Mechanical impurities are substances polluted by the outside world, mainly oil sludge, silt, dust, rust, metal scraps, fiber, etc. These got mixed in the process of storage, transportation, storage and use.
These impurities can easily clog the filter and pipe if mixed in the oil, which will cause the oil supply to be abnormal. And entering equipment will cause mechanical wear.
Therefore, special attention should be paid to cleanliness in the storage and transportation. This is why it is best to filter first when used.
In general, the mechanical impurities of lube base oil are controlled at less than 0.005% (less than 0.005% is considered No). But for some oils, with a large additive dosage, the mechanical impurities are slightly bigger.
The reason is that, after adding a variety of additives, there may be some solvents insoluble. These colloidal metal organics do not affect their use effect.
Therefore, it is not easy to judge the quality of oil products by the size of mechanical impurities, should analyze the properties and categories of the impurities also.
By Gage Zhou
The author is Overseas Manager to Richful Lubricant Additives.