Glass Carboy Pressure Threshold

[etbandit]

Does anyone know what the pressure threshold of a glass carboy is before it starts to crack/explode?

I am thinking of filtering beer directly from my glass carboy fermenter by applying CO2 via an inlet through the silicon bung, which will force beer out a racking cane which will also be inserted through the silicon bung. The beer will then be directed to a 1 micron filter and housing (like that sold by CraftBrewer) and straight into the keg.

I have seen a thread somewhere here that demonstrates this with a plastic fermenter, and was thinking of applying it to my glass carboy fermenter.

CraftBrewer recommends 10kpa during filtration. What is the likely backpressure during filtration and can a glass carboy withstand this sort of back pressure?

Cheers.

 

[Jye]

From some of the stories Ive read about glass carboys breaking I wouldnt apply any pressure!

Checkout Pumpys filtering setup and give that ago with a siphon first.

 

[pint of lager]

I have read posts about people using pressure to start a siphon off in carbouys. Glass has a very small amount of flex, then it will crack.

There are many threads on brew boards about people breaking glass carbouys. The tears about losing all that beer. The tears about the cracked carbouy. The trips to hospital to be stitched up.

Do the extra step, transfer to a keg and then do the filtering.

 

[SpillsMostOfIt]

If you can't find any threads as PoL suggests, here is the one that does it for me, complete with pictures of some of the outcome:

http://www.thebrewingnetwork.com/phpBB2/vi...&highlight=

 

[Jye]

Thats the thread I was trying to find today, but damned if I could remember where it was

Heres the pic.

 

[domonsura]

well then. All those times I've looked at glass carboys and wondered what happens when it all goes pear shaped..............now I know. ouch...

 

[Kai]

I'm saving that picture so I can use it in all those US threads where people insist that glass must always be used over plastic.

 

[Thirsty Boy]

ebandit,

As Jye says, look a Pumpy's thread. You dont need pressure at all to filter. The Carboy up on a bench and the keg or bottles on the floor is enough. Even with the filter housing in line, I was able to suck start a siphon with a turkey baster and the siphon is more than enough to filter a whole batch.

No glass for me, me likey fingers on hands.

Thirsty

 

[Belgrave Brewer]

Off the question/subject a bit, but I'm a HUGE fan of glass carboys and have had no issues whatsoever with them.

Glass is fragile, can crack with boiled water, can shatter when dropped, and might break under pressure.

That being said, if you know these things and are careful, they are one of the best materials (and affordable) to ferment in. No issues from infection due to scratches in plastic, no issues with long fermentations in plastic and oxygen seeping through the plastic, smoother than stainless steel and relatively easy to clean/sterilize/sanitize.

OK, maybe it is not for everyone or for every purpose, but as a fermentation vessel, I find it difficult to match or even beat.

BB

 

[schooey]

I have two glassies, only problem I've ever had with them is you can only really effectively get a 21 L batch out of them by the time you allow head space for fermentation and losses in the trub. Although it is a must to have dry hands when walking around the garage with a full one <_<

 

[Belgrave Brewer]

I have two glassies, only problem I've ever had with them is you can only really effectively get a 21 L batch out of them by the time you allow head space for fermentation and losses in the trub. Although it is a must to have dry hands when walking around the garage with a full one <_<

They make a handle for the glass carboy that slips over the lip. Very useful to carry them around, even with wet hands.

reVox turned me onto them after he dropped his carboy and it shattered into glass shards and beer all over his carpet. There is a post of that incident including pics of the steam cleaner which he rented.

BB