sulis
Coastal Cruiser
Posts: 201
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Post by sulis on Mar 21, 2009 21:32:00 GMT 1
Bunkering is big business in Falmouth. Everytime I go out there are ships in the Bay or the Roads waiting to be refuelled. So a question for the experts...... How much fuel can ships carry?What is their typical range? Some of the vessels must be capable of trans Pacific. Watching them as I do and did with this mornings photo, I just wonder how much fuel oil they take on and what it costs?
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Post by oldsalt on Mar 22, 2009 1:50:30 GMT 1
Well it is in tons not gals. ;D Typically for a turbine engined ship with three boilers it is classed as bunker A,B, or C as to the quality, A being the best. this is a heavy oil that has to be heated before it can be burnt in the boiler. The less oil burnt per watch the happier the chef engineer (A chap we called "Belfast Smith") would be and as I was 4th on a few trips and it was my job to present the daily engine room log to him if the oil figures where the ship mils where better than the engine miles then I would get a tot from him to celebrate a nice way to start our mid day meal and I would be invited to sit at his table. It was his way to put one over the old man (Ships Captain) Every one then knew the job (the Ship) was running well. A typical 6,000 to 10,000 toner with three boilers as was my experience in the early 1960s will carry about 500 to 800 tons in tanks that can be filed with oil or water ballast if required this is transfered to port and starboard day or duty tanks then to be fed to the boiler burner system and the three boilers will burn 3 to 4 tons per 4hr watch = 24 tons approx per day with a 25 day range = 600ton.
Diesel engined ships use a finer grade which is a lighter oil and will atomise in the injector at a lower temperature with out heating it before it is used, again it is it tons as to gals. Having not sailed on Motor jobs I don't have any experience of them. May be Nigel will be able to give some more precise comments from his experience in the merchant Navy and now in the heavy fuel business.
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Post by NigeL on Mar 22, 2009 9:30:04 GMT 1
Well it is in tons not gals. ;D Typically for a turbine engined ship with three boilers it is classed as bunker A,B, or C as to the quality, A being the best. this is a heavy oil that has to be heated before it can be burnt in the boiler. The less oil burnt per watch the happier the chef engineer (A chap we called "Belfast Smith") would be and as I was 4th on a few trips and it was my job to present the daily engine room log to him if the oil figures where the ship mils where better than the engine miles then I would get a tot from him to celebrate a nice way to start our mid day meal and I would be invited to sit at his table. It was his way to put one over the old man (Ships Captain) Every one then knew the job (the Ship) was running well. A typical 6,000 to 10,000 toner with three boilers as was my experience in the early 1960s will carry about 500 to 800 tons in tanks that can be filed with oil or water ballast if required this is transfered to port and starboard day or duty tanks then to be fed to the boiler burner system and the three boilers will burn 3 to 4 tons per 4hr watch = 24 tons approx per day with a 25 day range = 600ton. Diesel engined ships use a finer grade which is a lighter oil and will atomise in the injector at a lower temperature with out heating it before it is used, again it is it tons as to gals. Having not sailed on Motor jobs I don't have any experience of them. May be Nigel will be able to give some more precise comments from his experience in the merchant Navy and now in the heavy fuel business. Fraid those days are long gone and very few if any ships are steamers now. My last steamer burnt ~400 Tons per day at cruise speed ... she was 440,000 Tonner ! Average supertanker in my steam days of 200,000 Ton would be looking at ~ 200 tons per day bunker consumption without tank cleaning / ops. Speed 14.5 - 15kts. Even the advent of Super Heat Turbines etc. didn't reduce consumption enough. Average bunker intake per refuel - about 8000 - 9500 tons.... more if it was Europe / USA to Gulf and return without bunkering. Later as fuel prices rose shipping companys couldn't afford the luxury of the steamer anymore and the shaky Motor Ship took over. These gave immediate ease to the Company pocket in cutting steaming fuel cost dramatically and used SAME fuel and SAME heating idea. Typical ... steamer burning about 100 tons a day ... motor ship burning 30 tons a day for same speed. Funny thing is that bunker tanks didn't significantly reduced in size as a result ! Fuel - forget A,B,C as in the old days ... only old hands talk in those terms now. We have LFO, IFO and HFO ... with the last one HSRFO. Light Fuel Oil - which is the crossover from diesel to Fuel Oil and is more like a heavy diesel - commonly termed MDO. IFO is Intermediate Fuel Oil, of a medium grade and low sediments etc. - it's used in higher revving "action" stuff such as military of big generators. HFO is in two forms Cracked or Straight Run .. (cracked has had all light fractions removed by Vacuum Cracking and is basically at the end of refining cycle - any lower in the chain and it's bitumen grades ! Straight Run is a sought after Heavy Fuel Oil as traders buy it, Vacuum Crack it to gain further light fractions from it and then sell on the "Cracked" to users, gaining light frractions for blending etc.). The HFO is the one that ships use generally whether Steam or Motor. For those that cannot see an engine running on that stuff - it is highly heated and is for when engine is set on passage and basically stays at that speed for days / weeks on end. For manouevring - the engineers switch the engine over to MDO - the LFO version to allow engine to stop / start and alter speed. So there you are ... for better info on Bunker capacity of ships - Mirelle I'm sure will be along soon .. I will look in some of the files and see if I can drag out some data ...
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Post by NigeL on Mar 22, 2009 9:39:23 GMT 1
Sorry I left out HSRFO ... this falls into two categories as well.
It is High Sulphur Residual Fuel Oil. This is a base Fuel Oil that has been opld style refinery produced with hydro / vacuum cracking. Seldom seen now as refinerys produce more fractions. It's two sub categories are similar to HFO in Long Residue (un'cracked) and Cracked. We do not normally refer to HSRFO as Straight Run as that applies to the better quality HFO.
There are loads of company names as well that add to the list - but the above are the basic steps in the Fuel Oil chain. Note that regularly development of greater extraction of fractions occurs - so the goal posts do move !
One development that has happened is the "Heating Oil" fraction. One of the cracked fractions from Straight Run is a heavy diesel like fuel. It can be burnt as MDO or blended into Industrial Diesel (Red / Agricultural) ... we had loads of it last year for blending. This year seems it's out of favour. (Secretly - I'm glad - it's jet black, after only a few days a white opaque plastic sample bottle is stained dark brown ... it drops out fine sediment .... UGH !! - BUT I never told you that !! )
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Post by ood on Mar 22, 2009 21:37:45 GMT 1
OK, there is a lot of water coming out the 'anchor lead holes' in the bow. Maybe I should know why but I don't, is there more than one reason. It sure not the crew with buckets........
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Post by oldsalt on Mar 23, 2009 0:22:20 GMT 1
Thanks Nigel I thought you would have an up to date answer. Wow how things have changed.
Now what can we attribute the watery Question to. My thoughts are water on the fore deck and its just running off down the Hawsepipes or they are preparing to wash off the chains.
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sulis
Coastal Cruiser
Posts: 201
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Post by sulis on Mar 23, 2009 6:54:23 GMT 1
I'm used to fuel in tons, or rather tonnes from my Flying days. Max load on a 747-400 about 175tonnes--SG around 0.8
As to the water,you often see the ships here like that, usually when weighing anchor but not always.
So what's the likely capacity of the ship in the photo and its consumption?
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Post by NigeL on Mar 23, 2009 9:55:29 GMT 1
[quote[ OK, there is a lot of water coming out the 'anchor lead holes' in the bow. Maybe I should know why but I don't, is there more than one reason.
It sure not the crew with buckets........ [/quote]
The fire main will be pressurised during any fuel transfer and the way to relieve over-pressure is to open the 'cable-washer valves' on the foc'sle. They are high pressure outlets around the anchor chain inside the hawse-pipe to clean the chain as it comes back on board. "The Term is 'Water on deck' ".
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Post by NigeL on Mar 23, 2009 10:16:17 GMT 1
I'm used to fuel in tons, or rather tonnes from my Flying days. Max load on a 747-400 about 175tonnes--SG around 0.8 As to the water,you often see the ships here like that, usually when weighing anchor but not always. So what's the likely capacity of the ship in the photo and its consumption? I would hazard a guess that the bunkering vessel is possibly about 2 - 3KT size ... most likely 3KT. Guessing sizes of ships is hard when they are Bulkers / Tankers as width / depth increases more than length with size due to structural stresses. This ship I would guess is somewhere between 30 and 50KT. 'Sulis' - give me the name of the Ship and I can tell you ... but I cannot make it out from the linked photo ... I would guess she would have bunker capacity ... this is a real guess ! about 1700 tons. I really need Mirelle to come in here as he runs various Bulkers ....
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Post by NigeL on Mar 23, 2009 10:31:19 GMT 1
For peoples interest ....
Over the years various companys like Sulzer, B&W, MAN have played with alternative fuels. One that was talked about in the 80's and hailed as possible candidate was Coal Slurry. Pulverized coal carried in a fluid medium to burn in either steamers or motors. later of course emmissions were looked into and it failed dismally - plus of course the maintenance aspects to keep systems running on such a product.
With Liner trade and high speeds - IFO became a regular fuel but it's pricing started to hurt Shipping Co's ... so engines were looked at for better more efficient running. CO emmissions again came in to play. Non-Liner ships carried on with HFO and better burn rates - even to cutting speed from some at 15+ kts down to 14 .. 14.5 kts ... it may not sound much - but it is significant to large vessels.
Mireele will know more about this than I - but Container vessels like Atlantic Conveyor and Bay Class were originally fitted with gas Turbine engines similar to Concordes. Idea was to have 'pseudo- aircraft carriers' part funded by US Navy, MOD. They were fast - in fact at one time the real flat out speed was literally classified. But horrendous fuel bills even on container service. The maintenance costs as well were out of this world. They required high quality Gasoil fuel more akin to Kero than diesel. It didn't take long for US Navy and MOD to pull the plug on them and if ships weren't scrapped - they had the engines pulled out and replaced with conventional 2 stroke low speed Heavy Fuel Diesels. Note even QE2 went from Steamer to Motor ship in her period .. to passengers it was not so good as ships vibration despite counter-balances etc. fitted - she suffered like all Motor Ships do.
Some vessels even went as railway Engines .. diesel-electric (actually QE2 was this) ..
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Post by mirelle on Mar 23, 2009 10:52:52 GMT 1
You rang? Most ships these days burn "heavy fuel oil" (HFO") with a viscosity of 380 centistokes (back to you, Nigel, to explain that one! ) The Sea-Land SL7's were gas turbine - 35 knots - Sea-Land Inc dumped them on the US Department of Defense pdq after the second oil shock! The Big Bays were a 3,300 teu design by Marshal Meek and Co at Blue Funnel Line for OCL - the same design was used by other lines - they were steamers and were re-engined in the late 80's. There was a fashion for running big boxboats on 600 seconds fuel which saved a little money but there were very few suppliers. Older generators ran on diesel oil but nowadays they also run on heavy fuel oil. My last steam VLCC was 166t/day - she was a "little one" of 226,000dwt. We had a big one but she was diesel - 56t/day. Both had about 33,00 hp going to the propeller. The containerships I run (diesel) can burn 256 t/day at flat chat which in their case is 25.5 knots fully laden. Almost all ships are designed for a range, without refuelling, of 20,000 miles at full away sea speed which customarily is 90% of the main engine's Maximum Continuous Rating. Now, a ship won't take on that quality of bunker oil because it is standard operating practice not to use the fuel that you have just taken on board until you have had a sample analysed - bad fuel can immobilise a ship and wreck the main engine and there is a lot of it about - so you draw from the old tank until you know the fuel in the new tank is OK. There is a samply cuff which fits over the bunker manfold coupling and takes a drip at a time from the fuel going through the coupling - usually the ship takes two samples and the supplier takes two all are sealed together and signed - the ship sends one off to the Class Society for analysis and keeps the other for use in the event of dispute. Working back from the 20,000 mile range will tell you what the ship's bunker oil capacity will be. Most tankers and bulkers these days make 14.5 knots laden at 90% MCR and a 50,000 tonner ought to leave you change from 20 tons a day. Container ships are much faster and passenger ships, whilst slower than containerships, are in a different league because they have huge aircon, etc demands and use medium speed engines, rather than crosshead slow speed engines, in order to save space. If you can, you will take bunkers at one of the places where fuel is cheap - Singapore, Rotterdam and Long Beach are the best places to buy fuel oil. Falmouth is a bit expensive really.
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Post by NigeL on Mar 23, 2009 11:06:10 GMT 1
There you go ... knew Mirelle would come up with better info than me ... I only inspect and analyse the cr*p !!
The only time I was really involved in ships consumption was in Shell when we had a Ships Performance sheet to fill in ... pain the rear ! and when on UK Coastal trade when I had to keep similar data ... and there the 1000 Ton Acid tankers were on about 3 to 4 tons a day .. basically we were tank-cleaning / pumping as well as steaming nearly every day ... doubling consumptions.
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sulis
Coastal Cruiser
Posts: 201
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Post by sulis on Mar 23, 2009 15:44:03 GMT 1
Thanks very much for the info, very interesting. Here's a close up of that ship.
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Post by mirelle on Mar 23, 2009 16:08:23 GMT 1
She's an Indian products tanker, built in 2000, about 40,000 dwt. (The Ship Spotter's Vademecum, courtesy of the French Government: www.equasis.org/EquasisWeb/authen/HomePage?fs=HomePage ) This size is sometimes called "handy size" as ships of this size, about 182 metres LOA and 32.2 metres beam with a laden draft of 11 or 12 metres, can get into most ports but can also undertake long international voyages reasonably economically. Most products tankers and most bulk carriers are this sort of size. Typical of the sort of ship that you may see bunkering in Falmouth.
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Post by NigeL on Mar 23, 2009 17:01:31 GMT 1
Yep - and goes to show how easy to mistake a bulker / tanker ... first photo is my excuse is not so clear ... I wasn't too far out with tonnage though.
As Mirelle says the size is handy as USA is seriously limited on ship size - you may be surprised to hear that unless you go to Canada - there are no real serious deep-water ports in US as in Europe etc. Big vessels have to lighter off to get in.
I worked on worlds biggest lightering operation for Chevron at Pascagoula ...
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Post by mirelle on Mar 23, 2009 18:18:54 GMT 1
What a nice big centreline hose handling crane!
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Post by NigeL on Mar 23, 2009 19:06:39 GMT 1
What a nice big centreline hose handling crane! Alright - don't rub it in !! I made mistake of taking the vapour piping above wing tanks as side opening hatch runners !! I only looked quick and forgot about the crane !
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Post by Candide on Mar 25, 2009 13:54:29 GMT 1
Thanks for the link, Mirelle. Haven't gone beyond home page yet but should be enlightening ( or debunkering ho ho)
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Post by Gandy on Apr 2, 2009 12:19:59 GMT 1
... One that was talked about in the 80's and hailed as possible candidate was Coal Slurry. Pulverized coal carried in a fluid medium to burn in either steamers or motors. I did some instrumentation work for a power station that ran on what they called "washery slurry". Waste from the pitheads from the days when coal was washed. Cost was around £1.50 per ton, but some of the stuff was virtually unburnable so they sometimes needed to mix in a little "real" coal and sometimes run an oil burner in the furnace.
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Post by jenku on Apr 2, 2009 13:13:31 GMT 1
Thanks very much for the info, very interesting. Here's a close up of that ship. Anchor chains look a bit confusing? Is that supposed to be a bahamian mooring? (I'm sure you will blame the tides as you usually do over there...)
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