| It was an experimental design and as the article says, it was very expensive. Titanium was not just expensive, but it was hard to use. Welding had to be done in an inert gas chamber. Imagine building an inert gas chamber for a submarine. More info about it here https://foxtrotalpha.jalopnik.com/russias-alfa-class-was-the... I think that's a better overall article than the original link. New reactor design was experimental as well. Lead bismuth mixed had to be kept 120'C or higher. But it was much easier to increase it power momentarily, say if they wanted to chase someone. There is also a youtube video about it among others: https://www.youtube.com/watch?v=IJ34mE-aCdY (in Russian though) https://www.youtube.com/watch?v=lO6FZ_ztzKM In one of the videos they mentioned when they did sea trials, the speed got so high it stripped the paint off. It was also fun to show off their new toy to the Americans. |
Titanium welding is typically done by purging the air around the weld and/or pumping the inert gas into the parts being welded assuming they're tubes, etc.. A bunch of the gasses involved are heavier than air and that property can be used to come up with clever solutions.
Maybe the Russians built a giant chamber but that seems like a very non-russian solution considering their great awareness of KISS. More likely they found a way to seal an area around the weld and weld in sections that allowed them to pump inert gas into small areas near the welding equipment.