Views: 0 Author: Site Editor Publish Time: 2022-04-22 Origin: Site
If we look closely at our home kitchens and bathrooms, and medicine cabinets, count the types and quantities of plastic bottles: 20? 30 kinds? It is very likely that the packaging of detergent, toilet cleaning liquid, etc. are all in this ranks.
All hollow plastic products are made by blow molding, because the mouth is small and the mouth is big, it cannot be completed by injection molding. Simply put, there are four ways to blow plastic products conventionally: extrusion blowing, injection blowing, PET bottle blowing and one-step injection stretch blowing. According to the plastic material of the bottle and different application scenarios, customers choose different types of machines to carry out production. I'll start with a picture of the bottle to illustrate the machine-made difference:
1. PET mineral water bottle;
2. PE oil drum bottle;
3. PE medicine bottle;
4. PP baby bottle
The significant advantage of PET is its high transparency, which is suitable for packaging consumable food such as mineral water and edible oil. Another notable feature of PET material is high hardness and high fluidity, so it is not suitable for extrusion blowing technology. At present, the most commonly used method in the world is a two-step method: injection molding the tube blank, and then heating the tube blank with a PET bottle blowing machine to blow out the PET bottle that meets the requirements. The PET blow molding machine is only suitable for producing PET bottles, single layer.
The notable features of PE are moderate melting point, easy plasticization and moderate fluidity. Therefore, PE raw materials are widely used in hollow blow molding equipment. The significant advantages of hollow blow molding are: multi-layer co-extrusion, so food packaging needs anti-oxidation, pesticide packaging needs anti-penetration, cosmetic packaging needs to beautify the surface of the bottle, irregular hollow products, etc. Can use hollow extrusion blow molding machine to complete the production. At present, the largest blow molding machine in China can produce 100,000L buckets.
PE medicine bottle, because it requires surface smoothness, PE injection blowing is more suitable: first injection molding and then blowing on the same machine. There are three main limitations of injection molding technology: 1. It can only produce bottles under 1L, and it is relatively difficult to blow horizontally when it exceeds 1L; 2. It is impossible to produce different products and intelligently produce completely regular round bottles; 3. It is not possible to use regrind or barrier layers for co-extrusion.
PP baby bottle: Because it is a baby product, the surface requirements must be the highest. The injection stretch blowing equipment can meet the production and production of baby bottles: three-step production is realized on the same machine: first injection, then heating and pulling, then blowing, and finally automatically leaving the machine station.
The common features of the four types of equipment are blowing steps and molds, so the common auxiliary machines are: compressor, chiller... application scenarios.