玻璃钢化加热过程的初步分析

Preliminary Analysis of Heating up Process for Glass Tempering

为加深对玻璃钢化过程的认识,提高工艺参数调控的合理性,建立了钢化炉加热段中玻璃板加热升温过程的数学模型,并用数值方法进行了求解分析。玻璃厚度、表面辐射率、加热方式对玻璃板加热过程有重要影响。计算得到的不同厚度的玻璃板加热到既定温度所需时间与工厂生产实践的数据基本吻合。结果表明,加热Low-E玻璃宜采用对流辐射加热模式,对流传热系数应控制在50W/(m2.℃)左右。加热初期,玻璃板内的温差可达82℃(对6mm厚玻璃),采用双室式加热是合理的。

In order to deepen understanding of the glass tempering process and reasonably to adjust the process parameters, simple methatical models of glass plate heating up process in heating zone of tempering furnace have been set up and solved numerically. Calculated results show that the thickness and thermal emissivity of glass plate, and the heating method have substantial effects on heating up process of glass plate. The calculated times required for heating glass plate to the specified temperature for diffferent thickness of glass plate are in reasonable agreements with the data obtained from factories. The combined heating method of convection into radiation with a convection coefficient of 50W/（m2 ·℃ ） is suitable for the heating of Low-E glass. The temperature difference between the surface and centre of glass plate is great at the beginning of heating up and could reach 82℃ for ordinary 6 mm glass. Therefore, a double chamber design for heating is desirable.