It's so cold, you should not change your antifreeze?
Soon in midwinter, the change of antifreeze. Let's talk about automobile antifreeze. Antifreeze from the composition consists of ethylene glycol antifreeze, glycerin type antifreeze antifreeze, alcohol. At present, the mainstream is usually ethylene glycol antifreeze. Ethylene glycol antifreeze glycol is a colorless, odorless slightly sticky liquid, the boiling point of 197. - 4 ℃, freezing point 11. 5 ℃, it can mix with water at any proportion. After mixing due to changed the vapor pressure of cooling water, significantly reduce the freezing point. The lower level within a certain range decline with the increase of the content of ethylene glycol. When the content of ethylene glycol was 68%, freezing point can be reduced to - 68 ℃, exceeds this limit, freezing point rise instead. Different ratio of the mixture of ethylene glycol and water content of antifreeze solidifying point is different also, 60% of the mixture of ethylene glycol and 40% of soft water, antifreeze, solidifying point to - 55℃；
And when the ethylene glycol in antifreeze and water 50%, anti-freezing temperature for - 32℃。 Features: 1, acid glycol antifreeze in the use of easy generation, have corrosion effect on metals. Therefore, ethylene glycol type antifreeze usually add right amount of disodium hydrogen phosphate and so on to prevent corrosion. 2, ethylene glycol is toxic, but because of its high boiling point, won't produce steam and thus will not be inhaled and cause poisoning in the body. 3, ethylene glycol, water imbibition is strong, storage containers should be sealed, after to prevent water overflow. 4, due to the boiling point of water is lower than ethylene glycol, used by evaporation is water, when a lack of coolant, just add water. This kind of antifreeze used after recycling ( Prevent mixed with oil products) , after precipitation, filtration, adjust the concentration of water, add preservatives, still can continue to use, generally available 3 & ndash; For five years. The boiling point of ethanol type antifreeze is 78. 3 ℃, freezing point is - 114℃。
Wine is mixed with water can be arbitrary proportion, composition of different freezing point of antifreeze. The more the content of alcohol, the lower the freezing point. Alcohol is flammable, when the alcohol content of 40% or more in antifreeze, is easy to produce ethanol vapor and catch fire. Therefore, fangdongye shoulds not be more than 40% of alcohol content, freezing point will be limited to - Around 30 ℃. Alcohol and water mixture of antifreeze has good liquidity, heat quickly, conveniently, simple preparation, etc. Features: alcohol is flammable, low boiling point and evaporation loss. Alcohol evaporates, antifreeze component changes, freezing point. In the mountains, the plateau area of antifreeze, unfavorable use alcohol because alcohol evaporation loss. General area traffic should be tested periodically alcohol content, timely added. Glycerin type antifreeze glycerol is also called the glycerin, glycerine antifreeze, nonvolatile and fire, the metal corrosion resistance is small, but the glycerin reduce the freezing point of low efficiency, make the same freezing point of antifreeze, is larger than the amount of ethylene glycol, alcohol, and high cost. As a result, the domestic antifreeze used less, and abroad because of environmental requirements higher, so the United States national standard antifreeze for glycerine antifreeze. How long does it take to replace a antifreeze? 1, most of the family cars are changing once every two years or forty thousand kilometers. If transport intensity big, can change in advance. 2, within the time limit is not to replace the antifreeze coolant, if found antifreeze coolant is less than the minimum scale value ( Antifreeze coolant normal capacity should be between MIN and MAX) , will increase in time, or it will affect the engine cooling efficiency.