Topline Tempered Glass is made from the thermal process of heating up the annealed glass surface at very high temperature near to its softening point, thereafter rapidly cooled by streams of uniform cold air onto the glass surface simultaneously. The end result gives additional strength and impact resistance to the heat treated glass. Topline Tempered Glass is about five times stronger than annealed glass of the same type and thickness. Once breakage occurs, it shatters into multiple pieces of fragments, reducing the risk of serious injury. Topline Tempered Glass is also classified as SAFETY GLASS.
Topline Tempered Glass is approximately three to five times stronger than normal annealed glass.
THERMAL STRESS RESISTANCE
It is three to five times above the thermal shock resistance of annealed glass, and can withstand abrupt changes of temperature without breaking.
Topline Tempered Glass is considered as safety glass. When it breaks, it shatters into multiple small fragments which does not cause serious bodily injuries.
- Curtain wall
- Wall cladding
- Glass facade
- Shop fronts
- Escalator side panels
- Frameless glass door
- Shower screen / door
- Glass table
- Table Top
Tempered Glass may occasionally shatter spontaneously for no apparent reason, eventhough it has been installed for some time. This spontaneous breakage could be due to the presence of nickel sulphide in the glass production, it is indeed difficult to ascertain the actual cause of the breakage.
Therefore,TOPLINE HEAT-SOAK TEST is a very much recommended process where the tempered glass is placed in the heating chamber and heated to 290°C (+/- 10°C), for 2-8 hours so as to induce the glass with nickel sulphide to break spontaneously. This helps to reduce risk of breakage on site.
Method of manufacturing Topline Heat Strengthened Glass is similar to Tempered Glass, except that the Heat Strengthened Glass is cooled less rapidly. Heat Strengthened residual surface compression level is within the range of 4,000psi to 7,000psi, and thus Topline Heat Strengthened Glass is twice as strong and withstand stronger impact, compared to ordinary glass. When the glass breaks, the pattern is similar to ordinary glass, but the fragments of Strengthened Glass lock together and remain in the frame. Topline Heat Strengthened Glass also offers good resistance to thermal stress, though the resistance is less than Tempered Glass.
Topline Heat Strengthened Glass is two times mechanically stronger than annealed glass of the same size and thickness.
RESISTANCE TO THERMAL SHOCK
Most glasses used on facade and window glazing have high energy absorption factor which may cause glass breakage due to thermal shock. However, Topline Heat Strengthened Glass is able to withstand high temperature changes.
LOW SURFACE DISTORTION
Due to its lower processing temperature/cooling pressure, Topline Heat Strengthened Glass has less optical distortions than tempered glass. Strengthening method improves the smoothness and optical quality of processed glass.
LESS TENDENCY OF SPONTANEOUS BREAKAGE
“Spontaneous Breakage” occasionally happens in tempered glass due to the possible presence of nickel sulphide. The Topline Heat Strengthened Glass is less sensitive to this problem.
- Building facades
- Spandrel Glass
- Commercial Buildings
- Combination with Laminated Glass
- Use in exterior and interior of Double Glazing Units