"long lines" orthodoxy

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BetterSense

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The normal advice is to use 10 foot lines so that when your beer is at serving pressure, it will pour slowly enough to not foam.

The idea is that the longer lines are introducing enough resistance to slow the flow down. If you reduced the pressure enough to slow the flow, the beer would be undercarbed.

It seems wasteful to use 10 feet of hose just for the purpose of slowing down the pour. Why not introduce resistance some other way? Why not, for example, pinch the center of the line slightly with a hose clamp or something? Why not crush the dip tube slightly to reduce the area?

I have seen the "expoxy mixing swizzle stick in the dip-tube" trick, but haven't tried it because I don't know where to get the swizzle sticks.

I'm thinking of trying an adjustable clamp so that I can just pinch the line to adjust the flow. Ideas?
 
Because beer line is expensive, has to be cleaned, and clutters up my kegerator. I only need 2 feet of line, max. Instead I have these big coils, 40 feet total, in my kegerator.
 
[...]I have seen the "expoxy mixing swizzle stick in the dip-tube" trick, but haven't tried it because I don't know where to get the swizzle sticks.

You can get them from Graingers.

I'm thinking of trying an adjustable clamp so that I can just pinch the line to adjust the flow. Ideas?

You should try it just to see what happens - which will most likely be lots of CO2 breakout in the line just beyond the clamp. Abrupt changes in flow rate will do that. Someone recently fighting foam problems discovered a cocked gasket inside a coupling. That's all it took to cause big problems...

Cheers!
 
Why not, for example, pinch the center of the line slightly with a hose clamp or something? Why not crush the dip tube slightly to reduce the area?

Did you ever go outside with the hose, and then pinch a portion of the flow to make water shoot harder and faster out of the hose? That's what is would happen if you narrowed the line in a place.
 
You should try it just to see what happens - which will most likely be lots of CO2 breakout in the line just beyond the clamp. Abrupt changes in flow rate will do that. Someone recently fighting foam problems discovered a cocked gasket inside a coupling. That's all it took to cause big problems...

Cheers!

What he said. You want laminar flow, not turbulent, and sudden changes in pressure can cause some of the CO2 to come out of solution. I went with ~12 ft lines on my system and I have no foaming problems. I can wait the extra couple of seconds it'll take to pour my glass, waiting for the foam to die down takes WAY longer.

I'm with the other posters above, beer line is fairly cheap (at least when talking about kegging components). Cut longer lines, coil them, and zip tie or velcro them. They should sit on top of the kegs without much problem. Good luck with it.
 
FWIW I tried the mixing sticks in my dip tube one time, and had some trub go up into the diptube and almost immediately clog the works up. To be fair, I had added some kind of fruit or something to that batch (but not in the keg), and the typical yeast sludge might not be as much of a problem, but I decided it wasn't worth the hassle of disassembling a full keg of beer just to fix it if it happened again.
 
There is an equation I was supposed to learn in college Physics class that I never could master...the flow rate is not going to change, and the speed of the beer coming out of the keg is not changing, just the orifice size...basically what Yooper said though...I think it would actually make the problem far worse.
 
I've had great luck with 5' lines on mine, same with my buddy's kegerator. I haven't had the need to go to 10' lines. All I do is adjust the pressure to what works and I'm good to go. Haven't had to worry about anything being undercarbed, and thats with homebrew as well as commercial.
 
There is an equation I was supposed to learn in college Physics class that I never could master...the flow rate is not going to change, and the speed of the beer coming out of the keg is not changing, just the orifice size...

You're right - it didn't take ;)

Restrictions reduce flow rate. That's why they're called "restrictions".

basically what Yooper said though...I think it would actually make the problem far worse.

That'd certainly be my bet...

Cheers!
 
i haven't got into kegging at all but from a physics point of view, if the objective of longer lines is to slow the flow of the fluid through the lines, larger diameter lines would achieve the same results. No? The whole Venturi effect thing. Now if this works for kegging, I know this not.
 
day_trippr said:
You're right - it didn't take ;)

Restrictions reduce flow rate. That's why they're called "restrictions".

That'd certainly be my bet...

Cheers!

I know, I know...physics was not my cup of tea. But it would cause turbulence, which is bad for a carbonated beverage, to say the least.
 
What about this product? It claims to work in beer lines to slow the flow and reduce foaming.

I found it here: http://www.chicompany.net/index.php?main_page=product_info&products_id=3146

Flow_Restictor.jpg
 
There is an equation I was supposed to learn in college Physics class that I never could master...the flow rate is not going to change, and the speed of the beer coming out of the keg is not changing, just the orifice size...basically what Yooper said though...I think it would actually make the problem far worse.

One of the possible equation you are referring to is the Navier–Stokes. Basically fluids will conserve momentum. Like Newton's second law. There would probably be a pressure loss from the pinch. They are called fitting or minor losses. The turbulence from the pinch, like other have mentioned, probably would not be good.

I think the magic of long lines is that friction or major losses reduce the pressure without the risk of causing turbulence.
 
Because beer line is expensive, has to be cleaned, and clutters up my kegerator. I only need 2 feet of line, max. Instead I have these big coils, 40 feet total, in my kegerator.

Well, on those three points:

Beer line is expensive? Looking at Northern Brewer, not quite the bastion of bargain homebrewing supplies, 3/16 ID beer line is about $2 a foot. A 10ft line isn't exactly going to break the bank. In terms of homebrewing purchases (especially compared to the rest of a kegging setup), this point just doesn't hold up.

Beer line has to be cleaned? Well, it has to be cleaned whether it's a 2ft line or a 10ft line, and the process is identical, this is another point that just doesn't hold up.

Clutters up your kegerator? OK, I'll grant that one. That extra line can be a bit of a hassle to manage, especially in a crowded kegerator.

But go ahead and use your 2 foot lines, and enjoy your pint glasses of foam. 8-10 foot lines are the conventional wisdom for a reason: they work.
 
i haven't got into kegging at all but from a physics point of view, if the objective of longer lines is to slow the flow of the fluid through the lines, larger diameter lines would achieve the same results. No? The whole Venturi effect thing. Now if this works for kegging, I know this not.

No. You want more restriction, not less.
 
There is no good argument for shorter lines presented so far that makes any sense. Put at least 8 feet of line and just enjoy your keg system. Avoid the advice of many experienced keggers and suffer the foamy consequences. Is it really worth the 4 bucks?
 
I've had great luck with 5' lines on mine, ...All I do is adjust the pressure to what works and I'm good to go.


That's the thing, most of us don't want to jack around with pressure until it pours right. That's sub equilibrium and whether you perceive any carbonation loss by the time the keg kicks is irrelevant. You are losing carbonation. Your standards for precise levels of CO2 are just looser.
 
Kind of in line with this topic. Does anyone notice a "lack' of carbination in the beer that sits in the beer line for a while (24 hours). It doesn't matter when you are filling a pint because the "de-carb'd" beer is only about 50ml in my lines which is what about 10% of a pint, but when I am sampling with my 200ml glass and only filling half way it is annoying having to pour that out (ok drink) that bit first to get to the carb'd stuff. Any ideas on why?
 
Most likely the beer lines are well above the bottom of the keg (where the dip tube fills from). And unless you have something to mitigate temperature stratification (eg: a stirring fan) that usually means the beer in the lines is warmer than the bottom of the keg, and warmer beer can't hold as much CO2...

Cheers!
 
That's the thing, most of us don't want to jack around with pressure until it pours right. That's sub equilibrium and whether you perceive any carbonation loss by the time the keg kicks is irrelevant. You are losing carbonation. Your standards for precise levels of CO2 are just looser.

Yes, and that's the thing.

If I had a kegerator with one keg and one regulator, maybe it wouldn't be too bad to jack around with the pressure too much.

But I usually have 5 kegs inside the kegerator, with a 4 way distributor on one line and one by itself. If I had to turn down the pressure to serve keg #1, but only wanted one glass and then wanted a glass from keg #4, but none from keg #2 that day, what do you do then? I'd have to turn down, purge, pour, turn up, etc. What a huge pain.

Instead, I have 10' lines (wish they were 12' for higher carb levels at times) and I never touch my regulator, my kegs, my lines, etc. I just put a keg in the kegerator and it stays there until it's empty and I swap it out. It's so easy, even I can do it!
 
Most likely the beer lines are well above the bottom of the keg (where the dip tube fills from). And unless you have something to mitigate temperature stratification (eg: a stirring fan) that usually means the beer in the lines is warmer than the bottom of the keg, and warmer beer can't hold as much CO2...

Cheers!

Good point, cheers! :mug:
 
These (Perlick Flow Control) faucets might work with shorter lines.

http://www.perlick.com/store/webcatalog2.php?catno=1&sectno=1&grpno=3

Disclaimer: I have never used these or even read a HBT thread about them. I have just seen advertisements.

I have them and they work great! I have lines about 4 to 6 feet and 15 psi.

One of my favorite features is that it is so easy to adjust them on the fly.
For example: before the first couple ounces of beer cool the faucet the beer will tend to be foamy, so you can start your pour with high restriction to minimize the foam. After the first couple ounces cool the faucet open it up to a speed that achieves the desired amount of head.

Some of my beers are more or less foamy than one another, so it is nice to control each independently with the lever on the faucet rather than replacing lengths of line or tweaking regulators.

My only complaint is that these faucets seemed to only be available in chrome plated rather than stainless... But maybe the price of stainless would have been beyond budget.
 
I bet a lot of folks would pay the price difference for stainless if the flow control solved all their dispensing woes without having to actually work them out through the usual means ;)

But, if the thread a month or two back about Perlick having major issues with 525 production was true (and they were replacing them with rear-seal faucets, no less!) I suspect they're a little too distracted to move some of the lower-volume models to stainless steel...

Cheers!
 
I have a friend who has those flow control perlicks. He said they are one of his favorite purchases and if had to get rid of everything save a few items, those perlicks would be at/near the top of the list.

The reason I'm looking at them is more to be able to serve higher carbonated beers without changing the lines out.
 
So, why do the Perlick faucets work, but adding a restriction to the line (by clamping) will not?

They're shaped to minimize turbulence, and there's less issue with downstream pressure drop since they're positioned right at the fluid exit. Simply clamping/kinking the line is going to create a lot of turbulence. You might be able to use a series of hose clamps in such a way that it minimizes the turbulence (mimicking the shape of a wind tunnel), but you'd still have to deal with the downstream pressure drop inducing CO2 breakout.
 
So, why do the Perlick faucets work, but adding a restriction to the line (by clamping) will not?

Check out their patent filing for it, there's a lot going on inside that might explain how you can provide a restriction without the resulting pressure reduction that would typically cause CO2 breakout.

This particular graphic, drawn from above the faucet with the shank end to the right, shows one busy faucet!
US20120073690A1-20120329-D00014.png


Cheers!
 
Echoloc8 said:
Back to the original post re: line length.

Is it possible to make these work? Do these only produce foam, or can they deliver a good pour?

http://www.amazon.com/Faucet-Chrome-Cornelius-Disconnect-Attached/dp/B003ZZRR3K/ref=sr_1_1?ie=UTF8&qid=1366411028&sr=8-1

If they can work, why? They should effectively amount to zero, or just a few inches of line length.

-Rich

This work fine at really low pressure. The place I have seen them used is at parties where the pressure on the keg is dropped for serving.
 
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