According to statistics, most of the failures of hydraulic fittings are related to hydraulic oil, and the failures of hydraulic oil are almost caused by impurities.
The inspection content of hydraulic oil mainly includes the following points: cleanliness, color, viscosity and consistency of hydraulic oil, as well as odor. When the hydraulic oil flows from the high pressure side to the low pressure side without mechanical work, heat will be generated in the hydraulic system. If the temperature of hydraulic oil is too high, the very expensive seals will deteriorate and the oil will be oxidized to failure, which will cause corrosion and sediment formation, and even block the damping hole and the wear of acceleration valve. If the temperature is too high, the valve and pump will be stuck, and the high temperature of hydraulic fittings will also bring safety problems. With the help of the inspection of the oil temperature in the oil tank, sometimes the system fault can be eliminated before serious harm occurs.
In most systems, the relief valve is the main source of heat, the pressure relief valve of hydraulic fittings through the flow is too large is another main cause of heat. As the low efficiency is related to energy loss, it is necessary to check the working temperature to know whether there is a problem of low efficiency. For the hydraulic system, the control of pollutants in the oil is a main work. The sources of pollutants in the hydraulic fittings mainly include the following aspects:
1. With new oil.
2. Inside the system during assembly.
3. Enter with the surrounding air.
4. Internal wear of hydraulic components.
5. Entered through a leaking or damaged seal.
6. Brought in during maintenance.