FRP pultrusion processing

The fiberglass composite material pultrusion molding process is a process method of producing composite material profiles by impregnating continuous fibers or their fabrics with resin and curing the resin by heating the molding die under the traction of traction equipment.

The process of pultrusion technology can be briefly divided into three steps: infiltration, forming, solidification/cooling. Compared with other composite material production technologies, its main advantages are as follows:

1. High utilization rate of raw materials

Compared with the traditional lay-up technology, the pultrusion molding technology does not need to cut the sheet-like fiber material or prepreg, and directly uses the raw silk and the prepreg tape for production, except for a small part at both ends of the profile that needs to be cut off (cut off The length depends on the length of the initial drawn fiber and the length of the curing mold), and the production process does not generate other waste materials.

2. Can produce complex structural profiles

In the engineering field, winding technology and weaving technology are also suitable for profile production. Due to the limitation of working principle, the above two technologies can only produce single-cavity simple cross-section profiles, and it is relatively difficult to arrange longitudinal reinforcing fibers. However, pultrusion technology cannot effectively produce variable cross-section profiles for the time being.

3. High production efficiency:

Pultrusion molding technology is an automatic or semi-automatic assembly line production, which has two functions of "forming" and "curing" at the same time, and can realize continuous production. The pultrusion speed can reach 10 meters per minute, which is unmatched by other "forming-curing" fiber composite production technologies.

4. Excellent quality

Through automated equipment, process parameters such as profile traction, longitudinal preload, winding/braiding preload, mold temperature distribution, resin injection pressure, and pultrusion speed can be precisely controlled during the production process to ensure overall quality uniformity and controllability. In addition, when the profile is cured, it is covered by the outer mold. After curing, the overall size tolerance of the profile is small and the surface quality is high.

5. High flexibility

By using different fiber materials and substrates (such as ultra-high modulus unidirectional fiber or multiaxial fiber, thermosetting resin or thermoplastic resin, etc.), pultrusion technology can produce products with different applicability according to different needs.