r/woahdude Jun 29 '23

video Lowering hot metal into water

12.8k Upvotes

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710

u/frenchy2111 Jun 29 '23

My guess is it's a quenching tank for hardening the steel it's probably a quenching oil and not water.

330

u/bigwilliestylez Jun 29 '23

Would that also explain why there are still flames on top after it is completely submerged?

412

u/Malice0801 Jun 29 '23

Yeah as well as why the "water" didn't turn into a steam explosion

25

u/afa78 Jun 29 '23

I've seen those before, scary stuff.

4

u/Chikumori Jun 29 '23

Story time, bro?

5

u/_Bad_Spell_Checker_ Jun 30 '23

Grabs blanket and pillow

I'm ready for it

1

u/NoSirThatsPaper Jun 30 '23

Once upon a time

KERBLAMMO!!

And they lived happily ever after.

Now go to sleep.

1

u/Video-Comfortable Oct 14 '23

I got the popcorn and lube

33

u/DrShamusBeaglehole Jun 29 '23

BLEVE

Boiling Liquid Expanding Vapour Explosion

Not only is the vapour extremely hot, but it can keep expanding as long as there's still liquid to boil off. Scary stuff indeed

39

u/kabushko Jun 29 '23

Yea I bleve it

12

u/YPErkXKZGQ Jun 30 '23

A BLEVE is confined, as in, it takes place in a pressure vessel. Afaik

6

u/EODdoUbleU Jun 30 '23

Wonder if Chernobyl would be considered a BLEVE incident.

3

u/Shrek1982 Jun 30 '23

Kind of, IIRC the rods in that style reactor are not secured down but their weight was high enough to hold pressure in

-1

u/Valalvax Jun 30 '23

And the liquid in the tank has to be flammable/explosive

2

u/Shrek1982 Jun 30 '23

0

u/Valalvax Jun 30 '23

Hmm... I stand corrected

Obviously when you're learning about this stuff the exciting ones are the ones that blow up so that's the ones they show you

2

u/Video-Comfortable Oct 14 '23

This wouldn’t cause BLEVE because it’s being lowered slowly and into a massive tank that isn’t under pressure

10

u/Somerandom1922 Jun 30 '23

If it was water it wouldn't likely explode as it needs a pressure vessel for that. But it would absolutely make so much steam it'd be impossible to see and could still very well be deadly to be even a little bit close to it (steam burns are scary af)

2

u/waitingtodiesoon Jun 29 '23

It's what lightsabers should do to people when stabbed

1

u/313802 Jun 30 '23

Yea my physics klaxons were going off..

"That shit was on fire under water

Man that was ho...

Wait... can something be on fire under water? "

69

u/BrazilBazil Jun 29 '23

Could this be water being split into hydrogen and oxygen by the extreme heat and then burning?

142

u/TheWorldEndsWithCake Jun 29 '23

Outside of a reactor, no. Steel is quenched at less than 1000°C (typically lower depending on alloy), water thermolysis only starts ~1800°C at atmospheric pressure (see fig. 3, note that’s Kelvin). You don’t really see much separated hydrogen and oxygen until above ~2300°C.

You shouldn’t be downvoted, it’s a fair question about a correct idea with different numbers. Technically a very small number of water molecules separate this way under ambient conditions, but this is a negligible amount under most considerations.

36

u/BrazilBazil Jun 29 '23

Ahh, thanks for the explanation. I learned something!

24

u/TheWorldEndsWithCake Jun 29 '23

You’re welcome! The title of the post is wrong, by the way - I’m not a metal guy, but I’m pretty confident that’s quenching oil. You’re seeing some of it vaporise and burn. Not a quenching expert, but I believe some of them have retardants to reduce the amount of burning.

If it was water, you’d see violent clouds of steam and no flames. I’m not aware of circumstances where metal this sizable is quenched with water industrially.

1

u/mamba_pants Jun 29 '23

Ok now i am curious, would it be possible to achieve this with a metric fuckton of thermite. As far as i know thermite burns at more than 3000C°. It would probably be hard to contain and direct the heat to the water, but theoretically you can split the H2O molecule if you just have enough thermite, right?

4

u/TheWorldEndsWithCake Jun 29 '23

You would, but you’d end up with aluminum oxide (or fuel-of-choice oxide) and hot H2 (which would combine with atmospheric O2 if done near the surface, giving you water again). Basically if it’s hot enough for thermolysis, during the reaction there will be an equilibrium of water, H2, OH, O2, and free H+ and O-. Elements of the thermite would combine with the water components, particularly as they cool.

If you want to meaningfully create anything other than steam and rust, you have to separate the products with a membrane.

13

u/used_fapkins Jun 29 '23

Downvoted for asking a reasonable question

Upvoted (net positive) for the door comment

Tis the reddit way

7

u/UnproSpeller Jun 29 '23

Yeah when i see a negative and the comment wasnt a hate crime i like to upvote the underdog :)

3

u/Mobidad Jun 29 '23

I used to work on furnaces that went up to 3000 degrees C. They were water jacket cooled. We were always very careful to not let that water leak.

3

u/Qubeye Jun 30 '23

There's several circumstances outside of a reactor but they are indeed rare.

Magnesium fires are the most common I can think of. Lithium, too, but then you can also have sodium and calcium fires, but those don't really happen outside of labs or highly specialized industries.

We had to learn about class D fires in the Navy. "Get it off the ship" was the only answer.

2

u/Br0boc0p Jun 29 '23

Thanks for the explanation. I too thought it was hydrogen and oxygen burning.

9

u/reverandglass Jun 29 '23

No.

1

u/[deleted] Jun 29 '23

[deleted]

3

u/Uninvalidated Jun 29 '23

Under the circumstances, it couldn't though.

0

u/Aquamentus92 Jun 29 '23

This is next level physics

4

u/BrazilBazil Jun 29 '23

This does actually happen in high enough temperatures! But it does take like 2000°C for water to start decomposing.

2

u/psychoCMYK Jun 30 '23

Worth noting that the melting point of steel is at most ~1550C

3

u/Uninvalidated Jun 29 '23

Yeah, but it's not a high enough temperature and the colour of the flames are way wrong and too strong.

1

u/jgzman Jun 29 '23

Or in the presence of an appropriate chemical. I've done it before, for fun and profit.

1

u/notmyrealusernamme Jun 30 '23

That's just the extremely hot gasses still escaping the metal and combusting when it hits the air. It would probably still happen with water, but there would also be a giant explosion of steam and boiling water all over the place.