Why Does Hydraulic Oil Turn Black--Sinocmp

Why Does Hydraulic Oil Turn Black--Sinocmp

Reasons for Komatsu excavator hydraulic oil blackening

1. Internal impurities:

Metal impurities such as iron filings are the main factors that affect it, and the most likely is abrasive debris generated by the high-speed rotation of the pump. It is currently understood that as long as all parts rotating with the pump are possible, such as the wear of bearings, volume chambers, etc. At the same time, the spool of the hydraulic valve runs back and forth, and the debris generated by the back and forth operation of the cylinder. But this phenomenon will not occur in a short time.

Of course, if your excavator is newly purchased, a lot of metal impurities will be generated during the running-in. It is recommended to completely empty the hydraulic oil in the oil tank when changing the oil, wipe all the oil tank with cotton cloth, and then add new oil . If it is not emptied, there may be a lot of iron filings remaining in the fuel tank, which will also cause the new oil to be contaminated and blackened.

2. Affected by the external environment:

① The excavator is not tightly sealed due to mechanical failure, aging of oil seal and other reasons;

② The working environment of the excavator is too bad and the filter element is blocked;

③ Dust-preventing measures are not done well in the process of cleaning, oil change and maintenance, and impurities are brought into the hydraulic system during operation.

Here, it is recommended that you check whether your hydraulic system is closed, whether the breathing hole is intact, check the Outside parts of the hydraulic part of the equipment, and see if the seal is intact, such as the dust ring of the cylinder.

If your excavator often uses the Excavator Hammer, the cause of the blackening of hydraulic oil is not only impurities, but also caused by irregular filling of butter.When filling the butter, the breaker needs to be lifted, and the steel brazing is pressed into the piston. Each time, only the half of the standard grease needs to be filled. Because if the steel brazing is not compressed when filling the butter, the butter filled at this time will be at the upper limit of the steel brazing groove. When the steel brazing is working, the butter will directly jump to the main oil seal of the breaker, with the piston The reciprocating movement brings the butter into the cylinder body of the breaker, and then the hydraulic oil in the cylinder body of the breaker is mixed into the hydraulic system of the excavator. The hydraulic oil is deteriorated and blackened.

According to statistics, about 70% of excavator hydraulic system failures are caused by improper selection of hydraulic oil, careless use, and untimely replacement. Therefore, the correct and reasonable use and replacement of hydraulic oil is an important condition to improve the performance and economic performance of the hydraulic system of the excavator and extend its service life.

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