too big a diesel(never at full power) and "glazing"?

[Guest62110524]

Originally Posted by powerabout

It is a problem to diesel engines, the last company I worked for had a dozen anchor handlers with Warsila medium (constant with cpp) speed engines and if on standby, i.e. no load floating around the engines start to smoke, increase blowby by lots and consume lots of oil.
Not to mention the combustion blowby going into the oil as the ring sealing is not as good as it should be.
You need the combustion pressure to make the rings work.
Turbo engines are worse as in the case above as they usually have lower static compression ratios and bigger ring eng gaps
A hour at full load just about cleans it up but the engine will not last as long as one that runs with load all the time.

wartsila crossheads at that shp? OR 4 CYCLE?

[powerabout]

Originally Posted by whoosh

wartsila crossheads at that shp? OR 4 CYCLE?

2 to 7k horsepower medium speed 4 stroke, basically just like a high speed engine
some are 12V32's

PS 16,000 hrs at 60mph = 1,000,000 miles or just under 2 years non stop
Std spec for a high speed diesel in a truck.
Wartsila spec is all pistons out at 10,000hrs.
I can see why many smaller vessels are going high speed diesel electric
just swap out the engine with a recon so very little time off hire and they have a longer service life...who would ever have though that!

Originally Posted by powerabout

I can see why many smaller vessels are going high speed diesel electric
just swap out the engine with a recon so very little time off hire and they have a longer service life...who would ever have though that!

There is another reason for that. Many of these vessels rarely operate near the max power. Tugs for example see full power only between 3 and 6% of their service life, but at 80% of the time they operate below 25%. That makes a D /E installation sensible.
Other advantage is that the spare genset (there is commonly one set more than needed for max output) can be serviced while underway, no losses.

I can hardly buy these 10.000hrs. for a rebuilt (which "all pistons out" would mean) on a Wärtsilä 6/32 or 12/32

Regards
Richard

[Guest62110524]

Originally Posted by powerabout

2 to 7k horsepower medium speed 4 stroke, basically just like a high speed engine
some are 12V32's

PS 16,000 hrs at 60mph = 1,000,000 miles or just under 2 years non stop
Std spec for a high speed diesel in a truck.
Wartsila spec is all pistons out at 10,000hrs.
I can see why many smaller vessels are going high speed diesel electric
just swap out the engine with a recon so very little time off hire and they have a longer service life...who would ever have though that!

Maersk Dover if I remember correctly has these
Does not seem very long 10000 hrs especially when she runs non stop, ie no cold starts,
what do they do then , new liners and rings?

[powerabout]

Originally Posted by whoosh

Maersk Dover if I remember correctly has these
Does not seem very long 10000 hrs especially when she runs non stop, ie no cold starts,
what do they do then , new liners and rings?

ahhh no

Maersk Dover has 4 × MAN 8L48/ 60B diesels for a combined combined 38400 kW ( according to wkipedia)
our 80m boats have 11000kw combined

Yes , let me confirm the 10,000 hrs as thats the same as a 3500 cat
I do know 2 that have done more than wartsila state but last class inspection they didnt look at the hours...doh?
If I'm wrong it will only be as high as 12000 hours and they badly need rebuilding when you look at blowby and oil consumption and contamination
PS they do have anti polishing rings on the pistons to help prevent bore glazing

[Guest62110524]

Originally Posted by powerabout

ahhh no

Maersk Dover has 4 × MAN 8L48/ 60B diesels for a combined combined 38400 kW ( according to wkipedia)
our 80m boats have 11000kw combined

Yes , let me confirm the 10,000 hrs as thats the same as a 3500 cat
I do know 2 that have done more than wartsila state but last class inspection they didnt look at the hours...doh?
If I'm wrong it will only be as high as 12000 hours and they badly need rebuilding when you look at blowby and oil consumption and contamination
PS they do have anti polishing rings on the pistons to help prevent bore glazing

lazy me, I have been on this ship many times, should have googled, the engines sound heavy, but going astern the vibration is something else, the rails shake like mad, I dunno how they dont fracture something
Well thats poor from Warsila is'nt it Dover is rreally slow for such a big shp. probably cos of her stubby length

Originally Posted by whoosh

lazy me...............
Well thats poor from Warsila is'nt it Dover is rreally slow for such a big shp. probably cos of her stubby length

Well, yeah, thats really poor.

I would not call a ship of that size slow, doing 25kn. And I would not blame Wärtsilä for the installed MAN engines............

[powerabout]

Originally Posted by apex1

Well, yeah, thats really poor.

I would not call a ship of that size slow, doing 25kn. And I would not blame Wärtsilä for the installed MAN engines............

well said Apex!

Nobody spends more than 1 dollar more on a water bus than absolutely neccassary.....
Its just a design that met a price and the parts assembled by a shipyard that quoted low enough and classed by the lowest bidder.
No matter how much you spend you only get 1 year warrantee. That says it all about the commercial shipping world as far I understand it.
Thanks to classification societes most commercial shipping is designed to be scrapped in less than 10 years these days.
I know one AHTS owner who has budgeted/projected 5 years life from his (asian)vessels and believe me they will be lucky to last that long...
You cannot put a cup of tea on a table in the bridge when pulling anchors otherwise it will all spill in forward or reverse and PC's sometimes crash as the hard drives dont like it.
Norwegians have anchor handlers that are 30 years old...

(PS ) I worked on a dutch built megayacht that the yard did warratee work after 5 years for the second owner without question. The quality megayacht builders rarely build down to class

[Guest62110524]

with so much shp, the dover is not the dunkirk, but she does 22 the wl is not so long, a much longer ship with that shp would be faster, just a simple observation Powerabout thats all Maybe top is 25 but everytime I have been on them , even when running behind, they do 22 max, that is with my Magellan handheld, at slack water
you take the Emma 170000 grt, 400mlong, 25 knots, she is 5 times the weight of the Dover but nowhere near 5 times the shp,
Anyways powerabout thanks for input
where are you now
and yes nobody who wants to stay in Business builds down to a price. Best not to have any orders