Collapsed Mash Tun

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I just joined this service. I brewed my first batch of beer in 1997. I love brewing. I had a very strange thing happen this weekend. Whilst transferring from the mash tun in a three kettle system to the boil kettle, the mash kettle collapsed. Anyone else experience this? I took it as a sign from the mash gods to pay for a membership.

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No way! Hope she wasnt full? My mash tun cant collapse its made of metal metal:). Hope you wernt burnt or anything in the process and that you could atleast ferment some wort welcome too the forums;).
 
I just joined this service. I brewed my first batch of beer in 1997. I love brewing. I had a very strange thing happen this weekend. Whilst transferring from the mash tun in a three kettle system to the boil kettle, the mash kettle collapsed. Anyone else experience this? I took it as a sign from the mash gods to pay for a membership.

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That's a pretty small mash tun! Is it aluminum? And did you sit it on something that didn't support the entire bottom? I'm trying to figure out how that could happen and am coming up blank. Normally a pot will handle the full weight of the water and strange to me, unless it's an illusion, is the bottom appears to be bent upward. If it were due to the weight of the wort, the bottom would be bowed outward. Because of the way pressure - the weight of the wort - works, vessels burst but don't normally collapse.
 
No way! Hope she wasnt full? My mash tun cant collapse its made of metal metal:). Hope you wernt burnt or anything in the process and that you could atleast ferment some wort welcome too the forums;).
OK. The tun is aluminum, 6010. We've used the pot for eight months. She was completely full. I don't know what 'metal metal' is. No one was injured. Got good wort for two more batches after the (disastrous, majical, mystical) collapse.

Thank you
For the welcome.
 
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That's a pretty small mash tun! Is it aluminum? And did you sit it on something that didn't support the entire bottom? I'm trying to figure out how that could happen and am coming up blank. Normally a pot will handle the full weight of the water and strange to me, unless it's an illusion, is the bottom appears to be bent upward. If it were due to the weight of the wort, the bottom would be bowed outward. Because of the way pressure - the weight of the wort - works, vessels burst but don't normally collapse.
The tun is 32 qt aluminum. It was sitting on a 14 inch square, 1/8 inch expanded mild steel. Please rest assured, this is no illusion. The bottom is collapsed upward, right up to the sparge screen. That is about one and a half inches.

Best regards.
 
I have a theory... Of course I have the benefit of being there.

Before flame out on the mash, I started the pump to the boil kettle, full blast. When the flame out occurred, small particles of the grist settled on the screen and plugged it off. The momentum of the wort through hoses created a fluid displacement vacuum, and collapsed the tun.

That's plausible!


 
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That is strange... Hard to imagine the pump could have that much pull but yes, possible. Welcome to the forum!
 
Aluminum pot, stuck sparge, pump on = collapsed tun. The vacuum created by the liquid under the false bottom leaving the space quickly sucked it right up.
There's an mathematical equation somewhere for exactly what happened, but I never took physics or calculus. :rolleyes:
 
Oh metal metal is stainless steel its one of my many typos sorry:rolleyes:.
 
Possible. Also if you had air in there and things were sealed and it was cooled, that could collapse it as well. Didn't occur to me that the system might be closed. The bottom is likely the weakest point - I think you might have figured it out!
 
Before flame out on the mash,
I'm not used to the term "flame out" being applied to the mash process. I assume that you mean that you direct fire for mash out temp and you started pumping before that was reached? Whatever the case, the fact that the pump was pulling more liquid volume than the false bottom would allow into the space below it created a vacuum and collapsed the bottom.
I'm wondering why you'd start pulling wort out that quickly. It doesn't look big enough for a full-volume recirc tun. Based on the pic and info given I can't visualize your system or process.
Since it's time for a new pot, get at least a 30 quart stainless ( you can find one for $50 or less) and install a weldless ball valve.
 
I agree with the pump theory. I once had a stuck mash, and I mean really stuck mash(as in abandon the brew day) and the vacuum created bent my false bottom and produced all kinds of popping noises from the pot. I am not sure I understand all of the factors at play but your theory seems to work. The only part I can not reconcile is this: even with the pump on full throttle, a good mash bed would let enough liquid through to avoid the crushing vacuum; any chance you had a stuck mash at the same time? Or, the lid was on the pot at the time of the implosion?
 
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I agree with the pump theory. I once had a stuck mash, and I mean really stuck mash(as in abandon the brew day) and the vacuum created bent my false bottom and produced all kinds of popping noises from the pot. I am not sure I understand all of the factors at play but your theory seems to work. The only part I can not reconcile is this: even with the pump on full throttle, a good mash bed would let enough liquid through to avoid the crushing vacuum; any chance you had a stuck mash at the same time? Or, the lid was on the pot at the time of the implosion?
Well, nflamed, the mash bed is the diameter of the tun, 14 inches. The lid was not on. Maybe it was a stuck mash.
 
I'm not used to the term "flame out" being applied to the mash process. I assume that you mean that you direct fire for mash out temp and you started pumping before that was reached? Whatever the case, the fact that the pump was pulling more liquid volume than the false bottom would allow into the space below it created a vacuum and collapsed the bottom.
I'm wondering why you'd start pulling wort out that quickly. It doesn't look big enough for a full-volume recirc tun. Based on the pic and info given I can't visualize your system or process.
Since it's time for a new pot, get at least a 30 quart stainless ( you can find one for $50 or less) and install a weldless ball valve.
You're correct JA. The kettle was 32 quart. The pump is a mag drive.
 
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