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View Full Version : Be Careful with 02


bgbill
05-10-2007, 07:54 PM
http://www.youtube.com/watch?v=9lw_fhNAIQc

f94gator
05-10-2007, 08:16 PM
Holy crap.

deepdestroyer
05-10-2007, 10:01 PM
Wow, that sucks!

Petra
05-11-2007, 06:55 AM
Dayum! But I don't get WHY it exploded? What did he do wrong?

huntinfish
05-11-2007, 06:55 AM
I can repair that, my dad's a t.v. repairman and he's got an awsome set of tools. ;)

AlexF
05-11-2007, 07:13 AM
When I first read the post I thought it had been due to oil (oxygen and oil are a big no-no) but then I saw the video.

Wow. It's amazing the force compressed gases have.

dagodiver
05-11-2007, 07:17 AM
Dayum! But I don't get WHY it exploded? What did he do wrong?


Used a tool on a tank that had pressure in it was his first mistake.
The O2 had nothing to do with it. Pressure is pressure, and when you work with it be careful. Scuba tanks are not even in the high pressure range of things and this stuff will still bite you if you are not careful.



Dago.

dagodiver
05-11-2007, 07:18 AM
Tip Of The Day
Do not drive with two large, unsecured O2 cylinders rolling around in your truck bed after drinking multiple Asahi beers, and Rage Against The Machine cranked on your Sirius satellite radio. This has been your tip of the day. Thank you....

Well than you wont be riding around with me in my work truck.! :eek:


Dago.

Petra
05-11-2007, 07:19 AM
I can repair that, my dad's a t.v. repairman and he's got an awsome set of tools. ;)

"You can't fix that, Spicoli..."

"Dude, I can fix it."

"My brother's gonna shit. He's gonna kill us. He's gonna shit."

"Make up your mind, dude. Is he gonna shit or is he gonna kill us?"

"First he's gonna shit. Then he's gonna kill us."

:thumps:

dagodiver
05-11-2007, 07:33 AM
When I first read the post I thought it had been due to oil (oxygen and oil are a big no-no) but then I saw the video.

Wow. It's amazing the force compressed gases have.



So I should not strap my T-bottles to the drum of 9250 anymore.? :D

It should say; be careful with compressed gas.!
Problem is that most people get there knowledge of O2 from dive class. :rolleyes:


Dago.

AlexF
05-14-2007, 09:11 AM
Ok, kept on thinking why the tank exploded, and things were not very clear to me so I went out to the family business (industrial gases) and asked.

Even if you have a 5000 psi tank and you blow out the valve, the tank won't explode. The cilinder will shoot away throught anything you put in it's way, but it will not explode.

This explosion was most likely by oxygen and some type of oil/grease in contact with the valve or close to the tank.

dagodiver
05-14-2007, 09:45 AM
Ok, kept on thinking why the tank exploded, and things were not very clear to me so I went out to the family business (industrial gases) and asked.

Even if you have a 5000 psi tank and you blow out the valve, the tank won't explode. The cilinder will shoot away throught anything you put in it's way, but it will not explode.

This explosion was most likely by oxygen and some type of oil/grease in contact with the valve or close to the tank.


I still dont agree with the explosion. I think it was a VERY rapid release of a compressed gas. If there was enough fuel laying around to make an explosion I believe alot more stuff would be damaged. A few drops of oil wont make it.
Oxygen is only that. Everything looks oxidized in the pictures not burned.
BIG difference.



Dago.

kaborkian
05-14-2007, 11:31 AM
I still dont agree with the explosion. I think it was a VERY rapid release of a compressed gas. If there was enough fuel laying around to make an explosion I believe alot more stuff would be damaged. A few drops of oil wont make it.
Oxygen is only that. Everything looks oxidized in the pictures not burned.
BIG difference.



Dago.

I totally agree. There was no evidence of fire. Rapid de-compression and re-compression of the immediate area around the valve will cause EXTREME heat, but not necessarily fire. Had a fire occured, the vice, bench, bottle, wrench, person holding the wrech, etc would have all melted.

The problem was his methodology. He unscrewed a thread fit under pressure. Threads are not designed for relative motion while under load. Essentially, by unscrewing the valve while under pressure, he applied a HUGE side-load to the threads, causing them to strip out and allowing the valve to be liberated from the bottle at a high velocity. The resulting force ripped the vice apart and broke the bottle. Had it not been in the vice in the first place, it would have become a rocket like in the mythbusters episode, and probably not come apart.

Still a very sobering set of pictures. I think about that stuff when I'm partial-pressure blending Nitrox. You never know just how slow or fast you can transfer O2 without issues...

AlexF
05-14-2007, 11:59 AM
There was an explosion within the tank, it was blown to pieces.

You can unscrew, hammer or do anything to a gas cilinder valve and it will shoot back, but it will not explode.

I will try to find out if our partners in the US (Air Products) has knowledge of this case and will post it.

dagodiver
05-14-2007, 12:06 PM
There was an explosion within the tank, it was blown to pieces.

You can unscrew, hammer or do anything to a gas cilinder valve and it will shoot back, but it will not explode.

I will try to find out if our partners in the US (Air Products) has knowledge of this case and will post it.



Alex,
I respectfully disgree with you on the "within the tank".
I have seen "exploded" tanks that are nothing more than a catastrophic failure during rapid decompression.

Dago.

markZ
05-15-2007, 04:58 PM
No vid, but an interesting story with photo':

http://www.irishmansoftware.com/fill_your_own_tanks.htm

WonderBoy
05-15-2007, 07:03 PM
It says "there were reports of him boosting tanks to 4500 psi of PURE OXYGEN"
How can that be? I thought Oxygen cylinders weren't filled any higher than 2250?

bgbill
05-15-2007, 07:33 PM
It says "there were reports of him boosting tanks to 4500 psi of PURE OXYGEN"
How can that be? I thought Oxygen cylinders weren't filled any higher than 2250?

Haskel

dagodiver
05-15-2007, 07:51 PM
It says "there were reports of him boosting tanks to 4500 psi of PURE OXYGEN"
How can that be? I thought Oxygen cylinders weren't filled any higher than 2250?

WOW nice stuff Z.!


Like Bret said Haskel.
I always have a few tanks with 3000psi of O2 in them.


Dago.

WonderBoy
05-16-2007, 07:47 AM
Thanks for the info!

FredT
05-16-2007, 09:30 AM
"Dayum! But I don't get WHY it exploded? What did he do wrong?"


O2 escaping through the threads as soon as the seal is broken will be moving at near sonic velocity through the restriction. This will cut through the protective oxide on the tank and allow the dynamic heat rise of the escaping gas to ignite the aluminum in the thread area. Once ignited the aluminum will burn very rapidly and in both directions from the ignition point..

One of the primary components of many class "c" explosive devices is finely divided aluminum. Given the correct conditions it burns really well!

BTW those valves are designed so there are two methods the valve can be safely disassembled with pressure in the tank if the stem or seat malfunctions. The disassembly method used in this example is NOT one of correct ways to do it!

FT

dagodiver
05-16-2007, 11:37 AM
"Dayum! But I don't get WHY it exploded? What did he do wrong?"


O2 escaping through the threads as soon as the seal is broken will be moving at near sonic velocity through the restriction. This will cut through the protective oxide on the tank and allow the dynamic heat rise of the escaping gas to ignite the aluminum in the thread area. Once ignited the aluminum will burn very rapidly and in both directions from the ignition point..

One of the primary components of class "c" wexplosive devices is finely divided aluminum. Given the correct conditions it burns really well!

BTW those valves ar designed so there are to methods the valve can be safely disassembled with pressure in the tank if the stem or seat malfunctions. The disassembly method used in this example is NOT one of correct ways to do it!

FT



Thankyou.!
I was wondering when you were going to get to this.!


Dago.

Don-in-Japan
05-17-2007, 02:03 PM
The damage reminds me of my first experience with split rims when I was 12. Ouch..!