Today, I will tell you how the bottle blowing machine w […]
Today, I will tell you how the bottle blowing machine was developed. Enoch Ferngren and William Kopitke first verified the blow molding process in history. The principle of this process is derived from glass blowing. In 1938, Ferngren and Kopitke built a blow molding machine and sold it to the Hartford Empire Company.
This is the beginning of the commercial blow molding process. In the 1840s, the variety and quantity of plastic products were very limited. Therefore, the blow molding process did not develop rapidly until very late. With the increase of product types and productivity, soon more and more plastic products are made by blow molding process. In the US soft drink industry, the number of plastic containers has grown from zero in 1977 to 10 billion in 1999.
The blow molding process was used to produce low-density polyethylene vials during the Second World War. In the late 1950s, with the birth of high-density polyethylene and the development of blow molding machines, blow molding technology has been widely used. The volume of the hollow container can reach thousands of liters, and some production has adopted computer control. Plastics suitable for blow molding include polyethylene, polyvinyl chloride, polypropylene, polyester, etc. The resulting hollow containers are widely used as industrial packaging containers.
According to the manufacturing method of the parison, blow molding can be divided into extrusion blow molding and injection blow molding, and the newly developed multi-layer blow molding and stretch blow molding.
The extrusion process is to extrude the plasticized plastic into the extrusion blow die head through a screw, and then cooperate with the lower mold and compressed gas to realize the product molding.
The extrusion blow molding process of the blow molding machine consists of 5 steps:
1. The plasticized raw materials are made into plastic preforms;
2. Intercept part of the parison and cut off the parison by closing the mold;
3. Fill the mold cavity with gas to shape the parison and cool it down;
4. Open the mold and take out the molded container;
5. Trim the flash to get the finished product.