At present, there are mainly 304, 201 and 301 materials on the market. If the content of chromium and nickel is different, there will be differences. Material 304 contains chromium 18 and nickel 8-9, while materials 201 and 301 only contain chromium 14 and 16 and nickel 1 and 5 respectively. It has been scientifically proven that stainless steel pipes with high chromium and nickel content and good smelting technology have better performance, stronger corrosion resistance, and stronger finish durability.
At present, the raw materials are imported and produced by large and small domestic manufacturers. Although they are all made of 304, each manufacturer has different smelting technology, various chemical element content indicators, different quality, and a price difference of about 10%. Moreover, there are quality differences in the manufacturing process of each pipe factory, and the performance and corrosion resistance after use are also strong or weak. Even if the poor quality does not rust in the near future, it will become gray, dark, and even rust after a long time.
- Identify whether the stamped material “304” is stamped on the pipe surface, and ask for the manufacturer’s quality certificate and quality assurance certificate.
- Test with an acidic reagent. After 30 seconds, the material 304 will not change color, and the material 201 will change color.
- Check whether the color of the outer surface and the inner wall of the tube is bright and smooth, whether the thickness is uniform or rough.
- When purchasing, you should choose famous brand products above the provincial level that have been evaluated by the Bureau of Quality and Technical Supervision. It is the most direct and effective choice to have long-term use testimony and good reputation among customers.