Comment by rdtsc | Hacker News Reader

Comment by rdtsc | Hacker News Reader

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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.

They don't have to weld in an inert gas chamber.

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.

Ah ok. They were showing people putting on what looked like moon suits and going into a chamber. I imagine that's for smaller scale welds. But I imagine pumping argon under pressure to displace oxygen in some areas would work as well. Then ventilate properly as it would settle and well ... suffocate people.

It gave the Russians a lead in Titanium manufacturing that still exists today.

Is that so? I recall the reading a piece on the SR-71 and it mentioned that the titanium was, ironically, sourced from the Soviet Union who supposedly were behind in titanium tech. Further, I remember a following tidbit about one of their jets still being made of steel because of their supposed lagging metallurgical skills. Have they since leapfrogged the US?

If you read the linked articles here it was exactly that attitude that allowed the US to tell itself that it was impossible that the Russians had the capability to make a Titanium sub for about a decade.

https://news.ycombinator.com/item?id=17015111

IIRC the hull of much larger Russian nuclear subs (the ones that are always near the US East Coast) is made of titanium too.

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