Hello dear colleagues,
we are dealing with a rather "crazy" problem with our HFO S846 separator in our power plant.
More specifically, upon discharge and while on timer 66 (Leakage test) it gives an "OIL LEAKING FROM BOWL" alarm and stops. Now the "crazy" part is that this problem occurs i would say randomly or even better in unevenly time periods. It could operate for 24 hours without the slightest alarm and it could work for let's say 2 hours and bring up the problem in a short term permanent way (explaining below).
After every incident we either proceed by disassembling the bowl and checking, cleaning, replacing seals, plugs and rings or we just simply leave it for several hours idle and put in operation afterwards with 100% success (???).
During this leakage test (duration = 20 sec) the feed is cut off, V4 valve is closed and EPC is calculating the time for the PT4 pressure to fall by 1 bar. If it falls more than 1 bar then the alarm hits. So sometimes during the test the PT4 goes extremely high (around 4 bar) and then decreases quite quickly to 1 bar and the alarm is presented. In other occasions, pressure level during the test is normal (around 2.5 bar) but it jumps back and forth from timer 66 to timer 65 (multiple times), to recalculate the pressure range for the test. In the end it usually passes the leakage test successfully.
I think we have tried everything from using the whole intermediate kit replacing seals, plugs and rings to cleaning water & fuel filters, maintaining and replacing SV10, 15 and 16 water valves, cleaning the PT4 sensor, checking feed water & air pressure, cross checking again and again the functionality and the condition of the operation slide, discharge slide, operation water cover, water pump (or ring as mentioned in manual) etc, but we can't seem to solve the problem and we're going nuts!
Any suggestions, guidelines or similar experience would be highly appreciated. Thanks.
PS: I have thought changing the factory values of the duration of the leakage test (Ti 66 = 20 sec) or that of the differential pressure of the test (Fa 46= 1 bar) to let's say somehow cheat the test but.... we all know this is not recommended. What do you think though?
Bill