The stainless vacuum flasks have become a must-have item in our lives. Whether you are a front-line worker in the workshop or a first-line star all over the world, you will use stainless vacuum flasks, but the price of the products you choose is different. The price is different, so the quality of the vacuum flask is definitely different. Today we will take a look at how to discriminate the quality of the stainless vacuum flask.
The steel material used in the stainless vacuum flask belongs to food-grade stainless steel. Food-grade stainless steel refers to the part of food machinery that contacts food, and must meet certain food safety requirements. Because a lot of acid and alkali are used in the food production process, and stainless steel contains chromium, unqualified stainless steel will dissolve chromium in various price levels, which is toxic; and it is required to limit the content of various alloy impurity elements such as lead and cadmium.
Food-grade stainless steel does not note the model, but depends on whether there is a food-grade stainless steel mark on the vessel, that is, the GB9864 stainless steel mark. In addition, the American Asme standard has a designation for stainless steel, and the common ones are 304, 306, 316, etc., and these are all stainless steel models, not necessarily food-grade stainless steel models.
The color of the ordinary ss vacuum flask is whitish and dark. If it is soaked in salt water with a concentration of 1% for 24 hours, rust spots will occur. Some of the elements contained in it exceed the standard, which directly endangers human health.
The depth of the inner tank is basically the same as the height of the outer shell (the difference is 16-18mm), and the capacity is in line with the nominal value. Some poor quality vacuum flask add sand and cement blocks to the cup to make up for the missing weight. Myth: A heavier cup (pot) is not necessarily better.
The characteristics of food-grade new plastics are small odor, bright surface, no burrs, long service life, and not easy to age. Ordinary plastics or recycled plastics are characterized by strong odor, dark color, many burrs, and plastics are easy to age and break.
The simple discrimination method of thermal insulation performance: Pour boiling water into a stainless vacuum flask, tighten the cork or lid clockwise for 2-3 minutes, and then touch the outer surface of the cup body with your hands. The product has lost the vacuum degree and cannot achieve a good thermal insulation effect.
The discrimination of sealing performance: after adding water to the cup, tighten the cork and lid in a clockwise direction, place the cup flat on the table, and there should be no water leakage; the lid and the mouth of the cup should be flexibly screwed without gaps.
The above content is about how to identify the quality of the vacuum flask that needs attention. The important thing to buy a stainless vacuum flask is to identify the brand, so as to reduce the chance of inferior products and buy a regular and qualified stainless vacuum flask.