A New Way of Heating Glass
Everyone in the glass business knows how space and time-intensive melting and processing glass is, where every degree or minute saved is valued. Long furnaces, hours in autoclaves, huge glass melting tanks…
A new way of heating glass promises to change all that with the possibility of single-site heating and bending; continuous line, autoclave-free laminating; and almost on-demand glass melting that transforms tube and fiber production into a rapid, flexible process. The big production problem with conventional heaters is that glass cannot be heated fast without cracking from the internal temperature differential. The maximum heating rate for a 4 mm glass sheet, for example, is 6 C/s-100C/s. Even this low rate requires a high uniformity heat source–not a simple task– because conventional energy sources like infrared or hot air are highly non-uniform in themselves. To achieve high production, billions of BTUs are wasted by tunnel furnaces that heat rollers, shelves, walls, and, indirectly, whole plants. Slow heating also has its own drawbacks, like optical and geometrical distortion, mineral leaching, loss of flatness and strength, and destruction of coatings, to name a few. So a radical departure from this whole model would be needed to break through to better thermal processing.
