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Most powerful cargo ships?

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  #1  
Old 7th April 2009, 23:01
Steve Hodges Steve Hodges is offline  
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Most powerful cargo ships?

I have always believed that the eight Sea-Land container ships built 1972-73 with 120,000 shp twin screw steam turbines and 30knot service speed, must have been the most powerful engine installations ever in commercialcargo ships as opposed to passenger liners. Am I right, or was there anything built more powerful?
Also, I would be interested to know if any SN members have any personal experience of these ships and their engines when they were in commercial service. I understand they were all taken over by the US Navy in 1981-82, and converted for part Ro-Ro operation, and are now known as the Algol-class - I think they kept their original boilers and turbines. All are now in the U.S.Reserve Fleet
They were Sea-Land Commerce, Sea-Land Exchange, Sea-Land Finance, Sea-Land Galloway, Sea-Land Market, Sea-Land McLean, Sea-Land Resource and Sea-Land Trade, all 41,127 tons gross and US flagged.
Anyone out there had first hand knowledge of them?
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Old 8th April 2009, 04:02
surfaceblow surfaceblow is offline  
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I sailed on the Sealand Market for one trip in 1975. At that time the ship was running 24 to 26 knots for the North Atlantic run using 2212 gallons of fuel an hour burning Bunker C.

The plant was non automated to save on paying the engineers 10 per cent automation pay. All of the main steam stops were manual operated but at the time I was on the Market an impact wrench was used to open and close the steam stops. The Engine Room contained two steam plants with crossovers between them. Each plant had one boiler, two feed pumps, Main Turbine Condenser and DC Heater plus the auxiliaries. There was a Stby Diesel Generator in one of the Shaft Alleys. Each watch had a Second and Third Engineer on watch plus two QMED's. The 4-8 watch transfered fuel, 8 - 12 watch took care of the water the Second did the boiler test, The 12 - 4 Watch took care of the lube oil systems. Filling the log book took most of the watch. The time changes was two hours per night. The Mates Union required that the ship have Second Mates for the Deck watches plus a day Second Mate since the Engineers Union had two Engineers on watch.

Joe

Last edited by surfaceblow : 8th April 2009 at 04:11.
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Old 8th April 2009, 04:17
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Was there a Sea-Land ship that used gasoline?
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  #4  
Old 8th April 2009, 08:20
Steve Hodges Steve Hodges is offline  
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Quote:
Originally Posted by surfaceblow View Post
I sailed on the Sealand Market for one trip in 1975. At that time the ship was running 24 to 26 knots for the North Atlantic run using 2212 gallons of fuel an hour burning Bunker C.

The plant was non automated to save on paying the engineers 10 per cent automation pay. All of the main steam stops were manual operated but at the time I was on the Market an impact wrench was used to open and close the steam stops. The Engine Room contained two steam plants with crossovers between them. Each plant had one boiler, two feed pumps, Main Turbine Condenser and DC Heater plus the auxiliaries. There was a Stby Diesel Generator in one of the Shaft Alleys. Each watch had a Second and Third Engineer on watch plus two QMED's. The 4-8 watch transfered fuel, 8 - 12 watch took care of the water the Second did the boiler test, The 12 - 4 Watch took care of the lube oil systems. Filling the log book took most of the watch. The time changes was two hours per night. The Mates Union required that the ship have Second Mates for the Deck watches plus a day Second Mate since the Engineers Union had two Engineers on watch.

Joe
Cheers, Joe! The membership of SN is like a human encyclopedia, you just have to ask!
Some questions that you might be able to answer for me -
- Anything special about the boilers? What were the steam conditions?
- I saw one of this class fitting out at Emden; the after superstructure looked very tall, as if most of the boilers were above main deck level. Was this the case?
- Did the turbines have extra nozzle sets for high-speed running?or was it just a question of opening the stops further( with the impact wrench!!)
- I presume these ships were built with a US Government/Navy subsidy, were there any other special features that reflected this apart from the power and speed ?
-I've seen 33 knots claimed for these ships - what did the crew reckon was flat-out top speed?
- I believe all the accomodation was right for'ard. Any problems with this at high speed?
Thanks
Steve H
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  #5  
Old 8th April 2009, 11:20
Pilot mac Pilot mac is offline  
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Steve,
I believe this class held whatever colour ribband it was for both Atlantic and Pacific Oceans and I dont know if it has ever been beaten. I recall average speeds were in excess of 30 knots. I sailed on a couple of Sealand Ships that also had all accomodation forward, no problems with weather but you certainly pull her back more readily when you can hear the noises underneath you. When pitching heavily the 'whistling' from the fore peak vents was awesome. Although the ships steered well it was very dificult for the helmsman to steer 'steady' as there is nothing to reference on ie nothing to see out of the bridge windows. One of the ships was named after McLean arguably the person that really put containers on the oceans. In the early days everyone considered standardisation to be the norm ie boxes were either 20' or 40', wrong ,Sealand conned the world as there standard box was 35' but Sealand ships were designed to take either 35's or 40's or 20's. It made it very dificult for other operators to carry Sealand containers but Sealand could carry theirs.
Steve, I notice from your profile that you are an engineer, down side to frd accomodation- bloody long way to go when you are on the bells.

regards
Dave
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Old 8th April 2009, 16:06
surfaceblow surfaceblow is offline  
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There was nothing special about the boilers just that they were bigger and use very little brick work in them. You could slide down the down comer to the mud drum. The boilers were position high in the engine room the burners were a few steps up from the operating platform. The burners were short, fat and heavy. The Steaming condition was 1000 plus psi and 950 F superheat temperature if I remember correctly. I remember shutting down one boiler when coming into Flexstowe to do boiler work and we were still able to maintain 21 knots on one boiler.

The big difference was going up in speed or dropping the speed above maneuvering full. It was done in 5 psi every 5 minutes increase in the first stage pressure to slowly increase the temperature of the turbines. The turbines using a lifting beam arrangement for selecting the number of nozzles in use normally I do not remember any extra nozzles. The Turbine controls was a little plastic knob to increase or decrease the turbine speed just like on the switchboard for the generators governors. I do not know what the top speed was by the time I was on the Market there was a economy operation due to the fuel cost. The only reason that we picked up speed on that trip was for a container that was promised to be delivered by a certain day.

On the SL -7's the engineers lived aft above the engine room and the mates lived forward. Under the fwd house was a water tank for them. The mates would use very little water so it about a ton a day but when the weather was nice they would go and use 10 tons in 12 hours. The After house had doors opening fwd that you could not open while underway from the wind pressure on the house. Sleeping on the ship was like on a sail boat always pushed over to one side. It was alright if you were wedged in against the bulkhead. If the ship was leaning the other way then the extra blanket was put under the mattress to bring the corners up.

After the navy took over control of the SL-7 s the boilers were switch to burn diesel fuel they had a problem with fires in the economizers due to too much air and the unburnt fuel catching fire high in the stacks. They also had to derate the speed of the vessel since the steam superheat temperature was lowered and the turbine blades were getting condensate impingement.
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Old 8th April 2009, 23:55
Klaatu83 Klaatu83 is offline  
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It must have been quite an experience sailing on an SL-7. As I recall, their total horsepower was 120,000, and they could do 33 knots.

They represented instances of both bad AND good timing. Sealand built them just before the 1973 oil crisis, when people lined up around the block to buy gasoline at the then-exorbitant price of fifty cents a gallon. It made the eight ships instant white elephants. Then, in the wake of the Iran hostage crisis of 1979, the U.S. Department of Defense suddenly decided that what they needed were large, fast cargo vessels. Just as suddenly as in 1973, Sealand found themselves in the right place at the right time. The government made them an offer, and they jumped at the chance to unload their eight fuel-hungry monsters. The ships are still around; re-named, re-painted and converted into Ro-Ros.
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Old 12th April 2009, 13:40
Philthechill Philthechill is offline  
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Thumbs up Hansa Line.

Quote:
Originally Posted by Pilot mac View Post
Steve,
I believe this class held whatever colour ribband it was for both Atlantic and Pacific Oceans and I dont know if it has ever been beaten. I recall average speeds were in excess of 30 knots. I sailed on a couple of Sealand Ships that also had all accomodation forward, no problems with weather but you certainly pull her back more readily when you can hear the noises underneath you. When pitching heavily the 'whistling' from the fore peak vents was awesome. Although the ships steered well it was very dificult for the helmsman to steer 'steady' as there is nothing to reference on ie nothing to see out of the bridge windows. One of the ships was named after McLean arguably the person that really put containers on the oceans. In the early days everyone considered standardisation to be the norm ie boxes were either 20' or 40', wrong ,Sealand conned the world as there standard box was 35' but Sealand ships were designed to take either 35's or 40's or 20's. It made it very dificult for other operators to carry Sealand containers but Sealand could carry theirs.
Steve, I notice from your profile that you are an engineer, down side to frd accomodation- bloody long way to go when you are on the bells.

regards
Dave
Dave! Read your comments about the helmsman having problems holding a straight course as there was nothing to see out of the bridge windows.

I remember seeing the German Hansa Line heavy-lift ships out East and they had their accomodation perched, virtually, on the fo'c'sle and, to overcome the steering problems you mention, had a huge boom sticking out from the bow. Salaams, Phil
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  #9  
Old 22nd April 2009, 02:00
riverdiver riverdiver is offline  
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Back in the early 80's I sailed on the Sealand D-9s and a lots of my shipmates sailed on the SL-7's the AB's had to go back to Piney Point MD, SIU school for Quartermaster training while the ships where getting built , you had to be a Quartermaster to stand wheel watch. I did here the story that when they set the record for the fastest time across the Pacific that the sea's broke all the windows out in the wheel house.
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  #10  
Old 23rd April 2009, 16:44
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Ian J. Huckin Ian J. Huckin is offline  
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Quote:
Originally Posted by Philthechill View Post
Dave! Read your comments about the helmsman having problems holding a straight course as there was nothing to see out of the bridge windows.

I remember seeing the German Hansa Line heavy-lift ships out East and they had their accomodation perched, virtually, on the fo'c'sle and, to overcome the steering problems you mention, had a huge boom sticking out from the bow. Salaams, Phil
Lakers, with fwd accom, also have the boom to give a reference point for steering....
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  #11  
Old 23rd April 2009, 16:46
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Ian J. Huckin Ian J. Huckin is offline  
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Originally Posted by Ian J. Huckin View Post
Lakers, with fwd accom, also have the boom to give a reference point for steering....
Rumor has it that on Canadian Lakers the helmsman looked out the wheelhouse aft windows to get an even better reference...
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  #12  
Old 27th April 2009, 22:24
Enginear Enginear is offline  
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I sailed on three of the SL 7's, the Exchange, MClean and Trade. They all did 33 knots or better depending on the currents and wind. The only trouble was at that speed within 24 hours either the superheater or the economizer would let go.
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Old 19th May 2009, 02:58
steamer659 steamer659 is online now  
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I sailed on the USNS Algol (Sea-Land Exchange) as First Asst Engr- these vessels were originally steamed at 33.25 Knots, four on the east coast, four on the west coast. One held the westbound (?) Transpacific freight crossing record and one held the eastbound (?) Transatlantic crossing record. The boilers were very unique in that they had two rows of unheated downcomer tubes on the EXTERIOR of the boiler casings one on each boiler side. Further, the burners were the largest that I have ever seen (by far) and each burner had (originally) a primary as well as secondary air foil (diffuser), the primary ones were originally movable and were taken out of service in the early years after delivery. The average fuel burn was 5000 bbls a day at full sea speed. There were also a significant amount of condenser problems in way of the salt water side- remember that these vessels had an 84" main injection scoop, and that you HAD to be on the scoop to get enough sea water flow to the condenser- at any rate- the water velocity flowing through the tubes was so great that they had velocity induced fatigue failures- later brought under control by inserting plastic laminar flow guides which slowed the water flow down... The strut bearings on these monsters were a legend in themselves...
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Old 8th August 2009, 01:08
Peter B Peter B is offline  
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SL-7's possibly beaten

The Sea-Land SL-7's are a legend at sea. I first heard of them in 1980 as I was an apprentice in Albert Maersk, a 40,000 shp steam turbine powered container vessel built at Blohm + Voss, Hamburg in 1975.

The question is; have more powerful merchant ships seen the light of day?
I think the answer is yes, as the Emma Maersk and her seven sisters have the potential of "feeding" the single propeller shaft with approx. 133,400 bhp, using the combined power of the main engine (~109,000 bhp) and the two electric shaft motors (9 MW (~12,240 bhp) each).
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Old 8th August 2009, 02:19
johnb42 johnb42 is offline  
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Quote:
Originally Posted by surfaceblow View Post
I sailed on the Sealand Market for one trip in 1975. At that time the ship was running 24 to 26 knots for the North Atlantic run using 2212 gallons of fuel an hour burning Bunker C.

The plant was non automated to save on paying the engineers 10 per cent automation pay. All of the main steam stops were manual operated but at the time I was on the Market an impact wrench was used to open and close the steam stops. The Engine Room contained two steam plants with crossovers between them. Each plant had one boiler, two feed pumps, Main Turbine Condenser and DC Heater plus the auxiliaries. There was a Stby Diesel Generator in one of the Shaft Alleys. Each watch had a Second and Third Engineer on watch plus two QMED's. The 4-8 watch transfered fuel, 8 - 12 watch took care of the water the Second did the boiler test, The 12 - 4 Watch took care of the lube oil systems. Filling the log book took most of the watch. The time changes was two hours per night. The Mates Union required that the ship have Second Mates for the Deck watches plus a day Second Mate since the Engineers Union had two Engineers on watch.

Joe
Without sounding rude, Joe, most of the technical stuff goes over my head. The bit that sinks in is the "Time changes was two hours per night". I spent some time on the CP box boats where the time change was one hour per night, and I remember the homeward or Eastbound passages being killers even when I was a young, fit and healthy man. Two hours per night must have been real ball-breakers.
John
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Old 8th August 2009, 02:41
surfaceblow surfaceblow is offline  
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Originally Posted by johnb42 View Post
Without sounding rude, Joe, most of the technical stuff goes over my head. The bit that sinks in is the "Time changes was two hours per night". I spent some time on the CAP box boats where the time change was one hour per night, and I remember the homeward or Eastbound passages being killers even when I was a young, fit and healthy man. Two hours per night must have been real ball-breakers.
John
It certainly was not fun. The schedule had a five day passage. The norm was we did not change time on the first and last days so we would be on local time for the log book entries. So that left three days to change 6 hours for Port Elizabeth New Jersey to Rotterdam.

Joe
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Old 8th August 2009, 02:46
johnb42 johnb42 is offline  
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Sorry all,
I spent time on CP box boats - Tilbury, Rotterdam, Le Havre, Quebec and back. Not CAP box boats. Keyboard out of control again.
John
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Old 8th August 2009, 06:49
Billieboy Billieboy is offline  
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The best thing about the sale of the 7s was that it was only after the US-Govt had bought them, that they discovered that lower decks would have to be strengthened and new Ramps would have to be built to take the M1 tanks at 120tons. The US yards must have made a mint!
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  #19  
Old 26th August 2009, 12:42
Abbeywood. Abbeywood. is offline  
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SL-7's

Does anybody know which of the SL-7's was drydocked in the King George V Graving dock in Southampton, sometime during the late '70's.
If memory serves, she had problems with her propulsion shafting etc.
Whatever, she was docked under a full load of 'boxes'.
Suspect it may have been 'Sealand Galloway'
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Old 8th September 2009, 13:03
David Ambrose David Ambrose is offline  
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Originally Posted by steamer659 View Post
I sailed on the USNS Algol (Sea-Land Exchange) as First Asst Engr- these vessels were originally steamed at 33.25 Knots, four on the east coast, four on the west coast. One held the westbound (?) Transpacific freight crossing record and one held the eastbound (?) Transatlantic crossing record. The boilers were very unique in that they had two rows of unheated downcomer tubes on the EXTERIOR of the boiler casings one on each boiler side. Further, the burners were the largest that I have ever seen (by far) and each burner had (originally) a primary as well as secondary air foil (diffuser), the primary ones were originally movable and were taken out of service in the early years after delivery. The average fuel burn was 5000 bbls a day at full sea speed. There were also a significant amount of condenser problems in way of the salt water side- remember that these vessels had an 84" main injection scoop, and that you HAD to be on the scoop to get enough sea water flow to the condenser- at any rate- the water velocity flowing through the tubes was so great that they had velocity induced fatigue failures- later brought under control by inserting plastic laminar flow guides which slowed the water flow down... The strut bearings on these monsters were a legend in themselves...
When I worked at Foster Wheeler, we sold a boiler to the National Gas Turbine Establishment at Pyestock, which I think was based on the SeaLand boilers. Did the furnace extend below the water drum, like a power station boiler? Certainly the downcomers were huge.
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Old 26th November 2011, 05:39
steamer659 steamer659 is online now  
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Just as a post-script, I am currently Chief Engineer on the SS Algol (ex- Sea-Land Exchange).

I am rather amused at some of the above posts, as some are accurate; others not so accurate. The vessel's boilers are basically unchanged from the original configuration except for new and improved burners. Superheater Outlet Pressure is still the same- 875 PSIG (remember that due to the pressure drop across the superheater, the drum pressure runs nearly 1000 at full sea speed) at 945 F. This vessel is still capable of speeds above 33 knots, but yes- they literally suck the fuel out of the settling tanks- somewhere around 4500 barrels a day...they can run on 180 or Gas Oil. For 37 years old- most of the eight vessels are in outstanding condition- and if manned with good engineers- still remainthe fastest cargo ships in the world.
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Old 26th November 2011, 05:53
steamer659 steamer659 is online now  
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For the record- this one holds the Transatlantic Westbound Crossing since 8/73 at 34.97 knots average- the turbine nomograph has marks which indicated a SHP of about 137,000. One of the eight (can't remember which one) made over 39 knots after her conversion at Avondale in 86. The superheaters on these vessel are said to be notoriously fickle- but we take great care when raising steam from dead plant. New boiler automation and burners /burner controls- have solved most of the economizer and superheater problems- also new feed pumps were installed in the 80's- the largest Coffin Feed Pumps ever built. Our on hire speed is 27, regular transit speed 30, and maximum is limited to 130 RPM or 33.25... And yes, the boiler furnace bottom deck is a good ten to fifteen feet below the mud drum. Cheers...

Last edited by steamer659 : 26th November 2011 at 05:58.
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  #23  
Old 26th November 2011, 17:29
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Quote:
Originally Posted by Peter B View Post
The Sea-Land SL-7's are a legend at sea. I first heard of them in 1980 as I was an apprentice in Albert Maersk, a 40,000 shp steam turbine powered container vessel built at Blohm + Voss, Hamburg in 1975.

The question is; have more powerful merchant ships seen the light of day?
I think the answer is yes, as the Emma Maersk and her seven sisters have the potential of "feeding" the single propeller shaft with approx. 133,400 bhp, using the combined power of the main engine (~109,000 bhp) and the two electric shaft motors (9 MW (~12,240 bhp) each).
The problem is that the two measurements of power (Shaft Horesepower or SHP for turbines and Brake Horsepower or BHP for diesels) are not easy to compare. The price of oil has ensured that no more steam turbine powered merchant ships will be built, so the SL-7 SHP output will never be exceeded.
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Old 26th November 2011, 18:41
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The problem is that the two measurements of power (Shaft Horesepower or SHP for turbines and Brake Horsepower or BHP for diesels) are not easy to compare. The price of oil has ensured that no more steam turbine powered merchant ships will be built, so the SL-7 SHP output will never be exceeded.


Never say never. Researchers are working on "Nanorods" which they say enhances steam generation by allowing for easier steam bubble formation, to such an extent that only 10% as much energy may be required. Imagine the old Queen Mary at full tilt but burning only about 120 tons of oil a day instead of 1,200!

I'm guessing that would put an end to diesels as en economic proposition quickly.

This was published in Business Week magazine in the US at least 2 years ago. A lot of the technicals went over my head when I looked into it further, these were research scientists writing, but it seemed a matter of increasing surface area for heating using a surface of metal rods on a nano size scale jutting into the water. I don't imagine you could fit too many water molecules in between rods of such a size, their distance apart also being on that scale. Sort of like water tubes in a dense array in the firebox, but solid rods conducting heat on the water side instead, and on a much, much smaller scale.
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Old 26th November 2011, 19:21
Wallace Slough Wallace Slough is offline  
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The SL 7's were regular callers in San Francisco when Sea Land was operating them. As noted, they were twin screw steamers with very high horsepower. What has not been noted is that they were single rudder. Their Captains thought they were very good handling ships, but this was not true at the lower speeds required in harbors. Making the entrance across the Oakland Bar Channel into Oakland Outer Harbor was very difficult with these ships. Speed had to be kept quite low due to interaction with moored vessels. We would make up a tug on the transom to act as a rudder if required. The ebb current runs across the entrance to Oakland at speeds up to 3 knots and it was necessary to reduce the ship's speed to about 6 knots due to interaction. The pilot would hold the ship angled up into the current as she transited the Bar Channel. As the vessel neared the turn into Outer Harbor, hard left rudder would be ordered and the port propellor stopped to give additional drag. If necessary, the tug on the transom could come hard right and full ahead to provide additional lift. If the turn was started too early, the ship would ground outside of the channel. If the turn was started too late, she'd hit the corner of PCT.

Twin screw ships with single rudders are notoriously poor handling ships. The thrust from the propellors doesn't hit the rudder like it does with a single screw ship. Naval vessels and tugs normally have twin rudders placed behind the propellors which result in a very good handling ship.

Last edited by Wallace Slough : 26th November 2011 at 23:33.
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