Fiberglass, also called fibrous glass, is glass in the form of fine fibers (threads). The fibers may be many times finer than human hair, and may look and feel like silk. The flexible glass fibers are stronger than steel, and will not burn, stretch, rot, or fade.
Uses.
Manufacturers use fiberglass to make a variety of products. It is woven into cloth for such products as curtains and tablecloths. The cloth will not wrinkle or soil easily, and it needs no ironing. Fiberglass textiles are also used for electrical insulation. In bulk form, it is used for air filters and for heat and sound insulation. Air trapped between the fibers makes it a good insulator.
Fiberglass reinforced plastics are extremely strong and light in weight. They can be molded, shaped, twisted, and poured for many different uses. Manufacturers use them to make automobile bodies, boat hulls, building panels, fishing rods, and aircraft parts. The fibers used to strengthen plastic may be woven or matted together, or they may be individual strands.
How fiberglass is made.
Fiberglass is made from sand and other raw materials used to make ordinary glass (see Glass (Composition of glass)). Strands of fiberglass may be made in different ways. In one method, the raw materials are heated and formed into small glass marbles so workers can examine them for impurities. The marbles are then melted in special electric furnaces. The melted glass runs down through tiny holes at the bottom of the furnace. A spinning drum catches the fibers of hot glass and winds them on bobbins, like threads on spools. Because the drum revolves much faster than the glass flows, tension pulls the fibers and draws them out into still finer strands. The drum can pull out 2 miles (3.2 kilometers) of fibers in a minute. Up to 95 miles (153 kilometers) of fiber can be drawn from one marble 5/8 inch (16 millimeters) in diameter. The fiber can be twisted together into yarns and cords. The yarns may be woven into cloth, tape, and other kinds of fabrics. In another method, called the direct melt process, the marble-making steps are omitted.
Bulk fiberglass, or fiberglass wool, is made somewhat differently. Sand and other raw materials are melted in a furnace. The melted glass flows from tiny holes in the furnace. Then high-pressure jets of steam catch it and draw it into fine fibers from 8 to 15 inches (20 to 38 centimeters) long. The fibers are gathered on a conveyor belt in the form of a white woollike mass.
History.
The Egyptians used coarse glass fibers for decorative purposes before the time of Christ. Edward Drummond Libbey, who was an American glass manufacturer, exhibited a dress made of fiberglass and silk at the Columbian Exposition in Chicago in 1893. During World War I (1914-1918), fiberglass was made in Germany as a substitute for asbestos. During the 1930’s, the Owens Illinois Glass Company (now called Owens-Illinois, Inc.) and the Corning Glass Works developed practical methods of making fiberglass commercially.
