Water in turbine oil

All turbine oils that I've tested have a water content. I've seen as little as 30PPM and as much as 2500PPM total water. My criteria for large steam turbines is anything approaching 1000PPM is a cause for concern. I guess you need to considered all the variables, type of turbine, oil and turbine age, type of filtering etc.

Hi,
Mr. rgf12
Thanks,As per vendor turbine oil should be less than 100PPM,when we collecting the sample from turbine main oil tank sampling point and analyse it is aound 50-60PPM only,but accumulation of water in oil tank bottom is too much.

Can you drain off the accumulaed water? Have you ever cleaned the reservoir? I installed sample points so I can get a sample coming from the turbine (before the tank or filter) and one in the outlet of the filter/tank so I know what is happening to the oil when it is in the turbine lube system.

We drain of the accumulated water, we did not cleaned the reservoir as it is comissioned only one year before.providing the sampling line in inlet and out let is very defficult as plant is running .

hi every body

dear salu you can take the oil sample from the equilizing valve around the oil filter and make sure that the suction pipe for the lube oil pump is far from the tank bottom.

Hi evry body
Thanks ,Vaccum unit we have to put in operation for both filtering and dewatering and its inlet connection from top of the turbine main oil tank .
From sampling point our reading are under limit 50-60ppm ,only my question is in bottom of the tank what should be the accepteble limit of water?

Salu,

The important think is the lubricant which supplied to lubricate the bearing.
That means the oil sample shall be taken from the live line zone, which the lubricant want to and/or after lubricate the bearing.

no need to much worried about the bottom of the tank.

Regards,

Nurudin

Nurudin,
Thnaks, but after one or two month high oil level alarm comes so need to drain after every one or two month.which oil goes to lubrcate the bearing that is free from moisture less than 50ppm

Yes Salu,

so, as per my consideration
* Put additional PM to drain the accumulation water from lube oil tank drain port, every month
* Continue your PdM task to analyze the oil sample from live zone.

Regards,

Nurudin

Looking at the situation one thing I would look into is why after only 1 year of service do you need to drain accumulated water from the oil tank? Most water content in turbine oil gets there from worn or leaking seals and with a newly commisioned unit I feel you shouldn't have this issue, at least not a severe one, unless there is something with the original setup of the seals that are making them leak prematurely. I would go back to the turbine OEM and get some guidance on the expected amount of leakage from the seals and if your situation is "normal". Just a thought.