The double-wall glass cups are one of the most important series for Garbo glassware. The double-layer glass is made of high borosilicate glass, which has the characteristics of
high-temperature resistance, incomparable corrosion resistance compared with traditional glasses, no lead harmful to the human body, no odor absorption, good health, safety, and transparency, mainly for heat preservation and heat insulation. it's very popular.
But have you noticed that there is an air hole at the bottom of each double glass?
It turns out that double-layer glasses are generally blown by hand, and there is an air outlet at the outer bottom of the cup in order to discharge gas during the blowing process to prevent the cup from deforming and cracking. This process is similar to the inner tank of a thermos bottle, which is the closing point. Here the air between the glass can be excluded during the production process.
It can balance the pressure between the glass when loading hot water and cold drinks, so that the air circulation avoids the infiltration of water vapor, effectively prolongs the service life of the glass and ensures safe use. The main function is to promote air circulation in the cup and prevent the cup from breaking due to pressure.
To sum up, the air hole at the bottom of the double glass is designed because the role of the hole is that when the cup is filled with hot water and the air begins to expand, there will be a place to discharge the air, otherwise, the cup will burst due to excessive pressure. so that the user gets hurt.
In other words, the air hole at the bottom of the double glass is actually a protective device, which can ensure the safety of the glass to a great extent, so when using the double glass, we try not to touch the air hole at the bottom of the glass at will. Avoid causing damage to the stomata, it is not easy to repair.