oxygen-impermeable serving lines

[kevink]

From Kegland:

"Outter Barrier - The outter barrier has accurately extruded tolerances and made from an EVA material. It also seals well when used with various John Guest, DuoTight or other push in fittings. The outter barrier gives the tubing excellent kink resistance so the line is able to bend around a tight radius without kinking. "

"Inner Barrier" - The inner barrier is made from a proprietary polymer that has excellent gas barrier. The significantly better barrier properties means your beer is better protected from oxygen and also has a better barrier to CO2 loss."

EVABarrier 4mm(5/32) x 8mm(5/16) Double Wall EVA (12meter Length in Bag) Beer Line / Gas Line

 

[day_trippr]

The EVA layer is the gas barrier layer. The liner is only there because EVA is water-permeable and cannot have direct contact with water-based solutions. If they made gas-only EVA line they could forgo the liner completely, provided the gas is guaranteed water-free. I have no idea what the inner liner is made of.

Based on what I've seen I do not believe that is correct...

Cheers!

 

[AlexKay]

No, the partial pressure gas laws ensure it doesn't actually matter what gas or what pressure is inside the tubing (except for oxygen itself).
To the degree that the tubing prevents molecular ingress, oxygen will find its way in, independent of other gas pressure influences.

So it's all about slowing ingress, period, and EVAbarrier right now is the best you can get in a highly usable form...

Cheers!

This is a (completely true) statement about equilibrium: eventually, you will have the same partial pressure of oxygen inside and outside, regardless of the CO2 pressure.

Equilibrium doesn’t necessarily tell you anything about kinetics, and I suspect that the CO2 absolutely matters here — it will take much longer for oxygen to traverse the pore network when that network is full of CO2.

 

[Jayjay1976]

We're still talking about homebrewed beer aren't we? RDWHAHB.

 

[Northern_Brewer]

Does anyone actually know what the "proprietary" inner layer is? I don't understand why vendors don't use Teflon lined tubing for beer and gas lines.

Price maybe? The Valpar lines use nylon.

This is a good blog post on the subject from a pro.

 

[day_trippr]

That post actually seems rather content free...

Cheers!

 

[Cavpilot2000]

I too use 4mm EVA Barrier lines for my beer and 5mm for gas. The 4mm fits over a 1/4" barb if you soak it in hot water for a few seconds and use something to spread it (I use a nail set).
With the 4mm tubing you don't need much length (my beer lines are about 3-3.5 feet long.

 

[Cavpilot2000]

that stuff is super slick on the inside so its restriction is less. you're gonna need much longer coils to get the same amount of restriction.

that said, they have three different sizes, and you can go down in size to generate more restriction.

Not really. I use the 4mm on 1/4" barbs and my beer lines are about 3'6" long. That definitely doesn't fit into the "need much longer coils" theory.

 

[SanPancho]

Not really. I use the 4mm on 1/4" barbs and my beer lines are about 3'6" long. That definitely doesn't fit into the "need much longer coils" theory.

Reviewed the recommended lengths for each diameter? Ranges from 5 to 6 feet at 4mm to 20-25ft for 6mm which is not quite 1/4”. But 1/4” vinyl is usually good for 15 to 20 ft. That’s a longer length for a slightly smaller diameter.

 

[Cavpilot2000]

Reviewed the recommended lengths for each diameter? Ranges from 5 to 6 feet at 4mm to 20-25ft for 6mm which is not quite 1/4”. But 1/4” vinyl is usually good for 15 to 20 ft. That’s a longer length for a slightly smaller diameter.

Ah, I see where you got that then. But in reality, I don't think anybody is using 6mm for beer lines with EVA, everyone I've talked to are using 4mm (a tough but doable fit on 1/4" barb) or 5mm (the recommended size for 1/4" barb).

My point is with the OP worried about how to stash long line runs, it is irrelevant with a smaller tube (again, I have 3' to 3'6" lines with 4mm).
In the interest of full disclosure, I am running flow control ball lock QD's, which restrict flow even more, but are great for that occasional keg that gets over-carb'd. Anyway, if your concern is what to do with long lines, you can eliminate that issue pretty easily.

 

[SanPancho]

you talking about the flow control qd's from the same group? i think williams sells them. i know somebody posted about the recently (you?). but havent seen a bunch of reviews yet. but between the two you're down only 3ft? thats pretty sweet.

my experience with this stuff is that it did not want to expand and slide over larger barbs/fittings. maybe we just didnt get it hot enough. we definitely didnt have anything like a reamer to help expand it. maybe those two are the key. daytripper seems to say you can heat that sucker up and get a 5mm ID over a 3/8 barb which should be at least 9mm. im skeptical, but once i get off my ass and find that damn heat gun i'll see what's what.

in any case, i dont have a draft tap setup, i just use picnic taps. so im all in for the flow control qds and a few feet of tubing if that cleans up my cooler and stops the oxidation.

 

[stickyfinger]

as the OP, I heartily endorse the direction of this thread! ha ha.

I use the 4mm ID EVAbarrier exclusively and I agree it is awesome stuff. Super easy to work with, bends and coils like a dream, and I get pretty much perfect pours @ 12psi with 6'6" lines. they coil up neatly and can sit on top of the keg in between the handles. You would have to leave the tap sitting unused for an extended period of time for oxygen ingress to cause any noticeable change in your beer, and even in that case the tiny inner diameter means you would waste maybe an ounce of beer at the most. If that isn't good enough for you then go ahead and hard pipe your setup with stainless tubing and flare fittings. That should work out well.

 

[stickyfinger]

here is a SS flow control quick disconnect. I had never heard of that. that would be awesome for putting on a keg and attaching a tap right to it for serving at parties with no beer line, no? not that there will be any parties in the forseeable future.

Keg Land Stainless Flow Control Ball Lock Threaded Fitting

 

[day_trippr]

Reviewed the recommended lengths for each diameter? Ranges from 5 to 6 feet at 4mm to 20-25ft for 6mm which is not quite 1/4”. But 1/4” vinyl is usually good for 15 to 20 ft. That’s a longer length for a slightly smaller diameter.

I don't know where you get the idea that 1/4" PVC tubing is "good for 15 to 20 ft" as that diameter requires a lot closer to 40 feet assuming typical kegerator conditions and a 12 psi CO2 pressure.

Try playing with the only line length calculator worth using: Determining Proper hose length for your Kegerator

4 mm is 0.1574798"
5 mm is 0.1968498", a slightly wider bore than 3/16" so one would expect slightly longer lengths to match standard PVC performance.
6 mm is 0.2362198", a bit skinnier bore than 1/4" so one would expect a bit shorter lengths to work vs PVC...

Finally, as always, use caution accepting line length vs performance claims at face value. I've seen ridiculous configurations that were claimed to provide "perfect pours"...

Cheers!

 

[day_trippr]

here is a SS flow control quick disconnect. I had never heard of that. that would be awesome for putting on a keg and attaching a tap right to it for serving at parties with no beer line, no? not that there will be any parties in the forseeable future.

Keg Land Stainless Flow Control Ball Lock Threaded Fitting

There are problems with those flow control connectors: they induce a minimum resistance that might be too high for many configurations...

Cheers!

 

[Jayjay1976]

Better to create natural backpressure via the flow resistance of a small diameter or longer tubing to prevent CO2 breakout rather than a single point of restriction. I would expect the venturi effect to cause some foaming so I can't imagine you could connect a faucet directly to the disconnect. Maybe it works with a super low serving pressure, 3-4 psi.

Disclaimer: I'm new to kegging.

 

[SanPancho]

I don't know where you get the idea that 1/4" PVC tubing is "good for 15 to 20 ft" as that diameter requires a lot closer to 40 feet assuming typical kegerator conditions and a 12 psi CO2 pressure.

Try playing with the only line length calculator worth using: Determining Proper hose length for your Kegerator

4 mm is 0.1574798"
5 mm is 0.1968498", a slightly wider bore than 3/16" so one would expect slightly longer lengths to match standard PVC performance.
6 mm is 0.2362198", a bit skinnier bore than 1/4" so one would expect a bit shorter lengths to work vs PVC...

Finally, as always, use caution accepting line length vs performance claims at face value. I've seen ridiculous configurations that were claimed to provide "perfect pours"...

Cheers!

1/4 vinyl is 0.65lb to .85 resistance per foot. depends on which brand, wall thickness.
12psi, minimal height difference, and you're at anywhere from 14-15 to 18-19feet. add a foot or two for safety.

so keep your calculator. we were taught to do the math. it never fails.

 

[SanPancho]

the thread referred to above about the kegland flow control disconnects had one guy who got them to work with his faucets connected directly to the qd.

he ended up using a foot of tubing since he said it was super touchy and hard to dial in with direct connection. the one foot of hose he used made it way easier to dial it in permanently. that was the general gist, if not his exact post.

 

[day_trippr]

1/4 vinyl is 0.65lb to .85 resistance per foot. depends on which brand, wall thickness.

cough<bs>cough
That's ridiculous - where did you get that number?

so keep your calculator. we were taught to do the math. it never fails.

hahahahaha! Right - you're off to a great start with that insane resistance figure.

I'll stick with the work of an actual physics phd, thanks...

Cheers! (Like I said earlier, I've seen ridiculous claims. Thanks for proving my point so quickly! )

 

[SanPancho]

It's ethylene-vinyl-acetate (a.ka. EVA).

Teflon would be even better as far as oxygen permeability goes but the tubing would be stiff as hell to the point of being impractical as beverage line because of the huge bend radius.

happened to find a packing slip at the bottom of box with tubing scraps in it, says right under the EVA tubing line item - has a CA prop 65 warning for chemicals including Di-n-butyl phthalate (DBP).

 

[SanPancho]

cough<bs>cough
That's ridiculous - where did you get that number?



hahahahaha! Right - you're off to a great start with that insane resistance figure.

I'll stick with the work of an actual physics phd, thanks...

Cheers! (Like I said earlier, I've seen ridiculous claims. Thanks for proving my point so quickly! )

show these to your phd clown.

https://www.kegworks.com/blog/determine-right-pressure-for-your-draft-beer-system/
https://www.homebrewcon.org/wp-content/uploads/presentations/2008/Daniels_Perfect_Pint.pdf
https://www.micromatic.com/1-4-inch-id/1-4-inch-id-clear-vinyl-hose-priced-by-the-foot-548c
Cough. Cough.

 

[day_trippr]

You're not helping your case here, and this is why we turn to people that actually know how things work, rather than people who comes across some random number.

The only way to actually come up with a useful resistance figure is to know the conditions - like the pressure used for a given flow rate.

Saying "this tubing has a flow resistance of .85 pounds per foot" means literally ZERO without knowing the pressure used.

Similarly, the oft-stated "2-3 psi per foot" canard historically given for 3/16" ID tubing was equally "wrong" from the jump because it is context-free - just like your .85 psi per foot - and thus is the source of probably half the "Help! My pours are all foam!" threads here.

At 12 psi, the resistance per foot of ANY tubing is going to be dramatically less than the same tubing spec just below burst pressure conditions. And I guarantee you that for 1/4" ID PVC driven at 12 psi your .85 psi/foot number is ridiculous...

Cheers!

 

[day_trippr]

btw, don't just point somewhere and go "See!" because you just make yourself part of the problem.

This issue has existed since someone completely misinterpreted some tubing performance spec and completely ignored the part that said "in this pressure range typically used for beverage dispensing expect to see this range of equivalent resistance". Literally 99% of "guidance" provided on the internet followed the same canard like sheep - including that stupid Micromatic Draft Beer Quality handbook.

It's everywhere - except for one place that gets it right...

Cheers!

 

[doug293cz]

happened to find a packing slip at the bottom of box with tubing scraps in it, says right under the EVA tubing line item - has a CA prop 65 warning for chemicals including Di-n-butyl phthalate (DBP).

DBP is a liquid, so it can't be used as a liner. It is used as a plasticizer in other polymers to make them more flexible. It could be used as a plasticizer in the outer or inner layer, or it could just be a minor contaminate left over from manufacturing the other polymers used.

Brew on

 

[SanPancho]

You're not helping your case here, and this is why we turn to people that actually know how things work, rather than people who comes across some random number.

The only way to actually come up with a useful resistance figure is to know the conditions - like the pressure used for a given flow rate.

Saying "this tubing has a flow resistance of .85 pounds per foot" means literally ZERO without knowing the pressure used.

Similarly, the oft-stated "2-3 psi per foot" canard historically given for 3/16" ID tubing was equally "wrong" from the jump because it is context-free - just like your .85 psi per foot - and thus is the source of probably half the "Help! My pours are all foam!" threads here.

At 12 psi, the resistance per foot of ANY tubing is going to be dramatically less than the same tubing spec just below burst pressure conditions. And I guarantee you that for 1/4" ID PVC your .85 psi/foot number is ridiculous...

Cheers!

interesting how the term "insane" doesnt seem to apply to you. the brewers association of america, filled with educated folks (even phds!!), put out a draft quality manual. tubing specs, with those calculations, work. everwhere. every time. six days and sunday. and somehow you're 1000% sure its wrong, i.e. that literally decades of effective usage has all been..... a fluke?

and yet im the one making insane statements? ok. i see. guy on the internet vs literally the entire brewing industry. yessir, that's an easy choice.

so i tell you what- how about we agree to disagree?

you go on believing that you and your phd buddy and the magical calculator are the only ones in this wicked land who know the secret physics.

i'll stick with the specs and math that have produced perfect pours the first time, in our bars and restaurants and brewpubs, the ones the AB-educated local draft techs use, the ones that the american Brewers Association uses, that manufacturers use, that world famous local beer bars use, and which havent ever failed us.

 

[day_trippr]

And yet, the consistency of favorable resolution to the literally hundreds of folks that came to HBT with pour problems after switching to the advised one foot of 3/16" ID tubing per psi defies all of that. Time after time after time.

Whatever, I've beaten this drum enough that a discerning reader will hopefully avail themselves of the tools to success and avoid the pratfalls that your conventional wisdom sets...

Cheers!

 

[Cavpilot2000]

you talking about the flow control qd's from the same group? i think williams sells them. i know somebody posted about the recently (you?). but havent seen a bunch of reviews yet. but between the two you're down only 3ft? thats pretty sweet.

my experience with this stuff is that it did not want to expand and slide over larger barbs/fittings. maybe we just didnt get it hot enough. we definitely didnt have anything like a reamer to help expand it. maybe those two are the key. daytripper seems to say you can heat that sucker up and get a 5mm ID over a 3/8 barb which should be at least 9mm. im skeptical, but once i get off my ass and find that damn heat gun i'll see what's what.

Yes, those same flow control QDs (bought from Williams). I went that route with my kegerator instead of FC faucets. They are awesome, but they do impose some additional restrictions, which is only a problem if you need to run really long lines (like storage in the basement with serving upstairs). In something like a kegerator, it's perfect because even with those FC QDs open full-throttle, I only need 3 feet of 4mm beer line at about 12 PSI.
To fit the 4mm over a 1/4" barb (I doubt it would go any bigger, especially not 3/8" with 4mm), I use hot water and a nail set. The nail set is simple and cheap and has a graduated taper that I use to expand the tube until it slips over the 1/4" barb.
And yes, having 36-42 inch beer lines is awesome. No excess, no coils of tubing, no fuss.

 

[Bobby_M]

show these to your phd clown.

https://www.kegworks.com/blog/determine-right-pressure-for-your-draft-beer-system/
https://www.homebrewcon.org/wp-content/uploads/presentations/2008/Daniels_Perfect_Pint.pdf
https://www.micromatic.com/1-4-inch-id/1-4-inch-id-clear-vinyl-hose-priced-by-the-foot-548c
Cough. Cough.

Well, with a domain like Kegworks, a blog post must be right. Over the last 10 years on HBT, there's probably been over 1000 new threads along the lines of "help, beer foamy". In every case where the OP finally listened to the people suggesting they are using the wrong line diameters and/or lengths and finally put the longer line on came back and reported success. Regarding all the people that report personal experience, failures and successes with different line types and lengths, what motive would they have to mislead on a forum? As a vendor for 10 years, I've demoed 20+ different tubing brands. I've sold over 500,000 feet of tubing, sometimes 10ft at a time. Most of those times were someone replacing a crusty line on commercial kegerator and when I told them they needed 10 feet to prevent foaming they ALWAYS say, "yeah, I just thought home kegerators were foamy". Do you want to get it right the first time or do it your way and suffer the foam lest you have to admit defeat rebuy in shame?

 

[SanPancho]

Well, with a domain like Kegworks, a blog post must be right. Over the last 10 years on HBT, there's probably been over 1000 new threads along the lines of "help, beer foamy". In every case where the OP finally listened to the people suggesting they are using the wrong line diameters and/or lengths and finally put the longer line on came back and reported success. Regarding all the people that report personal experience, failures and successes with different line types and lengths, what motive would they have to mislead on a forum? As a vendor for 10 years, I've demoed 20+ different tubing brands. I've sold over 500,000 feet of tubing, sometimes 10ft at a time. Most of those times were someone replacing a crusty line on commercial kegerator and when I told them they needed 10 feet to prevent foaming they ALWAYS say, "yeah, I just thought home kegerators were foamy". Do you want to get it right the first time or do it your way and suffer the foam lest you have to admit defeat rebuy in shame?

the point of the links are citations/references showing resistance of 1/4 vinyl tubing as .65 to .85. Exactly as I stated. Nothing more

 

[doug293cz]

the point of the links are citations/references showing resistance of 1/4 vinyl tubing as .65 to .85. Exactly as I stated. Nothing more

The problem with your references is they don't show where the resistance numbers came from. They don't reference an authoritative source. Fluid Dynamics is settled and well understood science. If you are going to argue against physics, you better have some very bullet proof data to back you up. You haven't shown that.

Brew on