1. The main difference is that the lead content in food -grade stainless steel materials is relatively low, and non -food -grade stainless steel also contains toxic elements.
2. Food-grade stainless steel refers to the "National Standard/Stainless Steel food vessels Sanitation Standard" of the People's Republic of China. Stainless steel materials specified in GB4806.9-2016 are much lower than general stainless steel.Because the food production process should be used for a lot of pH, stainless steel contains chromium, and unqualified stainless steel will dissolve chromium at various prices, which are poisonous; and the content of various alloy impurities such as lead and cadmium is required.
3. The term "stainless steel" is not just a kind of stainless steel, but it means more than 100 kinds of industrial stainless steel. Each stainless steel developed has good performance in its specific application field. The key to success is first to clarify the purpose, and then determine the correct steel species. There are usually only six steel species related to the application of architectural structure applications. They all contain 17 to 22%chromium, and better steel species also contain nickel. Add molybdenum can further improve the corrosion of the atmosphere, especially the corrosion resistance to the atmosphere of chloride.
What is the difference between food grade 304 316 grade stainless steel and ordinary 304 316 grade stainless steel?
1. Different use standards 304 316 grade food-grade stainless steel water pipe standards are GB/T29038-2012 (drinking water pipe) standard. The migration of heavy metals such as nickel, sulfur, phosphorus, lead, and 6 -valent chromium is within the scope of standards. Long -term use will not cause scaling and will not be easily contaminated by bacteria. There is no need to worry about the impact of water quality, and it can also prevent the secondary pollution of the water. Ordinary stainless steel decorative pipes adopt GB/T18705-2002 (decorative water pipe) standard. It cannot be directly contact with food for drinking water pipes.
2. Compared with ordinary stainless steel decorative tubes, 304 316 grade food -grade stainless steel water pipes are more resistant to high temperature. It can withstand the temperature of up to 80OC. Ordinary stainless steel decoration pipes may be damaged at this temperature.
3. Different corrosion resistance. 304 316 grade food -grade stainless steel water pipes are the most widely used chromium nickel alloys, so their chemical properties are relatively stable. Therefore, in terms of corrosion resistance, 304 316 grade food -grade stainless steel water pipes have good corrosion resistance, while ordinary stainless steel decoration The possibility of aging will appear after a long period of use.
4. Different production processes. 304 316 grade food-grade stainless steel water pipes. The small specifications are DN15, and the wall thickness is 0.6mm-0.8mm. The quality requirements of welded seams are high, and the performance requirements of flattening, expansion, dome, and stretch testing are high. The test water pressure requirements are greater than 2.5MPa, and the general production efficiency is 1.5m/m IN. Sometimes water pressure testing is performed. The wall thickness of ordinary stainless steel decoration tube is not clear, the quality requirements of the weld are not high, the pressure requirements for pipelines are not clear, the production speed is fast, and the production efficiency can reach 20 meters/minute.
5. Different 304 316 grade food -grade stainless steel water pipes are mainly used in the fields of drinking water pipes, water supply pipelines, gas pipelines, food processing and transportation pipelines; ordinary stainless steel decoration pipes are mainly used in industrial and home decoration.
304 316 grade stainless steel is the food grade? Stainless steel 304 316 grade does not belong to the food grade. Food-grade stainless steel refers to the "National Standard/Stainless Steel food vessels Sanitary Standards" stipulated in the "National Standard/Stainless Steel food Hygiene Standard" regulations.