How to maintain the hydraulic system of
system is put into general are before after washing, the washing purpose is to remove residual contaminants in the system, scrap metal, fiber core compounds, etc., in the first two hours of work, even if not completely damage the system will cause a series of failures. Therefore, the following steps should be taken to clean the system circuit:
(1) cleans the tank with a dry cleaning solvent and cleans the solvent residue with filtered air.
(2) clean all the piping of the system. In some cases, the pipes and joints need to be impregnated.
(3) installed in the pipe oil filter to supply line and pressure line protection valve. The
(4) is equipped with a flush plate instead of a precision valve, such as an electrohydraulic servo valve.
(5) check that all piping dimensions are correct and that the connections are correct. Use of electro-hydraulic servo valve
system if, as I might say a few words, the servo valve to flush the plate to make the oil from the oil pipeline to the collector, and return the tank, allowing the oil circulation to flushing the system repeatedly, let the oil filter out solid particles, washing process, no every 1 to 2 hours to check the oil filter, oil filter to prevent pollutants is blocked, this time not to open the bypass, if found oil filter immediately began to block oil filter. The cycle of
washing is determined by the system structure and the extent of the system pollution. If the filter medium has no or very little foreign contaminants, a new oil filter is installed, the flushing plate is removed, and the valve is installed!
planned maintenance: the establishment of regular maintenance system, the hydraulic system maintenance system is recommended as follows:
(1) at most 500 hours or three months, we must check and replace oil filter.
(2) regularly flush the inlet oil filter of the oil pump.
(3) check that the hydraulic oil has been contaminated by acidification or other contaminants. The odor of the hydraulic fluid can be roughly identified whether or not it has deteriorated.
(4) repair leaks in the system.
(5) ensure that no foreign particles enter the tank from the breather cap, the oil filter plug seat, the gasket seal of the return line, and the other openings in the tank. The reason of

cylinder noise fault caused by
to solve the fault cylinder noise there are three main types of noise, noise of the 1. plunger pump or motor piston rod 2. overflow valve and the piston rod of the hydraulic cylinder piston rod 3. three categories have different reasons for noise fault investigation, noise


1. plunger are as follows pump or motor piston rod of the hydraulic pump valve plate (1) is one of the important components of the noise caused by easy. When the valve plate is in use, because the surface abrasion or sludge deposit at the opening of the unloading slot, the unloading groove is shortened, and the unloading position is changed, and the phenomenon of oil trapping is generated, and then higher noise is caused. In the normal repair process, the flat plate grinding repair of the port plate will also appear unloading slot short consequences, at this time, if not in time, the appropriate slender, will also produce larger noise. In the assembly process, the large unloading groove of the valve plate must be installed in the high pressure chamber of the pump, and its sharp angle direction must be opposite to the rotation direction of the cylinder block, otherwise it will bring greater noise to the system.
(2) the internal components of the hydraulic pump such as excessive wear, the cylinder piston pump and valve plate, the plunger and the plunger hole with pieces of the wear and tear, injury, make a serious leak in the hydraulic pump, when the hydraulic pump output pressure and flow pulsation will produce small flow oil, causing high noise. At this time, the deflection angle of the variable mechanism of the pilot system can be appropriately increased to improve the influence of the internal leakage on the output flow of the pump. The piston spool valve, hydraulic pump to control the flow of local wear, because of injury, so that the piston pulsation in the process of moving, causing the hydraulic pump output flow and pressure fluctuations, resulting in larger vibration and noise at the outlet of the pump. At this time, wear, strain, serious components brush plating, polishing or replacement treatment.
(3) suction is one of the main causes of excessive noise in hydraulic pumps. When the oil is mixed with air, it is easy to form cavitation in its high pressure zone and propagate in the form of pressure wave, resulting in oil oscillation, resulting in cavitation noise.
2. overflow valve piston rod noise,
overflow valve prone to high-frequency noise, mainly pilot valve performance instability, that is, the pilot valve front chamber pressure, high-frequency oscillation caused by vibration of the air generated by noise. The main reasons are as follows:
(1) pilot valve due to fatigue deformation of the spring, resulting in its unstable pressure regulating function, causing large fluctuations in pressure and noise, at this time should replace the spring.
(2) needle in the process due to the frequent use of open and excessive wear, the cone valve and valve seat can not be closed, causing the pilot flow instability and pressure fluctuations caused by noise, this time should be timely repair or replacement.
(3) is mixed with air, and cavitation is formed in the front of the pilot valve to cause high frequency noise. At this point, the air should be discharged in time and the outside air should be re entered.
3. hydraulic cylinder piston rod noise
(1) cylinder head oil seal is too tight or piston rod bending, in the course of movement will also due to noise. At this point, it is necessary to replace the oil seal or correct piston rod.
(2) is mixed with air or liquid in the hydraulic cylinder. The air is not completely discharged, and cavitation happens under high pressure, which leads to larger noise. At this point, air must be discharged in time.

according to the above reasons one by one to investigate, you can find the problem. How does

rapidly determine the leakage in the hydraulic cylinder of a loader?