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What brand is considered the absolute best? Durability, economy, power, the best overall value?

What is the flip side, the biggest POS afloat?
 

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Well, this is a "multilevel" question, different types of vessel designs have different power and design requirements.

For sheer large, fuel efficient high power range requirements- the Slow Speed, Two Stroke, Direct Reversing Diesel...

For smaller vessels- Medium to High Speed 4 Stroke Diesel, coupled to either a mechanical or electrical transmission device.

For High Speed Vessel and Naval Combatants- Gas Turbine....

We could go on for a millennium describing sub sets and categories, but
there's a lot of different configurations, generally mission specific.

Personally, it's my firm belief that over THE ENTIRE 25 year life cycle of a vessel, that when you factor in ALL maintenance and parts, fuel, consumables, that the Geared Steam Turbine would win hands down easily... However, the IMMEDIATE cost savings are such that Owners and Operators prefer the short term savings of a "12 to 15" year vessel with Slow Speed Diesel...
 

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Oh, the absolute worst performing, maintenance intensive, unreliable machinery config was the original Yanmar Gensets on the USL Econs !
 

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Personally, it's my firm belief that over THE ENTIRE 25 year life cycle of a vessel, that when you factor in ALL maintenance and parts, fuel, consumables, that the Geared Steam Turbine would win hands down easily... However, the IMMEDIATE cost savings are such that Owners and Operators prefer the short term savings of a "12 to 15" year vessel with Slow Speed Diesel...
Agree entirely with that - Whilst the vessel is at sea - however Port consumption needs factoring in, OCL's "Baby Bays" would burn 30TPD in port under steam just to keep the lights on.

As you so rightly point out though charterers concentrate on the fuel consumption more than the amortised daily rate so the cost analysis is only really true for owned tonnage.
 

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IMHO (which is nonsence of course - I dont have humble opinions ;))

In terms of absolute thermal efficiency four strokes will always win and of them the dual fuel Warsillas are top of the heap, however as propulsion they have too many losses hence the preference for direct drive two strokes.

in terms of running costs turbines of course require less spares and maintenance - however the shear quantity of fuel required - almost double , together with forever increasing two stroke service intervals means that they dont even come close to two strokes short medium or long term in terms of cost. just by way of an example using fairly arbitary figures

assuming say $500 per tonne of fuel oil

two stroke - 50 tonnes a day = $25000 /day

Steamer - 100 tonnes per day = 50000/day

cost of overhauling engine at 5 years = 100,000 = 4 days extra fuel for steamer

even if you factor in CLO and spares, steam just cannot compete - even with the latest reheat systems they are still at least 1.5 times less efficient. So im afraid the poor old steam ship - of which I am one the biggest fans just cant touch the stone crushers.

So in general modern terms my favourite engine - MAN B&W 6S70ME
I am however not the biggest fan of the Wartsilla DFs with DF50 in particular a work in progress and a case point that simply scaling up from a DF36 (a fine established engine) does not work

my favourite historical engine - Stal Laval AP turbines
least favourite - anything with the words Peilstick, paxman or hedemora on the side - but Mr Pielstick in particular I hope is inhabiting his own special circle in Hell
 

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Ben Line done a feasibility study on a steam turbine ship to Far East using the suez canal for some of the reasons above came to the same conclusion that there was not much in it,with the extra speed if necessary so the last of the BENLEDI class was given a steam turbine BENCRUACHAN after completion the canal was closed for 7years(?HUH)
 

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Ben Line done a feasibility study on a steam turbine ship to Far East using the suez canal for some of the reasons above came to the same conclusion that there was not much in it,with the extra speed if necessary so the last of the BENLEDI class was given a steam turbine BENCRUACHAN after completion the canal was closed for 7years(?HUH)
one of the saving graces that turbines had was the power available - that has long gone, and with bunker prices much more expensive nowadays together with 5 yearly maintenance intervals I'm afraid turbines don't even come close to being economic and by not close I mean not even in the same book never mind page
 

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Its always been thus, Running costs and builders costs (Capital). Even in the glory days unless a sister ship in all respects, aship built was novel, and spares and upkeep were the additional unspoken costs. Probably the SD14 from Sunderland Yards were the nearest to an economic investment and return, for general use and trading. Most ships were built and designed for a specific charter, trade and port restrictions, so if you can name a trade that is general, or bulk from any port or groups of ports, you should become a ship owner/charter of the future and make your millions. Good luck.
 

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Another consideration in cruise ship and ferry applications is the height of the engine. Wartsila is the standard choice for cruise ships, with four or six motors, sometimes in two sizes, all powering alternators to flexibly provide electrical power as needed for propulsion and hotel consumption. MAN is popular in ferry applications, with MTU engines in fast ferries.
 

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Another consideration in cruise ship and ferry applications is the height of the engine. Wartsila is the standard choice for cruise ships, with four or six motors, sometimes in two sizes, all powering alternators to flexibly provide electrical power as needed for propulsion and hotel consumption. MAN is popular in ferry applications, with MTU engines in fast ferries.
Fair comment, the ubiquitous two stroke is not suitable for every vessel and with such things as azipods and the like diesel electric comes into its own.

There is another consideration which is in the post and that is the IMO tier 3 emission rules. This is a complicated area with an absolute myriad of variables including a lot exhaust gas post treatment and when you throw in gas fueling we end up running Diesel engines in Otto cycle - there is a potential mini 'format' war brewing - should be interesting
 

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Ships Engines

I may be living in the past but for simplicity of maintenance, and with advent of hydraulic spanners etc. none could beat the Doxford or B&W opposed piston two strokes.
 

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Any ideas where I can find information on Stal Laval AP turbines. I had info for my chiefs but alas in Burntisland tip now !
the handbook by the service engineers is the info you are looking for? Apart fro you who sailed on one of these plants you have your fellow engineers from OCL who had ships with this plant/machinery. Good luck in your hunt.
One of the problems with the Stal AP turbine sets of the 70,s was the epicyclic gear boxes, built and designed serviced By ALLENS? of {plant in the black country-worcester???]. The gear boxes after a time in service on the designed SHP output where subject allegedly subject to stringent inspection. AT this time suez was closed?
There where no problems allegedly with the main impulse turbine sets. The astern turbine was in the LP turbine case/shaft out put and was a larger dia wheel TWO stages only astern Blades???
Boiler s for the ships were of interesting design, not two equal boilers but one and a half or one and a quarter boilers for the main plant. The main boiler the designed output max SHP-- the quarter/ half boiler to steam the plant in case of mishap safely at reduced speed power into port. Interesting times for these TUrbine sets which as individual units were designed to deliver 45,000 KW on the shaft, as a basic.
 

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ah lads now quitetly passing the day the only marine engine I hear is and that I enjoy is a single cylinder 'bolenger'' as a barges passes me on the towpath of the local canal! Smoke rings to you all?? I blow with my kisses xx Duckie!!!
 

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Cheers Dave indeed the Danish class and the Sweden were the 1.5 boiler config, the reduction gearing at times sounded like a bag of nuts and that was the technology in its day....
 

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Any ideas where I can find information on Stal Laval AP turbines. I had info for my chiefs but alas in Burntisland tip now !
Ingvar Jung's 3 volume History of The Marine Turbine is a good source, if you can get hold of a copy (Published by the NMM) Somewhere I have a photocopy of the AP manual - if I can find it I'll scan it.
 

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Texaco Denmark had a Stal Laval AP turbine and an epicyclic gearbox which were trouble free but the boilers, a Combustion Engineering V2M8 and V2M9 were very highly strung and required constant cajoling to perform. The rotary air heater was inclined to go on fire, wee fires as we were all concerned about being toasted and kept constant watch on the air side/gas side temperatures.
The above may be a bit superficial but I was the lowly Engine Cadet and a bit overawed by it all.
 
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