Hydraulic oil is the hydraulic medium used in the hydraulic system using liquid pressure energy, which plays the role of energy transmission, anti-wear, system lubrication, anti-corrosion, anti-rust and cooling in the hydraulic system.
Conventional testing items of hydraulic oil: color, kinematic viscosity 40 100, viscosity index, moisture, flash point, acid number, mechanical impurities, cleanliness (also known as granularity, pollution), copper corrosion, foam characteristics, demulsibility, liquid phase corrosion, pour point, air release value, sealing adaptability index, element analysis, grinding spot diameter, etc.
According to the national standard "GB11118".1-2011 Hydraulic Oil, the testing items of hydraulic oil are:
1. Color detection (test method: GB T6540, SD6540 petroleum product colorimeter used).
If the hydraulic oil becomes cloudy or dark, it may contain impurities and needs to be replaced in time.
2. Density detection at 20 o'clock (test method: GB T1884, the instrument used SH102 F Petroleum Product Density Tester).
3. 40 kinematic viscosity detection (test method: GB T265, instruments used SD265B, SD265D, SH112C
Single-cylinder, double-cylinder, fully automatic kinematic viscosity).
Hydraulic oil viscosity refers to a physical quantity of fluid flow resistance, which is one of the important indicators of hydraulic oil performance.
Fourth, the opening flash point detection (test method: GB T3536, the instrument used SH106 B open flash point tester).
5. Pour point detection (test method: GB T3535, the instrument used SH113B-Q, SH113C pour point tester).
For hydraulic fluids used in cold areas, it is necessary to have good low-temperature performance. The pour point is its main metric.
6. Acid value and alkali number detection (test method: GB T4945, the instrument used SH108A upgraded oleic acid number tester).
7. Cleanliness testing (test method: DL T432, the instrument used SH302A B portable automatic oil particle counter).
Contaminants in hydraulic fluids can accelerate the wear and oxidation of the system, further accelerating the degradation of the hydraulic fluid and causing damage to the system.
8. Moisture detection (test method: GB T260, instrument SD260SH103 A Petroleum Duplex Moisture Meter (Trace Moisture Meter).
High levels of moisture can cause deterioration of hydraulic fluids, making their rheology unstable, increasing the wear of hydraulic system pumps and reducing the life of the system.
9. Oxidation detection (test method: GB T12581, the instrument used SH12581 plus inhibitor mineral oil oxidation stability tester).
Oxidation is the main cause of oil degradation in hydraulic systems, so it is necessary to ensure the oxidation resistance of hydraulic oil.
10. Abrasion detection (test method: SH T0189, the instrument used SH120 four-ball machine).
Under the conditions of 392N, 75, 60min and 1200R, the anti-wear performance of the hydraulic oil directly affects the lubrication effect of the relevant components of the hydraulic system, and is an important quality index of anti-wear hydraulic oil.
Ten. 1. Anti-demulsification detection (test method: GB 7305, the instrument used is SH122 SD7305 petroleum product demulsification tester).
Ten. 2. Liquid phase corrosion (24H) (test method: GB T11143, the instrument used SH123 liquid phase corrosion tester).
Ten. 3. Copper sheet corrosion (1003 h) (test method: GB T5096, the instrument used SD5096 Petroleum Products Copper Sheet Corrosion Tester).
Ten. Fourth, foam tendency (test method: GB T12579, the instrument used SH126 B foam characteristics tester).
Hydraulic oil will be mixed with air during operation, which will reduce the efficiency of the system and even cause equipment damage, so hydraulic oil is required to have good anti-foaming performance.
Ten. 5. Air release value (test method: SH T0308, the instrument used SH0308B air release value tester).
Ten. 6. Sealing adaptability index (test method: SH T0305, the instrument used SH0305 seal adaptability tester).
Ten. 7. Oxidation stability (rotary oxygen bomb method) (test method: SH T0193, the instrument used SH0193C rotary oxygen bomb tester).
Ten. 8. Mechanical impurities (test method GB T511, instrument used: SH101B C automatic mechanical impurity tester).
Precipitates or colloidal suspended solids present in lubricating oils that are insoluble in solvents such as gasoline, ethanol and benzene. Most of these impurities are sand and iron filings, as well as some organometallic salts that are insoluble in solvents due to additives.