loading a ship

[Tony Wilding]

I did not realise loading a large bulk carrier was such a complicated task, so as to lessen hull stress, was suprised just how much movement there is in the hull. were the ships of our days 10,000 ton freighters the same. no wonder these big ones crack.

[Ivan Cloherty]

I did not realise loading a large bulk carrier was such a complicated task, so as to lessen hull stress, was suprised just how much movement there is in the hull. were the ships of our days 10,000 ton freighters the same. no wonder these big ones crack.

Short answer Tony is yes, no matter how big the ship, even the smallest coasters, load them wrong you can break them, but naturally the bigger the ship the bigger the problem, but it's not only the stresses brought into the hull you have to consider, load them wrong and sail you may not reach the other side, not because of the stress factor but because the vessel will not react in a sea condition in the way that she's supposed to and could founder because she doesn't rise to the next wave.

I think there may be more technical reasons coming along on the following waves!!!!!!!!!!!!

[j.sabourn]

Tony it was much more complicated loading a 10000 ton conventional ship than what it is loading a moden bulk carrier which is literally a piece of p...ss in comparison. Every type of grain has a different stowage factor, and as grain like water has a free surface moment there are certain rules and regulations stipulating the mininum GM etc. as regards stability, in other words without going into great detail the holds have to be more or less full otherwise feeder boxes have to be fitted. to supposedly feed the lower holds when they become slack. Bulk carriers due to their design this problem is mostly unneccessary, in rare occasions it maybe one has to bag off on top of a partially filled hold, this however is expensive and is usually avoidable. Apart from feeder boxes on the conventional ships, shifting boards also have to be fitted dividing the hold longitudally going down to a certain depth a headache fitting out a ship to load grain especially when you had 5 or 6 different types and werent told the exact stowage factors until the last minute. Stability wise especially in Canada and the states you had to prove to the surveyor mathematically that the vessel would have a minimum I beleive positive GM throughout the voyage of about 6 inches with burnout of fuel etc. As regard sheering and other stresses you mention the bulk carriers I was on all had loadicators which when you put in the approx weights gave you a reading within seconds, something you never had on old cargo vessels. Everything on the old vessels had to be worked out the hard way. Most bulk carrier mates nowadays should have little problem re. loading such cargoes. Regards John Sabourn

[John Cassels]

Loading a modern bulk carrier is piece of ***. I beg to disagree. I loaded my last one ( 120000 T) more than 35 years ago
but the comments are still applicable.

Apart from having to be very careful re sheer forces and bending moments , the very speed that bulk cargoes are loaded at
makes them no less complicated than the much slower loading of a smaller conventional ship.
Make a mistake in the final loading runs at 6000 tph then one has a very big problem.

And if the worst does happen , shifting or discharging again is much easier on a conventional ship and well nigh impossible
on a bulk carrier .

[j.sabourn]

Hi John, I was comparing the loading advantages of a bulk carrier as against the convential cargo ship. I implied that with loading a bulk carrier with grain was a piece of p...s as against the work and fitting out for a grain cargo on a conventional cargo ship. Being on both types of vessel I know I would much prefer the easier of the jobs the bulk carrier. Best Regards John Sabourn

[Captain Kong]

I was in Dunkirk a few years ago, loading a cargo of 3000 tons of slag from the steel works there, one long hatch and hold, fortunately we had two 20 ton buckets and conveyors for discharging.
The French conveyor drivers were very unco-operative, His conveyer just poured in the slag starting forard,
I was shouting `Move aft` he shrugs his shoulders and carries on loading at the forard end. and it is all piled up there , She was well down by the head and the stern well clear of the water. The guy climbs out of his cab, I shouted a few expletives at him, all he did was shrug his shoulders and say` Ee Or, Ee or EE or`which I think in French means I dont give a damn, I said `you could speak English in 1940 on that beach over there you b45t4rd.` He cleared off.
I was left at 3am with my ship way down by the head.
I had to get all hands out to rig up the buckets and then drag the slag down aft until we had a good trim.
So without the cooperation of the shore people it can be rather difficult.
Cheers
Brian

[j.sabourn]

Brian some have in the past given Seven Isles (Sept Isles) as an example of fast loading I think was about 8000 tons an hour. However if you had your sequence of hatch loading corresponding with your final discharge of ballast it wasnt too bad. Obviously one didnt just dump in 8000 tons a hatch. Most mates had slightly different ideas, I used to start off at 2000 tons a hatch in alternate hatches to suit trim for stripping of ballast. Always kept 1000 tons for the final dump in the forward and after hatches shared between the 2 as required. However the loading sequence had to be adhered to as once they started loading there was no stopping them until the final 1000 tons. One used to hope and pray that the final ballast had been stripped. I think total loading time was about 4 hours and this was a lot of years ago. As regards grain loading this was as fast as they loaded for the port, made no difference what type of vessel this was in most ports. So cant see any bulk carrier loading faster than a convential cargo vessel. I know it can be a nightmare when there is little or no correspondence between ship and shore, and is situation everyone dreads. I loaded Grain in Halifax on a convential ship which was already fitted out from a previous cargo, however the next cargo involved sample corn and a lot of flax seed S.F.s approx only. I had a bit of a do with surveyor saying the ship was ready to load, and his reply was what happens if these S.Fs are incorrect. Anyhow we went ahead and loaded and he remained there throughout the loading. However I found out later he was the surveyor who had been present for the loading of the British Ambassador which was lost shortly before this, so he was taken no chances and cant blame him for that. I think my biggest problem on Bulk Carriers was getting all the ballast stripped. Regards John Sabourn.

[Capt Bill Davies]

Tony,

The loading of ‘large bulk carriers’ was not so much complicated but ‘stressfull’ if you will pardon the pun.
One has to wonder whether the Naval Architects who designed these ships had any operation experience at all. When considering Bending Moments (the ships propensity for emulating a banana) and the Shearing Forces ( the propensity for bulkhead structures to part company with adjacent members) one has to monitor the loading operation very carefully. This is compounded by how the vessel is loaded, homogenously (every hold) or alternate/block loading which is undesirable.
To explain this consider the standard cargo ship you sailed in, three hatches forward and two aft as an example. Now consider loading No.1 and 3 hold and leave No. 2 MT. Imagine the forces (shearing) acting on the bulkheads between 1 and 2 and holds 2 and 3. I think you can get the SF picture.
Take a look at Iron Ore ports and the loading rates found in some of the ports therein. 15k per hour is possible.
Further, there is a vast difference in static load and dynamic load from this loading rate which plays havoc with the structure .
Did Naval Architects take this dynamic load into consideration.

Cracking iwo hatch corners and others areas is common place in OBOs, O/O and conventional Ore Carriers. Gouging out and welding very common. Complicated in O/O wrt gas.

Human error played a large part to as did custom of the port in ‘clearing the belt’ which could result in overloading.

This is a BIG topic Tony and I am sure we will hear more from contributors.

Brgds

Bill