Model Boat Mayhem
Mess Deck: General Section => Full Scale Ships => Topic started by: barryfoote on March 20, 2009, 08:30:34 am
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Just seen this on the BBC. Very interesting and I was wondering what everyone thought about it. Are these ships purpose built or converted for the purpose?
http://news.bbc.co.uk/2/hi/uk_news/wales/south_west/7952415.stm
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Purpose built - and you don't want a power cut!
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Very specialist build with liquified gas carried in stainless steel tanks insulated from hull. Imagine what would happen if the cargo leaked and contacted the hull in any quantity. Instant steel embrittlement and cracking. However, both LPG and LNG have been transported since the 60's into the UK in which time a lot of experience has been gained of the associated problems and there has (as far as I am aware) been no incident of significance to the environment.
Barry M
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Many years ago in the 1970's I worked on a project for Shell Research on the design of a machine that sprayed the inside of tanker hulls with a PU foam laminate for LPG carrying.
We built a tank on the tank farm at Stanlow which had the same cross-section as a tanker hull, and then sprayed the inside using our new machine. There were all sorts of temperature sensors and strain gauges buried in the PU foam. My involvement ended at that point, but I understand that they went on to spend another couple of years pumping Propane/Butane in and out of the tank to see how it held up.
At that time, they reckoned that they could save many millions on the cost of each vessel by using this method. Ships only had top be single skinned as opposed to double skinned as used previously. My understanding at the time that the new method would be used on new vessels only, but this has obviously extended to the conversion of new vessels?
Malc
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Do these LNG tankers use the boil off for main engine fuel whilst at sea?.......Derek
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Derek,
Some do - or certainly did - in the boilers but I believe that some now employ recompression and improved tank designs to hang on to the cargo as much as possible.
It was not unknown for some Ch/Eng using the former system to achieve impressively low boiler fuel consumptions. However, when the Mate queried the amount of cargo burned in the boilers, this brought on an attack of innocence and whistling while it was suggested that unusually high atmospheric temperatures had caused equally high levels of cargo boil-off. %) %) %)
Barry M
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Derek, That has been the traditional system but obviously every thing that can be done to avoid any waste is being pursued. Check out Wikepedia on the subject:
http://en.wikipedia.org/wiki/LNG_carrier
LNG Tankers have been around since the early 60's and I'm afraid people protesting about such things really do need to get themselves gainfully employed and do something usefull rather than get in the way of what technology is trying to do to make things better for everyone.
To me they might have a bit more credibility if they didn't use gas, electricity or drive cars around themselves but from what I can see they are no more than bored trouble causers.
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Didn't "Royston Grange" get incinerated after being hit by a Chinese gas carrier? OK, it was an early one and standards have improved....but the danger exists and it's down to the guy on the bridge to avoid hitting anything at all. BY.
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Hi Bryan
Was that hit from a gas cloud from a normal tanker or a gas tanker?
The Roystan hit a poorly dredged bit in the bottom of the channel and veered into the side I think of the tanker
1000 degree heat everybody still at there station it was so fast .
No damage below waterline but no oxygen
I lost friends there but long time ago
79 dead
Dave
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Didn't "Royston Grange" get incinerated after being hit by a Chinese gas carrier? OK, it was an early one and standards have improved....but the danger exists and it's down to the guy on the bridge to avoid hitting anything at all. BY.
Royston Grange was a 'freezer' - not a gas tanker - and the tanker which hit it was carrying crude. No LNG/LPG carrying vessel involved.
Barry M
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Sorry, old memory playing tricks again,
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In America, those ships, and other ships of their type are still very dangerous.
Apparently if you allow one into port, it will blow up. O0
Americans want cheap energy, but they don't want to
have it conveniently shipped and piped ashore... It blows up... %)
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Didn't "Royston Grange" get incinerated after being hit by a Chinese gas carrier? OK, it was an early one and standards have improved....but the danger exists and it's down to the guy on the bridge to avoid hitting anything at all. BY.
Royston Grange was a 'freezer' - not a gas tanker - and the tanker which hit it was carrying crude. No LNG/LPG carrying vessel involved.
Barry M
...and I should have said "reefer" instead of "freezer". The brain cell is getting worse. {:-{
Barry M
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The Royston Grange hit a products tanker, loaded with petrol. Her intakes for the air conditioning system pick up and suck in the released petrol vapour from the tankers evaporating cargo, this ignited the vapour inside the Grange. Very tragic accident as they found burnt skeletons on burnt out bunk springs, after the aciddent, the MCA issued a M notice advising ships to have fitted in their bridges crash stops for the ventilation and in event of a collision to immediately crash stop the system. As previously said all gas boats as well as chemical boats are specially designed for the cargo and have a good safety boat. I know of one which steamed between the Sunk Fort Towers in the Thames estuary, she completely demolished the Towers and survive with no loss of cargo. I have heard it said if a tanker did leak the sea around her would freeze for some considerable distance. The only real danger with them as with all gas transport systems and storage tanks is a blevy happening. if you see one run like hell, the bang is worse than a shedful of TNT going off.
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I'm guessing the "smoking lamp" is out?
Just to clarify the above post B.L.E.V.E. Boiling Liquid Expanding Vapor Cloud Explosion
http://www.youtube.com/watch?v=cb7V7kkCyz4&feature=related
and this:
http://www.youtube.com/watch?v=lJt7CkqGcS8
As a firefighter, this our worst nightmare!
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I worked in the Stavanger yard of Rosenberg Verft ,in the late 70's I think they were the first yard to design and build LNG carriers , they were built under their licence in other parts of the world. :-))
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they took it past somalia, yeeeeep
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I think you will find the first LNG boats were running up to Old Haven in the Thames in the late 1960's, I cannot remember thier names at the moment, but the childrens comic the Look and Learn had a cutaway drawing of one and I stopped having them by 1967/8.
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I think you will find the first LNG boats were running up to Old Haven in the Thames in the late 1960's, I cannot remember thier names at the moment, but the childrens comic the Look and Learn had a cutaway drawing of one and I stopped having them by 1967/8.
Methane Princess and Progress use to run to Canvey Island
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Thanks Capt Jack they where the two I was thinking of, I believe they used to run from Libya.
David
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Brain cell cranking into life - wasn't there a Methane Pioneer which just pre-dated the Princess and Progress?
Barry M
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Here's one on the Manchester Ship canal