Tempered glass is manufactured through heating common glass uniformly to the softening point and then quenching it, causing a strong permanent internal stress in the glass, of which the internal tensile stress and external compressive stress should be in a stable tress equilibrium in order to intensify the operational strength and load carrying capacity of the glass and enhance its wind pressure resistance, weatherability and shock resistance. With high strength and thermal stability, tempered glass can be widely applied to the places with special requirements on mechanical strength and security, such as glass curtain walls, balcony doors and windows, high-grade shopwindows, shower rooms, household supplies, balustrade glass of escalators, glass partitions, the places where there are a dense crowd or humans are apt to contact with glass and vulnerable to physical injury (such as stadiums) or the places where are vulnerable to body shocks, such as doors and windows, curtain walls, automobiles, trains and ships and the places where are susceptible to the changes in temperature.