Thermal conductivity measurements of float glass at high temperatures by needle probe method

Thermal conductivity of several soda-lime-silicate glasses, which are calle d float glasses, has been measured by a needle probe method in the temperat ure ranges from room temperature to 1173 K. Kinds of the samples were the o rdinary clear float glass (CFL), bronze (BFL), gray (GFL), blue (HFL) and g reen (MFL) glasses, Experimental results showed that the thermal conductivi ty of the glasses increased gradually with rise of temperature in the range s from room temperature to 1173 K. Thermal conductivity values of the glass es measured do not depend on the kinds of samples, and it is considered tha t the measured values are real thermal conductivity, The values of conducti vity of the glasses measured were about 1.0 W/(m(.)K) at 303 K, 1.3 W/(m(.) K)at 773 K, 1.4 W/(m(.)K) at 973 K and 1.7 W/ (m(.)K) at 1173 K.