Beer Line Length and Pressure Calculator

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Bearcat Brewmeister

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Just finished this one. It uses a few formulas found on the Internet to calculate the head loss for different types of beer line and shanks (or cobra tap). You enter the items at the top: beer style, temperature range you want to see, beer line inside diameter, shank bore, height from center of keg to tap, and distance from keg output to shank. The table will then show the range of CO2 volumes that are appropriate for the style selected across the top and temperature down the side. For each temperature/CO2 volume combination, a beer line length and properly balanced psi setting to carbonate the beer and push it through the given length beer line are displayed.

Let me know how it works for you and if you have any ideas for improvements.

Beer Line Length and Pressure Calculator
 

Drunkensatyr

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Sorry, don't have excel otherwise I would love to give you feedback. Sounds like a great project though.
 

Thalon

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This is a very nice tool, but I'm slightly confused on a couple of the settings. What exactly is Height from Keg Center to Tap? Is it from the pickup tube at the bottom center of the keg to the outlet of the keg, or something different? And what exactly is Distance from Beer Out Connector to Shank? The way it's worded it almost sounds like the length of beer line, but that's one of the outputs of the spreadsheet. Can someone maybe post a picture that can illustrate the distances? That would help a TON.
 
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Bearcat Brewmeister

Bearcat Brewmeister

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Height from keg center to tap is the height differential that the beer has to overcome on average to get from the keg to the tap (#1 in diagram). When the keg is full, it is from roughly the top of the keg to the tap. When it is just about empty, it is from the bottom of the keg to the tap. Using the center of the keg just averages the two scenarios of full keg and empty keg. Using this estimate is obviously off by the most when the keg is either full or almost empty, but beer only loses roughly 0.5 psi of pressure per foot it is moved against gravity. Since a keg is roughly 2 feet tall, measuring from the center makes you a half pound too much pressure when full and half pound too low when almost empty - not a big issue.

Distance from keg output to tap (#2) is there strictly as a constraint. Without it, the calculator could, given the right set of inputs, tell you to use 6 inches of line when the distance from your keg outlet to your tap is 12 inches. This can definitely be an issue with Brittish and Scottish beers that require low pressure but all you have is restrictive 3/16" line or if you have to have your beer line travel some horizontal distance.

 

dirtymartini

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Bearcat Brewmeister said:
Just finished this one. It uses a few formulas found on the Internet to calculate the head loss for different types of beer line and shanks (or cobra tap). You enter the items at the top: beer style, temperature range you want to see, beer line inside diameter, shank bore, height from center of keg to tap, and distance from keg output to shank. The table will then show the range of CO2 volumes that are appropriate for the style selected across the top and temperature down the side. For each temperature/CO2 volume combination, a beer line length and properly balanced psi setting to carbonate the beer and push it through the given length beer line are displayed.

Let me know how it works for you and if you have any ideas for improvements.

Beer Line Length and Pressure Calculator
Nevermind..
 

McKBrew

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I am using your calculator for my set-up. Has everything I need in one spot.
 
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Bearcat Brewmeister

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Thanks for saying so. It hasn't failed me yet. A lot of folks use a set line length, then adjust pressure until it flows right. That is back asswards. You should set your pressure to the correct serving pressure for the beer style at the particular temperature you are at, then size your line (length AND diameter) to scrub off all of the excess pressure such that your beer flows correctly.

The other important thing is to make sure that the line feeds upward in all spots. The shanks tend to be warmer that the interior of the fridge, so the beer in contact with them when it is just sitting tends to warm and CO2 breaks out of solution. If the line feeds down to the shank, even a bit, the bubbles run back towards the keg. This causes a rush of beer, then foam, then beer, which ends up with a foamy glass.
 

Boerderij_Kabouter

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A lot of folks use a set line length, then adjust pressure until it flows right. That is back asswards. You should set your pressure to the correct serving pressure for the beer style at the particular temperature you are at, then size your line (length AND diameter) to scrub off all of the excess pressure such that your beer flows correctly.
This thread and tool are great! My one question concerns the different lengths of beer line. Do you just keep multiple lengths on hand and switch them out as appropriate? For example, do you keep, 6', 8', 10', and 12' lengths handy and just switch them out as necessary?

Thanks for the clarification!
 

StunnedMonkey

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Is it just me, or does anyone else find that these calculators drastically under-calculate the required length? I use the standard 8.9 cf ft whirlpool keezer at 38 degrees, and keep my regular brews at 10 psi. All these calculators call for anything from 4 to 6 feet (depending on which one you use) of 3/16 inch tubing. But in practice anything less than 10 feet isn't usuable. I'd suspect that my regulator is off or something, but the beer is perfectly carbed.

I just keep all my lines at 10 ft.
 
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Bearcat Brewmeister

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Just finished this one. It uses a few formulas found on the Internet to calculate the head loss for different types of beer line and shanks (or cobra tap). You enter the items at the top: beer style, temperature range you want to see, beer line inside diameter, shank bore, height from center of keg to tap, and distance from keg output to shank. The table will then show the range of CO2 volumes that are appropriate for the style selected across the top and temperature down the side. For each temperature/CO2 volume combination, a beer line length and properly balanced psi setting to carbonate the beer and push it through the given length beer line are displayed.

Let me know how it works for you and if you have any ideas for improvements.
I don't think I can edit a thread this old, so I will just add on to it - the original link has changed addresses, so here is the file:

View attachment Beer Line Length and Pressure Calculator.zip
 

WheeledGoat

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this thing kicks ass - i keep coming back to it. at first i was like "whaa? i can do the math, what's the big deal?" but then when it comes down to it, i'm just too damn lazy to go looking up the formulas and resistance for what diameter, etc...

after using it several times, i figured i'd drop a note of my appreciation.

muchos grassyass!
 

motobrewer

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ok, i'm confused. here are my inputs:

Porter; 34F to 44F, 5/16" beer line, 5" shank, 3/16" shank bore, 16", 6"

to get 2.2 volumes, the shortest length I get is 266" (22 ft) at 6.5 psi. is this right?
 

Shay

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ok, i'm confused. here are my inputs:

Porter; 34F to 44F, 5/16" beer line, 5" shank, 3/16" shank bore, 16", 6"

to get 2.2 volumes, the shortest length I get is 266" (22 ft) at 6.5 psi. is this right?
That should be. 5/16" is a big line. Most people use 3/16" line so there is more resistance in the line.
 

gauvinej

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New here and this tool looks amazing. But one question, is the temp in these calcs the temp the keg is at? What if you were to be running it through a cold plate and the keg was to stay around 55 or maybe higher, the setup will be in a basement where its around 55-60 degrees even during the summer? Thanks in advance.
 

nathan

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So does all this nice balancing apply to a stout tap running beergas?
 

nathan

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any chance I can get the password to unprotect it? I'd like to extend upwards with the volumes and temperatures to increase the size and range of the table (might go lower in volumes, too)
 
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Bearcat Brewmeister

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New here and this tool looks amazing. But one question, is the temp in these calcs the temp the keg is at? What if you were to be running it through a cold plate and the keg was to stay around 55 or maybe higher, the setup will be in a basement where its around 55-60 degrees even during the summer? Thanks in advance.
It is the temperature the beer is at. The gas needs to dissolve into solution.

So does all this nice balancing apply to a stout tap running beergas?
I don't think so.

any chance I can get the password to unprotect it? I'd like to extend upwards with the volumes and temperatures to increase the size and range of the table (might go lower in volumes, too)
Why would you want to go above 55F? The calculator is meant to be a tool to carbonate specific styles to their appropriate levels. Are there styles that I am missing that should be higher or lower than the table goes? It goes all the way down to 0.8 for a Scottish up to 4.7 for a Weizenbock.
 

nathan

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maybe I have an old one?
Mine is 34-44 and 2.2-2.8
I'll go back through the thread and see if I missed an update
 

nathan

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um. heh. Well I missed that some of those items were selections. I don't know why I used some as selections and not others without trying it. My goof!

I'm guessing that for something like an english bitter, at 40F, since that is below my threshold, I would need to push it with nitrogen so the partial pressure of 1.0 would mean a beergas pressure of 4.0

Does that sound logical?
 

nathan

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I've had a chance to balance and set up 3 kegs and they are pouring great using this.
 

OakLeaf

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It is very nice job!

Is it possible to to make version with temperature in Celsius, length in meters and pressure in bars ?

It will be very helpful for European users ;)
 

kcwcc

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It is very nice job!

Is it possible to to make version with temperature in Celsius, length in meters and pressure in bars ?

It will be very helpful for European users ;)
And Canadians too! Other than bar of course...psi rules here...and kilopascals are generally ignored too.
 

Mayday99

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Awesome, thanks!

Looks like I am going to need a long line for my Hefe this summer!
 
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