Why is there a groove at the bottom of the PET beverage bottle?

Why is there a groove at the bottom of the PET beverage bottle?

Why is there a groove at the bottom of the PET beverage bottle?

Why is there a groove at the bottom of the PET beverage bottle?
We usually drink beverages, mineral water bottles, or yogurt cans have a bump on the bottom. Why?
We usually drink beverages, mineral water bottles, or yogurt cans have a bump on the bottom. Why?O1CN01Cw6Jcp2JmYthiCNJP_!!919739464.jpg

Is there a groove at the bottom? Mainly it is easy to lay flat and also to increase the volume and strengthen the bottom

  1. Flattening: After the bottom is recessed, only a circle at the bottom of the bottle can touch the ground, so you may feel that the bottle is easy to fall. In fact, the opposite is true! If the bottom of the bottle is recessed, only one circle touches the ground, so as long as the circle is flat Then the bottle will not shake. Sometimes the bottom of the blow-molded bottle should be protruding (higher than the bottom outer ring) due to multiple reasons. This way the bottle will not be flat.


  2. Increase the volume: The bottom of the bottle with the same appearance is flat and the other is recessed, so there must be a lot of things in the flat-bottomed bottle. The manufacturer uses the opposite principle to recess the bottom so that the bottle can be made slightly larger But in fact, the things inside are the same. In this way, it may be better to attract buyers (the mentality of taking advantage of the small bargain)


  3. Reinforcement: There is a groove at the bottom of the bottle to reinforce the bottom of the bottle, just like the Wahaha bottle. In fact, the bottle is very thin and easy to pinch into the recess, so many lines are made on the bottle body, which seems to be used for decoration. In fact, it is used for reinforcement. My factory makes bottles, so my answers will not be completely right, but they will not be wrong.1612700726197-eff254dcf0bc4f509418164fb6b622a3-800x533.jpg

  4. Subjectively, it is to pack the insufficient product capacity, so that people can not see that there is not much visual reality; objectively, it increases the stability or beauty of the bottle holder, and makes people ignore the manufacturer's consciousness of ignoring customers.


This is also determined by the production of plastic bottles. Beverage bottles are manufactured using a technology called vacuum negative pressure during the production process. Because the air pressure enters from the direction where the bottle is threaded (that is, the position of the beverage bottle mouth), it is airtight. The plastic bottle is heated in the mold to a temperature that can be deformed, and the pressure pushes the softened plastic to the bottom, which is shaped according to the shape of the inner wall of the mold, so a thicker plastic will be formed at the bottom of the plastic bottle. In order to make the thickness of the plastic bottle uniform, a concave shape is designed at the bottom of the mold. It also increases stability to a certain extent.


As a person in the beverage bottle industry, I just want to say that those who say that the bottom groove is for visual effects and cover up the lack of product capacity are pure nonsense! We do plastic molds, focusing on preforms, bottle caps, and blowing molds. . When each customer opens the bottle mold and accepts it, the first inspection is the capacity, followed by the mold-closing line, the finish and so on. If the capacity is not up to the requirements, the others will be useless. Of course, before the mold is opened, when drawing the product, he will ask the customer, for example, does the 500ml capacity he requested go to the bottle mouth or the neck? In order to save costs and save some material costs, some small company customers will choose to fill the bottle mouth, while some customers will choose to fill the neck or below the neck. It seems that the manufacturer has not filled it. In fact, the capacity is enough, but the bottle The designed capacity is greater than the actual capacity. Others are not evaluated, after all, they are not technicians, but business.
ee99.jpgThere is another reason. At the bottom center of each bottle, there is an obvious dot. That is the feed port when the preform is injected. The high-grade air-sealed mold is injected. The feed port is very small. When it comes out, it is relatively large, but no matter the size, there will be more or less protrusions. If the bottom of the bottle is flat, then the feeding port will affect the stability of the bottle, and it may even be impossible to place it.

Professional blow molding machine manufacturer