The function of the hydraulic system is to increase the force by changing pressure. A complete hydraulic system consists of five components: power elements, actuating elements, control elements, auxiliary elements (accessories), and hydraulic oil. Hydraulic systems can be divided into two categories: hydraulic drive systems and hydraulic control systems. The primary function of a hydraulic drive system is to transmit power and motion. Hydraulic control systems are designed to meet specific performance requirements (especially dynamic performance) of the hydraulic system. The term "hydraulic system" commonly refers to the hydraulic drive system.
Maintenance:
The quality of a hydraulic system depends not only on the rationality of the system design and the performance of its components, but also on the system's protection against and treatment of contamination. System contamination directly impacts the reliability of the hydraulic system's operation and the lifespan of its components. Statistics show that approximately 70% of hydraulic system failures worldwide are caused by contamination.
Fault Diagnosis:
Hydraulic transmission systems have gained increasingly widespread applications across various fields due to their unique advantages, such as broad process adaptability, excellent control performance, and cost-effectiveness. However, their diagnosis can be challenging due to the inherent instability of components and accessories, improper use and maintenance, and the fact that system components and working fluids operate within sealed oil circuits. Unlike mechanical or electrical equipment, hydraulic systems lack direct visibility and cannot easily utilize various measuring instruments to assess parameters. Relying on only a limited number of pressure gauges and flowmeters to indicate system parameters at certain locations, other parameters are difficult to measure. Moreover, the root cause of general malfunctions can have numerous possibilities, adding complexity to hydraulic system diagnostics.
On the production site, due to constraints from production schedules and technical conditions, it is required that fault diagnosis personnel accurately and simply identify hydraulic equipment malfunctions; maintenance staff should utilize existing information and on-site technical conditions to minimize disassembly work, saving repair time and costs. Using simple technical methods, they should accurately locate the fault and its cause in the shortest possible time, and repair it, restoring the system to normal operation and striving to prevent the recurrence of similar faults in the future.
System Maintenance:
A system typically undergoes flushing before being officially put into use. The purpose of flushing is to remove pollutants, metal shavings, fiber compounds, iron cores, and other debris from within the system. During the initial two hours of operation, even without completely damaging the system, it can cause a series of malfunctions. Therefore, the following steps should be followed to clean the system's oil circuit:
1) Clean the oil tank with a quick-drying solvent, then remove the residue with filtered air.
2) Clean all piping in the system; in some cases, it may be necessary to soak the piping and joints.
3) Install oil filters in the pipeline to protect the valve's fuel and pressure lines.
4) Install a flush plate on the manifold instead of a precision valve, such as an electro-hydraulic servo valve.
5) Verify all pipeline sizes are appropriate and connections are correct.
If the electro-hydraulic servo valve is used in the system, let me elaborate a bit further. The flush plate of the servo valve must allow the oil to flow from the supply line to the collector and directly back to the oil tank, enabling continuous circulation for system flushing. This allows the oil filter to remove solid particles. During the flushing process, inspect the oil filter every 1 to 2 hours to prevent clogging due to contaminants. Do not open the bypass at this time. If you notice the oil filter beginning to clog, change it immediately.
The flushing cycle is determined by the system's construction and the degree of system contamination. If the filter medium sample has little to no external contaminants, install a new oil filter, remove the flushing plate, and install the valve for operation!
Scheduled Maintenance: Establish a regular maintenance system for the hydraulic system
