Reveal the secrets of glass

Did you know there are other materials for glass? Do you know what that glass is? Do you know what high-borosilicate glass is used for? Do you know the harm of tempered glass? In fact, there are many kinds of glass materials, some glass materials are transparent, and add color glass, and many people in life still dare not use the glass to drink water, because the bottom of the cup suddenly burst the shadow exists (when I was a child with canned bottled hot water, especially in the winter is very easy to step on the thunder), so even know the glass material is more healthy and environmental protection, still dare not easily try. So today I’m going to tell you why your glass of water falls out. Is the glass safe to use?

First of all, explain the reason why the bottom of the cup cracks: easy to crack the cup such as cans or very thick cup material, the bottom of the cup is generally thicker than the body, because of the slow heat conduction of the glass, after pouring boiling water, the body of the cup is more rapid heat expansion, and the bottom of the cup heat expansion is slower, which produces shear stress, from the bottom of the cup that circle neatly split. There are also some water cup cup body burst is the same principle, the cup thickness is not uniform resulting in thermal expansion and contraction difference!

So in the purchase of glass, in the face of the most common market sodium calcium glass, tempered glass, high borosilicate glass, so what is the difference between them?

1. [The difference between ingredients]

Common sodium-calcium glass is mainly composed of silicon, sodium and calcium. High borosilicate glass is mainly composed of silicon and boron, so we can see their material composition from their two names.

2. [Performance difference]

Generally speaking, the performance of the cover glass is not as good as high borosilicate glass material, high borosilicate glass material, short molding more difficult products more or less there will be some forming defects, such as stripes, material printing and scissors printing and so on.

3. [Appearance difference]

High borosilicate glass and sodium calcium glass, if it is pressed molding, there will be no circle of cold lines, if it is other ways of molding, there will be cold lines, such as high borosilicate, usually based on artificial blowing, there will be no cold lines.

4. [Density difference]

Usually the density of high borosilicate glass is less than that of that glass, and this can be compared by means of buoyancy measurement of density.

5. [Difference in heat resistance degree]

High borosilicate glass has a strong heat resistance, and the heat resistance of the glass is relatively poor, high borosilicate glass hot and cold impact, generally in 100 degrees to 200 degrees. That glass is usually only 80 degrees.

Simply put, sodium calcium glass is ordinary glass, cup body cup bottom is very thick, its main composition is composed of silicon and sodium and calcium, high chemical stability, but poor heat resistance, do not recommend water, when cold water cup or storage tank can be assured to use;

Tempered glass is on the basis of ordinary glass added a “tempering process”, so that the glass looks bright, easy to wash, with strong, but as not heat resistant and sodium-calcium glass, there are “self-explosion” risk;

High borosilicate glass is mainly composed of silicon and boron, high borosilicate (3.3 glass) pipe and bar is a low expansion rate (thermal expansion coefficient: (0~300℃)3.3±0.1×10-6K-1), special glass material with high temperature resistance (softening point 820℃, high thermal stability, cold and hot temperature difference of 150℃), high strength, high hardness, high light transmittivity and high chemical stability, can be made very thin and transparent, and the body and bottom of the cup are formed in one piece, without the risk of bursting. In the household daily necessities industry is the use of heat-resistant glass water cup, glass tea set, etc.

The above is the difference between several common glasses on the market. I hope it will help you.