The quality of a hydraulic system depends not only on the rationality of system design and the performance of system components, but also on the pollution prevention and treatment of the system. The pollution of the system directly affects the service life of the components that work in the hydraulic system. According to statistics, about 70% of hydraulic system failures at home and abroad are caused by pollution.
Oil contamination
1. The hazards of oil pollution to the system are mainly as follows:
1) Pollution and wear of components
Various pollutants in the oil cause various forms of wear on the components, and solid particles enter the clearance of the moving pair, causing cutting wear or fatigue wear on the surface of the parts. Solid particles in high-speed liquid flow cause erosion and wear on the surface of components. The water in the oil and the products of oil oxidation and deterioration have a corrosive effect on the components. In addition, air in the system's oil causes cavitation, leading to surface erosion and damage of components.
2) Component blockage and clamping failure
Solid particles block the gaps and openings of hydraulic valves, causing valve core blockage and clamping, affecting work performance, and even leading to serious accidents.
3) Accelerate the deterioration of oil performance
The water and air in the oil are the main conditions for oil oxidation due to their thermal energy, and the metal particles in the oil play an important catalytic role in the oxidation of the oil. In addition, the water and suspended bubbles in the oil significantly reduce the strength of the oil film between the moving pairs, resulting in a decrease in lubrication performance.
2. Types of pollutants
Pollutants are substances in hydraulic system oil that pose a threat to the system. They exist in different forms in the oil and can be classified into solid pollutants, liquid pollutants, and gaseous pollutants based on their physical form.
Solid pollutants can be divided into hard pollutants, including: diamond, cutting, silicon sand, dust, worn metals, and metal oxides; Soft pollutants include additives, water condensates, decomposition products and polymers of oil, as well as cotton fibers and fibers brought in during maintenance.
Liquid pollutants are usually cutting groove oil, water, coatings, chlorine and its halides that do not meet the system requirements. It is usually difficult for us to remove them, so when choosing hydraulic oil, we should choose hydraulic oil that meets the system standards to avoid unnecessary failures.
Gaseous pollutants are mainly air mixed into the system.
