Keeping contamination out is one of the key elements of maintaining hydraulic fluid lifespan. By keeping a close eye on the filters installed in a hydraulic system, it’s possible to glean some excellent insights into the overall condition of your system and an understanding of whether your filters are working properly.
Many hydraulic engineers opt to install electric clog-indicators and others will run a visual test. The former will indicate if the pressure drops due to a clog in the filter.
A more advanced approach to hydraulic filter monitoring is to install a number of pressure gauges that will indicate whether there has been a change of pressure caused by a clogged filter issue.
By continually monitoring any change in pressure caused by a blocked filter can provide an early warning of component failure. For example, if your pressure dropped from 1 Bar to 3 Bar then that could indicate imminent failure or even a major contamination ingression.
It’s important to monitor pressure and condition of oil on a regular basis. Not to do so could prove to be costly in both maintenance and production output.
There are a number of different contaminants that could block your filter. There are the hard particles such as dust and metals from wear and tear. There are also soft particles such as sludge and products from oxidation. Even if you manage to keep the hard particles within a range that is under your control, the soft particles can quickly accumulate and clog filters.
Hard particles will usually do more damage to hydraulic components than soft particles. The space afforded by clearances needs to be taken into account in addition to the shape, size and quantity of hard particles in the fluid.
Small particles can often be the most dangerous of all. They can cause wear and degradation of components.