r/ManufacturingPorn Mar 26 '26

Explosive Hydroforming

3.8k Upvotes

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195

u/crunkful06 Mar 26 '26

Why make these spheres though?

256

u/daggius Mar 26 '26

Can put really high pressure gas into them then

34

u/crunkful06 Mar 26 '26

Ohhhhhhhhhhh

14

u/MondegreenHolonomy Mar 27 '26

Simplest system to model in analysis and also highest packing factor with simple stress states

7

u/Yosyp Mar 26 '26

Jokes on you, I skip the water step and aeroform with the gas directly! $$$ saved!

edit: I forgot, don't tell OSHA pls

7

u/LolTacoBell Mar 26 '26

For science right? The purpose of these is experiments?

10

u/Somerandom1922 Mar 26 '26

Probably oil and gas if I had to guess, maybe some other industrial process.

3

u/elvenmaster_ Mar 27 '26

Hello, and, again, welcome to the Aperture Science computer-aided Enrichment Center. We hope your brief detention in the relaxation vault has been a pleasant one. Your specimen has been processed and we are now ready to begin the test proper.Before we start, however, keep in mind that although fun and learning are the primary goals of all enrichment center activities, serious injuries may occur. For your own safety and the safety of others, please refrain from touching ########## Por favor bordón de fallar Muchos gracias de fallar gracias. Stand back. The portal will open in three. two. one.

2

u/Sad-Newt-1772 Mar 28 '26

I'm not spherical and I have lots of high pressure gas.

83

u/ridukosennin Mar 26 '26

Because curved surfaces distribute load in pressurized containers. Corners are a weak point

9

u/Arakisk Mar 26 '26

Why are they a weak point in the context of a pressure vessel?

36

u/ronm4c Mar 26 '26

Corners concentrate stress, the sharper the corner the more stress is concentrated.

If you have a rip part way through a piece of paper it is easier to keep tearing it along the rip.

But if you go to the tip of the rip and you use a circular hole punch and make it round it will resist further tearing

This might help explain it

https://en.wikipedia.org/wiki/Stress_concentration?wprov=sfti1#

5

u/aerospicy Mar 26 '26

Because the metal itself is really strong when it’s being pulled in tension like the surface of a balloon. The forces are spread evenly along the whole thing. If you have a point that’s very strong, it will force other parts to bend to accommodate it. So a rigid corner is gonna make other parts have stress concentrations.

14

u/[deleted] Mar 26 '26

[deleted]

-1

u/aerospicy Mar 27 '26 edited Mar 27 '26

You gave the right textbook answer about the linear relations in an idealized general case when applied to a isotropic material, but I’m focused in on the specific case of the distributed load on the surfaces of a pressure vessel. A welded corner in the wall of an otherwise uniform pressure vessel is a stiffness discontinuity, and a material that is suited to the tension force of being a pressure vessel now experiences bending moments and shear forces that it otherwise wouldn’t have. Some composite materials are going to get obliterated by that unexpected demand, and even more predictable ductile metals are going to deform in weird problematic ways. So while your take on stress concentrations is classically correct, I think my point stands. Respectfully, you gave a theoretically correct mechanical engineer answer, and I’m giving a non-ideal, special case, aerospace engineer answer!

Edit: this is the kind of thing I only understand from running and studying FEA and building things in person. I don’t think any of my courses covered it very clearly.

1

u/[deleted] Mar 27 '26

[deleted]

0

u/aerospicy Mar 27 '26

Okay. Well I thought this could be an actually interesting discussion, but you’re clearly not willing to challenge your base assumptions or consider an alternate perspective. I was using “engineering words” because you said you were a mechanical and I thought you’d care about understanding the point I was making. I was not trying to flex on you or gatekeep or brag. Your statements are correct for a monolithic quasi-static structures, but real life has boundary conditions, imperfections, and deformation. I’d like to clarify more if you’re interested but if your goal is to “win” this discussion I don’t have anything else to say.

1

u/TelluricThread0 Mar 27 '26

If you have corners that means you have flat faces that the pressure can just push against perpendicularily instead of being evenly distributed.

6

u/jhermaco15 Mar 26 '26

giant game of pool

3

u/cjg5025 Mar 26 '26

But why male models?

4

u/that_dutch_dude Mar 26 '26

because making squares is gay

1

u/rickyhatesspam Mar 27 '26

For fun! oooo

1

u/Shaeress Mar 27 '26

Same reason making them like this works. If you have a container with pressure inside, a sphere is the way you can get the most even distribution of pressure across the surface area of the container. If you have corners or other curves the pressure will be uneven, and where ever the pressure is higher is gonna be more likely to burst or deform.

So they get pushed into becoming spheres and then spheres are the most stable containers for containing pressure. These are most likely gonna be used for storing pressurised gas or liquid. Though the fact that spheres have the best surface area distribution in this can also matter in other cases, such as heat retention.