After 200 hours of excavator use, the hydraulic oil pollution deteriorated, and the polluted oil was milky white and sticky. It was initially determined that the hydraulic system was flooded with water. Therefore, it was decided to clean the hydraulic spare parts and replace the hydraulic oil.
1. Perform oil-water separation
Considering that it may take more cost to continue cleaning, it has been decided to remove water from the system by oil and water separation. The specific implementation steps of the oil and water separation method are as follows:
(1) Prepare several clean oil drums, 2 clean and rust-free metal buckets, 2 gas tanks (filled with gas), 2 gas cookers, 1 clean scoop, 1 thermometer and some not Cotton with fluff.
(2) Discharge most of the contaminated hydraulic oil in the system from the final drives suction pipe, and pour them into two iron drums for heating (two barrels are added to shorten the heating time). When the temperature of the metamorphic oil in the oil drum rises to 78-82 °C, turn off the flame and let the degraded oil cool down slowly. Because the density of the oil is smaller than that of water, the oil and water will be separated automatically (oil on top and water on bottom).
When the temperature drops to 68-72 ° C, first use the scoop to gently pour the upper 4/5 metamorphic oil into the system, then pour the remaining 1/5 of the oil-water mixture out and store, and finally heat the barrel with cotton. Wipe dry for later use.
(3) Start the excavator to do the compound action, so that the hydraulic oil temperature rises to 50 °C, each action must be no less than 50 times, and the time is not less than 30 minutes. After the composite action is completed, the oil in the system is completely discharged and poured into the heating barrel for heating. The compounding operation was continued in the manner of steps 2 and 3, and the cycle was repeated 5 times or more. Note that new fluids should be added to the system during the cycle.
(4) After the last one cycle operation, level the excavator and fully retract the boom arm and the bucket cylinder to maximize the flow of hydraulic oil in the hydraulic cylinder and pipeline back to the tank. After the machine is turned off, the hydraulic fluid in the hydraulic tank, hydraulic travel motor, piping, travel motor and accessories is released.
Oil water separator filter
2. Oil-water separation effect
Connect the pipe joints and add the amount of hydraulic final drive motors previously released to the factory standard. Start the excavator until the oil temperature reaches 50 °C, let the machine run for 1h, observe that the oil is light yellow and the color is clear.
After 10 hours of continuous use, the oil was observed again. No deterioration was observed, and the color of the oil was still clear, indicating that the oil was basically normal. The machine was subsequently tracked and no oil was found to deteriorate again. At this point, the problem of oil deterioration of the machine has been completely solved, and it has also proved that the oil and water separation method is effective under limited conditions.
3. Preventive measures
According to the actual situation analysis, such a large amount of water can only enter from the fuel filler port of the hydraulic tank, which may be caused by misoperation. The hydraulic fuel tank cap of the machine is in a simple spin-on form and has no protective lock protection. In order to prevent the misoperation from happening again, it is decided to install a protective lock on the hydraulic fuel tank cap. https://www.spfinaldrives.com/