Ore Bulk Oil Carriers

stores
7th March 2012, 01:58
Hello, Can Someone Please Explain To Me How A Obo Functions, ? The Method Of Carrying 2 Very Different Cargoes, I Allways Understood Oil Was Carried In Tanks, And Ore In A Hold, Surely Oil Must Be In A Airtight Compartment, How Were The Cargo Spaces Cleaned Between Cargoes, And How Is Ore Discharged, Thanks, Stores.

vasco
7th March 2012, 02:05
In a nutshell.
The oil is carried in the holds, which are cleaned manually.

Heating coils are then connected (they were stowed at the top of the hatch I think).

The hatches are batttened down and you have a tanker.

It has been a long time since I sailed on these and really had little to do with the preparation/changeover. I am sure there are others here who can and will explain in more detail.

This little snippet is just to satisfy your initial curiosity.

Erimus
7th March 2012, 11:04
One of the best definitions can be found on the following website....

http://www.globalsecurity.org/military/systems/ship/obo.htm

There are not so many of them around these days....remember the 'Derbyshire' was an OBO...............

rgds

geoff

stores
7th March 2012, 11:59
great, thanks for that,

John Cassels
7th March 2012, 19:38
I would gladly reply to you stores , but have spent more than 30 years
trying to forget about OBO's and have still not succeeded.

Erimus
7th March 2012, 21:06
I would gladly reply to you stores , but have spent more than 30 years
trying to forget about OBO's and have still not succeeded.

John..you are probably one of many I'm afraid....

rgds

geoff

Andrew Craig-Bennett
12th March 2012, 11:43
Heigh ho...

The OBO was a Norwegian invention, see here:

http://en.wikipedia.org/wiki/Ore-bulk-oil_carrier

Not to be confused with the ore / oil carrier ("O/O") which is an entirely different beast, stucturally, having small centre holds and big wing tanks. An O/B/O is, structurally, a bulk carrier.

The Big Idea is to cut down on time spent in ballast by being able to carry a wider range of cargoes.

The problems with the OBO concept in practice are these:

1. BIG PROBLEM: The pattern of world trade is such that the OBO simply does not work, commercially. There are very very few places that import oil and export coal, for example. Consequently the owner finds that he has spent a lot of money building an expensive bulk carrier or an expensive tanker. Instead of switching between wet and dry cargoes every voyage, as Naess intended, most O/B/Os trade for a year or two "wet" and then a few years "dry".

2. As everyone who has ever had to do with them will attest, these ships involve a lot of very hard, very dirty, work (some use the word "nightmare").

3. These ships are very unpopular with the oil companies, and indeed are banned from some terminals.

4. There is a specific safety issue. Conventional bulk carriers have their bulkheads mounted on stools which connect to the tank top. This is necessary because the bulkheads are corrugated to give the necessary strength. The stool is a void space, but if a crack should develop (as is not unknown) in the stool it can part fill with cargo oil leaving an explosive atmosphere in the stool space... this has never really been solved.

Varley
12th March 2012, 13:09
Andrew,

The Gotaverken built Seateam OBOs were exemplars of the stool cracking (my first trip as E/O was on one, "Norvegia Team").

Long after the last one had left Denholm's I visited "Trader" in Dunkirk. Close by one of the ex-Seateam OBO's tied up - the full length of every accommodation walkway had gas bottles lashed to the handrails. No need to ask what repairs were in hand (out of hand?).

David V

Andrew Craig-Bennett
12th March 2012, 13:44
The high water mark of O/B/O enthusiasm was reached with the series of nine PROBOS contracted by a complex syndicate of mainly Norwegian owners with Hynudai (three) and Korea Shipbuilding and Engineering (six) in the early 1980's.

These ships would in theory do just about anything from carrying bulk liquid caustic soda (s.g. 1.5 from memory) to carrying clean and dirty oil products to forest products and containers, and furthermore as designed they were meant to do this with a crew of, iirc, 14.

Unlike "normal" O/B/Os they had not side rolling split hatchcovers but massive pontoon covers handled by the two gantry cranes...this had an amusing moment when a US pilot could not find the ship as he was looking for a tanker not a geared bulk carrier...

Things did not go entirely according to plan...(Cloud)

I had altogether too much to do with the Probo Baro and the Probo Baoning.

The Probo Baoning after changing hands some years later achieved notoriety as the Probo Koala in the Trafigura waste dumping case.

randcmackenzie
13th March 2012, 00:53
Heigh ho...

The OBO was a Norwegian invention, see here:

http://en.wikipedia.org/wiki/Ore-bulk-oil_carrier

Not to be confused with the ore / oil carrier ("O/O") which is an entirely different beast, stucturally, having small centre holds and big wing tanks. An O/B/O is, structurally, a bulk carrier.

The Big Idea is to cut down on time spent in ballast by being able to carry a wider range of cargoes.

The problems with the OBO concept in practice are these:

1. BIG PROBLEM: The pattern of world trade is such that the OBO simply does not work, commercially. There are very very few places that import oil and export coal, for example. Consequently the owner finds that he has spent a lot of money building an expensive bulk carrier or an expensive tanker. Instead of switching between wet and dry cargoes every voyage, as Naess intended, most O/B/Os trade for a year or two "wet" and then a few years "dry".

Hello Andrew .You were a broker, and may know better, but it wasn't entirely true:

North Europe to USA with residual fuel oil, and return with coal, grain or fertiliser,

Oil cargo to Chile, ore out,

Low Sulphur Waxy Residue from Indonesia to USWC, then coal Vancouver to Japan/Korea, and round again,

Oil PG to Australia, coal or ore out to Europe, load North Sea or Africa and on you go.

2. As everyone who has ever had to do with them will attest, these ships involve a lot of very hard, very dirty, work (some use the word "nightmare").

Agreed - especially the older ones, though it did get much better. I did several years in them, and actually quite enjoyed it - hard core crazy maybe

3. These ships are very unpopular with the oil companies, and indeed are banned from some terminals.

An OBO from dry was always a bit hard to fix on a poor market, but in oil they were better tankers than the real thing, in that they could discharge the entire cargo with miniscule ROBs.

4. There is a specific safety issue. Conventional bulk carriers have their bulkheads mounted on stools which connect to the tank top. This is necessary because the bulkheads are corrugated to give the necessary strength. The stool is a void space, but if a crack should develop (as is not unknown) in the stool it can part fill with cargo oil leaving an explosive atmosphere in the stool space... this has never really been solved.

A problem in some, but in the main could be designed out - there was always a hrd spot where stool and hopper tank met. More likely to be a case of knocked off manhole bolts or stool plugs.

Best Regards.

stores
13th March 2012, 02:02
[/COLOR]Am glad i never sailed on one, i am not a ship designer or structural analyst, have allways said ships are too big now, size cannot keep increasing, rivetted ships appeared much stronger, welded hulls appear thinner,i dont think anyone now who designs ships really appreciates the stresses and strains imposed on a ship at sea, the bigger the ship the more stress, and with the massive tonnage of a cargo it carries welded steel does not seem to be strong enough, i saw avideo of a large container ship in heavy weather, a view from aft to fwd along center of main deck, have never seen a ship bend so much, was beyond belief, same as cruise liners now, too big, the criteria today seems to be one of huge ships and cargoes, minute crews to man them, at the expense of ship and human safety, it seems all the lessons and experience learned over time in ship safety and design have been forgotten, the Derbyshire was a classic example.(Scribe)

Andrew Craig-Bennett
13th March 2012, 12:48
Randmackenzie - I was never a broker; I rejoiced in the magnificent title of Tonnage Manager i.e. the person responsible for making sure we had the right ships and that they made money, by building, buying, chartering in and out and selling. Point being - I saw all the numbers, which a broker does not.

I do take your point that sometimes - just sometimes - these cargo combinations do work out, but by and large they don't, which is why these ships never became popular with owners and are now vanishing from the scene.

As an owner, you end up with a more expensive tanker or more expensive bulker and insufficient opportunity to make the money back.

I was responsible for a Capesize bulker that had honest to goodness hatch cleaning arrangements, in the manner of an O/B/O, with guns that self stowed and big eductors off the hatboxes, so we ran grain clean between cargoes, and that did work (and is still working, I believe) so a little bit of the O/B/O concept stayed with me.

Stores - remember that a container ship does not really have a deck, to speak of.

chadburn
13th March 2012, 14:16
Andrew, I have read your wiki article and am suprised that it does not mention the earlier vessel's that were capable of a dual cargo role, the vessel's concerned were built at the Craig, Taylor Yard on the Tees ( where my Paternal Grandfather was a Director). These vessel's 9 in all and the last one built in 1906 were built on Oil Tanker "lines", however, if required they could be used to carry dry cargo. One of the vessel's name's was the "Petrolea" and she was capable of discharging 3,500 tns of oil in 24hrs and be away in 24hrs. Sailing on an OBO was a challenge at the best of times, but the "facilities" on board were a world away from those on the old style Tramps.

Satanic Mechanic
13th March 2012, 14:36
If you want to see a truly mental ship then you should go and have a look into the vessel that started life as the LNG/C El Paso Cove Point and eventually became the STL type FSO Apollo Spirit - but in between it got converted to a OBO called the Jade Phoenix(EEK)


This sort of thing should really not be allowed in a sane and caring society.

Malky Glaister
13th March 2012, 16:08
I ended up having considerable experience on O B Os including three new buildings.
The concept was good however no one seemed whether to but bulk carrier men on or tanker men on the new type of vessels with sometimes dire consequences and some times amusing ones also.
We had folk who could not open hatches and others sucking them in or blowing them some feet in the air.
Other chaps new nothing of the instrumentation and other remote control gear fitted. Engineers didn't either!. One chap got a much better vacuum with tank vents shut but after the alotted time the tank must be empty. End result laying against Ras Tanura sea island at an alarming angle. Fortunately the vessel was brand new and therefore quite strong. I was 4th Engineer taking bunkers so it was thought that I had caused the problem. The Ship was FULLER ballast.
Another nightmare was an idiot on the bridge watch complaining about inert gas oxygen content being way to high with black smoke pouring out of the funnel. This is a cracker, it was found out much later on by an exasperated Chief he was measuring the oxygen content of the control air pressure gauge marked as IG pressure.
On older vessels well they were just plain dangerous and I was glad to get off them altogether at the expense of a job though as redundency from Denholms came with the collapse of CAST.
O B Os good concept but!!!

regards

Malky

John Cassels
14th March 2012, 20:28
OBO's , an abberation to all mankind.

Almost as if they were invented in Tokyo as payback .

And Andrew , having said the above , I know of lots of OBO.s which made
piles of money for their owners over many years.

PMN1
30th April 2012, 23:00
Not to be confused with the ore / oil carrier ("O/O") which is an entirely different beast, stucturally, having small centre holds and big wing tanks.

How much volume did they loose compared to an equivalent size only dry or only liquid cargo ship?

stevekelly10
1st May 2012, 00:02
I had the misfortune of sailing on one once and it was not an experience I ever want to repeat! It was my first trip with Shell as 3/E on the Rapana, a V.L.O.O as Shell called it. The trip got off to the worst of starts possible as I was sat on the jetty at Tubarao, waiting for them to lower the gangway so I could get onboard. They where having problems lowering the gangway as the two pieces of the telescopic ladders became jammed with iron ore dust. The mate and the chief engineer were in the process of freeing it, when it suddenly freed itself due to the strain it was under. Unfortunately it caught both men trapping them by the feet, their screams turned my legs to jelly! once freed they had to be rushed to hospital as both had suffered nearly complete amputations of one foot each.
The trip never got any better, ship was a disgrace. fortunately it only carried iron ore on my time onboard as I said that if they loaded it with oil. I would not sail out of port on it and would be sat on my suitcase waving goodbye to them!
Later events proved me right! after a long drydocking the Rapana loaded oil again and had just discharged the first part of her cargo at Brofjorden and was on her way to Tranmere when she suffered a pumproom explosion and fire killing 3 of the crew. Shell sold her and her sister ship shortly afterwards! A lesson learnt the hardest of ways!

Andrew Craig-Bennett
4th May 2012, 12:47
How much volume did they loose compared to an equivalent size only dry or only liquid cargo ship?

Esentially none, in liquid, unless one counts in the lost deadweight that would have been available had the ore holds not been built as such. In practical terms, none.

In dry, an awful lot, as they were built around the s/f of iron ore, 0.74 or thereabouts.

I can remember when I had to tell junior officers who had to do with Shell expediters "Don't mention the RAPANA" in much the same terms as "Don't mention the War!"

PMN1
5th May 2012, 09:25
1. BIG PROBLEM: The pattern of world trade is such that the OBO simply does not work, commercially. There are very very few places that import oil and export coal, for example. Consequently the owner finds that he has spent a lot of money building an expensive bulk carrier or an expensive tanker. Instead of switching between wet and dry cargoes every voyage, as Naess intended, most O/B/Os trade for a year or two "wet" and then a few years "dry".

.

I've seen pictures of Ore-Bulk-Container ships, namely the Cast ships with alternate Ore/Bulk and Container holds, do they work commercially and are OBC's usually like this with alternate holds or are some with holds that can hold all three types?

I've also seen references to Bulk carrier/Car-Carriers with demountable suspended car deck but i'm not sure if that was just a suggestion rather than an actual ship.

John Cassels
5th May 2012, 09:44
These were the conbulkers , not OBO's .

They were a great commercial sucess , ran them for years.

muldonaich
5th May 2012, 12:50
would agree with you there john also carried general cargo in the bulk holds they must have made cast a lot of money over the years brgds kev.

A.D.FROST
6th May 2012, 10:18
I've seen pictures of Ore-Bulk-Container ships, namely the Cast ships with alternate Ore/Bulk and Container holds, do they work commercially and are OBC's usually like this with alternate holds or are some with holds that can hold all three types?

I've also seen references to Bulk carrier/Car-Carriers with demountable suspended car deck but i'm not sure if that was just a suggestion rather than an actual ship.

Bulk Carriers with car decks were a popular type of BC (Buries Marks,Bibby etc.)some chartered to car makers such as Volkswagen etc.and some companies with PCC now such as O.W.before Pure Car carriers took over the trade,it was another way of reducing ballast trips with guarantee cargoeshttp://www.photoship.co.uk/JAlbum%20Ships/Old%20Ships%20C/slides/Cheshire-05.html

Gulpers
6th May 2012, 11:48
PMN1,

I'm not wanting to stray too far from the thread's OBO subject, however, J&J Denholm had four car/bulk carriers during the 70's.
These ships are certainly well remembered by all who sailed on them but, to be fair, not everyone remembers them with affection! We tended to work hard, and play hard, on the Trolls - particularly when carrying cars.
The ships were ARCTIC TROLL, TROLL RIVER, TROLL PARK and TROLL LAKE. They crop up in a few threads and there is a dedicated discussion about them here (https://www.shipsnostalgia.com/showthread.php?t=7360&highlight=Troll+boats).

There are also plenty of photographs amongst this (https://www.shipsnostalgia.com/gallery/search.php?searchid=1154290&cpage=1) selection from our Gallery. (Thumb)

Andrew Craig-Bennett
6th May 2012, 12:12
and then of course there were the Last Word in OBOs, the PROBOS, which could carry:

- Liquid Caustic soda, SG 1.6
- Oil and oil products
- IMO 2 liquid chemicals
- Dry bulk
- Steel products
- Forest products
- Ores in alternate holds
- Containers

all with a crew of 11 Norwegians .

Allegedly.

(this was never tried in practice - we just about got by with ten Brits and 12 Filipinos).

What could possibly go wrong?

Mention of the PROBO BARO and the PROBO BAONING still makes me want to scream "AAAAAARRGGHH", then go and curl up in a little ball in a corner and clutch my teddy bear.

Long after I had ceased to have anything to do with her, the PROBO BAONING, sold and renamed PROBO KOALA, was the ship at the centre of the Trafigura toxic waste dumping scandal.

No, I do not like OBOs. Not even slightly.

Erimus
6th May 2012, 17:28
You're not sitting on the fence then Andrew!

rgds

geoff

Andrew Craig-Bennett
6th May 2012, 18:45
Been there, done that thing, got the boilersuit wore it out crawling down the duct keel and got holes in it from caustic soda not retained by the oversize nitrile hatch seals. And did I mention No-Control? And why we had to fit the world's biggest Becker rudders because the brutes steered like a car with horrendous oversteer on a skid pan? And when we had fixed all those little issues, it was amazing how many things those ships could do - and all of them badly!

John Cassels
6th May 2012, 19:22
How can you get caustic soda in a duct keel caused by hatch seals ?.

Malky Glaister
6th May 2012, 20:11
John,

You got lots of strange things down duct keels and from Lord knows where.
Dangerous places, I doubt I will ever go down and along one ever again.
A 7 OBO vet
regards |Malky

randcmackenzie
6th May 2012, 23:26
Me neither Malky, and I'm not one bit sorry. I'm a veteran of 8, but I was brave enough to do some of them several times.

Burmah Garnet (O/O) (In oil only)
Nordic Chieftain/Cast Heron/Helm (OBO) Oil/ore/coal/mobile homes!
Scandia Team (OBO) oil/ore/coal
London Team (OBO) coal/oil/ore
Friendly Ranger (OBO) Coal/oil
Friendly Carrier (OBO) Coal/ore/oil/animal feed
Stride (OBO) clean oil/black oil/ore/coal/fertiliser
Muirfield (OBO) in ore only - mercifully.

The mobile homes was a one off, but most of the other cargoes were more than once.

Malky Glaister
7th May 2012, 01:47
I was on Cast Heron when she became Helm. We loaded tapioca in Thailand for Rotterdam. That was some cargo, weeks to load, covered in dust (everywhere and every thing) Last ship with Denholms, redundant Jun Chief Engineer. Well peed off, I binned all my Denholm News mags (regrettably)

oh well

regards

Malky

oldman 80
9th May 2012, 13:17
I was what you would classify as a definite OBO man. My first experience of them was standing by the building of Norvegia team and Anglia Team in Gothenburg in the early 1970's. It was the perfect learn about OBO's experience. I sailed in Anglia Team as 2/0 on her maiden voyage. From that time forward I seldom got away from them sailing in several as Chief Mate then Master.
They were demanding on personnel - to say the least. They could almost drive you to the point of insanity due to persistent structural fracturing and the resultant inevitable contamination of ballast water. Very hard working ships, and contrary to what most people might think, it was the change over from coal back to oil which created most headaches especially if the cleaning of the holds after the last oil cargo had been not as good as desired.
On iron ore, (a high density cargo) they were subjected to extremely high stresses (particularly sheer forces) due to the practise of alternate hold loading. ie cargo in holds 1, 3, 5, 7 & 9 with 2, 4, 6, and 8 empty.
eg 10,000 tonnes in #1 Nil in #2 and 10000 tonnes in No 3. The sheer forces at the bulkheads between 1 and 2, and between 2 and 3 were always cause for concern, especially in heavy weather. Same story with the other holds.
The bulkhead at the aft end of No.9 separating the cargo spaces from machinery spaces was always the one which caused the greatest concern - for some reason the maximum permissable stresses at that point were generally a good bit less than elsewhere along the vessels length.
If an OBO was going to snap- that's most likely where it would happen, and I would suggest the consequences would have been extremely severe and quite sudden. The accomodation, bridge and machinery spaces would probably just roll over, and go straight to the bottom.
Free surface was also something which had to be watched like a hawk, - no more than 3 slack holds at one time. Break that rule and she'd loll very badly, - and very quickly. (Maybe worse, if action was not taken immediately)
Nobody was ever paid enough on those ships - long, long hours involved there.
The ones I served on continually alternated between wet and dry cargo pretty well every voyage, - which was just as well, as when that did not happen then the gear would play up terribly if it wasn't used regularly. e.g. do two or three consecutive voyages on oil, and oh boy, would you have trouble with the hatches after that, - they wouldn't want to open at all.
In the case of the reciprocal ie two or three voyages on dry cargo, then you could be sure the cargo valves would give heaps of problems when going back to oil, - mostly down the duct keel, a terrible place to work even under the best of circumstances.
Heating Coils for liquid cargoes were kept under the hatch covers,( being lowered to the bottom of the holds and connected up when required, then raised again afterwards,) on the 1st generation of OBO, but by the time of the second Generation they were built into the bulkhead stools and under the tank tops within the double bottoms.
Grab damages when discharging dry cargo created enormous problems as well, puncturing the hopper sides and tank tops on far too many occasions. Not desireable at all when you were going to load oil a few days later.
You definately required good welders on those ships - they'd soon grind to a halt if not.

John Cassels
9th May 2012, 20:01
But , nobody forced you to load alternate holds !.

oldman 80
9th May 2012, 23:33
Well I suppose you could say that, but with iron ore, alternate hold loading was recommended,or imposed on the vessel, in the builders operations manuals.
The reason of course was to minimise metacentric height/maximise KG which would have been incredibly excessive if iron ore/high density cargo was loaded in all compartments. ie small amounts in each hold. Better larger amounts in alternate holds.

oldman 80
10th May 2012, 00:26
Oh, I nearly forgot :-
Holds 1,3, 5, 7 & 9 were strengthened for high density cargoes whilst 2, 4, 6 & 8 were not.
Ref:- tank top loadings.
I'd almost forgotten, but on ore, in the case of most OBO's I served on - Alternate hold loading was actually a condition of class, so we were forced to do it that way after all.

RLD
17th October 2017, 13:00
It's a good job OBO's are finished. No more crawling in the pipe tunnel, virtually swimming in crude oil. At least we had a change from oil when we got a coal cargo, or even a grain cargo. It meant a lot of tank washing though.

LTS
19th October 2017, 00:04
I was on Cast Heron when she became Helm. We loaded tapioca in Thailand for Rotterdam. That was some cargo, weeks to load, covered in dust (everywhere and every thing) Last ship with Denholms, redundant Jun Chief Engineer. Well peed off, I binned all my Denholm News mags (regrettably)

oh well

regards

Malky

Loaded tapioca in Kohsichang on the Nordic Sky.
Thankfully the wife wasn't onboard.

RLD
19th October 2017, 10:33
I was Mate on the Helm a couple of times. The worst ship I was ever on in Denholms. I spent most of my time in the pipe tunnel operating the valves from there during discharge because that was the only way they would work - manually! In fact, that's when I threatened to walk off if they didn't send a team to work on the valve system. Luckily (or unluckily) they did, so I stayed on. Several years later, when the Turks bought her, she was renamed Inci-S, and I was sent to her as a consultant because the Turks couldn't manage her. She's a ship I'll never forget. Bob Dewick:

Ian Lawson
19th October 2017, 14:50
Loaded Tapioca in Ko Sichang a couple of times with Amsterdam as the disport. This cargo is liable to spontaneous combustion.

RLD
19th October 2017, 15:39
Most of the cargoes we loaded on the Helm were either crude oil or iron ore. I remember having to get the crew to remove about half a ton of fine iron ore from the pipe tunnel after there was a massive leak from the hold through a tank valve. It wasn't only oil that leaked into the tunnel! I reckon OBO's produced many more problems than straight tankers did.