Crush Depth for an Empty AL80?

[NAM001]

an egg can do better than that. I know its not the same...

According to the math on this site (which is based off research by Wood's Hole OI), an AL80 made out of 6061 aluminum, with a wall thickness of .521" and an OD of 7.25" should yield at about 3500 meters and buckle at about 5750 meters.This, of course, assuming that by "sealing", you mean that the neck is plugged using a method that's at least as strong as the rest of the tank. A scuba valve should fail long before the cylinder itself does at extreme depths.Call up Jamie and Adam, and let's start a new thread... "I'd like to see a scuba tank explode... UNDERWATER." =)

 

[lucca brassi]

From what I was reading, crush/yielding depth is a function of wall thickness/outer diameter and material strength. The higher the ratio, the deeper you can go.

crushing it is also very heavy function of shape and structural design . ( that's' why have bathysphere .... sphere shape and it is difference if you have uniform wall thickness or you have reinforcements at the bottom in the form of thicker walls.

In practice , analysis can be made '' finite element method '' but you need good model (how it is model made Simplify FEA Simulation Models Using Planar Symmetry - Desktop Engineering ) with precise measurements of real scuba tank

some analysis is there https://www.rose-hulman.edu/~olson1/ME422 Web Site/Sample Reports/Scuba_Cylinder.pdf but that is for corrosion purposes

but the best way is DM ( destructive method ) test in lab ....... it helps vacuum inside ;-))

http://www.thejot.net/site/?page_id=837&show_article_preview=84&jot_download_article=84

 

[emoreira]

A nice drawing about depth facts.

 

[NAM001]

i dont think there is enough depth to crush one. if it does crush it will be form the flat end of the tank. look at pics of the uss scorpion on the bottom. still round but was telescoped to gether. I want to say that there are some scuba tanks shown on the bottom there. Pressureized i an sure with probably 2000+ psi in them, but never the less that is is equivilant to 4-5k feet of depth.

---------- Post added September 15th, 2015 at 01:19 PM ----------

being stationed on one of those ww2 boats i can say the depth you cite may be a bit off. don't confuse operating with test with crush depths. On old tv when there was a mid night sign off for the day, the national anthem would play and show a ww2 boat launching out of the water and dropping back in. I believe that boat shown was out of key west sub base and when if went back into the water at like a 70 degree up angle. it went back to 1000 ft before it started back up again. most of the boats of that era had their operating depth limits set to around 400 ft later in life.

holy cow! don't you mean feet?

WWII subs had crush depths of around 300 meters, and modern subs something like 750 meters

---------- Post added September 15th, 2015 at 01:31 PM ----------

watch this video. I knew i could find it if i looked long enough. look at 3:30

https://www.youtube.com/watch?v=FSNlBqHTJcg