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 drive systems and hydraulic control systems. The hydraulic drive system primarily functions to transmit power and motion. The hydraulic control system aims to ensure that the output of the hydraulic system meets specific performance requirements (especially dynamic performance). When we refer to the hydraulic system, it generally 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 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 applications across various fields due to their unique advantages, such as broad process adaptability, excellent control performance, and low cost. However, due to the unstable quality of components and accessories objectively, as well as improper use and maintenance subjectively, and since the components and working fluids in the system operate within a closed oil circuit, unlike mechanical equipment which is more直观 or electrical equipment that can be conveniently measured with various testing instruments, the hydraulic systems rely solely on a limited number of pressure gauges, flowmeters, etc. to indicate the working parameters of certain parts of the system. Other parameters are difficult to measure, and the root causes of general malfunctions are often numerous possibilities, which presents certain difficulties in diagnosing hydraulic system failures.

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 failures. It is also required that maintenance personnel, utilizing existing information and on-site technical conditions, minimize disassembly and assembly work to save on maintenance time and costs. They should use simple technical methods to accurately locate the fault and its cause within the shortest possible time, repair it, restore the system to normal operation, and strive to prevent similar failures from occurring in the future.

System Maintenance:

Before a system is officially put into operation, it usually requires flushing to remove pollutants, metal shavings, fiber compounds, iron cores, etc., that may be present within the system. During the first two hours of operation, even without causing complete damage to the system, it can still lead to a series of malfunctions. Therefore, the system oil circuit should be cleaned following these steps:

1) Clean the oil tank with a quick-drying solvent, then remove any residue with filtered air.

2) Clean all pipeline systems; in some cases, it may be necessary to soak the pipelines and fittings.

3) Install oil filters in the pipeline to protect the valve's fuel and pressure lines.

4) Install a flushing plate on the manifold instead of a precision valve, such as an electro-hydraulic servo valve.

5) Verify all pipeline dimensions are suitable and connections are correct.

If the system utilizes electro-hydraulic servo valves, I'll elaborate a bit further. The flushing plate of the servo valve must allow oil to flow from the supply line to the collector and then back to 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 you notice the oil filter beginning to clog, replace it immediately.

The cycle for flushing is determined by the system's design and the level of system contamination. If the sample of the filter medium has little to no external contaminants, install a new oil filter, remove the flushing plate, and set the valve to work!

Scheduled maintenance: Establish a regular maintenance system for the hydraulic system