DIN Plugs in O2 Cylinders. Good Idea? Bad Idea?

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TheWetRookie

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The DIN plugs I have are plastic, thoughts on this type of plug please. I use them when my tanks are stored for a while to keep the dirt out.
 

fdog

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Plastic is bad. When pressurized it turns into high-speed plastic shrapnel. Usually embedding itself into a hand or hip when the valve is accidentally turned on.


All the best, James
 

DandyDon

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Sounds like an exterior protection of the valve would be best, a very good one.
 

Jax

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Plastic is bad. When pressurized it turns into high-speed plastic shrapnel. Usually embedding itself into a hand or hip when the valve is accidentally turned on.


All the best, James

?? My plastic plugs have a small rubber plug in them, so if there is pressure it blows the little plug out.
 

cool_hardware52

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I am keeping DIN plugs in everything for the same reasons. I don't see the amount of O2 trapped in a pressurized plug to be an issue. I always make sure the valve is firmly off before removing the DIN plug.

The change I plan to make. I will be moving to steel LP 45s for my O2 or maybe even one LP45 and one LP 19 with vendable plugs. 100% in a 40 cuft HP aluminum cylinder has always bothered me a bit. Especially when I stupidly leave them upright.

I tend to believe the cylinder material has very little to due with deco bottle explosions. There are literally millions of aluminum medical O2 cylinders in use today. My suspicion is the problems lie with the valves, and perhaps with the nature of the use.

Tobin
 

fdog

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Jax, you are correct, for small trickle leaks where the valve is only cracked and it's hissing like an anemic garden snake, the hole does nicely.

...Twist that valve open, though, and the volume will quickly overwhelm the tiny orifice. Then the pressure will build up until the plastic yields.


I will confess I didn't really believe this myself, until, using a rope and a full tank I removed all doubt...!


So my rule is: DIN plugs (go in the valve) are Stainless Steel, DIN caps (go on the regulator) are plastic.



All the best, James


PS There's a story about metal DIN caps that we don't need to go into. Suffice to say I KNOW they have to be plastic.
 

cavemn

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I tend to believe the cylinder material has very little to due with deco bottle explosions. There are literally millions of aluminum medical O2 cylinders in use today. My suspicion is the problems lie with the valves, and perhaps with the nature of the use.

Tobin

Just because it's done that way doesn't mean it's the best idea. Medical O2 I thought was kept at lower pressure. The valves are yoke style :0. Still an aluminum tank though.

My thoughts on LP steel is to keep the O2 at lower pressure but a similar volume. The Fabers will take 5000psi before blowing a disc or rupturing unlike an aluminum. They are also negative buoyancy when empty which should be better during deco.


Sent from my iPad using Tapatalk HD
 

PfcAJ

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I use lp steels for bigger cave dives to allow a relatively high volume a a low pressure. I rarely fill high pressure oxygen.
 

ajduplessis

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I tend to believe the cylinder material has very little to due with deco bottle explosions. There are literally millions of aluminum medical O2 cylinders in use today. My suspicion is the problems lie with the valves, and perhaps with the nature of the use.

Tobin

I tend to believe the problem lies with lack of knowledge/education. People also become complacent and neglect to excecute what they learned and take shortcuts. Equipment is not maintained according to best practices. The other side is that there are a lot of divers not qualified to use/blend/store O2.
 
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