Alfa Laval S846 HFO Separator problem

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Mirceaa
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Re: Alfa Laval S846 HFO Separator problem

Post by Mirceaa »

Hello Fede,

Experienced Pt5 issues in the past, in my case, while opening the purifier for inspection we found a loose screw on the parring tube assembly, the arm to which the spring is attached is secured with an strew, that screw was loose so the arm/ spring assembly was not moving properly the paring tube. Screw retightened, purifier restarted Pt5 steady, no more alarms.
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Re: Alfa Laval S821 HFO Separator problem

Post by Arnav »

In main engine Lube oil purifier 821 bowl opened for bowl cleaning after that "no pt4 feedback pressure during ti59" Alarm coming. After that i started purifier without caliberation it is running ok parameters are (pt1- 0.33,pt4- 1.3,pt5- 1.2).
After every 3rd day "no pt4 discharge feedback pressure during ti59" coming.

I changed solenoid of sv10, new filter put before water valve block, flow valve of sv10 changed, parameter fa6- 0 done but still alarm coming.
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Re: Alfa Laval S856 HFO Separator problem

Post by Arnav »

"No transducer response "alarm I cleaned Mt 50 transducer, but still alarm comes, purifier don't stop when alarm comes
popeye62
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Hello Arnav. The alarm is telling you that the bowl is not filled or there is no pressure feedback. I don't believe that changing the settings is the answer unless they have been changed previously. How did you start the sequence without calibration, did you put Ti59 to 0 seconds? I would start by putting the settings back to where they were. In my manual I have: Ti59 - 170 seconds and Fa6 - 0.2b. Check all the other settings especially the factory settings (Fa) I would also increase the back pressure at PT4 to nearer 2.0b by closing in the regulating valve RV4 (the alarm range is 1.0 to 3.0b). I hear you, regarding the work done on the water supply but both alarms; the lack of feedback pressure and the lack of response from MT50 are both pointing to SV10. Why it would run for three days and then fail - I don't know. Even if there was a slow leak from the bowl or through V5 it should be made up during the separation sequence or after an ejection. Look again at SV10 and physically check the flow rate/quantity. Good luck, John.
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Re: Alfa Laval Sa 821 HFO Separator problem

Post by Dodong »

Good day engr, has anyone encounter oil leaking form the bowl?
I done all the manual instruction about this problem but still oil leaking from the bowl is alarm, i overhual the purifier and have a teflontape around the bowl orings mostly at the discharge slide, maybe previous engr put some teflon tape, water flow is correct, belt cltch pads renew, but still oil leaking from the bowl is problem,? Any one any suggestions thank you
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Hello Dodong I think we have all experienced a leaking bowl. The PTFE tape around the rubber 'o' rings sounds like an attempt to fix a sticking bowl. Have you replaced the 'o' rings and checked the grooves for damage? They should be OEM parts and have a light coating of Molykote 1000 or the anti-friction spray Molykote D321 applied. Check the speed, check the three polyamide drain plugs, check the nozzle in the bowl body, check the polyamide bowl seal; is it falling out? are there contact marks on it? Is the bowl closing at all or is it remaining open? is the water supply correct, is the throughput and temperature correct. How do you know the bowl is leaking, can you see it down the sludge chute? Is the sludge tank filling up? Are you getting any alarms, which ones?
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Re: Alfa Laval S846 HFO Separator problem

Post by Loues »

Good day sir
Nees some advise , we receive a high sediments fuel and when heated the sludge just turn to solid rubber so i always having problem with my seal ring , at first i thought it was only because of worn out and the fast accumulation of solid sludg between the sliding bowl and the bowl hood almost two seal ring i used then later i found out that this solid sludge travel always to the water drain line which is pt5 and then when i clean purifier i found the whole line is clogged and every 3 it always accumulate fast in the line so the remedy i use is at almost 30 mins i manually use open the pneumatic on the water drain and when i see a solid sludge like rubber really slow to go out so our team decide to this routine every 20 min, So maybe sir you any suggestion that can solve this problem with out manually draining the line , I already adjusted water drain timer before deslidging to maximum 30 seconds but still if not keep in monitor for atleast 20 mins line keep clogging Thank you and good day
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Re: Alfa Laval S846 HFO Separator problem

Post by dogus597 »

Hello

I have a SA821 Lo purıfıer on my ship . Two day ago The pt5 high alarm came to screen . I realized that the belt was break off . Firstly ı checked the sensor ( ıt ıs ok ) and changed belt old spare ( ı dont have new spare yet) . All bowl orıngs have been changed . But still ı have same problem and water outley sıde there ıs oıl .
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Hello Loues. There is a lot here. Regarding the fuel; what is it and what level of TSP was on the spec from the supplier and what were the results of the analysis? Has the fuel been mixed onboard? What was in the bunker prior to lifting the subject fuel? De-bunkering is an expensive business so we have to try and burn it without either destroying the engine or losing the ship because the engine won't run. The problem seems to be excessive sludge not excessive water so there should not be a problem with the water drain and there should not be any sludge in it (is the water paring chamber full of oil/sludge?). If there is a high level of sediment then a very short (try 5 minutes) separation time should be set with total discharges. Ensure the conditioning water supply and time is correct (to keep the sludge liquid as much as possible). Using the settling tank to settle out the sludge will likely not work. If possible, send a before and after sample from the separator to the lab. Can you run two separators in series to share the sediment load between them? If you can run two in parallel it will also help by reducing the throughput by half. What is the problem with the seal ring, is sludge getting trapped between the bowl bottom and the hood? A shorter separation time should prevent the space over-filling. Put the settings back to where they were especially the timers (Ti). Is the separator suction filter stopping any sediment i.e. is it blocking? If so, then this is not likely from the stem but from a dirty bunker tank. Good luck
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Hello dogus597. If the speed is OK (check it) then check that the paring tube is not stuck and is free to move.
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Re: Alfa Laval S846 HFO Separator problem

Post by eddexter »

Hello friends . Has anyone encountered pt4 low problem on purifier? Also pt4 high during ti70. Can someone share how they troubleshoot this problems
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Hello eddexter. Check the main change-over valve (V1) is working correctly. Check the valve plug hasn't dropped off.
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Re: Alfa Laval S846 HFO Separator problem

Post by Dodong »

@popeye
The alarm first is oil leaking from the bowl, when the purifier strts with no alarm oil leaking in tthe bowl it can operate about a momth but when its its stop after a day or more when it start the alarm is oil leaking at the bowl always,and i need to open and change o- ring always,btw sir popeye is water transducer can affect this alarm because the water transducer here is off mode thanks in advance
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Re: Alfa Laval S846 HFO Separator problem

Post by popeye62 »

Dodong, why is the water transducer off? How does the machine remove water if it is set up as ALCAP when it is not being detected? The water outlet is not permanently open like an old style gravity disc separator. The machine runs ok for a month but if you stop it for a day the bowl will not close, is that correct? You then open up and change an 'o' ring and it works, is that correct? Which 'o' ring do you change (is it the rectangular ring in the discharge slide)? What is wrong with the 'o' ring when you take it out? Where do you get the operating water from i.e. is it shore water or evaporator water? Is there any scale build-up in the operating water ring, the thing bolted to the bottom of the bowl? What separation time have you set? There might be an issue with the closing water. Check all the settings.
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Re: Alfa Laval S846 HFO Separator problem

Post by Dodong »

Now the water trnsducer is on, your right sir the purifier starts for q month and after i stop it now the bowl is not closing, about the oring i change it new the alarm are still there bowl leaking even it is new rectangular ring , i always change in the operating slide rectangular ring, i get the water supply in evaporator, the scale is building up at the operating slide , i set the sepaeration time in about 60mins, the closing water is good pressure and right settings
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