Heat Strengthened Glass is manufactured similarly to Tempered Glass, except the glass is cooling less rapidly. Heat Strengthened residual surface compression level is within 4,000psi to 7,000psi. Heat Strengthened Glass is twice as strong and possesses greater impact compared to ordinary glasses. When broken, the pattern is similar to ordinary glasses but the fragments lock together and remain in the frame. Heat Strengthened Glass offer good resistance to thermal stress, although less than Tempered Glass.
Heat Strengthened Glass
Heat Soak Glass
Heat Soak Test (HST) was introduced to check for the presence of Nickel Sulfide (Nis) will break in the Heat Soak Oven. Therefore, the chance of spontaneous breakage of the Tempered Glass after HST due to the pressure of Nis should be reduced to the minimum.