Studies in the Distribution of Temperature through Molten Glasses in a Tank Melting Furnace. Part III. The Effect of Glass Composition

JSGT 1946 V30 T343-T355

 The effect of basic glass composition on the temperature distribution through molten masses of glass in a laboratory tank furnace has been studied for four colourless glasses-namely, a lead crystal-, a bottle-, a Pyrex- and an alumino-borosilicate glass. The temperature gradients, determined at the centre of the mass of glass by the temperature drop in passing vertically from 3 in. to 4 in. depth, were 10, 10, 5 and 10° per in., respectively. The calculated overall heat transmission for the four glasses was 59, 60, 63 and 59 per cent, respectively. Thus basic glass composition as such has no appreciable effect on the temperature distribution through molten glass except in so far as it affects the state of oxidation of any colouring oxides present. Thus the Pyrex glass with a total iron oxide content higher than that of the other three glasses had the lowest temperature gradient and the highest overall heat transmission due to the fact that it contained the lowest proportion of ferrous oxide.

R. S. Allison, R. Halls & W. E. S. Turner