How to buy a glass teapot?
1. The tightness of the lid should be appropriate:
When purchasing a glass jug, check the tightness of the lid and the neck. If the lid and the neck are too loose, it will easily fall off during use. And if it is absolutely consistent, it is also prone to jam, and it is easy to cause damage.
Therefore, the lid and the body of the glass teapot should maintain a certain degree of tightness, and the lid of the pot does not mean that it is inferior.
Furthermore, the glass tea set is not a pressure-resistant container that can withstand pressure. If the lid is too tight and too tight, the air portion will expand and contract when the internal temperature changes (whether it is natural cooling or open flame heating). If the air pressure difference cannot be balanced, the entire glassware becomes a pressure vessel, and if it exceeds the pressure load, an explosion will occur.
Although the lid of the pot cannot be completely closed and does not affect the normal use of the tea set, in order to satisfy the mentality that everyone does not care, the lid of the glass tea set on the market is a combination of a bamboo lid and a sealing ring, which is good select.
2. Pay attention to the small mouth of the cup or the bottom of the cup:
This embarrassing, called "glass drop" in the production of professional terms, is the finishing part of the manual glass products after the complete molding, cutting off the excess glass solution, is a feature of the glass before the manual furnace.
Leaving the mouth at the mouth of the cup or the mouth of the cup can prevent the absolute suction between the glass fittings, and avoid the situation that the high pressure in the pot cannot be released during the heating process. However, for the sake of beauty, there are also many handmade glass tea sets that intentionally leave the glass drops on the bottom of the cup.
This is a phenomenon unique to the glass tea set that has been used in the industry for hundreds of years. It is normal and exists on all hand-blown glassware. It is also an important feature that distinguishes manual glass from machine glassware.
3. Allow manual traces or small bubbles:
The high-quality glass tea set is made of pure material. If the material is not pure, the glass will produce ripples, bubbles and sand. Pattern, refers to the appearance of streaks on the surface of the glass; bubble, refers to the appearance of small holes in the glass; sand, refers to the glass contains white silica sand without melting. These flaws affect the expansion coefficient of the glass, which tends to cause cracking of the glass, and may even cause automatic cracking due to excessive temperature.
Of course, the number and size of bubbles is one of the manifestations of high quality, but the probability of producing “no any manual traces without any small bubbles” in a high-temperature processing environment is almost zero, and this is also the case with expensive heat-resistant tea sets. But as long as it does not affect the appearance and use, we should allow some inevitable manual traces and small bubbles to exist.