dive tank air time

[mnz]

Hello all.
My question is this.
How long does it take to empty an air tank at surface pressure if the valve was only releasing at aproximatly 180 psi.
many many thanks in advance.
matt
ps 0 hours dive experience.

 

[Compressor]

If the tank has only 180 psi in it, just a few minutes.

 

[mnz]

Thank you but I didn't really explain that question properly. So let's sayit's a 12 litre tank at 3500 psi. Releasing at 180 psi.

 

[Pinecube]

I found the post where somebody tested draining tanks using different methods at different depths.
Original post is here: "Plugged end" of high pressure (gauge) hose

This was the result of draining AL80 on the surface using various methods. I think the closest to what you're asking for is #3, a failed LP hose.

1. Failed Burst Disk = 72 seconds
2. Failed HP Hose = 22 minutes
3. Failed LP Hose = 83 seconds
4. Free Flow High Performance Regulator = 255 seconds

 

[loosenit2]

This appears to be a real activey simple math problem. You did not specify if the rate of loss was 180 psi per minute or per second.

If a tank is loosing 180 PSI per min and the tank capacity is 3500 PSI the tank would empty in 19.4 minutes (3500/180).

If the tank is loosing 180 PSI per sec and the tank capacity is 3500 PSI the tank would empty in .324 minutes (3500/180*60).

I’m not sure that is answering your question though, I think you have a different question in mind and perhaps need to rephrase? This simplistic answer is based on you asserting that you knew the rate of loss of the tank was 180psi per min/sec.

 

[mnz]

Ah that's it you have answered my question perfectly.it was really the math of air pressure versus the release pressure at a particular rate.thank you all very very much.

 

[saxman242]

It depends on the size of the opening to the tank. Can you provide some context as to what you're trying to work out?

 

[MaxBottomtime]

 

[Steve_C]

Perhaps I am dense but to me 180 psi is the pressure exerted by the outflowing Air. It does not seem to me to define the air loss without knowing the leaking valve/hole. I can visualize a large tank, with a little leaking value and the pressure in the outflow was 180 psi. Note the numbers above where a leaking HP hose drains the tank more slowly than a LP hose because of the different hose interior diameters. Just knowing the psi does not answer the question. We need more data from the OP.

 

[Bob DBF]

2. Failed HP Hose = 22 minutes
3. Failed LP Hose = 83 seconds

I would assume that was burst, as I have completed a dive with a failed HP hose that was just bubbling through the cover, and a leaking LP hose at the connector, not both at the same time. I would use neither again, but the failure was much less threatening. There are many different failures, most are minor.

I had a good LP hose burst when the IP went high on an upstream second with no over pressure relief, alternates were not used so no downstream second for relief. It was quite exciting as I sorted it out. Only occourance I've had of a burst hose.




Bob