Today I will tell you how the bottle blowing machine developed. In history, Enoch ferngren and William kopitke were the first to verify the blow molding process. The principle of this process comes from the blowing of glass products. In 1938, ferngren and kopitke built a bottle blowing machine and sold it to Hartford empire. 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, more and more plastic products are produced by blow molding process. In the soft drink industry in the United States, the number of plastic containers has increased from zero in 1977 to 10 billion in 1999.
Blow molding process was used to produce low density polyethylene vials during World War II. In the late 1950s, with the birth of high-density polyethylene and the development of blow molding machine, blow molding technology has been widely used. The volume of hollow containers can reach thousands of liters, and some production has been controlled by computers. The plastics suitable for blow molding include polyethylene, polyvinyl chloride, polypropylene, polyester, etc. the obtained hollow containers are widely used as industrial packaging containers.
According to the parison making method, blow molding can be divided into extrusion blow molding and injection blow molding. The newly developed ones are multi-layer blow molding and stretch blow molding.
The extrusion process is to extrude the plasticized plastic into the extrusion and blowing die head through the screw, and then cooperate with the following die and compressed gas to realize the molding of the product.
The extrusion blow molding process of bottle blowing machine consists of 5 steps:
1. Make the plasticized raw material into plastic embryo;
2. Cut off part of the mold embryo and cut off the mold embryo through the closing of the mold;
3. Fill the mold cavity with gas to form the mold embryo and cool it;
4. Open the mold and take out the formed container;
5. Trim the flash to get the finished product.