How to take samples after hydraulic oil filter treatment?

Hydraulic oil filters are not uncommon in our applications. In order to better operate the filter, make it reach the best service life, and improve work efficiency, we often check the filter oil to further understand the normal state of the filter. Today, let's learn how to take samples to evaluate the performance of the filter.

After the new hydraulic oil is used, the color of the oil will change, the additives in the oil will also change, and the performance of the oil will be greatly reduced. Hydraulic oil filters are mainly used for the filtration, dehydration, decolorization, degassing and other treatments of waste oil, and restore the original performance of the oil. We need to analyze and test the physical, chemical and electrical properties of the oil to determine whether the filtered hydraulic oil can be used again and whether additives of certain components need to be added during use. Analyze the main component structure, component content and some trace substances in the oil.

Conventional analysis

1. Physical properties experiment. 

Since mineral oil is not a single chemical substance, but a mixture of multiple different liquid hydrocarbons. The monomer component cannot be determined, and the physical properties of the lubricating oil filter can only be understood as a combination of the properties of various hydrocarbons. Therefore, conditional experiments are generally used to determine the physical properties of the oil. 

That is, according to the conventional experimental conditions and processes, special experimental instruments are used for measurement. For example, the density, viscosity, flash point, freezing point, benzene point, etc. of oil products.

2. Chemical experiment. 

The principle of its determination is to use the characteristics of the relevant substances in the oil products to react with certain reagents to perform qualitative or quantitative analysis. For example, the determination of water-soluble acid or alkali, acid value, caustic soda experiment, oxidation stability, etc. of oil products.

3. Electrical performance experiment. 

As a liquid insulating medium, insulating oil reflects its electrical performance by measuring its breakdown voltage, dielectric loss factor, volume resistivity, gas precipitation, etc. The identification of the electrical properties of oil products also requires the use of special instruments and the determination according to the standardized experimental methods, which is also a conditional experiment.

Instrumental analysis

In recent years, the use of analyzers for oil quality measurement has developed rapidly. According to the measurement principle, it is mainly divided into electrochemical method, optical method and chromatography and other analysis methods. A brief introduction is as follows.

1. Electrochemical analysis method.

 The principle is to analyze based on the relationship between the concentration of the substance being measured and the potential, current, conductivity, capacitance or charge. For example, when measuring the moisture content in insulating oil, the coulometric method (coulometric titration method) can be selected.

2. Optical analysis method. 

Since light is part of the electromagnetic spectrum, it can be analyzed based on the interaction between the substance and the electromagnetic wave, or it can be analyzed using the optical function of the substance. If the infrared light harmonic method is selected, the content of aromatic hydrocarbons in the oil can be measured.

3. Chromatographic analysis method. 

The principle is to use the difference in absorption or solubility of each component in the substance being measured by the static high-boiling point liquid or solid adsorbent (stationary phase), as well as the difference in separation distribution coefficient, so that the components in the gas or liquid being measured are separated due to different absorption and forward movement speeds, and then enter the detector for identification. For example, gas chromatography is used to measure the content of combustible gases in oil products.

Regularly sampling, analyzing and testing the oil filter correctly can effectively monitor the condition of the oil filter machine and naturally improve the working efficiency. At the same time, it ensures the orderly progress of the work, so it is necessary to test the oil filter.