military Shipbuilding in general and the question: carrier or not a carrier?

lcloo said:

It is simply a different approach of building method. Compare with traditional building method, modular building needs far greater precision in all dimensions, errors of few millimetre may be allowed but errors in centimetres can ruin in big time when two large super modules are mated together as every edges and corners of the two modules must match each other millimetre by millimetre before proper welding took place.

Building a ship from keel upwards is far more easy but time consuming, and this method has greater tolerance for errors which can be rectified by mending or cutting away a few inches of unwanted steel plates. The hulls are normally supported by walls aka bulkhead instead of beam, as the ship becomes larger in progress.

Temporary use of beams and pillars are there to prevent deformation take place, this is critical especially you do not want a deformation of even just a few millimetres. This does not mean Chinese ships do not have bulkheads to support the hull as in western ships, they know better than anyone else since ship bulkhead was a Chinese invention hundreds of years ago. Or you can say it is simply an over-engineering in methods of building a ship.

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Anlsvrthng said:

Compare the two picture.

Lot of support bar on the structure in the Chinese yard, 0 on the Ford building at the same phase.

The QE hasn't got any as well.

Now, this needed because without the top deck the structure is not rigid, and can deformate .

Now, it is a warship, so has to withstand an explosion under the kneel (within limits) .

There should be many walls in the structure as well.

That structure looks like the hull of a bulk carrier , or oil tanker, not a military ship.

Of course it can be same new structure, half finished and so on, but it would need only sheet metal to be rigid, without the support bars.
View attachment 55321

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Tam said:

QE and Ford construction process also don't cover the ships while they are under construction. Neither did 002, nor did the 075. 003 did however, much like super tankers and huge container ships. Is that a sign of lower grade commercial construction over military construction?

No. It is the other way around. These methods were developed around the time when the Japanese began building super tankers and container ships that were by far the largest in the world, the size and length of these ships created unforeseen and unprecedented construction problems. Once these were developed allowing the modern age of mega sized commercial ships to happen, Japan was on its way to becoming the largest shipbuilder in the world, while the US shipbuilding industry went to rapid decline.

The reason why the modules are covered, is that under the weather, under the sunlight and under different temperature conditions, the modules will thermally expand and contract. This meant that the modules will not fit properly together after different rates of thermal contraction and expansion. Try to weld the modules, and they will not weld and seam properly. This can result in leaks. Covering the modules like they did building the 003, means you can put thermal controls on each module to restrict and regulate their rates of thermal contraction and expansion.

I am not sure if those are support bars, they look to me bars placed on top and around the modules that are also used to keep the modules from deforming due to thermal expansion and contraction.

Comparing is useless because you also need to see the size and tonnage of the ship being constructed. You don't need to do this on smaller ships as you do with much larger and longer ships. Of if the ship has much more seams between the modules that you need to weld.

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Anlsvrthng said:

IT is a bit stretch to call it as a modern construction method.

These are the same problems and solutions that the builder face during the construction of a wooden ship. ( wood will deformate due to sunshine/ moisture )
I'm sure if you check a 2000 years old Chinese yard you see similar support structures for the half finished wooden ships.

It is slow, because restrict the number of welders capable to work on the ship, but it is less merciless with the manufacturing mistakes / design issues.

And bigger ships on the Shanghai yard made with smaller/ next to nothing support structures .

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Tam said:

No its not. Wooden ships are simply not built in the way you describe. It is simply impossible since wooden ships are built end to end, not in modular sections.

Find out that a module that was exposed to sunshine while others are exposed to cold, forces modules to not fit together during welding. This wasn't much of a problem since seams can be heated till they can be joined. Until the super tanker era that is.

What makes you think that bigger ships in "Shanghai yard" are built with smaller or next to nothing support structures. Many shipyards not just in Shanghai but around China use sheds and built ships within sheds. Jiangnan included. So you cannot see what goes inside.

Or would you be confusing billet or overhead cranes as these support structures? From the air, they would look like that.

View attachment 55348

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Anlsvrthng said:

The internal of this ship is still strange.

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Anlsvrthng said:

It

Those are support bars.

Crane needs rails, and that can be quite expensive (and pointless) to build into a half finished ship.

Check the picture bellow.

As it looks like they working on many segments at the same time, and from time to time they test if the fit.

It is actually the very same method that the carpenters used to make a ship since the dawn of time. View attachment 55355
The horizontal bars are the supports, later during the manufacturing they remove them one by one.



View attachment 55354


The internal of this ship is still strange.
Looks like a very long bay , and the other carriers has lot of internal bulkheads and so on.
It can be just the unfinished structure.

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Tam said:

Support bars are put on the middle of the hull, where the hull need to be strongest and you put the bars between the bulkheads. You don't put it on the top of the hull, and not on top of the bulkheads. The bars are positioned so they are not supporting anything. They look like billet or overhead girder shaped cranes to me. Furthermore, it does look like there is a rail on each side where the girders are attached to. There are hand rails along the girders, so that also looks like a crane. They are also colored like cranes.

Being expensive is not a reason why it should not be there if they are not sparing any cost. The ship is mostly keel and bulkhead at this point, that is not half finished by any means. It would make sense to put cranes inside the hull to move heavy parts around. I cannot see any means how heavy metal objects can be moved and stationed inside the hull.

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