意甲下注In the field of Dalian hollow moulding products, the proportion of multi-layer co-extrusion blow moulding hollow products with high barrier is increasing. Its moulding process is to extrude and blow several different raw materials with composite die. This kind of hollow container has good barrier effect to CO2, O2 or gasoline. The helical mandrel assembly system should be highly adaptable.
意甲下注At present, multi-layer structure can reach up to seven layers, which meets the needs of special products. Therefore, the system is preferred by multi-layer co-extrusion die because of its excellent processing conditions. The rheological design of multi-layer co-extrusion die is the key in the design. It is required to have good self-cleaning function at low extrusion volume and small shear heat at high extrusion volume.
Large multi-layer co-extrusion hollow plastic moulding machine adopts a storage head. The structure is that the main head is placed above the heads of each layer, and a concentric ring piston is equipped. The head and the storage chamber are integrated to achieve high-speed extrusion of parison at low pressure. When designing extruders adapted to these plasticizers, the number and type of extruders needed should be determined.
The design principle of the extruder is that it can meet the plasticizing requirements of different flow rates and materials, and its productivity should be higher than that of the standard extruder; the structure of screw and barrel varies with the nature of the processed materials; each extruder should be equipped with an automatic quantitative feeding hopper to accurately control the feeding amount.
意甲下注In order to improve the performance of the storage head, it is necessary to develop a storage head with high performance and double-layer heart-shaped envelope channel. Because first-in-first-out, fast color changing and material changing and easy cleaning are important features of high-performance storage head, advanced CAD/CAE/CAM technology should be actively applied in the process of producing machine, and high-quality steel and precision processing equipment should be adopted.