After years of talking about the importance, I finally got convinced to test and filter oil, since I was preaching cleanliness and Siemens was telling the power plants to change the oil or clean it.
So we tested the oil in their turbines, which to the naked eye looked clean. After pulling a sample through a 0.8 um membrane, this is what I found. (green line is 80 um - one hair-width)
Magnifying it to 400x, it looked like this
So we drained it (10,000 liters per turbine) and filtered it through Donaldson's 4 um at Beta 2000 filters, leaving it looking like this
Impressive results. We now have another dozen turbines to filter, including the new ones Siemens wants us to do before commissioning them.
So we tested the oil in their turbines, which to the naked eye looked clean. After pulling a sample through a 0.8 um membrane, this is what I found. (green line is 80 um - one hair-width)
Magnifying it to 400x, it looked like this
So we drained it (10,000 liters per turbine) and filtered it through Donaldson's 4 um at Beta 2000 filters, leaving it looking like this
Impressive results. We now have another dozen turbines to filter, including the new ones Siemens wants us to do before commissioning them.