to improve the pass rate, but residual glue negatively impacts water safety and product health standards.
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