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Glass carboy explosion

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I only use a glass carboy for the *rare* secondary and always do my primary in a bucket. I don't care if I can't see the yeast activity through glass. Fun, but who cares? If something is going to give, I want it to be a singular plastic object, not a thousand dangerous glass shards. That happens when we assume "this will never happen to me".
 
I think another possible problem is that many (im not saying the OP did, but maybe) people put their blow off tube too deep under water. This added head pressure makes it more difficult for a clog to clear, particularly in "small" hose (which I use with no problem all the time btw). Don't believe that 6" of head pressure makes a difference? Raise your tube up during active fermentation and watch how much faster it burps.

OP - condolences for the loss of your beer
 
I've been pretty set on using plastic. I can be clumsy at times, and the thought of carrying 5 gallons of liquid in a glass container seems like a disaster waiting to happen.

But, I've never thought it was a ticking time bomb! Bottle bombs? Yeah...but carboy bomb? That's a first for me...

I'm no expert on glass, but I would guess that once you create a single point of intense strain enough to crack in one spot, the entire vessel would shatter (especially holding that much volume) due to the counter pressure design of glass?
 
Yeah, something similar has happened to me, though the carboy didn't explode as spectacularly as yours. I was using an S airlock where I should have used my regular big-ass blowoff tube - and I guess that freakin bung held in there like nobody's business! The airlock got blocked with blowoff, the pressure built, and the whole damned bottom of the carboy blew clean off leaving the entire top section pretty much intact.

Exploding Carboy Alert!

I now use stainless conicals for most brewing, but for 5g batches I still use carboys, however: I never handle my carboys anymore without work gloves. And, I keep them all in milk crates. And I ferment them in small top-opening display coolers with an STC controller. These are water tight so if the carboy blows, it's contained. This was a serendipitous discovery when I had that explosion :)

Sorry for your beer! Blow-off tubes are your friend!
 
I just shed a tear. my condolences!!! I hate to see that much beer go to waste! but you lost it in spectacular fashion, that's impressive
 
I use the standard home brew airlocks (not the S type) but I connect a 3' blow off tube running into a bucket of sanitized water.
 
It was drilled with a blow off tube that was bubbling 6 hours earlier. I don't get it.
 
i am heeding that suggestion and going with larger blow off tubes for sure.

yeah, just had to squeegee the floor. now i have an empty tap in the bar though. Damn!!

Bar.jpg
 
I think another possible problem is that many (im not saying the OP did, but maybe) people put their blow off tube too deep under water. This added head pressure makes it more difficult for a clog to clear, particularly in "small" hose (which I use with no problem all the time btw). Don't believe that 6" of head pressure makes a difference? Raise your tube up during active fermentation and watch how much faster it burps.

That is an interesting suggestion. One of those things I never thought about until you mentioned it. Personally I'm terrified of the blow off tube sucking the starsan back into the batch. Result of this is that I'll try to use less sanitizer in the bucket than the capacity of the tube.
 
Glad no one was around to get hit with any of the flying glass it looks like it went all over. Also took me a while to see I too was looking at wall setup. Very nice... One other possibility is that the carboy develop some stress fractures that was unnoticeable. I drop enough things that don't break which is why I use only buckets or Speidel for brewing. The only glass I use is the Hydrometer and have gone through a few.
 
We could easily get into the carboy vs. bucket debate, but relative to this mishap, it simply makes me wonder why anyone would put such a large volume of highly-pressurized liquid into such a [relatively] large, thin glass container (cheaper ones being made thinner or with inconsistent thicknesses). It would seem that a container this large under pressure would demand a certain amount of elasticity to be functional and safe. However, elasticity is not a selling feature for glass, much less this glass under these conditions. If putting this much liquid under pressure into large glass vessels were a smart and equitable thing to do, why do only homebrewers do it? It is apparent over and over again that there is a point at which a glass vessel this large is not safe under pressure (not to mention empty and wet). "My Carboy Shattered" is a perpetual topic of discussion here on HBT that perpetually begs the question, "Why?" Is the answer found in the vessel itself or the use of it? Is it a matter of poor-quality construction, a mishandling accident or something else that leads to a potentially dangerous event? Or is the use of a glass carboy simply a game of Russian-roulette with physics.
 
[...] it simply makes me wonder why anyone would put such a large volume of highly-pressurized liquid into such a [relatively] large, thin glass container [...]
That's silly. I don't think anyone is deliberately "highly" pressurizing a glass carboy. In almost every case of failure, there can be some type of user mistake to account for it. Like a lot of things in life, there a risk. You have to assess your own level of competence (and luck) and decide if that risk is one you're willing to take.
 
I've been considering shrink wrapping the glass carboys. Keep a loose tension on the wrap and replace when it wears out. Shrink wrap is cheap, could reinforce the carboy making it stronger and could contain a broken carboy.

I still use mine all the time but only for beers that need long term fermentation and conditioning.
 
We could easily get into the carboy vs. bucket debate, but relative to this mishap, it simply makes me wonder why anyone would put such a large volume of highly-pressurized liquid into such a [relatively] large, thin glass container

That would be a good question. Normally we don't have pressurized volumes of anything in glass carboys, though. Somehow, this glass container pressurized when it shouldn't have.

An easy way to avoid this problem would be to get one of those two-hole carboy caps, put the airlock or blow-off tube through one of the holes and cap the other one with a piece of aluminum foil.
 
That's silly. I don't think anyone is deliberately "highly" pressurizing a glass carboy. In almost every case of failure, there can be some type of user mistake to account for it. Like a lot of things in life, there a risk. You have to assess your own level of competence (and luck) and decide if that risk is one you're willing to take.

I didn't mean to infer anyone was "deliberately 'highly' pressurizing" a carboy". I think the OP's event speaks plainly to the fact that the fermentation process creates an adequate amount of its own pressure.

If your premise that "user mistake" causes "almost every case of failure", are you saying that the object (carboy) is only as safe as the user? And if it is true that any given object is only as safe as its user, then a PET carboy employed under exactly the same conditions --- complete with the "user mistake" of a clogged or undersized blow-off --- is safer because of the user? Hmm...
 
It may have been mentioned, but is that concrete that the carboy was sitting on? Could there have been a weird temperature swing? The clogged airlock seems more plausible, but the concrete got me thinking.

Neat wine wall though.
 
I've been considering shrink wrapping the glass carboys. Keep a loose tension on the wrap and replace when it wears out. Shrink wrap is cheap, could reinforce the carboy making it stronger and could contain a broken carboy.

I still use mine all the time but only for beers that need long term fermentation and conditioning.

That's actually not a bad idea. Get a roll of pallet wrap and run a few turns around it. You will still be able to see through it (kinda), and have something that may hold in the chunks if it breaks.
 
I haven't used my glass carboy that I received in my kit and might be trying to trade it in for a plastic one. Seen too many accidents happen with them and with little ones running around it just isn't worth it. Wonder how much I could sell an unused one for if the LHBS won't take it for a trade.
 
DISCLAIMER: I do not, in any way, discount the posts in this thread or the veracity of the OP's claim.

However, setting aside the obvious issues like glass being heavy and slippery when wet, is this a real problem or much ado about nothing? It seems if there was a high degree of risk with fermenting in standard glass carboys then why have they sold (possibly) millions of them and there isn't more substantiated "explosion" claims out there?

I'm not trying to be cynical or "that guy," I'm just trying to determine if I should all of the sudden be more concerned about the 10 glass carboys I have. If it were a real issue it seems the first thing one would learn when they start posting/reading HBT is that glass may blow up instead of NO, YOUR BEER DIDN'T FERMENT IN 48 HOURS. :D
 
DISCLAIMER: I do not, in any way, discount the posts in this thread or the veracity of the OP's claim.

However, setting aside the obvious issues like glass being heavy and slippery when wet, is this a real problem or much ado about nothing? It seems if there was a high degree of risk with fermenting in standard glass carboys then why have they sold (possibly) millions of them and there isn't more substantiated "explosion" claims out there?

I'm not trying to be cynical or "that guy," I'm just trying to determine if I should all of the sudden be more concerned about the 10 glass carboys I have. If it were a real issue it seems the first thing one would learn when they start posting/reading HBT is that glass may blow up instead of NO, YOUR BEER DIDN'T FERMENT IN 48 HOURS. :D

Carboys were not designed with homebrewing in mind as far as I know.
 
Personally I'm terrified of the blow off tube sucking the starsan back into the batch.

Two things to consider
1) for the fermentor to suck the blow-off liquid backwards would require a significant cooling event to occur without any positive pressure created by the beer/yeast
2) to be clear, the blow-off liquid doesn't have to be sanitizer as it will never travel backward during any real-world event regular water will do (just sanitize the blow-off tube itself)
 
Had a buddy have the same thing happen to a chocolate stout in the coat closet. Lot of replacement outerwear from that one. I wear a 6 inch long scar on my right thigh from a slippery glass carboy 16 years ago. I'll never use a glass carboy again. Stainless fermentation for me thank you.
 
So all of my carboys are older, 'heavy' glass. I think they are all stamped with Made in Mexico, and two of them are easily 15+ years old. I have seem some stories about thinner walled ones, so these explosions - are they the thinner variety or both?

I had an IPA blow the inside of a 3pc airlock off the top, and it proceeded to spray a basketball sized circle of hops on the ceiling. If ever I would have thought a carboy would have exploded, it would have been that day. Krausen pushed some hops in the tube, gummed it good and tight, and then the pressure went off with a bang.

I'd think that an airlock would sacrifice itself before the glass, unless the glass was already compromised in some way.
 
Didn't have the time to read the whole thread, but if you think about surface area, the PSI required to blow apart a glass jar (carboy) is quite low.

With a weakened carboy (IE one with regular use) even only a few PSI would be enough to cause damage like what is experienced here. At one PSI a piece of the carboy 10"x10" has 100lbs of force on it.

A bung probably takes 10lbs (or more) of static force to remove it. That said the 10x10 chunk of glass will have about 200lbs or more pushing on it... Multiply that on the surface of the whole carboy and it adds up quick...

Try it with a plastic carboy, you'll see how much a few PSI will flex the plastic.

Cheers,
Max
 
That's actually not a bad idea. Get a roll of pallet wrap and run a few turns around it. You will still be able to see through it (kinda), and have something that may hold in the chunks if it breaks.

I'm gonna procure a roll today at work.
 
I wouldn't think that plastic wrap would have done a substantial job of maintaining this particular explosion, but who knows.

The lesson here may be to pull out the blowoff tube periodically to make sure it isn't clogged. I'm sure others that have have a volcanic carboy eruption or bucket lid launch would concur.
 

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