A proper tank has the following:
- For maintenance purposes a reservoir should have an inspection cover.
- A filter breather for air exchange.
- Protection for filler plug and drainage pipe.
- Oil level sensor with thermostat.
- Connections for suction discharge and drain lines. These lines should be situated as far apart as possible.
The level of fluid in a hydraulic tank is very important. If the level is too low, there is a chance of air getting entrapped in the reservoir outlet pipeline going to the pump suction. This may lead to cavitation of the pump resulting in pump damage.
The temperature of the fluid in the reservoir is also important. Required to be mounted on the reservoir a thermometer whose ideal temperature range is around 40 °C to 60 °C.
But in the field I found different story. Also depends on the region. I discovered thermometers with value between of 60°C to 80°C. Indeed if the temperature was more than 80°C then the hydraulic equipment was cut off.
Method of cleaning the hydraulic tank
A clean hydraulic tank
The hydraulic machinery should be stopped. A warning about tank cleaning and safety sign to main breaker required to be used. No compromise on safety.
Connect a hose to the drain cock at the bottom of the oil tank, and drain off the oil into clean empty barrels or drums.Remove the tank cover. Scrape off sediment, if any, from the tank bottom and sides using a rubber scraper.
Flush the tank with white spirit. Wipe the tank dry with clean rags. Don’t use cotton waste or other linen material.
Close the drain cock and replace covers. Check that the rubber seals between covers and tank are perfectly tight. Fill oil to just under the maximum mark on the oil level indicator. Use recommended oil. If the drained oil is in good condition and can be used, it should be filtered before refilling.
Pump and hoses used for filling must be perfectly clean.
Check that the drain cock does not leak.