Red liquid thermometer glass rod do you understand? Divided into several?

Speak of a thermometer, we see in life market, it is a kind of filling the red liquid thermometer, the thermometer is often used in industry and life, like mercury thermometer, it is to belong to a kind of expansion type glass thermometer. The red liquid thermometer according to the filling medium is mainly can be divided into two kinds: the first is a thermometer, alcohol is made by using the properties of heat bilges cold shrink alcohol thermometer. Under a standard atmospheric pressure, alcohol thermometer can measure the highest temperature is 78 ℃ commonly. Because alcohol under a standard atmospheric pressure, the boiling point is 78 ℃. But the pressure within the thermometer is generally higher than 1 standard atmosphere, so there are some alcohol thermometer range greater than 78 degrees. In the north cold season often use alcohol thermometer to measure temperature, condensation point is - this is because the mercury 39 ℃, in cold areas may be because the temperature is too low and make the mercury solidification, unable to normal temperature measurement. And the freezing point of alcohol is - 114 ℃, don't have to worry about this problem. The second is kerosene thermometer work substance is kerosene, its boiling point is generally higher than 150 ℃, below the freezing point 30℃。 So a measure of the kerosene thermometer range is about - 30℃~150℃。 Because of the boiling point of alcohol is 78 ℃, freezing point is - 117 ℃, the alcohol thermometer can lower than kerosene thermometer measured temperature, but it cannot determine the above 78 ℃ temperature. Currently on the market to sell more household temperature meter for kerosene thermometer. Its degree value is bigger, more is 1 ℃, so not able to do precise measurement. The most main red liquid thermometer is both temperature medium, red liquid thermometer use is very broad, our indoor and outdoor temperature, industrial production, life daily life can see the figure of it, through the introduction of small make up, whether you for this two kinds of alcohol thermometer thermometer features of each are not identical, if you want to when the choose and buy, be sure to remember according to need and the features of the thermometer to buy.