摘要 |
In a proces for the thermal treatment of glass, the glass is preheated to a predetermined temp. and contacted with a gas-fluidised particulate material. The particulate material comprises a mixt. of several chosen particulate materials, >=1 of which has gas-releasing properties in contact with hot glass. The mixt. of particulate materials is chosen to have the required thermal capacity and fluidity to cause the desired thermal treatment of the glass. The process is esp. useful for hardening flat or curved glass sheets, esp. for car windscreens. The degree of hardening is controlled by the gas developing properties, heat capacity and fluidity of the fluidised particles. The movement of the particles in the vicinity of the hot glass is faster than in the body of the material due to the development of gas, thus improving heat transfer between the hot glass and the fluidised particles. |