The mould used for blow molding is produced by extrusion. The production process is divided into two kinds: continuous and intermittent. Continuous extrusion blow molding is to use the extruder to continuously manufacture the billet ([continuous extrusion blow molding] continuous extrusion blow molding), the billet one by one into the open mold on a rotary table, and then the closing mold, blowing, cooling, ejecting and other operations. This method is used for the rapid production of small products, such as bottles. Intermittent extrusion blow molding, usually used to produce large products. Because large products require more raw materials, so the use of storage cylinder head. After the plastic melt from the extruder is stored to a certain amount in the storage cylinder, the tubular plunger is lowered by hydraulic pressure, and the melt is pressed out through the mouth. The formed billet is then molded by the general blowing method. In this method, the die resistance is small, the material is pressed fast, the sag phenomenon of the billet is small, and the wall thickness of the product is evenly distributed. It is often used to produce large containers of polyethylene with high molecular weight. Suzhou blow molding processing
Blow molding toy hollow blow molding blanks are obtained by injection molding. The billet is left on the core mold of the mold, and then the billet is transferred to the blow mold, the compressed air is passed from the core mold, the billet is blown, cooled, and then transferred to a station for demoulding, and the product is obtained. The advantages of this method are uniform wall thickness, small weight tolerance, less post-processing and less waste edge. However, when blowing large parts, the mold cost is high. Therefore, it is suitable for the production of small fine products with large batches.
