Читать книгу Encyclopedia of Glass Science, Technology, History, and Culture - Группа авторов - Страница 140

The production of glass fibers encompasses a wide range of processes, from raw‐material sourcing, batch weighing and mixing, batch‐to‐glass melting and fining, fiber drawing with the application of a water‐based organic sizing, to finally drying. Much of today's glass‐fiber production for reinforcements incorporates direct processing wherein the finished product, whether wound into a continuous spool of fiberglass strand or chopped directly after the fibers are formed and coated with sizing, is produced in one step as a part of the forming operation. Secondary downstream processes are still in use for some applications and may include twisted yarn on bobbins, roving packages made by assembling collections of smaller strands into larger strands, fibrous mats made from chopped or continuous strands bound together by mechanical or chemical binders, and chopped products for some specialty applications. The general process is sketched in Figure 2. For E‐glass fiber production, combustion technology is moving from natural gas–air or oil–air to natural gas–oxygen to achieve better energy transmission efficiency. Where C‐glass fiber is still in production, the use of syngas remains prevalent for furnace and combustion systems because of lower capital costs. For both types of fibers, electric boost technology has increased in utilization for energy efficiency and for lowering top firing and hence lowering the crown temperature of the furnace to prolong its life. The following sections briefly discuss some of the key areas of glass melting/fining, fiber drawing, and sizing chemistry design.

Figure 2 Schematic illustrations of continuous fiberglass manufacturing processes: (a) batch operation, batch melting/glass fining, and glass delivery to bushing positions, common burner locations used in the primary canal and forehearth (not shown) and (b) steps in fiber drawing and downstream processes.

Source: Fiber glass market study, PPG, 2014

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