McMaster Keg O-Ring List

SSBrew - 728
Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum

Help Support Homebrew Talk - Beer, Wine, Mead, & Cider Brewing Discussion Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Last edited by a moderator:
How would the 4061T118 compare to the 9396K18.

They are square, but Buna-N.

These are probably too thick. I didn't realize what these o-rings were for until I received them!


Does anyone know if it is possible to replace the small rings on the popets or vents?
 
I can confirm from this weekend that the cornie post o-rings will ALSO work on a paintball tank. Had one shredded, tank was leaking at "the adapter" and I threw one (from amazon above) on there and all is right-as-rain now.
 
Floydsview said:
Has anyone used the above silicone orings for pin-lock's?
Click to expand...

Silicone is not a good choice for Corny post Orings, and if used elsewhere in your kegging setup, will just complicate your life with lubricant incompatibilities.

Why silicone is not a good choice for keg posts:
Silicone is only recommended for static placement- like a keg lid or dip tube. It does not hold up well when subjected to dynamic stresses- like removing & replacing keg QDs.

Lubricant incompatibility:
Silicone rubber is not compatible with silicone based lubricants (i.e. "Keg Lube"). A silicone based lube will soften, enlarge, and degrade a silicone rubber Oring making it even more susceptible to dynamic stress damage. This will result in randomly occurring leaks (which I think are more sinister than a leak at initial assembly time).

Silicone is, however, compatible with petrolatum based lubes (Petrol-Gel, Lubri-film, etc.), and they are the most readily available lubes for use with silicone. Buna-n, conveniently, is compatible with both silicone and petrolatum based lubes.

Why you should still care about lubricant incompatibility:
Sankey keg valves (EPDM) and shank/coupler gaskets (Neoprene) are incompatible (highly for EPDM in my experience) with virtually all lubricants made for silicone rubber as most are petroleum based. There are some dual use lubes, but they are prohibitively expensive, hard to source, and have dubious food safiness (any Colbert fans out there?).

So, if you will never encounter EPDM (Sankey), Neoprene (shank/coupler gaskets), or for that matter almost any material besides silicone rubber and Buna-n, you could get away with switching to a single petrolatum based lubricant.

Why there are still no good arguments for using silicone rubber for kegs:
If you have a post that will only seal with a silicone Oring, it would be better to find out why, and fix it. Using a silicone Oring to remedy the situation will likely just cause a random sealing issue after it inevitably fails due to wear.

For dip tubes, given the better sealing properties of the "X-rings" (quad/dual/double seal), and that they have only been found (so far) in Buna-n, there really isn't much of an argument for silicone here either.

For lids, same goes as for posts- find the problem: bent lid, worn feet, bent keg flange,etc., and fix it. (More than likely fixing the issue will make your lids and kegs interchangeable so you don't have a panic situation when you forget which lid goes where with what Oring.) There isn't the danger of dynamic damage with lids, except during handling, but the lubricant issue remains.

Applications where silicone rubber does make sense:
For 'weldless' kettle fittings they are a good choice because of their high heat ratings. It is a static placement, and lube shouldn't be used in this application anyway, so it doesn't cause any lubricant compatibility issues. Although for stainless vessels, getting the fittings welded or soldered is a much better solution- regardless of what Blichmann fanboys have been brainwashed into believing.

Same goes for cam and groove (camlock) fittings. Silicone is a good choice since the fitting may be exposed to high heat; it is (mostly) a static placement; and no lube should be used here either.
 
Orings to connect a Sanke keg to a 2" triclamp ferrule (for bottom drain or fermenters) are apparently dash #138, McMaster-Carr 9396K147 in silicone.
 
Does anyone know the McMaster-Carr part number for the rubber airlock gaskets?
 
As far as using silicone o-rings on posts, I use them exclusively, got them for a steal, and I use pure mineral oil for lubricants. Haven't had to replace them in a few months so far.
 
tre9er said:
As far as using silicone o-rings on posts, I use them exclusively, got them for a steal, and I use pure mineral oil for lubricants. Haven't had to replace them in a few months so far.
Click to expand...
Your anecdote of successfully using silicone O rings for QD posts doesn't change the fact that they are not the appropriate choice for this 'dynamic' application. As for using only 'pure mineral oil' based lubes, I didn't state they weren't appropriate, especially for silicone. I also hope you realize 'pure mineral oil' is no different (possibly worse for EPDM and Neoprene) than the lubes I previously mentioned- Petrol-Gel, Lubri-Film, petrolatum, etc. They are all petroleum based products, including your 'pure mineral oil'. It's what puts the mineral in 'mineral oil'.

The point I was making, and still am, are the complications that arise from 'having' to use petroleum/mineral oil based lubes in some places, if you also encounter seals commonly used with commercial draft systems. These range from EPDM on Sankey keg valves (and therefore also couplers), or the very commonly used Neoprene washers for "Beer Nut" tailpiece fittings used on virtually all shanks in the US, even when only using Corny kegs. If the complication arises unnecessarily due to using silicone rubber in an inappropriate location, some would prefer to simplify their lives, especially if it works better as well.

Even if silicone post O rings were free, for some people the additional hassle of multiple lubricants, not to mention the decreased utility/performance versus Buna-N, would make it worth the price of buying Buna-N O rings. Since Buna-N O rings are both cheaper and better performing in Corny post applications, choosing to use silicone in this case does not seem like a wise choice, unless you get them for a true 'steal'.

There seems to be some kind of fascination with silicone, elevating its status to some kind of super material. It has its benefits in some applications, just as other materials have benefits over it in other applications. If silicone were a superior choice for Corny posts, the extra minimal cost would not have been a factor for soda makers. Instead, they chose Buna.
 
cwi said:
Your anecdote of successfully using silicone O rings for QD posts doesn't change the fact that they are not the appropriate choice for this 'dynamic' application. As for using only 'pure mineral oil' based lubes, I didn't state they weren't appropriate, especially for silicone. I also hope you realize 'pure mineral oil' is no different (possibly worse for EPDM and Neoprene) than the lubes I previously mentioned- Petrol-Gel, Lubri-Film, petrolatum, etc. They are all petroleum based products, including your 'pure mineral oil'. It's what puts the mineral in 'mineral oil'.

The point I was making, and still am, are the complications that arise from 'having' to use petroleum/mineral oil based lubes in some places, if you also encounter seals commonly used with commercial draft systems. These range from EPDM on Sankey keg valves (and therefore also couplers), or the very commonly used Neoprene washers for "Beer Nut" tailpiece fittings used on virtually all shanks in the US, even when only using Corny kegs. If the complication arises unnecessarily due to using silicone rubber in an inappropriate location, some would prefer to simplify their lives, especially if it works better as well.

Even if silicone post O rings were free, for some people the additional hassle of multiple lubricants, not to mention the decreased utility/performance versus Buna-N, would make it worth the price of buying Buna-N O rings. Since Buna-N O rings are both cheaper and better performing in Corny post applications, choosing to use silicone in this case does not seem like a wise choice, unless you get them for a true 'steal'.

There seems to be some kind of fascination with silicone, elevating its status to some kind of super material. It has its benefits in some applications, just as other materials have benefits over it in other applications. If silicone were a superior choice for Corny posts, the extra minimal cost would not have been a factor for soda makers. Instead, they chose Buna.
Click to expand...

No problem, and not refuting your points, simply giving my (albeit anecdotal) experience with the silicone o-rings I took a flier on. Your info is good, though, and perhaps next time I'll order the buna-n for $2 less per 100.
 
tre9er said:
No problem, and not refuting your points, simply giving my (albeit anecdotal) experience with the silicone o-rings I took a flier on. Your info is good, though, and perhaps next time I'll order the buna-n for $2 less per 100.
Click to expand...
No problem here either. I just have a habit pointing out when something is anecdotal vs. factual, especially if it appears to have been in response to factual info. Anecdotal evidence can be useful, especially when overly strict/complex/costly guidelines are proven, in practice, to be unnecessary. I don't see that being the case here, given that silicone is both more expensive (for most people), less durable, and introduces complexities.

I have not personally tried silicone post O rings, but even my Buna-N ones have taken a beating from R&Ring QDs. I wouldn't want even worse durability. The likely cause is that most posts, being industry cast offs, are in less than perfect shape, and result in less perfect insides on the QDs, especially in the 'guide portion'.

I have seen you post useful info in the past, so I didn't respond with my usual rebuttal for anecdotal evidence- my Uncle Billy's "lightnin' stopper stick" he carries around during storms. They are a simple device made from a sharpened 8' aluminum rod, and have served him well for many years.

The information I gathered and posted was not easy to find, and even more difficult to decipher. This was mainly due to the amount of mis/disinformation on the subject, especially lubricant and seal material compatibility. The use of silicone for being a poor choice for dynamic seals is (almost) universally agreed on.
 
So for those of us with pin locks and are having some gas leak issues (line gets pushed slightly one way or another and gas leaks) we are recommending the number #112 o-rings? An Buna-N is the better product?
 
brettwasbtd said:
So for those of us with pin locks and are having some gas leak issues (line gets pushed slightly one way or another and gas leaks) we are recommending the number #112 o-rings? An Buna-N is the better product?
Click to expand...
If your Orings are beat up, new ones may help, along with lube.
If your lines are pushing things around, maybe try focusing equal effort there as well. Even with new Orings that work at first, you may not be aware of a leak until your newly filled tank is empty.

Are you fairly certain that's where the (only) leak is? As a leak detector, Star-san works OK, but diluted dish soap is usually a bit better. HVAC guys have some kind of super foaming stuff they use. Must have Carapils in it, or something.

I haven't looked at what size Oring is the latest rec for pin locks, so can't comment on that. For material, it's obvious what I would recommend.

Common CO2 line is fairly flexible, and shouldn't pose that much of a risk to pushing the QDs off axis enough to cause a leak. Those pin-lock QDs are tall, though. At least the ones I have are. One solution to the tall QD issue is to use the new SS pin-ball conversion posts for ~$15/pair, or cheaper sometimes. They will increase the value of your kegs by about the same amount, if you ever plan to sell them. Might be a decent solution if you have a mix of kegs.
 
cwi said:
The use of silicone for being a poor choice for dynamic seals is (almost) universally agreed on.
Click to expand...

I wouldn't really consider the post oring of a corny keg to be a dynamic seal. When orings are specified for dynamic seals they usually mean seals that spin 24/7 or slide repeatedly back and forth like in hydraulic cylinders. The occasional 1/2" that an oring slides in a keg post connector doesn't even register compared to most dynamic sealing. The vast majority of time a keg post oring is in a static situation. I won't worry at all about a split second of dynamic movement causing damage to a silicone keg post oring. But if one so chooses to spend time jamming a post connector on and off 24/7 for a few months then silicone is a bad idea.
 
fifelee said:
I wouldn't really consider the post oring of a corny keg to be a dynamic seal. When orings are specified for dynamic seals they usually mean seals that spin 24/7 or slide repeatedly back and forth like in hydraulic cylinders. The occasional 1/2" that an oring slides in a keg post connector doesn't even register compared to most dynamic sealing. The vast majority of time a keg post oring is in a static situation. I won't worry at all about a split second of dynamic movement causing damage to a silicone keg post oring. But if one so chooses to spend time jamming a post connector on and off 24/7 for a few months then silicone is a bad idea.
Click to expand...
Except that in those 'standard dynamic' applications you mention they are usually dealing with machined/polished surfaces, proper alignment, and in a grease bath of some sort. The corny post situation is dealing with crappy molded plastic that frequently has some non-trivial surface defects from being jammed onto 30 year old metal posts. Not to mention getting assaulted by the the locking mechanism, unless you use some king of jig to install your QDs.

Have you looked inside your QDs?
Have you looked at your O rings?
I have, and my post O-rings show significant wear, probably from a variety of things. I wouldn't want even less durability.

I don't see any of the properties of silicone being useful in this situation, and many disadvantages.
Can you offer any advantage for using silicone over Buna?
 
cwi said:
Except that in those 'standard dynamic' applications you mention they are usually dealing with machined/polished surfaces, proper alignment, and in a grease bath of some sort. The corny post situation is dealing with crappy molded plastic that frequently has some non-trivial surface defects from being jammed onto 30 year old metal posts. Not to mention getting assaulted by the the locking mechanism, unless you use some king of jig to install your QDs.

Have you looked inside your QDs?
Have you looked at your O rings?
I have, and my post O-rings show significant wear, probably from a variety of things. I wouldn't want even less durability.

I don't see any of the properties of silicone being useful in this situation, and many disadvantages.
Can you offer any advantage for using silicone over Buna?
Click to expand...

If you have ever dealt with hydraulic cylinders on farm equipment you know they are far from a fine polish surface (damn dirt and rocks). Again even with polish, alignment, and lube there is no comparison between a typical linear dynamic seal that may see 1000 two foot long cycles per day (at 1000 psi) to a keg post that sees 1/4" of travel once a month (at 15 psi).

That said, I agree the advantages of silicone aren't very strong and I to typically use buna. Silicone will form (seal) better around the defects you mention, but to me that isn't usually worth the cost because if defect are that bad I fix the defect. All I'm saying is the split second a silicone keg post oring sees dynamic movement will not cause damage on 99.9% of defects. If there is a defect so bad a 1/4" of travel will damage a silicone oring it will also damage a buna. In that case fix the defect. Your lube incompatibility of silicone is a much stronger argument then dynamic seal issues. Although a slightly swollen oring isn't always bad.

Personally the only real wear I have seen on post orings is on the kegs I got from a scrap yard. I assume those orings had years of caked on soda that caused the damage. New oring I have installed (silicone or buna) hold up just fine. Plus I think most hombrewers like me change the oring every few keg uses. If you want to keep the same oring for 10 years then I agree buna all the way. But for most homebrewers I say if you want silicone don't worry a bit about an occasional 1/4" of dynamic travel and they may even seal a bit better on an imperfect QD surface. Actually, cwi, if your QD's are really beat up, you may want to try silicone orings and just change them often;) or maybe get some new QDs.

Homebrewers if silicone makes you feel better buy silicone. They likely will seal slightly better on defects plus they come in a very attractive orange color. If you see damage change them. If you are worried about cost buy buna. If you see damage change them. If your QDs are so beat up they damage any oring, then get a new QD. Now can we all just relax and have a beer.
 
Fifelee said:
When I make my next McMaster-Carr order, I will try these: Silicone Oring 10mm(ID)x3mm
Floydsview said:
Has anyone used the above silicone orings for pin-lock's?
Click to expand...
Click to expand...

I did finally try the 10mm (ID) x 3mm oring on my pin locks. Yes cwi I used Buna. I had to stretch them a bit more then I like, but they seem to seal very well. When placing the QD you can feel how it is a tighter fit than the #111 or #112 orings. I'll be using them from now on and will report any issues. Might even order some silicone to upset cwi.
 
fifelee said:
If you have ever dealt with hydraulic cylinders on farm equipment you know they are far from a fine polish surface (damn dirt and rocks). Again even with polish, alignment, and lube there is no comparison between a typical linear dynamic seal that may see 1000 two foot long cycles per day (at 1000 psi) to a keg post that sees 1/4" of travel once a month (at 15 psi).
Click to expand...

The hyd cylinders I've seen don't usually use O rings on the exposed surface. They also usually leak like sieves. Maybe they should follow your advice and use silicone wipers and seals? Doubtful. The comparison of QDs to hyd cylinders or rotating seals is not valid.

fifelee said:
That said, I agree the advantages of silicone aren't very strong and I to typically use buna.
Click to expand...
Had you stopped there, I probably would have let all this slide.

fifelee said:
Silicone will form (seal) better around the defects you mention, but to me that isn't usually worth the cost because if defect are that bad I fix the defect.
Click to expand...
If the defect is bad enough to make a Buna O ring leak, it would be bad enough to shred a silicone one. Durability wins out for this type of fitting.

fifelee said:
All I'm saying is the split second a silicone keg post oring sees dynamic movement will not cause damage on 99.9% of defects.
Click to expand...
I don't see how the time factor (split second) is relevant, and faster is actually worse.

fifelee said:
If there is a defect so bad a 1/4" of travel will damage a silicone oring it will also damage a buna.
Click to expand...
If the defect is so small that it will not damage a silicone O ring, a Buna O ring will also seal just as well. See, I can do it, too.

fifelee said:
Your lube incompatibility of silicone is a much stronger argument then dynamic seal issues. Although a slightly swollen oring isn't always bad.
Click to expand...
Except that silicone swollen/degraded from improper lube also has drastically reduced integrity/durometer.

fifelee said:
Personally the only real wear I have seen on post orings is on the kegs I got from a scrap yard. I assume those orings had years of caked on soda that caused the damage. New oring I have installed (silicone or buna) hold up just fine. Plus I think most hombrewers like me change the oring every few keg uses. If you want to keep the same oring for 10 years then I agree buna all the way. But for most homebrewers I say if you want silicone don't worry a bit about an occasional 1/4" of dynamic travel and they may even seal a bit better on an imperfect QD surface.
Click to expand...
You have a talent for hyperbole in making your case. Split seconds, 1/4", 10 years, etc. I just don't see it making the case for silicone. Maybe if you included direction for replacing them 20-30 times as often, taking 1000 times more care when R&Ring QDs, using new QDs every time you switch kegs, etc., then your case for silicone would be a bit stronger.

fifelee said:
Actually, cwi, if your QD's are really beat up, you may want to try silicone orings and just change them often;) or maybe get some new QDs.
Click to expand...
They will just get beat up again from the posts, and from reaching around/over things when trying to install the QDs. Also, it's more than 1/4" of travel, and the O rings do more than just seal, they also provide some support against deflection, so the correct durometer is important there as well.

I found the solution to QDs, poppets, relief valves, and all Corny issues- it's called Sankey.

fifelee said:
Homebrewers if silicone makes you feel better buy silicone. They likely will seal slightly better on defects plus they come in a very attractive orange color. If you see damage change them. If you are worried about cost buy buna. If you see damage change them. If your QDs are so beat up they damage any oring, then get a new QD. Now can we all just relax and have a beer.
Click to expand...
Yes, if silicone makes you feel better, buy it. Just don't go around squawking that it does anything more than impress the ladies.

As for when it's time to change out a silicone O ring, the best indicator is your empty CO2 tank.
 
cwi, when you wrote "Not to mention getting assaulted by the locking mechanism", I couldn't stop laughing as you take minor issues to such an absurd level. I thought it would be fun to mess with you, but I have better things to do then continue this silly discussion. You win. Although I have a mechanical engineering degree and spent eight years specifying orings and oring lubricants you have convinced me a seal that doesn't move 99.9999% of the time is dynamic and a minuscule amount of travel over normal minor defects will shred silicone orings. All homebrewers who use silicone orings should be subject to your public mocking.
 
fifelee said:
I did finally try the 10mm (ID) x 3mm oring on my pin locks. Yes cwi I used Buna. I did have to stretch them a bit more then I like, but they seem to seal very well. When placing the QD you can feel how it is a tighter fit than the #111 or #112 orings. I'll be using them from now on and will report any issues. Might even order some silicone to upset cwi.
Click to expand...

Thanks for the info... just for safe measure, these are the ones you used? http://www.mcmaster.com/#catalog/119/3478/=m6ci0r

It's nice to have a definitive answer on Pin-Lock O-Rings... I have not used my pin lock kegs in 2 years since I dumped 1/2 a keg into the bottom of my fridge!
 
I'd also like to add an O-Ring to the list. Many of us use the Polysulfone Disconnects by CPC.
548768_4701094334779_1507728442_n.jpg


The O-rings are thin and don't generally hold up well, so for those of you who need to replace them here is that O-Ring from McMaster-Carr.
Dash - 016
ID: 5/8"
OD: 3/4"

http://www.mcmaster.com/#o-rings/=m6cnec

Hope this helps.
 
mmurray said:
Thanks for the info... just for safe measure, these are the ones you used? http://www.mcmaster.com/#catalog/119/3478/=m6ci0r

It's nice to have a definitive answer on Pin-Lock O-Rings... I have not used my pin lock kegs in 2 years since I dumped 1/2 a keg into the bottom of my fridge!
Click to expand...

I ordered from Amazon, but the 9262k263 (3mm Wide x 10mm ID) from McMaster in your link above is what I would use.
 
Anyone know a Canadian source (or 'established customer')?
From McMaster-Carr, after I ordered some.:-
"Due to the complexity of U.S. export regulations, McMaster-Carr accepts international orders only from our established customers. This decision also applies to orders shipping within the United States, because it is based on the final destination of the items. We cannot accept this order or future orders."​

I see this was adressed in another thread:-
https://www.homebrewtalk.com/f35/canadian-corney-keg-o-ring-suppliers-108061/
 
SP0tter: Anyone know a Canadian source (or 'established customer')?

From McMaster-Carr, after I ordered some.:-
"Due to the complexity of U.S. export regulations, McMaster-Carr accepts international orders only from our established customers. This decision also applies to orders shipping within the United States, because it is based on the final destination of the items. We cannot accept this order or future orders."​

I received this same reply today, sounds like a crock to me but that is how they roll...

Ordered everything I needed, including the quad rings from:

http://www.oringsandmore.com/

And they take Pay-Pal!
 
Package, from oringsandmore, as described earlier, arrived safely.
I have replaced the post external 'O' rings on all four kegs.
No problems since!
:mug:
 
The dip tube o-rings that came on the kegs I've bought from soda distributors have a square cross-section instead of round.
McMaster# 4061T155

Same for the plastic ball-lock disconnects.
McMaster# 4061T118

I've never had a leak due to o-rings. But I have had poppets leak on kegs that are waiting their turn in my non-kegerator refrigerator - with nothing connected to them.

I drilled an 5/8" hole in the bottom of a film canister (remember when cameras used film?). Place over the keg post so it sits on top of the o-ring, and add a little water - a leaky poppet will be readily apparent.
 
I tried the universal poppet valves. They work OK but not as well as the originals.
 
I just read through all the threads here and I didn't see any mention to replacement o-rings for the pressure relief valve. I've google'd and I see a lot of PRV's advertised as having replaceable o-rings but nobody seems to sell them or even list a size. Does anyone have a size or source for that o-ring? I've attached a picture of the type of PRV that I have, I don't know if there are any different ones.

PRV.jpg
 
Can someone please tell me what o-ring I need to purchase from McMaster to use on poppets for a pin-lock keg?
 
helibrewer said:
Here is a poppet valve solution:
http://www.kegkits.com/Merchant2/merchant.mvc?Screen=CTGY&Category_Code=PVALVE

They are universal valves with replaceable o-rings.
Click to expand...

Been using these a month now.... retrofitted 5 kegs. The poppets seem to fit well. Springs included are quite stiff amd long. They fit but you actually have to press on your posts during installation. The new poppets/springs limit flow significantly compared to the older style..... for example if I hooked up a keg with only some star san in it just looking for am O2 purge, with the old poppets my gas regulator would scream and the keg was filled in a few seconds, utilizing the universal poppets the flow is much more regulated..... same situation now takes 30 seconds and no feedback from regulator. It's also much harder now to press on ball lock fittings to top of the keg.... like crazy hard. Might switch to a metal type fitting instead of plastic.
 
Does anyone have a Amazon link to Buna o-ring for posts? The previous post is for silicone, not sure if anyone knows the Buna counterpart.
 

Similar threads

mashdar
Misc keg o rings material
Replies
10
Views
558
day_trippr
day_trippr
hopsnmalt
For Sale New Cornelius Keg Lid O-Rings For Sale
Replies
1
Views
489
hopsnmalt
hopsnmalt
P
Texas Torpedo Kegs (5 Gallon)
Replies
4
Views
666
jpb2716
J
P
Sold Corny Kegs (Plano, TX)
Replies
3
Views
581
piperbrew
P
RichBenn
Keg gaskets, sealing gaskets and leaks
Replies
28
Views
2K
mac_1103
mac_1103

Latest posts

Back
Top