Form Analysis of Hydraulic System Leakage

The leakage of the hydraulic system is the phenomenon that the working medium flowing or temporarily stored in the hydraulic components and the system cavity flows from the high pressure cavity to the low pressure cavity or from the system to the outside of the system through the non-working channel. Leakage is a common phenomenon in metallurgical hydraulic equipment. Leakage may occur in all links from power components to actuators, which is determined by the nature of hydraulic transmission. However, once the leakage exceeds the allowable range, it becomes a leakage failure, which is not allowed and must be effectively controlled.

Hydraulic system leakage can be divided into fixed seal leakage and moving seal leakage according to the leakage location. Fixed seal leakage mainly includes leakage of the sealing surface of the valve and valve block, leakage at the connection of the oil cylinder port, leakage at the connection of the motor oil port, and leakage at the connection of the oil pump inlet and outlet; leakage of the moving seal mainly includes leakage of the pump spindle, motor Spindle leakage, extended valve stem leakage and hydraulic cylinder piston rod leakage, etc.

According to the form of oil leakage, it can be divided into internal leakage and external leakage. External leakage mainly refers to the leakage of hydraulic oil from the inside of the system to the external environment; internal leakage refers to the flow of hydraulic oil from the high pressure side to the low pressure side inside the system due to the existence of pressure differences between the high and low pressure sides of the system and the failure of seals. Among them, due to factors such as many internal leakage incentives, wide distribution of related components, and difficulty in direct monitoring, coupled with the fact that internal leakage is the main factor affecting the working efficiency of the hydraulic system, excessive internal leakage will cause fluctuations in the control accuracy and efficiency of the hydraulic system. The stability and reliability are reduced, and even the original design function is lost. Internal leakage has become the top priority of hydraulic system prevention and control.