The function of the hydraulic system is to increase the force by altering 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 transmission systems and hydraulic control systems. The hydraulic transmission system primarily functions to transfer power and motion. The hydraulic control system is designed to ensure that the output of the hydraulic system meets specific performance requirements (especially dynamic performance), with the so-called hydraulic system generally referring to the hydraulic transmission system.
Maintenance:
The quality of a hydraulic system depends not only on the rationality of the system design and the performance of the system components, but also on the system's protection against and treatment of contamination. System contamination directly affects the reliability of the hydraulic system's operation and the lifespan of the components. Statistics show that approximately 70% of hydraulic system failures worldwide are caused by contamination.
Fault Diagnosis:
Hydraulic drive systems are gaining increasingly widespread application 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 instability of raw and auxiliary components in terms of quality, as well as improper use and maintenance. Since the system's components and working fluids operate within a closed oil circuit, which is not as直观 as mechanical equipment or as easily measured with various testing instruments like electrical equipment, hydraulic systems rely on a limited number of pressure gauges and flowmeters to indicate certain parameters. Other parameters are difficult to measure, and the root causes of general malfunctions can be of many kinds, posing difficulties for diagnosing hydraulic system issues.
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 on repair time and costs. Using simple technical methods, they should pinpoint the fault location and cause as quickly as possible and carry out repairs, restoring the system to normal operation and striving to prevent similar faults from recurring in the future.
System Maintenance:
A system typically undergoes flushing before being officially put into operation. The purpose of flushing is to remove pollutants, metal shavings, fiber compounds, iron cores, and other contaminants within the system. In the first 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 oil lines:
1) Clean the oil tank with a quick-drying solvent, then remove any residue with filtered air.
2) Clean all piping in the system; in some cases, it is 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 flushing plate on the collector 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 system utilizes electro-hydraulic servo valves, I might as well add a few points. The flushing plate of the servo valve must allow oil to flow from the supply line to the collector and then back into the oil tank. This enables the oil to circulate repeatedly, cleaning the system and allowing the oil filter to remove solid particles. During the flushing process, check the oil filter every 1 to 2 hours to prevent clogging by contaminants. Do not open the bypass at this time. If the oil filter begins to clog, change it immediately.
The cycle for flushing is determined by the system's construction and the degree of system contamination. If the sample of the filter medium shows little to no foreign contaminants, install a new oil filter, remove the flushing plate, and install the valve to operate!
Scheduled Maintenance: Establish a regular maintenance system for the hydraulic system
