Compared with plastic injection molding machine,plastic extrusion blow molding machine has the following advantages.
1) Plastic extrusion blow molding machinery, especially cost of blow molding mold is low (similar molding, the cost of plastic extrusion blow molding machinery is about half of plastic injection molding machinery), so the production cost of the product is also low.
2) during blow molding, parison is forming through nose in the lower pressure and inflation under low pressure, and thus the residual stress of the product is small, due to high performance of tensile, impact, bending and environmental strain, is with good performance. In the injection molding, the melt under high pressure pass through the mold flow and gate, which will lead to uneven stress distribution.
3) The relative molecular mass of blow molding grade plastic such as PE is much higher than that of plastic injection grade. Therefore, blow molded products have a high impact toughness and high resistance to environmental stress cracking performance, suitable for the production of larger container or big drum packaging of detergent and chemical reagents
4) Since plastic extrusion blow molding, is composed of only female mold, it is possible to change the wall thickness of the product by simply adjusting the gap or the extrusion condition of the nose die, which is advantageous for the inability to accurately calculate the desired wall thickness. While injection molding, the cost of changing wall thickness is much higher.
5) Plastic extrusion blow molding machinery can produce products with small wall thickness, which can not be produced by injection molding.
6) Plastic extrusion blow molding machinery, can produce complex, irregular and integral products. The use of injection molding, the first to produce two or more products, through the buckle with, solvent bonding or ultrasonic welding and other combinations together.
However, the accuracy of blow molded products is generally not high in injection molding products.