In the plastics industry, everyone will hear the term of blow molding. What is blow molding?Do you really know? Today, Yankang will take you to know more about it.
What is blow molding?
Blow molding is a method of forming hollow products by means of gas pressure to blow and swell hot melt embryos closed in the mould. The hollow blow molding is to extrude from the extruder and put the tubular thermoplastic blank which is still in the softening state into the molding mould.Then through the compressed air, using the air pressure to deform the blank along the die cavity, thus blowing into a short neck hollow products.
Hollow blow molding is the most important forming technology for producing hollow plastic products. Almost all thermoplastics can be used for hollow blow molding, such as polyethylene, PVC, polypropylene, polystyrene, linear polyester, polycarbonate, polyamide, cellulose acetate and poly acid formaldehyde resin, etc.
With this molding technology, it can not only produce small volume bottles of several milliliters, but also can produce thousands of liters of large-volume barrels and storage water tanks, as well as floating balls, automobile fuel tanks and kayaks.
What characteristics should blow molding products have?
1.Environmental stress cracking resistance: as a container, it has the ability to prevent cracking when it comes into contact with surfactant;
2.Air tightness (permeability resistance) : refers to the characteristics that prevent the outward diffusion of oxygen, carbon dioxide, nitrogen and water vapor.
3.Shock resistance: in order to protect the goods in the container, the products should have impact resistance that cannot be broken down from one meter height.
4. In addition, there are drug resistance, static resistance, toughness and extrusion resistance.
What are the advantages of blow molding?
1.Hollow, double-walled structure can absorb and eliminate impact energy;
2.Flexible design, with high functionality and low production cost;
3.The processing technology can change the thickness of the embryo;
4.During processing, the thickness of the product can be changed at will without improvement of the mold;
5.Low pressure molding (the internal stress of the mold is much smaller than that of the injection molding), so as to improve dimensional stability, chemical corrosion resistance and high temperature performance;
6.Assembly diversity: self-tapping screw, die insert, rivet expansion fastener;
7.Simple mould, low cost and short processing cycle;
8.The sample mould with low price can be produced quickly.
After reading these, are you familiar with blow molding ?Tomorrow, Yankang will continue to share with you the things of the blow molding machine.Please look forward to it!