Pay attention to the viscosity of hydraulic oil when using hydraulic press?
One of the important indicators to test the performance of hydraulic oil is its viscosity. High-quality hydraulic oil can makefour-column hydraulic pressThe system is very stable in operation and has high efficiency, convenient and sensitive operation, and low power consumption. If the hydraulic oil does not meet the requirements, the temperature of the four-column hydraulic press will rise, and the components will be worn and cavitation will occur. For example, when the viscosity of the hydraulic oil is relatively thick, the flow resistance of the four-column hydraulic press will increase and the speed will slow down, this not only increases the power consumed but also causes losses due to wear.
If the pressure drop is strengthened on the pipelines and valves of the four-column hydraulic press, the efficiency of the hydraulic system will be reduced. At this time, the wear will become more severe, causing the oil temperature to gradually rise, thus causing leakage. However, if the viscosity of the hydraulic oil is relatively low, the leakage loss will be aggravated. If it is serious, the oil film between parts will be directly damaged, resulting in faster friction damage between various accessories.
Viscosity requirements and characteristics of hydraulic oil?
Hydraulic wrenches usually use 46 and 32 wear-resistant hydraulic oils. Hydraulic oil viscosity is an important indicator of hydraulic oil. Low viscosity will increase leakage and reduce volumetric efficiency; high viscosity will increase viscous friction loss and even cause cavitation or sticking. The following is a detailed explanation: the viscosity requirements and characteristics of hydraulic oil.
Viscosity requirements and characteristics of hydraulic oil:
1. Good viscosity-temperature performance
When the hydraulic system works, the oil temperature increases with the pressure loss. If the viscosity-temperature performance of the hydraulic oil is poor, the viscosity will be significantly reduced, resulting in poor lubrication and leakage, affecting the accuracy of work. If the hydraulic system starts in winter due to increased viscosity, it will affect the start. Therefore, within the working temperature range, the viscosity change range should be small. The hydraulic oil temperature index is generally above 90.
2. Good rust resistance
When the hydraulic equipment is parked or stored for a long time, the hydraulic components are easy to rust, and the hydraulic oil is required to have good anti-rust performance.
3. Good oxidation resistance
When the hydraulic system is working, with the gradual increase of the oil temperature, the oil is more and more easy to oxidize and deteriorate. Especially at high temperatures, the oxidation rate is very fast. Oil oxidation will produce sludge sediment, pollute the system, and even affect the normal operation of the system.
4. Good anti-emulsification
If the hydraulic oil is mixed with water, the substances with poor stability in the hydraulic oil will produce hydrophilic organic acids and soap, which will emulsify under the stirring of the pump, reduce the lubricity, and affect the working performance of the pump and the valve.
5. Good anti-foam performance.
If the hydraulic oil has foam, it will cause the hydraulic system to crawl and noise.
6. Good lubrication performance
The matching clearance of the moving parts of the hydraulic components is very small. Generally speaking, in order to improve the service life of components, it is necessary to form a high-strength oil film on the moving surface to form liquid lubrication and reduce wear.
7. freezing point
Requirements of hydraulic oil freezing point should be lower than the low ambient temperature 10C, otherwise the temperature is too low, the oil level rises, the impact of the start even does not work.
8, good compatibility
In order to avoid deterioration and failure, there should be little or no chemical interaction between the oil and the various materials.
The viscosity and precautions of hydraulic oil during the use of hydraulic press?
Viscosity is one of the important performance indicators of hydraulic oil. Whether it is reasonable or not has a significant impact on the smoothness of movement, reliability and sensitivity of the hydraulic machine plant system, system efficiency, power consumption, cavitation, temperature rise and wear. For example, when the hydraulic oil viscosity is high, it will increase the flow resistance of the hydraulic oil and slow down the flow speed; and due to friction loss, increase the power consumption of r; increase the pressure drop on the valve and pipeline, thereby reducing The efficiency of the system is also due to increased friction, which increases the oil temperature and causes leakage. If the hydraulic viscosity is low, it will inevitably aggravate the leakage loss, and the wear of the leading parts will be accelerated due to the rupture of the oil film between the moving parts.