1, precipitation and drainage methods:

This method takes advantage of the different specific gravity of water and oil, and water will precipitate at the bottom of oil. Water with an open bottom can be discharged through the drain valve. But this method can't completely drain the water in the oil. If the state of water is emulsified, natural precipitation cannot separate oil from water; There is always more than 100-500ppm water in hydraulic oil, which will also cause harm to hydraulic system.

2, oil replacement method:

When it is found that hydraulic oil enters the water, first release the hydraulic oil in the oil tank, add new oil (the new oil quantity can meet the minimum oil level of oil pump circulation), start the oil pump, and operate each hydraulic system.

Clean and replace the hydraulic pipeline and hydraulic device, and the emulsified residual hydraulic oil polluted by water will flow back to the oil tank, drain the oil in the oil tank again, add new oil again, and repeat the above process until the hydraulic oil in the oil tank is transparent.

The disadvantages of this method are: the amount of oil needed for oil change is large, and how to deal with the oil-water mixture after replacement, if the purpose of secondary utilization cannot be achieved, the cost is too high.

3. Circulating filtration method of vacuum oil filter

When there is water in the hydraulic oil system, the circulating filtration method of the vacuum oil filter can not only separate emulsified water and free water from the oil; Even impurities can be filtered out together.

This method is the most widely used and effective filtering method at present. Because the vacuum oil filter is filtered in a purely physical way, it will not cause oil damage and the amount of oil after filtering will not be reduced. The quality of filtered hydraulic oil completely meets the industry standard. Its cleanliness and micro-water content even exceed the new oil standard.

Extended data:

Harm of mixing hydraulic oil with water;

1. When a certain amount of water is added to the oil, the hydraulic oil will be emulsified into a turbid state. If the anti-emulsification ability of hydraulic oil itself is poor, after a period of standing, water cannot be separated from the oil, so that the oil is always in a turbid state.

When this white emulsified oil enters the hydraulic system, it will not only rust the hydraulic components, but also reduce their lubrication performance, aggravate the wear of parts and reduce the efficiency of the system.

2. After the ferrous metal in the hydraulic system rusts, the peeling rust will flow and spread in the pipelines and hydraulic components of the hydraulic system, which will lead to the internal rust of the whole system and produce more peeling rust and oxides.

3. Water will also react with some additives in the engine oil, producing pollutants such as precipitation and colloid, which will accelerate the deterioration of the engine oil.

4. Water reacts with sulfur and chlorine in oil to produce sulfuric acid and hydrochloric acid, which aggravates the wear of parts, accelerates the oxidation and deterioration of oil, and even produces a lot of sludge.

5. These water pollutants and oxidation products immediately become catalysts for further oxidation, which eventually lead to the blockage or seizure of hydraulic components, resulting in a series of failures such as hydraulic system failure, oil distribution pipe blockage, cooler efficiency reduction, oil filter blockage and so on.