Ship changes oil every TWO hours!

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At 42:10, they say they have to change the oil in the 9 piston, 50K bhp engine every two hours!



Yikes!

Let's have some fun, please let's all apply our BITOG funny comments to this one...
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banana2.gif
 
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On most ships I've heard the opposite, oil stays in a dry sump tank and is filtered extensively
and used over a year, sump tank is often 1,000 gallons!
 
That HAS to be a mistake.. either that, or he means that during the initial systems check process prior to its maiden voyage, it needs that.

If it DID need to be changed out that often during normal use, then on any standard voyage, I'd have to think they'd be going through potentially tens of thousands of gallons of oil on a normal tanker run... if not more.

Plus, shutting it down every two hours and draining and refilling the oil would result in ludicrous amounts of down-time every single day. Merely draining and refilling the oil from that engine could take longer than 2 hours.


.. That said, I think they should do a UOA of that 2-hour oil and send it in to Blackstone. I bet their analysis includes a comment like this:

 
sure maybe the oil gets changed but perhaps that terminology is misused as the oil might get filtered and reconditioned by some separate unit and eventually comes back to the engine. but for the purpise thata cobsidered a "change"

perhaps it means oil take a 2hours to make it back to the engine aftet going through whatever cycle it has.
 
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This is a heavy crude oil fired engine. That means it's direct drive, no gearbox. When you start the engine you're going to go somewhere right now.

The oil change comment is more of an oil maintenance cycle. The heavy oil gets cleaned and reused.
 
Just a sensationalist comment nothing to see there.

Dumbing it down to make it sound cool.
 
Maybe it circulates all the oil in the sump through the engine in two hours (seems slow but with a big enough sump anything is possible). Or fully filters/bypasses it? Or are these two stroke engines with enough lubricity in the heavy oil?
 
Whoever wrote the script didn't understand Marine Engines.

The engine lubricating oil gets centrifuged and filtered and the heavy portions of the centrifuged oil is discarded.

Due to consumption for whatever reason, new "make-up" oil is added every two hours, drawn from the reservoir.
 
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Originally Posted By: OneEyeJack
This is a heavy crude oil fired engine. That means it's direct drive, no gearbox. When you start the engine you're going to go somewhere right now.


Probably runs both HFO and LSFO because of the changes to the MARPOL Convention.
 
I was surprised to read that these engines use 30wt in the sump, I would have thought a heavier wt, given the scale of these engines. 50wt is injected at the top end, since they are two strokes. For an emergency stop compressed air is used to stop and then reverse the engine, before fuel is injected to run engine in reverse. Kinda cool I think, at least to a landlubber like me.
 
All the ships I worked on had somewhere between 800 and 1,200 gallons of lube oil. Oil/Water separator, centrifugal filter and filter chest with bats that could be re-cleaned and re-used. Typical turn-over was on the order of all oil passing the filtration system about every 4 hours if turning max revs ... Total filtration was/is a statistical exercise as some oil get recrirc'd much quicker and some does not get off the bottom of the tank for a while (tanks are baffled for rough seas).

Oil changes depended on total steaming time vs at anchor time, and UOA done every 150 hours based on the control board meters. Oil samples were taken even en route and shipped to lab from next port of call. If lab said oil was getting depleted, it was changed dockside from a pumper truck at next contracted port of call, or home port - whichever came first.

Changing ships oil is not fun or cheap...
 
My money's on bad script writing. Truly, nobody cares when a cheap production deadline comes 'round.

Believe me, a TV show made from mostly stock footage of any industrial process is the epitome of cheap production.

As stated by previous posters, likely 100% of the oil is cycled through its filtration system and topped off every 2 hours.

That cabin boys were sent into the Hindenburg's engine nacelles for 2 hour stretches to listen for abnormalities is very cool.

LESSON: Old black and white footage = truth
..............Modern color documentaries = bull fertilizer
 
Nope, the filtration is too good. Oil stays until lab says otherwise ...

You'all do know that marine lube has TBN numbers like 16 or so when new ... It's extremely robust. Labs track it down to about 4, and owners/operators start to arrange scheduled service ...

The crew can see what's in the centrifugal separator at any time they want. So they know if the engines are shedding metal or not. If no centrifugal, they can look at the batts in the filter chest every time they pull a set for exchange. Most filter chests have magnet rings just inboard and around the inlet to snag Fe metals and those get looked at too.

Chief Engineer on that ship has thousands of hours of exposure to lube systems and at least a decade in that class of ship (or next class down) w/o a major engine failure in the last ten years (or whole career). They went through the OEM simulator for engine issues. They have the recovery manuals for partial shut down, reduced power operation, etc.

To do serious in-frame overhaul of a ships engine may be a a $1/2M exercise (or more) not counting lost revenue from downtime. The 'Black Gang" will not allow that to happen. They may even be reading individual bearing heats and cylinder wall temps. They are certainly looking at individual EGT's. That engine is not going to bust or operate outside normal parameters EVER ...

You can make money with a leaking hull. You can make money with bad deck gear. You can not make a dime if it will not move. Guess where the focus is ...
 
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I think there's a lot of Molly in that ship's oil.

No, the spelling is good, a crew member named Molly fell in the 1000 gallon sump and they never managed to fish her out.
 
Originally Posted By: OPR4H
Are these the 120 - 130 max rpm kind?
Isn't that reasonable for an engine with a piston stroke near two meters? (True of some large ship engines, not necessarily this one ... )
 
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