Do you understand the principle of shape design for plastic beverage bottles?

Iced bottled drinks are a great way to relieve the heat in summer. These drinks are so popular on the market, partly because the drinks themselves taste sour, sweet, and refreshing, and partly because the packaging bottle is appropriate in size and convenient to carry. Most beverage packaging bottles are made of plastic material and have similar shapes. The shape design of plastic bottles is the result of considering their functions, economic benefits, aesthetic appearance, and other aspects.
Upon careful observation of the appearance of plastic beverage bottles, it is not difficult to find that their upper, middle, and bottom shapes are different. The upper part of the bottle body is similar to a dome shape, some even have very regular cones, and the top bottle mouth is cylindrical; The middle of the bottle body is similar to a cylindrical shape, and in order to enhance its aesthetics, some circular, vertical arches or various convex and concave shapes are added; The bottom of the bottle body is generally designed to be concave and has a petal like structure similar to a dome. The main consideration of these designs is to enhance the bottle's load-bearing capacity.
The packaging bottles of such drinks must have high compressive strength to prevent deformation of the bottle body. Mechanically speaking, arches can withstand significant external forces. The force point of a plastic bottle under pressure will transmit the force to adjacent areas, and the external force will be distributed along the surface of the bottle body, causing each part of the arch to share a portion of the force. In addition, many bridge structures adopt arch design to achieve safety and stability. Take the center point of the arch foot line of the arch shape and connect it with the arch crown as the axis for rotation. The arch shape rotates one cycle to form a dome. So, the dome shape on the top of a plastic beverage bottle can be seen as a combination of several arches, which can withstand external pressure without generating external forces.
The middle of the bottle body is the thinnest part of the entire packaging bottle, which is prone to dents when subjected to external forces. If the middle of the cylindrical bottle body is split from the middle, it can be separated into two arched structures. Although it is an arched structure, it cannot completely avoid the drawbacks caused by the material being too thin. So, in order to improve the compressive strength of the middle part, various concave and convex patterns can be added to the surface of the bottle body, such as circular, serrated, finger shaped, and rigid edges, without increasing the wall thickness. This not only improves the compressive strength of the bottle body, but also enhances the aesthetic appearance.
The bottom of the bottle not only supports the entire packaging bottle, but also frequently comes into contact with external objects, requiring higher structural strength. Some carbonated beverages contain a large amount of gas, and there is a certain amount of pressure inside the packaging bottle, especially after shaking or temperature rise, the carbonated gas is released, and the internal pressure will increase. When the capacity of the packaging bottle is large or the beverage contains bubbles, the risk of bottle breakage is greater. The concave shape of the bottle bottom allows the packaging bottle to maintain a stable vertical standing state, effectively reducing the risk of scratching the bottle bottom, and also endowing it with strength against internal pressure and water pressure impact, preventing the bottle bottom from cracking. In theory, the most rupture resistant structure is the round bottle bottom design, but it needs to be paired with a base that can make the bottle stand upright and stable. The petal shaped bottle bottom does not require an additional base, and multiple supports ensure the stability of the packaging bottle when standing. Moreover, this petal shaped design is more aesthetically pleasing.
When designing containers, capacity is also an important consideration. Under the same material usage, the spherical design structure has the largest capacity, but if used on beverage packaging bottles, the standing stability is insufficient and the market practicality is not enough. The cylindrical shape ensures both capacity and standing stability, and is easy to blow, making it easier to fill and transport, which is more in line with market demand.