Beer Line Length and Pressure Calculator - Page 8 - Home Brew Forums

 Home Brew Forums > Beer Line Length and Pressure Calculator

02-08-2011, 05:22 PM   #71
IrregularPulse
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Nov 2007
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Quote:
 Originally Posted by Josh1 Request a little patience for a newby: what is the volume of CO2? Is this the volume of my CO2 tank? If so, aren't compressed gasses typically measured in weight, not volume? Bottom line, it looks like a great tool, I'm just not sure how to use it because I can't figure out what my input should be for CO2 volume. Sorry for the novice questions...
Volume of CO2 is the amount of co2 dissolved in solution (beer). AKA, an English Mild will have less volumes than an American light Lager. AKA less carbonation.
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02-08-2011, 10:17 PM   #72
Josh1
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Feb 2011
Amherst, NY
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Quote:
 Originally Posted by IrregularPulse Volume of CO2 is the amount of co2 dissolved in solution (beer). AKA, an English Mild will have less volumes than an American light Lager. AKA less carbonation.
Now that makes a whole more sense. Thanks for the help.

02-09-2011, 02:32 PM   #73
Anguslow
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Feb 2011
Milwaukee, WI
Posts: 10

Quote:
 Originally Posted by brian1 Now, for any of you that want the CORRECT length of hose based upon the principles of physics, mechanical engineering, and fluid mechanics... l = 1800*d/Q²*(p-0.44h), where: l = hose length (ft) d = hose ID (in) Q = flow rate (gpm) p = gage pressure of barrel (psi) h = height difference between middle of keg and faucet (ft) So if you've got a keg that you'd like at 12psi, the faucet is 2ft above the middle of the keg, you're using 3/16" tubing, and you'd like a flow rate of 0.7gpm: l = 1800*0.1875/0.7²*(12-0.44*2) = 9.5ft. (If the faucet is above the keg, h is positive; if the keg is above the faucet, h is negative.)
Perhaps I am having a complete brainfart, but I am not seeing the same results with this equation to the excel sheet. Plus, no matter how I order the equation, I do not get 9.5 ft. Using the equations available on other sites and entering the numbers provided above, it works out to be 3.7 ft to 4 ft (depending on the equation), which does match the excel sheet. What am I not seeing here? Can someone order the equation so that I can see what is in the numerator and denominator? Finally, there is a box after the 'd', is this a power (2, or 3 perhaps)?

Thanks.

02-09-2011, 03:08 PM   #74
CPooley4
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Apr 2009
Cottage Grove, Wisconsin
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I don't have the excel sheet in front of me and haven't looked at it in quite some time. However, my guess is the difference in flow rate. Most commercial setups plan for a flow rate of 1 gallon per minute which is a bit strong for most homebrew setups. Don't know if the excel sheet is set up with 1 gallon as the default or not, but more than likely that is the culprit.

I just ran a scenario based upon your number. When I use a flow rate of .7 I get 9.7 feet of line recommended. When I use a flow rate of 1 I get 4.75 feet of line recommended. That's assuming a diameter of .1875" line.

If you'd like you can shoot me your email via pm. I have a kegging calculator/how to built into my Brew Chart. It's not in my published version as I'm still upgrading, but I'd be willing to send it to you ahead of time so you can see what I'm talking about. My kegging calculator allows the user to control the flow rate and diameter of line so that they can dial into their system better.

cp
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02-21-2011, 08:07 PM   #75
mattd2
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Sep 2009
Papamoa, New Zealand
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Quote:
 Originally Posted by Anguslow Finally, there is a box after the 'd', is this a power (2, or 3 perhaps)? Thanks.
Shame that it has taken this long for someone to reply to your question about the "square" Angus. Since the formula is dealing with flows through a circular tube I would hazard a guess that the "square" is actually meant to be the symbol for squared (i.e. ^2 as you would enter it in excel). I think the formating of the forum probably didn't like using superscript and just blanked it out.
Hope it works out for you.

02-21-2011, 08:13 PM   #76
motobrewer
I'm no atheist scientist, but...
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Oct 2009
Thiensville, Wisconsin
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uh, CP responded to him within an hour

02-21-2011, 08:45 PM   #77
mattd2
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Papamoa, New Zealand
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Quote:
 Originally Posted by motobrewer uh, CP responded to him within an hour
Sorry, should of been more specific about the lack of reply for what the "square" in the formula was... hang on, my reply was specific about that...

Quote:
 Originally Posted by mattd2 Shame that it has taken this long for someone to reply to your question about the "square" Angus.

02-22-2011, 04:27 AM   #78
Rcole

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Jan 2011
Providence, Rhode Island
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Quote:
 Originally Posted by CPooley4 So say it that way without the unnecessary bs. He'd either agree and unprotect, offer the explanation above that he doesn't have the password anymore, or do nothing. Either way it's his work that he spent his time on and offered here for free for all to use. Those that don't like it or disagree with him can just make their own on their own time and offer it here for free for all to use. All the information is readily accessible to anyone that wants to take the time to do so.

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04-05-2011, 12:54 PM   #79
Bruin
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Jan 2010
Califon, NJ
Posts: 155

As another poster said, wow, gonna need a lot of line for my Heff! Regarding different lengths of lines for different styles: Changing line at the tower every time I change styles will be a PITA, so I'm planning on changing the length of the line by splicing on or removing a section of line to meet the line length requirement. I'm going to use some sort of nipple to make the connection. I assume I add the length of the nipple to the shank length? Being that it is a constriction at this point and offers resistance it should be taken into account, no?

08-05-2011, 04:31 AM   #80
dubuddaman
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Aug 2010
arizona
Posts: 3

Ok for every one on here doing this calculator, it isnt much but if you are doing a home brew/ kegerator a foot of restriction is alot. That equals 3 pounds of restriction in the system. So every 4" of 3/16" restrication line is equal to 1 pound of restriction in the line.
Also I do understand why you want to measure from the middle of the keg?? Where is the beer being sucked from?? Not the middle. It is being sucked from the bottom. Micro Matic is the only maker of these stems and valves, and you want to measure from the bottom of the keg to the faucet.