Assembling detailed information on submarines is a “bit at a time” job. At comments “August 25, 2015 at 6:31 PM” for http://gentleseas.blogspot.com.au/2015/08/ss-response-to-7-problems-with-japanese.html“S” provided the Soryu structural diagram above.
S accompanied the diagram (made open source at http://livedoor.blogimg.jp/wispywood2344/imgs/8/b/8b3c1df9.png) with the following notes:
The Soryu hull structure consists six sections. From right-hand side head to left-hand side tail the:
i) first section (head) has double and single hull structures [Pete Comment – complicated due to varying loads/considerations for bow streamlining, torpedo tubes, front escape tube and hatch to sail];
ii) second, third and fourth sections have a single hull structure;
iii) fifth and sixth sections have double hull structures. [Pete Comment – complicated due to rear escape tube and rudder-propeller hydrodynamics considerations]
The double hull consists of the outer non-pressure hull (non-magnetic alloy) and the inner pressure hull (magnetic NS-80). The inner pressure hull (NS-80) is not as strong as the single pressure hull (NS-110), because the outer hull (alloy) shows high strength.
The single pressure hull is made of low magnetic NS-110, in S’s opinion.
[For a future Australian submarine] To achieve overall low magnetism for this submarine (as it will not use NS-110) new low magnetic and high strength steel is needed for the single pressure hull, i.e. first partial area and second/third/fourth areas.
[Pete Comment – so the difference between “double-hulled submarines” and “single hulled submarines” may not be as distinct as is generally thought - rather its as complex as most other submarine matters. In the absence of NS-110 use various steels between HY-100 and NS-110/HY-156 may be appropriate.]
Pete