Bulged torpedo keg

[Michael Bickford]

My poor kegerator froze the other week.

Unfortunately one of my torpedo kegs popped the domed bottom out.

Has anyone ever fixed this problem?

Would it be possible to heat, seal and cool the keg, and maybe get it to pop back up? I.e. crushing a can w/ a vacuum.
Seems worth a shot. If i ruin the keg, i wouldn't be terribly upset.

 

[IslandLizard]

I seriously doubt that's fixable, and definitely not with gas pressure.
The pressure/force during a freeze up can be several hundreds of pounds (or more) per square inch. 65 psi from a CO2 tank won't even put a dent in it, so to speak.

 

[Broken Crow]

Do NOT take a torch to it! I forget the temperature, but SS ceases to be stainless under high heat for more than so many seconds and will need to be re-passivated properly..not just the DIY citric-acid treatment that is adequate for small-scale issues. Can you post a picture? Does the keg no longer sit straight? Is adding adhesive feet to the outer ring to lift the 'dome' off the floor an option?... if you can do that, you can probably continue to use it as long as there is no significant damage elsewhere.

EDIT: BTW: Welcome to HBT!

 

[day_trippr]

A picture might be helpful, but my inclination would be to use a plastic mallet to bang the convex back into concave...

Cheers!

 

[IslandLizard]

A picture might be helpful

Yes, a picture please! It's hard to imagine what it looks like and if and how it can be fixed, and in an elegant way.

A picture might be helpful, but my inclination would be to use a plastic mallet to bang the convex back into concave...

I doubt that would work.
A hydraulic press using a carefully shaped pre-form, maybe.

I'd let it be.
For no extra effort you'll get a good half pint of extra volume out of that keg. That's almost priceless!

 

[Broken Crow]

A picture might be helpful, but my inclination would be to use a plastic mallet to bang the convex back into concave...

Cheers!

A small dent in SS can usually be banged out, but convex>concave will lead to much deeper fractures that are likely to start a corrosion cycle... may or may not happen, but I'd predict a ring of rust inside a year. Only the surface or SS products is effected by passivation, a crack allows an O2 pathway in steel the same way we can see it form in old silicone.

 

[Michael Bickford]

 

[day_trippr]

Impressive.

 

[IslandLizard]

Speechless.

 

[Broken Crow]

How DIY do you feel? You could make an outer-ring for it and epoxy it to the bottom. Would the added height be a problem in your kegerator? The extra half-pint sounds appealing.

 

[IslandLizard]

How DIY do you feel? You could make an outer-ring for it and epoxy it to the bottom. Would the added height be a problem in your kegerator?

Excellent suggestion!

Any material could work. Such as a rim of foam (cut from a rubber floor tile) or wood. Or a ring of something that's already pre-made, like a piece of PVC sewer pipe or coupler.
I'm guessing you'd need to add about 3/4" to clear the dome?

The extra half-pint sounds appealing.

He may need to lengthen the dip tube a tad to get the extra beer out of the new bottom. Use a short piece of tight fitting vinyl tubing, it's adjustable.

 

[Broken Crow]

Excellent suggestion!

Any material could work. Such as a rim of foam (cut from a rubber floor tile) or wood. Or a ring of something that's already pre-made, like a piece of PVC sewer pipe or coupler.
I'm guessing you'd need to add about 3/4" to clear the dome?


He may need to lengthen the dip tube a tad to get the extra beer out of the new bottom. Use a short piece of tight fitting vinyl tubing, it's adjustable.

Maybe an excuse for a floating diptube?

 

[day_trippr]

I wanna beat that thing back in shape so much my hands are tingling!

 

[Broken Crow]

I wanna beat that thing back in shape so much my hands are tingling!

Me too!! ...except I learned about 'steel cancer' (rust) and it's causes when I was young and repairing all the crap at my dads shop. I'm just trying to look at the image the way I'd look at a porn-star: Look, but don't touch...or nasty stuff can happen.
Otherwise there is commiting to proper passivation:
https://ntrs.nasa.gov/api/citations/20200002231/downloads/20200002231.pdf...and I hate commitments!

 

[Michael Bickford]

How DIY do you feel? You could make an outer-ring for it and epoxy it to the bottom. Would the added height be a problem in your kegerator? The extra half-pint sounds appealing.

The height is a problem, so a ring is not ideal.

I'm going to partially fill it with boiling water, and quench it in ice. Hopefully it will suck back down.

 

[Drewch]

The height is a problem, so a ring is not ideal.

I'm going to partially fill it with boiling water, and quench it in ice. Hopefully it will suck back down.

Given the overall shape of the keg, I think you're much more likely to collapse the sides of the keg than reinvert the dome.

 

[day_trippr]

^almost certainly correct^

 

[day_trippr]

BEAT IT! BEAT IT!



with one of these...
https://www.amazon.com/Neiko-02846A-Hammer-Orange-Handle/dp/B002GQ967Y
Cheers!

 

[IslandLizard]

The height is a problem, so a ring is not ideal.

Use low profile disconnects, like those from Kegland?

I wanna beat that thing back in shape so much my hands are tingling!

Do you think it's possible doing it that way?

 

[day_trippr]

I have no doubt one could work that convexed section back inside roughly where it belongs.
I don't have first hand experience with that specific keg type but I have almost 20 years using cornies and the metal is thin. It's not going to put up that much of a fight. Might not look all that pretty but at least it would stand up straight-er...

Cheers!

 

[Yesfan]

The height is a problem, so a ring is not ideal.

I'm going to partially fill it with boiling water, and quench it in ice. Hopefully it will suck back down.

How small in height is your kegerator? I would think you wouldn't need that tall of a ring, maybe just tall enough so it sets level.

You can try the boiling water, but I don't think that would be enough force. The bottom looks thicker than the sides, so I'd guess the sides would implode first before the dome is reinverted. If it were me, I'd leave it as is and make it a dedicated fermenter for small batches. It's got character now.

 

[day_trippr]

I would be surprised if the metal thickness differs anywhere on a modern keg. No reason for complicating the supply chain and manufacturing processes with different thickness sheet metal. The design uses geometric shaping (the ribs 'n' stuff) to provide strength where needed...

Cheers!

 

[Yesfan]

I would be surprised if the metal thickness differs anywhere on a modern keg. No reason for complicating the supply chain and manufacturing processes with different thickness sheet metal. The design uses geometric shaping (the ribs 'n' stuff) to provide strength where needed...

Cheers!

Bad choice of words on my part. I'm sure the steel is the same thickness all around. I meant like you said with "strength where needed". The bottom of that keg, especially after it went from innie to outie, looks beefier there than the sides.

 

[AlexKay]

Maybe I'm too conservative, but at this point I wouldn't trust it to be safe for use at pressure. Maybe move it to a new role as a (non-pressurized) fermenter?

 

[mac_1103]

I learned about 'steel cancer' (rust) and it's causes when I was young and repairing all the crap at my dads shop

Is it possible that the existing damage has already set this keg up for an eventual malignancy? Might he need to commit to passivation whether he bangs on it or not?

 

[DuncB]

I'd show it to a car panel beater. Should be right in their wheelhouse. They'll have the toys.

But I'd find out how much that would cost, as it might be cheaper to replace.

I also like the idea of a custom boot and then not overpressurise in the future.

 

[tld6008]

I'd leave it , those 4 corners will never POP back into place.

 

[Broken Crow]

Is it possible that the existing damage has already set this keg up for an eventual malignancy? Might he need to commit to passivation whether he bangs on it or not?

Could be.. those corners do look pretty bad which is why I vote to leave it.