I. 304 or 316 is better for vacuum flasks
304 stainless steel and 316 stainless steel are both American standard austenitic stainless steels, both of which are resistant to air, steam, Weak corrosive media such as water or stainless steel. In addition, 304 stainless steel is a food-grade stainless steel approved by the state. It is often used in stainless steel tableware, kettles, thermos cups, etc. In order to maintain the inherent corrosion resistance of stainless steel, the steel grade must contain more than 18% chromium and more than 8% nickel. Therefore, most cups are marked with 304.
The density of 304 is 7.93g/cm3, also known as 18/8 stainless steel in the industry. As a widely used steel, it has good corrosion resistance, heat resistance, low temperature strength and mechanical properties; good hot workability such as stamping and bending, no heat treatment hardening phenomenon, no magnetism, operating temperature -196℃—— 800°C.
316 stainless steel is used in food industry, medical equipment, etc. In comparison, both are austenitic stainless steels. The nickel content of 316 stainless steel is about 16%-18%, while that of 304 stainless steel is only 8%-12%. The molybdenum content of 316 stainless steel is 2% higher than that of 304 stainless steel. Therefore, the corrosion resistance of 316 stainless steel is better than that of 304 stainless steel, especially the resistance to chlorine corrosion. In general, 316 has more molybdenum than 304, so its corrosion resistance, atmospheric corrosion resistance and high temperature strength are particularly good. Generally, the high temperature resistance can reach 1200℃-1300℃, and it can be used freely even under very harsh conditions. Basically, there is no phenomenon of thermal expansion and cold contraction. If the economy allows, it is recommended to choose a 316 stainless steel thermos.
2. Precautions for the use of vacuum thermos
1. Before using the new product, it must be scalded with boiling water (or washed several times with some edible detergent) , for high temperature disinfection.
2. Before use, please preheat (or pre-cool) with boiling water (or cold water) for 5-10 minutes to make the heat preservation effect better.
3. Please overfill the water in a hurry to avoid scalding from the overflow of boiling water when the lid is tightened.
4. Please drink slowly when drinking hot drinks to avoid burns.
5. It is not advisable to store carbonated beverages such as milk, dairy products and fruit juices for a long time.
6. After drinking, please tighten the lid of the cup to ensure hygiene and cleanliness.
7. Use a soft cloth and food detergent diluted with warm water when cleaning. Do not use alkaline bleach, metal dishcloths, chemical rags, etc.
8. The inner side of the stainless steel cup sometimes produces some red rust spots due to the influence of iron and other substances in the contents. It can be soaked in warm water and diluted vinegar for 30 minutes, and then fully cleaned.
9. In order to prevent the generation of peculiar smell or stains, and it can be used for long-term cleaning. After use, please wash and dry thoroughly.
