Glass fiber can be divided into continuous fiber, fixed-length fiber and glass wool according to form and length; according to the glass composition, it can be divided into alkali-free, chemical-resistant, high alkali, medium alkali, high strength, high elastic modulus and alkali resistance ( Anti-alkali) glass fiber and so on.
The main raw materials for the production of glass fiber are: quartz sand, alumina and pyrophyllite, limestone, dolomite, boric acid, soda ash, Glauber's salt, fluorspar and so on. The production methods can be roughly divided into two categories: one is to directly make molten glass into fibers; the other is to make molten glass into glass balls or rods with a diameter of 20mm first, and then heated and remelted in various ways to produce a diameter of 3~ 80μm very fine fiber. The infinitely long fibers drawn by the mechanical drawing method of the platinum alloy plate are called continuous glass fibers, which are generally called long fibers. Non-continuous fibers made by rollers or air flow, known as fixed-length glass fibers, are commonly referred to as short fibers.
Fiberglass is divided into different grades according to composition, nature and use. According to the standard level regulations (see table), Class E glass fiber is most commonly used and widely used for electrical insulation materials; S class is special fibers.