Filament winding consists of winding continuous rovings of fiber onto a rotating mandrel in predetermined patterns.  This method of manufacturing provides the greatest control over fiber placement and uniformity of structure.  In the wet winding method, the fiber picks up resin either by passing through a resin bath or from a metered application system.   In the dry winding method, the reinforcement is in the preimpregnated form termed towpreg.  After several layers are wound, the component is cured and removed from the mandrel (or in some cases the mandrel becomes part of the component). 

Filament winding is traditionally used to produce pressure vessels, pipe, rocket motor casings, tanks, ducting, golf club shafts and other symmetric parts.  Filament winding technology has been expanded to include non-cylindrical, non-spherical composite parts thanks in part to advancements in computer and software technology.

What are Advanced Composites? 

Advanced composites are a combination of a matrix and fibers. The fibers can be carbon, graphite, Kevlar™, fiberglass or other more exotic fibers. These fibers provide the necessary strength and stiffness for the finished product. Surrounding each fiber strand is a matrix, which holds the structure together and allows the product to be formed into various shapes. The matrix is generally a polymer such as polyester, epoxy or vinyl ester, but it could be a metal or ceramic matrix in some instances. The matrix is also used to transfer loads from one fiber to another. Composites offer the unique ability to mix and match fibers and matrix materials to develop a new material with new desired properties.

Composites yield improved performance over metals.

• Stronger, stiffer and lighter than metals. At approximately half the weight of aluminum and twice the stiffness of steel, carbon fiber composites are ideal for applications such as aerospace, racing and sporting goods.

• Highly conformable. Virtually any shape is possible through filament winding, molding and bonding, allowing exceptional design flexibility.

Composites offer other unique mechanical properties.

• Low coefficient of thermal expansion (CTE).
• Very high thermal conductivity
• Negligible creep
• Improved fatigue resistance
• Non-corrosive