What is the reason why the newly purchased thermos cup is not insulated

In the previous article, I taught you how to easily and quickly determine whether the thermos cup is insulated when you buy it offline. I also taught you that if the outside of the thermos cup you purchased starts to heat up soon after pouring hot water into it, it means that the thermos cup is not insulated. . However, some friends still ask why the newly purchased thermos cup is not insulated? Today I will tell you what are the common reasons why a new thermos cup does not keep heat?

First of all, the production is not carried out in strict accordance with the standards. This is the main reason why the thermos cup is not insulated. Whether the production of thermos cups is made by welding water expansion process or stretching process is inseparable from the welding of the inner and outer cup bodies. At present, most water cup factories use laser welding. The welded cup body will be installed with a getter and placed High-temperature vacuuming is performed in the vacuum furnace, and the air between the double layers is discharged through high-temperature processing, thereby forming a vacuum state to isolate the conduction of temperature, so that the water cup has the ability to maintain heat.

The two most common situations are poor welding quality and leakage and broken welding. In this case, no matter how much vacuuming is done, it is useless. Air can enter the leaked area at any time. The other is insufficient vacuuming. In order to reduce costs, some factories stipulate that vacuuming can take 4-5 hours at a given temperature to be complete, but they think it should be shortened to 2 hours. This will cause the water cup to be vacuumed incompletely, which will cause Directly affects the performance of thermal insulation.

Secondly, the unreasonable shape and structure of the product results in poor thermal insulation of the water cup. The shape design is one aspect. For example, the square stainless steel thermos cup usually has a mediocre thermal insulation effect. Also, the distance between the inner and outer layers of the water cup must be at least 1.5 mm. The closer the distance, the thicker the cup wall material needs to be. Some water cups have structural design problems. The distance between the two layers is only less than 1 mm, or even due to rough workmanship. As a result, the inner and outer walls overlap, and the thermal insulation performance of the water cup will deteriorate.

Finally, the water cup is deformed due to backlog and impact during transportation, which affects the heat preservation function of the water cup. Of course, there are some other reasons that can also cause the insulation performance of the thermos cup to deteriorate, but these are the three situations that consumers are most exposed to on a daily basis.