Method 1: pour hot water into the thermos cup, and feel the temperature on the surface of the cup with your hands. If it is a true thermal insulation Vacuum cup, the surface temperature will not change, but if it is a false thermal insulation Cup, it is not vacuum treatment, with the passage of time, the surface of the thermal insulation cup will heat, this is because the heat release heat through the thermal conductivity of metal, and do not play the role of insulation, only a double vacuum. The heat preservation cup can prevent the heat from distributing.
Method two: look at the weld and interface of the cup. Without a weld, the thermal insulation cup with a uniform body has better thermal insulation effect. If it is found that there is a weld on the cup of the thermos cup, the insulation degree of these thermos cups will be greatly discounted.
In general, the ingenious selection of a thermos cup is as follows:
1. see: look at the appearance of the cup, including the production process and interface of the cup, the formal certificate is very important.
2. shake: in order to avoid buying a cup of low quality silt in the cup, shake the cup at the time of purchase, and don't buy it if you hear the sound of silt in the cup.
3. pinch: good stainless steel insulation cup surface material is thick, not easy to deform, if in the purchase of the cup surface, found more soft, easy to sag, the quality of these insulation cup is not passed.