The relative molecular energy of water is much smaller than the relative molecular energy of oil, and the volume surges after gasification, which increases the pressure drop of the system and the power consumption increases accordingly, so the high content in oil will make the operation of the device fluctuate and cause the flushing tower. Moreover, the inorganic salts (Call2, MgCl2) brought in by the water content will also aggravate the corrosion of the device. The water content in light fuel oil will make the freezing point and crystallization point rise, resulting in the oil low-temperature water mobility becomes poor, causing the oil to analyze the ice particles at low temperature and block the filter and oil circuit, especially the water content in aviation coal and diesel oil will cause the interruption of oil supply, resulting in serious accidents. Water in lubricating oil will destroy lubricating film, make lubrication can not be carried out normally and increase the wear of machine parts. The inorganic salt brought in by water will also increase the corrosiveness of the lubricating oil and intensify the corrosion of the machine parts. When using lubricating oil containing water to work in a high temperature environment, the vaporization of water will destroy the lubricating film. The excessive water content in the raw material oil for regrinding will poison the catalyst, because the excessive water in the oil occupies the acidic center of the catalyst and destroys the balance of the metal center of the acidic center, so that the activity of the catalyst decreases or even deactivates, which affects the service life of the catalyst. Therefore, moisture content is a quality indicator in various oil standards.
        Measuring the moisture in oil provides an accurate measurement of the quantity of oil, i.e., the actual quantity of oil in the entire container can be known by subtracting the amount of water after checking the scale. Measure the water in the oil, according to the amount of its content, can determine the method of dehydration, in order to prevent the following hazards: such as the water in the petroleum products to absorb heat when evaporating, will make the heat of generation lower; light oil in the water will make the combustion process deteriorate, and can bring dissolved salt into the cylinder, generate carbon, increase the wear of the cylinder; in low temperature, the water in the fuel will freeze, blocking the fuel duct and In low temperature, the water in the fuel will freeze, blocking the fuel duct and filter, obstructing the fuel supply of the generator fuel system; the water in the petroleum product will accelerate the oxidation of the oil to produce rubber; the water in the lubricating oil will not only cause the corrosion of the engine parts, but also the water and the metal parts above 100℃ will turn into water vapor when contacting, destroying the lubricating oil film. Light oil products have small density and small viscosity, so oil and water can be easily separated. And heavy oil is the opposite, not easy to separate. The crude oil entering the normal reduced pressure distillation device requires the water content to be no more than 0.2%~0.5%; the specification standard of finished oil requires gasoline and kerosene to contain no water, and the water content of light diesel oil to be no more than traces; the water content of heavy diesel oil to be no more than 0.5%~1.5%; all kinds of lubricating oil and fuel oil have the corresponding control index