What is a vacuum flask glass refill&thermos flask

The vacuum flask consists of two flasks, placed one within the other and joined at the neck. The gap between the two flasks is partially evacuated of air, creating a near-vacuum which prevents heat transfer by conduction or convection. Heat transfer by thermal radiation may be minimized by silvering flask surfaces facing the gap but can become problematic if the flask's contents or surroundings are very hot; hence vacuum flasks usually hold contents below the boiling point of water. Most heat transfer occurs through the neck and opening of the flask, where there is no vacuum. Vacuum flasks are usually made of metal, borosilicate glass, foam or plastic and have their opening stoppered with cork or polyethylene plastic. Vacuum flasks are often used as insulated shipping containers.

How to test insulation quality of the vacuum flask?

• Check the inside (that is, the suction mouth) is intact, if there is a break between layers is damaged inside the vacuum, lost heat preservation ability.

• Look inside presence of blowout trace.

• See if bottle is round. If you don't round bottle, bottle stopper can't seal, will reduce the heat preservation ability.

•Fill it with boiling water and cap it.

•Measure its temperature with a thermometer every hour or two and see what the temperature graph looks like

Directions for use

1, the cork don't fit too tight.
2, pour cold water into hot water before the bottle net.
3, thermos bottom cushion pad tight at any time, to avoid loose inside so as to avoid damage.
4, when the hot water to avoid pumping metal shell on the bottle mouth, lest cause broken inside.
5, when used to avoid violent vibration, carefully protect highlight the tails, so as not to lose heat preservation performance.
6, bottle inner product have scale, can pour into acetic acid or hot yellow vinegar, rice vinegar to dissolve slowly, don't use hard material such as shock washing sliders.