What is the largest ship diesel?

Discussion in 'Diesel Engines' started by DennisRB, Sep 30, 2010.

  1. RHP
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    RHP Senior Member

    Maersk ready to take plunge on 18,000 teu newbuildings
    Thursday 25 November 2010, 16:41

    MAERSK Line is in the final stages of negotiation with shipyards for a series of 18,000 teu containerships.
    Letters of intent could be signed before the end of the year, Lloyd’s List has learned.
    A considerable amount of design work still has to be completed, with several South Korean yards in the running for an order that could be worth close to $2bn.
    The ships would be of revolutionary design, with new propulsion systems and other technological advances that would considerably reduce slot costs and cut emissions.
    Lloyd’s List disclosed in August that Maersk was preparing to order ships with a nominal intake of at least 16,000 teu.
    Speculation flared again today when Korea Economic Daily reported that South Korea’s Daewoo Shipbuilding & Marine Engineering was lining up a 20-ship order with AP Moller-Maersk worth $4bn.
    A delegation from DSME is thought to be in Copenhagen this week, but a Maersk spokesman said the company had not placed an order with the yard. The Danish line would not comment on speculation about any future orders.
    Reports that the two sides were in discussion about a $4bn contract appear to be wide of the mark, with the most likely outcome a 10-ship order initially with each ship costing considerably less than $200m apiece.
    DSME has competition, though, with other shipbuilders also on the shortlist. All are thought to be from South Korea, with none from China.
    Containership prices peaked at just over $170m for a vessel of 14,000 teu nominal capacity in 2007, but have since fallen considerably.
    The Danish line has made no secret of the fact that it is preparing a newbuilding programme, but has given little away about the specification of ships it is after.
    Maersk pioneered the super-sized containership, with Emma Maersk the first of a new class of vessel, with a declared capacity of 12,500 teu. Eight sisterships, built by AP Moller-Maersk’s Odense shipyard, were delivered between 2006 and 2008. Other lines are only just catching up, with Mediterranean Shipping Co taking delivery this year of its first 14,000 teu ships, and CMA CGM now receiving its 13,800 teu newbuildings.
    Emma Maersk is 397 m long and 56.4 m wide, and the ships that Maersk is expected to order next would be bigger both in length and breadth, since there would be limitations to container stack heights.
    Engines on the new ships would probably be smaller than the 80,080 kw, 12-cylinder main engine on Emma Maersk. With slower service speeds expected to remain the norm, most ships in service today are considered to be over-powered.
    The newbuildings would almost certainly be earmarked for the Asia-Europe trades where Maersk’s sister company APM Terminals would be well-positioned to install a new generation of cranes and key facilities to handle these leviathans.
  2. apex1

    apex1 Guest

    Correct Troy,

    and in addition to your posted paper, the larger the swept volume of a cylinder, the higher the achievable efficiency. That makes these monsters worth the effort.


    make sure you know what you are talking, before you call others posts BS! As it was the case with the first petrol motor, it was with the first Diesel. It came to a first installation on boats, nothing else. You may split hairs as long as you want, calling them commercial, or successful, or what so ever. First installations were maritime, period.

  3. gunship
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    gunship Senior Member

    I'd imagine these engines work not by igniting a fuel mix to make it explode but rather by the pressure of burning diesel in the cylinders? I might well be off the mark here, but I've heard of Diesels that inject more diesel during the combustion stroke.

    And what about them engines running on more or less asphalt? those that have to mix it with water and use a microwave?
  4. Prove it or it is just BS to contradict me.
  5. DennisRB
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    DennisRB Senior Member

    Great. So it is compressed air that cranks these engines over. I could imagine the volume of air would be massive. Do these ships have their own large diesel powered air compressors on board? Do they need to run for a few hours first to pressurize large air tanks to get enough compressed air to start the engine?
  6. Yes and no. Lets say that engines this big are not started and stoppend very frequently, a container ship stays docked for not loger than 48 hours, in the meanwhile the engine is not stopped because of the necessity to power the ship with current. The cost of stopping and restarting the engine + the eventual auxiliary generation of electricity and compressed air is higher than the cost of letting it turn at idle.
    The volume of air is inversly proportional to its pressure, therefore it can be stocked in relatively small tanks.
  7. powerabout
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    powerabout Senior Member

    they do stop the main engine at the dock as that is the only chance to do maintenance.
    A crew would normally do a piston and sleeve whilst unloading should that job be scheduled.
  8. powerabout
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    powerabout Senior Member

    Class specs will state that they need X number of starts stored in tanks and that (should) gets tested during annual survey
  9. powerabout
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    powerabout Senior Member

    No just compression.

    Electronic common rail engines can and do multiple injections it makes them run very smooth.
    The worlds largest engines are electronic common rail just like the diesel in your car

    The new dual fuel ship engines that use LPG use a small diesel injection to ignite the LPG.
  10. Of course maintenance scheduling apart.
  11. rayman
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    rayman Senior Member

    that rooster from the land of the frogs is all B/S.It takes aprox. 3 revolutions of the crank to start,thats 3 seconds, slow is 55 rpm-half speed 70 and full 102 rpm. Power generation is by a bank of between 2 and 7 auxilliary engines of varying size.The main engine is attached to nothing but the propellor. Even these large engines are started and stopped on light Marine Gas Oil (diesel or distillate to poms) They just will not run slowly on heavy oil, its just the same as that black **** that goes on the roads and must be pre-heated before use. Fuel systems now use Emulsified Fuel, thats a mixture of boiling seawater and black oil, others, especially gas tankers are running on blended LPGas and diesel oil but only diesel for manouvering. Yes they have dedicated air compressors which must be running when manouvering but there must still be about 5 starts available at all times.I have sailed with 25,000hp having one rather large turbo-charger and on a 6,500 with 5 small ones. A lot depends on the maker and for starting and slow running when you are getting no boost from the turbo then an electric fan is in operation. I have sailed on a few ships equiped with a shaft generator which allows the aux. generators to be shut down when on long passages. regards ray
  12. Hmm, interesting. So you are saying that these huge engines are cranked with something different than compressed air? What cranks the engine? An electric starter? Just curious...

  13. rayman
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    rayman Senior Member

    nannyguy, no, I did not make myself very clear, they are all rotated to start by compressed air, that gear you see on the crankshaft is for the turning gear, used to rotate when doing adjustments and clearances.When starting,place fuel lever at slow run position-place air lever(or wheel) to start position-count 1-2-3-then bring back to run position and your engine should be running. Thats the shorts of it.You may have read accounts of yachties and others in distress where a ship has come over the horizon, passed close by but kept on its way, then another appears from the opposite direction and rescued/helped them.They do not realise the the ship has to activate the engine room, change fuel, it can take 30minutes to run the heavy oil out and get to run on diesel, open up the air system, get the engine ready for maneouvers then return to the distressed vessel.Thats about it in a short story. The largest I have sailed with was 28,000 hp. Mitsubishi-Sulzer Super RND but they are all pretty much the same.I have walked onto a Russian ship and a Japanner with not a thing in English but once again, all systems and layouts are the same.
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