O-rings compatible with Ethanol

[jim]

I was certain that a silicone O-ring was a superior O-ring material to use for my corny keg aging vessels. However, a google search revealed several O-ring compatablility charts all which show that both natural rubber and Buna-N type O-rings are more compatible with ethanol (Ethyl Alcohol) than silicone.

Silicone is rated as a "Fair" O-ring material for ethanol, usually OK for static seals in the first chart. The second compatibility chart shows it as being good.

[bt1]

Jim,

No fan of either...rubber over time goes sticky like melts in high strengths...try it drop a rubber seal in a small amount give it a week then taste it.

Viton, just started using EPDM..looks ok at this stage..needs time, would be my choices.

bt1

[jim]

I started a test with one of the default rubber O-rings last night in a jar of hearts, I'll update this in a week.

Where do you buy EPDM Orings?

[MacStill]

I've been using an EPDM seal for at least a couple of years and cant see any signs of deterioration.

Also used two different types of silicone seals from www.5stardistilling.com.au and the SGK supplied ones deteriorated in only a few runs.

I can get both EPDM & silicone seals and O rings from my supplier :handgestures-thumbupleft:

[drunkmore]

Mac said

I can get both EPDM & silicone seals and O rings from my supplier

Hey mac do we get a choice of sizes? Are they flat like a washer or are the actually an o ring?
The radius I need is 250 mm If they are flat I could do with about 2 or3 mm thick and about 5 to 20 mm wide
Got any ideas on cost? I'm in Brisvegas Qld.4304 don't forget postage.



Wow this is an old post oops

[SBB]

Nothing wrong with reviving old posts Drunkmore, sometimes it jolts memories or makes people ask more questions regarding old topics.
In this case it has, Been gunna ask Mac for a while, do you have O rings for sight glasses to replace the original 2 inch rings supplied by that other bloke????, Im getting a tad worried about mine and wanna replace them.

[MacStill]

I asked for some samples ages ago, apparently they're in stock and on the way.... but yeh still no show :angry-banghead:

[blond.chap]

Nothing wrong with reviving old posts Drunkmore, sometimes it jolts memories or makes people ask more questions regarding old topics.
In this case it has, Been gunna ask Mac for a while, do you have O rings for sight glasses to replace the original 2 inch rings supplied by that other bloke????, Im getting a tad worried about mine and wanna replace them.

Hey SBB, I find the silicone gaskets (meant for triclamp joins) work just fine for sight glasses, they're easier to re-seat as well. I've been slowly replacing my o-rings with them.

[woodduck]

Hi guys, after some suggestions from a few of you to replace the rubber grommet in my thumper it made me question the seals I have in other parts of my still.so I started surfing the theads and found this one. I have used two "milk" fittings (sorry I don't know the correct terminology so I've posted a photo) to join my columns to my boiler. Has anyone else used them and does anyone know if the seals would be ok.

[MacStill]

Looks like RJT fittings to me, those seals arent too hard to find..... pretty sure I can get silicone, EPDM & maybe PTFE. I'd need you to email me some dimensions though before availability is confirmed ;-)

[northernbrewer]

Furthermore about the charts, you gotta remember that ethanol at room temperature and ethanol at 90+ degrees will react differently with the seals. In my opinion the little extra that epdm costs its probably worth it in the long run.

[woodduck]

Hi fella's
I've got this wash here I don't want to leave much longer so until I get some replacements do you recon I could get away with wrapping the seals in thread tape?

[Sam.]

Hi fella's
I've got this wash here I don't want to leave much longer so until I get some replacements do you recon I could get away with wrapping the seals in thread tape?

That's up to you mate, some would some wouldn't, I would but I'm not as risk adverse as some :D

[woodduck]

Thanks mate I ended up wrapping them seems to have worked.

[InglisHill]

A couple of blokes and myself some time ago made a biodiesel refinery from the ground up, it ended up pumping out around 2.5 million litres a year. We used methanol and KOH to react the oils bought into the plant. Then we used various heat exchangers and stills and 'other questionable processes' to make all this happen. To make a long story short, in the three years I was there, I never saw a Viton seal fail, ever. The esters made would just simply chew any rubber product up into a gelatinous mess that was pretty hard to get off anything.

For me that was a pretty good indicator that Viton is up to the task.

In saying that I have been using EPDM seals in my stills for some years and have never found any deterioration in them.

Just my two cents.