How many a bottle of beer?
There are two main requirements for bottle caps:1. tightness2. bite degreeThis means that the number of pleats in each bottle cap is proportional to the contact area of the bottle mouth, and the wave sealing at the outside of the bottle cap can increase the friction force and facilitate the opening. 21 teeth is the best compromise between these two requirements.
Why is the 21, is actually associated with the bottle opener, open bottles of beer is also a subject, to emphasize the safety and convenience, because beer contains large amounts of carbon dioxide, so the opening should be particularly careful, if the inside pressure or uneven easy to get hurt, especially violent shaking off beer, open the bottle very easy to burst. So how to open a beer bottle safely and conveniently should be considered in the design process. At that time, designers were able to find the easiest way to open the bottle quickly, so it was easiest and safe to open the 21 sawtooth teeth by constantly changing the sawtooth. So today's 21 jagged caps are formed. But because of this design are recognized, so quickly in some other beverage packaging applications, such as glass bottles of Coca Cola and Sprite bottle, are also used in this standard.
The 21 teeth of the beer cap are now made in accordance with the internationally accepted German standard DIN6099. This standard not only defines the diameter of the bottleneck, but also the shape of the edge of the bottle cap and the manufacturing material.
