Plastic profile extrusion process - Plastic profile extrusion process Plastic profile extrusion process according to the forming state of the co-extrusion material can be divided into two categories: before co-extrusion and after co-extrusion. Pre-co-extrusion refers to the realization of composite molding of two kinds of materials in the process of incomplete molding; After co-extrusion refers to a material has been fully formed, and then with another material to achieve composite molding. The advantage of the rear co-extrusion is that it can use the waste material and the economy is better.

The extrusion process of plastic profiles can be divided into organic co-extrusion and inorganic co-extrusion according to the different extrusion materials. Organic co-extrusion includes the same material before co-extrusion (such as fine material and mixed with recycled material before co-extrusion) and different materials before co-extrusion (such as PMMA and PVC before co-extrusion) and soft and hard PVC after co-extrusion; Inorganic co-extrusion can be divided into aluminum - plastic composite co-extrusion and steel - plastic composite co-extrusion.

This paper focuses on the co-extrusion, aluminum - plastic composite profile co-extrusion, steel - plastic composite profile co-extrusion and two-color co-extrusion technology.

Compared with the traditional pre-co-extrusion (FCE) technology, the post-co-extruded plastic profile extrusion process has the advantages of simple process, flexible application, low rejection rate, easy recovery and controllable bond strength. At present, the technology is mainly used in the manufacture of Windows and doors profiles with sealing strips.

The traditional pre-co-extruded plastic profile extrusion technology is one - time molding technology. The molten material with different rheological behavior or different color is extruded from two or more extruders to the same forming mold. The melt flows in its own flow channel in the forming mold, and then merges and extrudes at the mouth mold, and vacuumes in the shaping sleeve, cooling and shaping.