Interesting - silicone o-rings on kegs allow o2

Williams 728
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Yeah, almost anything else that you could make an o-ring out of is going to be better than silicone in terms of oxygen permeability. But cony kegs were designed for soda and oxygen is really not much of an issue for Mountain Dew. Silicone has other properties (such as resiliancy) that are highly desirable in that application. It's pretty easy to replace the lid seal.
 
I've had a slow co2 leak in all 3 of my Kegland kegs that could not be detected with liquid soap and after watching this realized what is happening. I contacted Morebeer since I've purchased 3 of the Kegland kegs over the past year. They said Kegland hasn't contacted them (sent their customer service rep the video link) so the o-rings they sold me are fine. Also said they can't get the new low O2 rings. I also contacted Kegland and their reply was:

Hi Dale
The Low2 amnesty is offered by KegLand in Australia for local customers only - we don't handle international distribution at all from this office.

There's nothing wrong with the older silicon o-rings per se - it's just that the Low2 o-rings are (in our opinion) a better product for cases where O2 impermeability is an advantage. As a company, we are always looking for ways to design new products or improve existing ones, and this is just an example of that.

We have actually been including the Low2 o-rings as standard on new 19 and 9.5L kegs for quite some time as a matter of course.

Regards,
Darin

Darin obviously didnt watch their YouTube above, quite alarming for any homebrewer who cares about preserving their beer for more than a few days. Hopefully theulir new low o2 o-rings will be available here soon, but in the meantime does anyone know where we can get something similar in the US?
 
I don't know of a US source for the yellow Kegland o-rings, but you can get non-silicone o-rings that are much less O2-permeable from any number of places including Amazon. But the silicone o-rings shouldn't be leaking per se, especially since it sounds like your kegs are fairly new. I just ordered some oversized o-rings from William's Brewing to try to get a couple of old kegs to seal more reliably.
 
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I don't know what all the fuss about silicone (in homebrewing) is about. In 2013-or 14 we had a korny club buy and they were used rootbeer kegs so all the rubber needed to be replaced. We also did a club buy from WW Grainger and got silicone for the lid and posts. No oxidized beer here,even my black friday beers (some 2 years old ). Most are consumed in 4-6 months, so I don't need unlimited shelf life.
As for the lid leaking ,my SOP is to put keg lube on the lid and post seals every time and since I've adopted that practice I've had no suprise empty CO2 bottles.
 
It seems highly likely that the test method used in the video exaggerates the effect by quite a bit. After all, the amounts of oxygen they're detecting would destroy beer in a matter of days. But the way I look at it is if I'm replacing all the seals anyway then why not avoid silicone? My general approach to oxygen exposure is the same one we used to use for radiation exposure - ALARA (as low as reasonably achievable) - with the notable difference that what's reasonable for one brewer may strike someone else as entirely unreasonable.
 
I haven't watched the video so I don't know what they did, but when legit companies test gas permeability of materials it is common practice to use a pure gas environment on the aggressor side. So, for instance, when you look at test data for O2 permeability of plastic tubing it's highly likely pure O2 was used, which would greatly amplify our typical application...

Cheers!
 
day_trippr said:
when you look at test data for O2 permeability of plastic tubing it's highly likely pure O2 was used
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Exactly. The question is whether just dividing by five approximates the real world application. I suspect that it does not. Which is not to say that this completely invalidates the results.
 
mac_1103 said:
It seems highly likely that the test method used in the video exaggerates the effect by quite a bit. After all, the amounts of oxygen they're detecting would destroy beer in a matter of days. But the way I look at it is if I'm replacing all the seals anyway then why not avoid silicone? My general approach to oxygen exposure is the same one we used to use for radiation exposure - ALARA (as low as reasonably achievable) - with the notable difference that what's reasonable for one brewer may strike someone else as entirely unreasonable.
Click to expand...

day_trippr said:
I haven't watched the video so I don't know what they did, but when legit companies test gas permeability of materials it is common practice to use a pure gas environment on the aggressor side. So, for instance, when you look at test data for O2 permeability of plastic tubing it's highly likely pure O2 was used, which would greatly amplify our typical application...

Cheers!
Click to expand...
From watching the video, it appears they tested atmospheric pressure O2 (~21% of air), and calculated the effect that the measured O2 flow rate would have on a keg of beer. This is a professional testing lab that knows what they are doing. I was impressed by the guy representing the testing lab.

Brew on :mug:
 
mac_1103 said:
Exactly. The question is whether just dividing by five approximates the real world application. I suspect that it does not. Which is not to say that this completely invalidates the results.
Click to expand...
See my previous response.

Brew on :mug:
 
Guess I'll have to watch it again. The pdf with the results says "Results are reported on a 100% oxygen basis, which is the convention for published OTR data. Transmission in normal air (21% oxygen) would be 21% of the above results."
 
Was the o-ring test on 100% silicone o-rings?

Most that I see on Amazon have "Durable rubber, silicone and hard plastic" in the description, are these better?
 
Muddbug said:
Was the o-ring test on 100% silicone o-rings?

Most that I see on Amazon have "Durable rubber, silicone and hard plastic" in the description, are these better?
Click to expand...
I wouldn't order any "O" rings with a description like that. It sounds like they don't know what they are actually made of, or that they will ship whatever they have regardless of what they're made of. The last thing I want is a hard plastic "O" ring. Only order if the exact material is specified.

Brew on :mug:
 
Interesting video. A quick amazon search pulls up a “ keg rebuild kit” with yellow low oxygen seal. Everything else on page 1 was typical silicone.
- looks like morebeer has them
 
i didn't care to look any further than "silicone" in the Amazon title. I was just looking to see if a low-O was being sold. Also the video didn't give a comparison with other types of seals. I'll have to look into that further because i'm not sure what i have or if some other would be better.
 
Bassman2003 said:
I would be suspect of anything from Amazon. They are not expensive from McMaster Carr and you can trust it.
Click to expand...

Thanks, i'll check Mcmaster out. I fixed some sealing issues in the past and assumed if nothing is getting out, nothing is getting in. I have black 0-rings but no idea if they are low permeability. It might be worth a few bucks to know for sure.
 
There are some black o-rings on Amazon that use "silicone" in the description. That doesn't necessarily mean that they really are silicone but it does mean that you have to be careful about trusting Amazon. There are also sets on Amazon that include Buna-N lid and poppet o-rings, but silicone post o-rings. I guess some people really like the pretty colors.
 
fwiw, my intuition is that the big lid o-ring matters more than the numerous small-to-tiny others. I've swapped out the white big ones on the kegs that came with them, and laid in spare EDPM rings for gradual replacement of the others as they wear/break.

I suppose the most obsessive anti-oxygen folks would go further.
mac_1103 said:
You can't assume that black means it's not silicone.
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If @mac_1103 is right, then all the tiny black o-rings inside my CMB ball lock disconnects and ball lock posts could be sub-optimal. But many have beer or CO2 on both sides, and are tiny so present a very small "attack surface" to the outside world.

Cheers!
 
Acknowledging this is a guess, I'd guess silicones won't be black. A vendor would have to add a healthy amount of additional material to do it, and ad cost to the product. For no real reason other than aesthetics, and o-rings aren't really sold on that. Also would guess at least some Amazon vendors mislabel their products intentionally or accidentally to get more hits during searches.
 
tracer bullet said:
For no real reason other than aesthetics, and o-rings aren't really sold on that.
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Except for the silly rainbow colored ones. :rolleyes:
tracer bullet said:
Also would guess at least some Amazon vendors mislabel their products intentionally or accidentally to get more hits during searches.
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True dat. Which is part of why you can't trust them.
 
This is the kit that I got a while back off Amazon. It was the very first hit when I just did a search (and I don't see silicone anywhere in the title or description). They are sold by Captain O-Ring. How could you not trust Captain O-Ring?!? ;) https://a.co/d/4AXYM65

I do have a couple silicone o-rings that came on some kegs from a friend. They are thicker and more squishy than the "standard" o-rings.
 
mashdar said:
nice shade of purple : )
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It would be handy if color reliably matched material, but that's not the reality. Dang. For all I know, the white o-rings I replaced (to up my anti-oxygen game) were not silicone at all. Fortunately, the cost of "known good" replacements is quite modest.
 
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Think it's safe to assume torpedo factory gasket is not silicone? (Black, couldn't find a spec.)

Re the yellow material, morebeer says "Rather than the usual EPDM or Silicone, Low2 gaskets are made from a unique composition of Synthetic M-Class and Cross-Link Elastomers."
 
mashdar said:
This seems to imply nitrile is ~1/20 (edit to 1/3) the O2 permeability of EPDM.
https://www.applerubber.com/hot-topics-for-engineers/the-permeability-of-rubber-compounds/
edit: I'm sure it matters how it compresses, though.
Click to expand...
I do believe you are correct (also, NBR is nitrile / Buna if anyone wonders). I wonder if SL is silicone? I won't assume it, just wonder.

Related is: O-Ring Permeation Chart | Marco Rubber & Plastics | Custom O-Rings Supplier

It does not show O2 unfortunately, but with the remaining gasses one can see a clear trend and make their own assumptions.
 

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