1) dry winding adopts prepreg yarn or belt treated with prepreg glue, which is heated and softened to viscous flow state on the winding machine, and then wound to mandrel. Because prepreg yarn (or strip) is a professional production, it can strictly control the resin content (accurate to less than 2%) and prepreg yarn quality. Therefore, dry winding can accurately control product quality. The main characteristics of dry winding process are high production efficiency, winding speed up to 100 ~ 200m/min, clean winding machine, good labor hygiene conditions and high product quality.
The disadvantage is that winding equipment is expensive and prepreg manufacturing equipment needs to be added, so the investment is large. In addition, the interlayer shear strength of dry winding products is low.
(2) wet winding means that the fiber bundle (yarn belt) is soaked in glue and wound directly to the mandrel under tension control. The advantages of wet winding are: (1) the cost is 40% lower than dry winding; (2) good air tightness of the product, because the winding tension makes the excess resin glue liquid bubbles out, and fill the gap; (3) fiber arrangement parallel degree good; (4) wet method winding, the fiber on the resin glue solution, can reduce fiber wear; (5) high production efficiency (up to 200m/min).
The disadvantages of wet winding are: (1) resin waste, poor operating environment; (2) glue content and product quality is not easy to control; (3) for wet winding resin varieties.