Views:1 Author:Site Editor Publish Time: 2021-08-25 Origin:Site
Hydraulic oil can be said to be the "blood" of hydraulic machinery. Most of the faults of hydraulic systems can be found by detecting and observing the condition of hydraulic oil, so as to troubleshoot the faults.
1. The hydraulic oil is cloudy with impurities
There are three main types of impurities in hydraulic oil, namely, solid impurities (debris, solid particles, solid impurities formed by hydraulic oil deterioration, etc.), liquid impurities (mainly water, followed by viscous impurities formed by hydraulic oil deterioration) and gaseous impurities (mainly air).
If the hydraulic oil appears white turbidity phenomenon, can exclude the possibility of solid impurities or liquid viscous impurities, can only be caused by water or air. Can be used for sampling and testing hydraulic oil. Drop the oil sample on the hot iron plate. If there are bubbles (water turns into water vapor to form bubbles at high temperature), it can be determined that there is water in the hydraulic oil: otherwise, there is air in the hydraulic oil.
If there is water in the hydraulic oil to cause turbidity, the hydraulic oil will stand for a period of time, make the water sink to the bottom of the hydraulic tank, and then remove the water can be. However, if the water content is too high to emulsify the hydraulic oil, it is necessary to replace the new hydraulic oil.
If it is determined that the turbidity is caused by the mixing of air in the hydraulic oil, the pipeline of the hydraulic system should be checked for air leakage, and the mixing source of air should be cut off.
2 The temperature of hydraulic oil rises abnormally
The root cause of abnormal hydraulic oil temperature rise has the following three aspects: one is because of the relief valve pressure setting is too low, make the most of the hydraulic oil through the relief valve flow back to the fuel tank, the hydraulic system work efficiency is too low, such as the load is too large, most of the energy will shift into the hydraulic oil heat, lead to high temperature, the second is due to poor cooling effect of cooling system, leading to the hydraulic oil temperature is too high; Three is the hydraulic oil in the oil circuit circulation is too frequent (often caused by insufficient oil), resulting in heat dissipation difficulties, temperature rise.
Fault diagnosis should be easy to difficult, first check the amount of oil in the hydraulic tank, if the oil in the tank is insufficient, should be added to the standard level in time. Attention should be paid to the use of the same brand of hydraulic oil, before use should also be filtered.
If the amount of oil is appropriate, it is necessary to check whether the oil cooling system is blocked. If it is found that the oil cooling system obstructs air circulation, it should be cleaned in time to ensure normal air circulation and conducive to heat dissipation. Sometimes the fan tape is too loose or slippery, which may reduce the efficiency of the fan and cause poor cooling effect. Check and adjust the fan tape in time, and replace the fan tape if necessary.
If the oil quantity, oil cooling system, fan tape are no problem, can be judged to be the main safety valve set pressure is lower than the standard value. The pressure setting of the main relief valve should be adjusted again to the standard value.
3 The hydraulic oil is dirty
The hydraulic oil is dirty and dirty, which may be caused by chemical changes in the oil due to long-term use. There could be too many impurities and physical changes. As long as the causes of these two changes are found, corresponding measures can be taken.
In the absence of necessary testing equipment and equipment, a relatively simple and practical method to judge whether the hydraulic oil changes chemically or physically is to use filter paper for testing.
Sample the hydraulic oil, drop the oil onto the filter paper, and observe the oil halo formed by it. If the phenomenon of stratification and ring separation is obvious (dirty in the middle and clearer on the edge), it indicates that the hydraulic oil has deteriorated and must be replaced with new oil; If the oil halo is evenly spread, it means that the impurity content of hydraulic oil is too much. It is necessary to check the oil filter in time, replace the filter element, and replace the new hydraulic oil if necessary.