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The Race to Seal Helium HDDs (2021)

blog.westerndigital.com

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Re: The Race to Seal Helium HDDs (2021)

#31

Post by ejdhshsuwisjsh »

ahartmetz wrote: post #27
Wowfunhappy wrote: post #25

...I didn't really we had the technology to seal helium at all. Stupid question, but could you potentially create a helium balloon that never runs out of helium (because it's sealed and doesn't leak)?

If it's made of metal foil, probably. Much more diffusion-resistant than rubber. The problem with rubber balloons isn't that they have macro- or mesoscopic holes. They lose gas by diffusion all over.

The article talks about how hard it is to contain helium.

Why would you assume that a basic metal foil would keep helium indefinitely?

Re: The Race to Seal Helium HDDs (2021)

#32

Post by Someone »

robocat wrote: post #20
exe34 wrote: post #5

Earlier quoted context omitted.

vacuums tend to collapse on themselves, I think it might be more costly in structural elements to prevent that?

It is better to think of a vacuum within air to be similar to a bubble underwater. Air is like water in other ways too. We slightly "float" in air by the weight of air we displace. e.g. 80kg person is approximately 80 litres (density of a body is 1.010 kg/litre). Weight of displaced air is approx 0.1 gram (1.2929 gram/litre). So the floating effect of air reduces your weight (not mass) by about 0.1%.

> It is better to think of a vacuum within air to be similar to a bubble underwater.

I don’t think it is vey similar. That bubble pushes against the water to maintain itself; it manages to do that only because its “push” increases the higher its pressure and it is more compressible than water.

The vacuum, on the other hand, is compressible (if you want to call that so), but its “push” remains zero if you do, so it needs help to push against the air to maintain itself.

That’s why the post your replied to said “vacuums tend to collapse on themselves, I think it might be more costly in structural elements to prevent that?”

Re: The Race to Seal Helium HDDs (2021)

#33

Post by ahartmetz »

ejdhshsuwisjsh wrote: post #31
ahartmetz wrote: post #27

Earlier quoted context omitted.

If it's made of metal foil, probably. Much more diffusion-resistant than rubber. The problem with rubber balloons isn't that they have macro- or mesoscopic holes. They lose gas by diffusion all over.

The article talks about how hard it is to contain helium. Why would you assume that a basic metal foil would keep helium indefinitely?

It's right there in the article: it mentions welding of aluminum foil seals - for helium.

I have also worked with high vacuum in lab exercises. There's a leak finder apparatus using helium because helium creeps through the smallest leaks - but they have to be leaks! Hydrogen just diffuses through anyway, though not quickly through thick metal (I have that from Wikipedia).

Re: The Race to Seal Helium HDDs (2021)

#34

Post by aaron695 »

rwmj wrote: post #8
wigster wrote: post #3

if helium is better, why not use a vacuum?

Hydrogen would also be .. interesting ...

> Hydrogen would also be .. interesting ...

Why?

It's used in power station generators. Why would a hard disk be interesting?

https://en.wikipedia.org/wiki/Hydrogen-cooled_turbo_generato...

Re: The Race to Seal Helium HDDs (2021)

#35

Post by Towaway69 »

> Western Digital ships about a million helium-sealed drives every month.

I'm surprised that there was such demand for spinning disks, I would have thought SDDs would have replaced them all.

I say ‚was‘ as the article is from 2021.

Re: The Race to Seal Helium HDDs (2021)

#36

Post by ricardobeat »

Towaway69 wrote: post #35

> Western Digital ships about a million helium-sealed drives every month. I'm surprised that there was such demand for spinning disks, I would have thought SDDs would have replaced them all. I say ‚was‘ as the article is from 2021.

SSDs are still too expensive for high volume storage.

Enterprise purchases will be much lower, but as a consumer you can buy a 12TB helium-sealed HDD for $100-$200, while solid state alternatives don’t even reach that capacity in a single unit and cost 5-10x more.

Re: The Race to Seal Helium HDDs (2021)

#37

Post by amelius »

vertnerd wrote: post #19

"Helium is notoriously difficult to contain. Its atoms are some of the tiniest in the universe." It's a good article, and I learned a lot, but every so often it reads like something an 8th grader would write the night before their paper is due.

Sometimes facts are simple.

Re: The Race to Seal Helium HDDs (2021)

#38

Post by amelius »

ahartmetz wrote: post #30
akira2501 wrote: post #11

Earlier quoted context omitted.

A gas provides a "bearing" for the heads to ride on as the disk spins below it.

Maybe magnetism could work. HDD platters take very strong fields to change magnetization these days, so erasing the data with the positioning magnet(s) seems avoidable.

So write too many zeros to your drive, the disk becomes demagnetized, and the head will crash?

Re: The Race to Seal Helium HDDs (2021)

#39

Post by ItsBob »

exe34 wrote: post #5
wigster wrote: post #3

if helium is better, why not use a vacuum?

vacuums tend to collapse on themselves, I think it might be more costly in structural elements to prevent that?

What about a partial vacuum?

Perhaps there is a hapy medium between air resistance and cushioning? Reducing the air by an amount might help.

Although, I'd be surprised if they hadn't thought of this already :)

Re: The Race to Seal Helium HDDs (2021)

#40

Post by dtx1 »

aaron695 wrote: post #34
rwmj wrote: post #8

Earlier quoted context omitted.

Hydrogen would also be .. interesting ...

> Hydrogen would also be .. interesting ... Why? It's used in power station generators. Why would a hard disk be interesting? https://en.wikipedia.org/wiki/Hydrogen-cooled_turbo_generato...

Cause exploding hard drives are metal AF
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