What is tempered Glass and semi-tempered glass? What are their characteristics?

Through heating process and rapid cooling treatment, to make the glass surface have even pressure and stress, and the inner have even tensile stress, then bring better flexility and numerous larger strength to the glass. It is like that, two sides of the heat strengthened glass is like the spring net which shrink to the middle, but the middle layer in the inner part is like the spring net which expand to the outside. When the tempered glass is bending, the spring net on the outside surface will be stretched, then the glass could be bent in a larger radian without broken, this is the source of toughness and strength. If some special reason destroy the spring net with balanced tensile force and pulling force, the tempered glass will broken into fragments.

tempered-glass-broken

The tempered glass have followed features,

First, good security. The strength of the tempered glass is 3~4 times larger than normal float glass, the flat shape will break into small fragments, to minimize the destructiveness which is because of the broken fragments drop or splash, then the toughened glass belongs to the safety glass.

Second, good thermal stability. The tempered glass have good thermostability, even there is 200℃ temperature difference on one tempered glass piece, it won’t break because of the heat difference.

Third, there is Spontaneous explosion in the tempered glass. The tempered glass panels maybe break even it is stored naturally. And the flatness of the tempered glass is not good as non- tempered glass.

Semi-tempered glass is between the normal float glass and tempered glass, its’ strength is 2 times larger than non-tempered glass, the size of broken fragments is also larger than tempered glass, then it is not the safety glass. The flaw of the semi-tempered glass after broken won’t cross, but when installed the semi-tempered glass with clamp or frame, every broken pieces will be fixed by the edges, won’t drop or scratch people, then the semi-tempered glass have a certain security.

The thermal stability of the semi-tempered glass is weaker than tempered glass, it won’t break with the temperature difference ups to 100℃ on one semi-tempered glass piece. But the biggest advantage of the semi-tempered glass is without Spontaneous explosion. And the flatness for the heat strengthened glass is better than tempered glass.

 semi-tempered-glass

Please note that, the glass thickness is thinner than 8mm could be made into semi-tempered glass. If the thickness is thicker than 10mm, it is hard to be made into semi-tempered glass. Even the thickness larger than 10mm could be heat treated in the glass tempering furnace, when take it out, maybe it is not float glass or semi-tempered glass, or couldn’t meet any glass standards.


Post time: Jul-29-2022