The temperature at which a glass is used teaches you how to distinguish a heat-resistant glass
There are two kinds of glass: high temperature resistant and high temperature resistant. Don't use high temperature resistant glass temperature is commonly - 5 to 70 degrees c, if is made of high borosilicate material high temperature resistant glass, so its use high temperature can be from 400 to 500 degrees, and can withstand the moment "-" 30 to 160 degrees Celsius temperature difference.
It is very simple to distinguish whether the glass belongs to the heat-resistant material: the surface of hot water in the heat-resistant glass is not hot, and the surface of hot water in the heat-resistant glass is hot. After separating the temperatures at which these two glasses are used, let's look at the properties of these two glasses.
The operating temperature of ordinary glass
Ordinary material glass is a poor conductor of heat, as part of the glass wall suddenly encounter heat (or cold), the inner layer of the cup is heated less obvious expansion but outer heat enough, resulting in the glass temperature difference between the parts is bigger, and due to the reason of heat bilges cold shrink of the object, which makes glass uneven heat expansion of the parts, the uneven, the difference is too big, can make the glass broken.
At the same time, glass is very rigid material, the heat transfer rate is slow, the thicker the glass, due to the influence of temperature difference, when the temperature rises fast, it is more likely to burst. That is to say, the temperature difference between the boiling water and the glass is too large to cause the glass to crack. So use thicker glass temperature generally "- 5 to 70 degrees Celsius, or add some cold water before pour boiling water, add some hot water, such as the cup warm water after pour out, add boiling water was no problem.
Use temperature of high temperature resistant glass
The greatest characteristic of high borosilicate glass is very low thermal expansion coefficient, is about a third of the common glass, also is not sensitive to temperature, no general object of the common heat bilges cold shrink, thus has high temperature resistant, high heat stability. It can be used to hold hot water.
However, small make up remind you, don't put on the market of toughened glass used as not high temperature resistant glass, toughened glass and common glass is the same temperature, the use of in 70 degrees commonly the following, need to use caution. And some experts say, there is no such thing as heat-resistant tempered glass products or toughened heat-resistant glass products in the domestic market at present, do not be misled when purchasing. If it is a heat-resistant glass, there will be a corresponding label on the glass, indicating the temperature and range of use, etc. If you find the nominal heat-resistant glass but the price is low, consider its authenticity.