[Finless]

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Would someone be kind enought to save me the trouble of working out the method calculating the final pressure after decanting from one cylinder into another.

Example - twin 10s with 60 bar left. Decant from a 12 ltr single with 230 bar. What will the final equalized pressure be.

Assume constant temperature in all cylinders before and after the decanting.

 

[Mary]

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<font color='#F52887'>I don't know the answer but when someone does I'll be very interested in knowing

 

[Finless]

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Quote[/b] (Mary @ April 07 2004,10:56)]I don't know the answer but when someone does I'll be very interested in knowing

Mary,

Thank you very much for that helpful comment.  

Bryan

 

[Snash]

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Dec is the smaller one (not Ant, as would make sense).

Or have I got them the wrong way round  

Simon

 

[440634]

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<font color='#32CD32'>If the manifold is open, you'd end with 124bar in everything.

If you close the manifold and dedant into one, then decant into the other and then open the manifold, you'd end with 132bar in the twin 10s and 111bar in the 12.

Juz

 

[Nath]

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<font color='#8D38C9'>theres was a thread with calcs not long ago

bee right back...


...

thread

 

[Helen F H]

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<font color='#000080'>they are both Geordies, one of my mates hit one of them a few years ago

 

[Nath]

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Quote[/b] (Porg @ April 07 2004,11:22)]they are both Geordies, one of my mates hit one of them a few years ago

<font color='#8D38C9'>fair play

 

[Mary]

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Quote[/b] (Finless @ April 07 2004,11:05)]Thank you very much for that helpful comment.  

<font color='#F52887'>I aim to please  

 

[Finless]

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Quote[/b] (beanie @ April 07 2004,11:11)]theres was a thread with calcs not long ago

bee right back...


...

thread

Well done, that man.

 

[Driftwood]

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<font color='#0000FF'>(Vol 1 * Pressure 1) + (Vol 2 * Pressure 2)
                 Total volume

Should be self explanitory. In your case it is ((2*10 (twinset vol) ) * 60) + (12 * 230) / 32 =  1200 + 2760 / 32 = 123.75 Bar

 

[Diving Dude]

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Bryan,

l've worked out a spreadsheet on which you can start off with any size tank with any pressure and decant either a 230 bar 15 or 12 which gives the final pressure.

l'll e-mail it to you.

 

[Paul Oliver]

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Howard

Can i have one of those as well please

Paul

 

[ANDY 64]

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<font color='#0000FF'>Paul........

NO, coz i can't

 

[Fathoms Down]

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I've bunged a simple Excel chart which allows you to enter your tank's volume and the estimated equalized pressure you would get if you whipped it from some of the more popular filling cylinders. Its not perfect as it uses the ideal gas laws but it may be a handy kind of thing to laminate and keep in your kit bag. However, I should point out that, as far as I am concerned, its for interest only; if you blow yourself up as a result of using it then thats your problem (but please let me know so we can post it on the board and have a good laugh at your expense  

).

The sheet can be found on my largely empty and pointless web site.

 

[440634]

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<font color='#32CD32'>Nick,

Might be worth 'unlocking' the pressure cell of the decanting cylinder, afterall, I might be topping my twins from a 15l at 210 bar. (not 232).

Juz

 

[Fathoms Down]

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Oops, I thought I had done that. I'll get that sorted out and a new one posted. I'm pants with Excel