CV-18 Fujian/003 CATOBAR carrier thread

Orthan said:

why do you say that that is the shipyard where the ship will be build ? it surely seems small for a big aircraft carrier project. Why not the bigger dry dock in its left side?

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I'm quoting it from the fellows on the Chinese forums. They are saying it will be built there, and I am happy to defer to their words in this case.


As for size -- it is definitely big enough to build a supercarrier, it is similar in the relevant dimensions to DL's drydock and Newport's dock 12, so I can't really foresee problems with building an 80,000 ton carrier or even 100,000+ ton carriers later on.

The drydock on the left is indeed bigger, but it's so big that it is unnecessary.

Bltizo said:

here:

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Is the lower part of the photo a recent pic? I do not know the reltive dimensions, but the form of that ship looks like a carrier. Is that the just launched carrier, or is that the 3rd carrier?

Jeff Head said:

Is the lower part of the photo a recent pic? I do not know the reltive dimensions, but the form of that ship looks like a carrier. Is that the just launched carrier, or is that the 3rd carrier?

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I made that photo back in 2016 I think. I used GE with screenshots taken at the same visual altitude of all three drydocks, to compare the dimensions of the drydocks themselves.

The bottom part of the photo shows Dalian's drydock with 002 (i.e.: CV-17) when it was under construction back in 2016 or late 2015, before it was launched last year and of course long before its first sea trial this year.

Orthan said:

... it surely seems small for a big aircraft carrier project. Why not the bigger dry dock in its left side?

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Some more thoughts:

• civilian ships are larger than aircraft carriers, so the larger drydock is reserved for civilian ships.
• the gantry crane over the smaler drydock can lift 1600 tons, the other two gantry cranes over the larger drydock can lift only 900 tons each.
• there is space near the smaler drydock for new buildings for a new kind of ship type.

Long post ahead, but I recommend everyone to pay proper attention. This is important information.

I've been doing some reading up on the modern modular construction of ships. It's fascinating and shows how much we have yet to learn.

First, the gantry crane maximum lift capacity stuff that we're used to - get that out of your head.

The days when ships had to be pieced together with ~1000-ton modules are in the past. Now, we're talking about multi-thousand ton modules, pre-fabricated in different locations before being floated into drydock for assembly. This is what fzgfzy meant when he said a few weeks ago that the 003 was being constructed "all around Shanghai" (not a literal translation, but is direct).

In my last post, I mentioned that the carrier would be constructed as:

First, basic parts and small modules will be laid down and assembled, followed by medium-sized modules, and finally, the massive ones...

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This is not untrue, but it is poorly worded. What I meant was that in order to construct the ship, small parts have to be assembled into medium modules, and the medium modules assembled into large modules, and finally the large modules are put together to complete the hull.

That being said, Asif Iqbal is not wrong.

asif iqbal said:

I doubt that

Carrier construction requires large blocks there is no small ones, for the lower part block construction you will have the biggest blocks

if the 80,000 ton mark is the final weight of 003 some of these lower blocks will weight over 10,000 tons that's like lifting a entire Type 055

these days with module construction they will first lay that into the dry dock and I cant image it will be small and call it keel laying and to me that looks like a front end lower block

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You might be thinking how it's possible to build a ship with multi-thousand-ton modules at different places and move them into place.

Intrepid said:

These are unrealistic numbers. As an example: CVN 78 Ford was composed of 162 so-called "superlifts", the heaviest weighed 1050 tons (which is the maximum load capacity of the huge gantry crane).

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The answer is, not with gantry cranes, as many of us (myself included) still believed ships had to be built with.

A very good example is Britain's new carrier, HMS Queen Elizabeth, was constructed using modular build. The largest of these giant 'core' modules weighed a staggering 11,300 tons, while the other 5 core modules weighed between 4,000 and 8,000 tons. The work was divided between five separate contractors.


They were fabricated and assembled at various facilities, transported to the place of final assembly by barge, and then floated into drydock piece by piece. Smaller, 1,000-ton and sub-1,000-ton components like the island will, of course, still have to be craned into place.

See 6:30 in the video.


So, in the JN drydock, what exactly is it that we're looking at?

If we're going with the rumor that 003 will be constructed in this modular fashion, then we're seeing the start of the assembly of one of the giant modules. Moreover, this is only one shipyard that we've heard about so far - for all we know, multiple yards could already be working on their own large modules, to be assembled in JN in the future. The one that's about to take shape in JN may not even be the first one.

Exciting times ahead, friends. I'll keep everyone updated as best as I can.

Higgle said:

Long post ahead, but I recommend everyone to pay proper attention. This is important information.

I've been doing some reading up on the modern modular construction of ships. It's fascinating and shows how much we have yet to learn.

First, the gantry crane maximum lift capacity stuff that we're used to - get that out of your head.

The days when ships had to be pieced together with ~1000-ton modules are in the past. Now, we're talking about multi-thousand ton modules, pre-fabricated in different locations before being floated into drydock for assembly. This is what fzgfzy meant when he said a few weeks ago that the 003 was being constructed "all around Shanghai" (not a literal translation, but is direct).

In my last post, I mentioned that the carrier would be constructed as:



This is not untrue, but it is poorly worded. What I meant was that in order to construct the ship, small parts have to be assembled into medium modules, and the medium modules assembled into large modules, and finally the large modules are put together to complete the hull.

That being said, Asif Iqbal is not wrong.



You might be thinking how it's possible to build a ship with multi-thousand-ton modules at different places and move them into place.



The answer is, not with gantry cranes, as many of us (myself included) still believed ships had to be built with.

A very good example is Britain's new carrier, HMS Queen Elizabeth, was constructed using modular build. The largest of these giant 'core' modules weighed a staggering 11,300 tons, while the other 5 core modules weighed between 4,000 and 8,000 tons. The work was divided between five separate contractors.

They were fabricated and assembled at various facilities, transported to the place of final assembly by barge, and then floated into drydock piece by piece. Smaller, 1,000-ton and sub-1,000-ton components like the island will, of course, still have to be craned into place.

See 6:30 in the video.

So, in the JN drydock, what exactly is it that we're looking at?

If we're going with the rumor that 003 will be constructed in this modular fashion, then we're seeing the start of the assembly of one of the giant modules. Moreover, this is only one shipyard that we've heard about so far - for all we know, multiple yards could already be working on their own large modules, to be assembled in JN in the future. The one that's about to take shape in JN may not even be the first one.

Exciting times ahead, friends. I'll keep everyone updated as best as I can.

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appreciate your efforts in posting info from the boards.


I've been wondering for a while if JN may be building modules in larger CVF style blocks as well, in fact even prior to when 002 began construction I wondered if China might eventually take such an approach with its carrier construction.

That said, it would be a bit of a change for JN to receive modules from multiple different sites and yards like in the case of CVF.
In the case of CVF, there were some industrial limitations and politico-economic reasons for having its modules be pre-built at multiple different yards around the UK prior to final fabrication, and I'm not sure if those same limitations and reasons exist for China or JN.


That said, if fzgfzy has indeed strongly indicated that modules for 003 are being built "all around shanghai" and the use of the word "shanghai" is referring to the actual administrative city/area rather than as a shorthand for JNCX, then a CVF style workflow may indeed be likely.

To add on to my last post, we know that Chinese shipyards are fully capable of this method of construction.

In 2009, China Waigaoqiao Shipbuilding successfully completed a 177,000 DWT bulk carrier, hull number H1133. The 90,000-ton ship was constructed out of 6,000-ton modules. This is just one example - many other ships have been built with this modular method .As early as 1991, Shanghai HDZH was already putting modular construction to the test in the form of 47,500-ton bulk carriers.

Due to the intricacies the giant modules, this method of shipbuilding requires a very high level of precision in module alignment, down to the millimeter.

Fortunately, Chinese shipyards already have at least 25 years of experience with modular construction.

Links:

Bltizo said:

appreciate your efforts in posting info from the boards.

...

That said, if fzgfzy has indeed strongly indicated that modules for 003 are being built "all around shanghai" and the use of the word "shanghai" is referring to the actual administrative city/area rather than as a shorthand for JNCX, then a CVF style workflow may indeed be likely.

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Being able to help out is a pleasure.

I'll see if I can find the post where he mentioned that. It was from a while ago so it might take a bit of digging.

continuing with the possibility of a CVF workflow for 003.... that takes me back to the famous carrier "demo module" from back in 2013.

At the time, obviously its dimensions were not consistent with any functional carrier despite having the cross section not dissimilar to a carrier. I also remember thinking that the module was sort of similar to images of CVF modules, in the sense that it was obviously a single very large block, and that it was a big "cross section" whose anterior and posterior were both "sealed" off as well, again, similar to CVF modules when they were transported to Rosyth, and different to how modules say for 002 were "open ended" at the front and back when they were being assembled at Dalian

So I have to wonder if perhaps the 2013 carrier demo module may have had a role in trialling the potential of a CVF style workflow for 003.... even for a while, the demo module was placed right in front of drydock #4 where 003 is expected to be assembled!

Bltizo said:

That said, if fzgfzy has indeed strongly indicated that modules for 003 are being built "all around shanghai" and the use of the word "shanghai" is referring to the actual administrative city/area rather than as a shorthand for JNCX, then a CVF style workflow may indeed be likely.

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Found it, from 1 June of this year.

本猫的观点也表述过，是上海造航母，二号线的泸东及其他相关厂可能承担约40％分段建设，目前本猫并没调整观点，只是配合厂的承建比例是大大下降，等最终合并结果出来再说。从2015开始到现在的几年，江南确实有非常大变化，四号坞所有权确定，并开始相应的改造。建了相当规模的新厂区（图1），加大产能的提升。目前二号线及相关周边的所属权，也可能有调整变化，我相信这一切都是给江南更好的有能力建造航母铺路。

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Roughly translated, fzgfzy's belief is that the carrier will be constructed in Shanghai. Secondary yards (i.e. not JNCX), including HZHD and others, might construct ~40% of the required modules for the carrier. However, he believes that it is too early for a firm interpretation, for the following reason. From 2015 to now, JNCX has undergone many changes. In particular, the expansion of the yard with dock #4 greatly improved production capabilities, allowing JNCX to take more construction load off other shipyards than originally planned (for 003). The aforementioned 'secondary' yards are also undergoing improvements, which fzgfzy thinks will give JNCX an easier time in carrier construction.