Moving to Kegs, Should I worry about exploding Kegs?

[R.G.]

Hi All
Moving to Kegs.
I started reading and encountered several cases reported about exploding Kegs.
I'm concerned as I'm living in an Apartment building and my keezer will be in the family room.
So should I worry? doe's the safety valves will do their Job? what if it is a Manual Valve and not Static?
Take worse case scenario that the pressure control fails and also the safety valve fail, will it explode or the ball valves will just pop out?
Thanks
Ye I'm paranoid by nature lol

 

[madscientist451]

There have been cases of keg explosions in commercial breweries, but I've never heard of a corny keg explosion. Consumption of alcohol, which can lead to health problems including death, is more dangerous than your kegs.

 

[seilenos]

You'd have to do a lot of things wrong on purpose to get into the realm of a corny keg "explosion" being possible (and I'm not sure it is possible); it's not something you'd stumble into.

You could have a leak due to bad fittings / hoses. This could cause 5 gallons of beer to end up where it isn't supposed to over a long period of time or you lose a bottle of CO2 ... either case that's more along the lines of "mess"/"annoyance" then "explosion".

 

[seatazzz]

+1 to the above. I doubt you could carbonate a corny keg (using the methods available to homebrewers) to a point where it would explode, i.e. stress the metal to the point where it would fail. The internal parts (poppits, pressure relief valve, lid) would fail long before that could conceivably happen, in my opinion. And that WOULD lead to your delicious beer winding up somewhere you don't want it, usually on the floor.

There's a lot of great information on this forum, but the one point I would stress is make sure your kegs are maintained well. Replacing poppits (little springy things in the posts), o-rings (kits can be got for cheap on amazon and many other sites), and keg lube used liberally on the big o-ring under the lid will keep your kegs and beer happy.

 

[IslandLizard]

What they're saying! ^

A corny keg lid contains a PRV, that's supposed to open at around 65psi. I've never tested it. A corny keg itself can endure at least around 150 psi, when new, but who knows what that rating is once it gets dented, especially if it's in a rather critical area?

I regularly pressurize my (very used) cornies to 30-40 psi when force/burst carbing, and never had a PRV open by itself at those pressures or seen or heard about any problems from others. At some events we have over 3000 corny kegs present, very few are new, most are typical users, dents and all. Although still fairly rare, the most common problem is some beer oozing from a leaky post or poppet, and once in a while leaving a larger puddle or a stain on the floor.

 

[RevA]

my kegs say that they fail at 130PSI or 9Bar pressure. Getting there is possible but only if you do so on purpose, accidentally getting the pressure that high is going to take a mayor series of unfortunate events.

 

[day_trippr]

It'd also require a keg PRV failure, as they should open around 65 psi or lower, as was mentioned...

Cheers!

 

[R.G.]

Thanks a lot all
That is reassuring.
BTW
What is the pressure most CO2 tanks are kept? because I guess and it is very logical that it can't cause to higher pressure in the keg than its own pressure.

 

[day_trippr]

Whoa - you're way off. If that was true, there'd be no need for regulators
Here's a graph of CO2 pressure for various levels of cylinder fills. Notice even under civilized conditions a cylinder at 100% fill the vapor pressure can easily be over 1000 psi...

Cheers!

 

[R.G.]

Thanks a lot
We use regulators in order to control the PSI level we want, no?
Logically it sounds to me that a vessel with X PSI can't create higher PSI to another Vessel because at X PSI there is equilibrium from pressure POV, but I guess I'm wrong lol
What exactly "% of Rated Fill" means?
Thanks

 

[Gruel]

CO2 cylinders hold a two-phase mixture at 'normal' temperatures. Pressure is constant and independent of fill at a given temperature; it's the boiling pressure of CO2 at that temperature. So pressure does not tell you how full or empty your CO2 cylinder is, weight does. "Rated Fill' is the nominal capacity of your cylinder, for example 5 pounds of CO2 for a 5 lbs cylinder. day_trippr's plot above tells you that should you overfill a cylinder you end up in that part of the world where the pressure rises very suddenly as a function of temperature. You don't want to be there.

Take the 60F line: if you are at 100% fill (5 lbs in a 5 lbs cylinder), and you raise the temperature, the pressure goes up proportionately. Just above 80F you cross the boundary from liquid + gas to all gas, but nothing crazy happens. At 70F you are at 850 psi, at 80F at 980psi (give or take), at 90F the increase in pressure gets a bit larger, to 1150psi or so, but still in line with the temperature change.
But fill the cylinder to 120% (6 lbs for a 5lbs cylinder), and you see that the pressure shoots up like crazy when you increase the temperature just a bit beyond 60F. At 70F you are already at 1100 psi, at 80F you are at 1500 psi, and the pressure versus temperature relationship gets even steeper from there.

When you fill a CO2 cylinder (which YOU are not supposed to be doing, your supplier is) you are transferring a two phase mixture, and nothing except using a scale and paying attention is preventing you from overfilling that cylinder with liquid.

The cylinder has a burst disk or other safety device, but you really don't want that to go off in your home (or car). Too much CO2 in the air will make you feel very uncomfortable before it is is going to kill you, but it would still be super loud and super unpleasant. So don't try to fill small cylinders from big cylinders yourself, unless you really know what you are doing.

 

[R.G.]

Thanks a lot for the detailed explanation
So as long as I have CO2 Cylinders from a supplier actually it shouldn't happened right (unless they don't know what they are doing of course)?
What about the Beer Keg when I'm force Carbonate it? can I reach such situation (let's say worse case scenario that my regulator fail and the PSI increase to Maximum possible from the CO2 Cylinder in to the Keg)?
Thanks

 

[Beer666]

Worst thing happened to me was a keg developed a hole in the bottom which emptied the keg all over the floor and emptied the gas. I searched but could find no reference of this happening to anyone else.

 

[Gruel]

Unless you get extra smart with your plumbing, what Beer666 described is the second worst thing that could happen. (The worst thing being the beer getting sprayed towards the ceiling, not the the floor.)

A good amount of respect towards gas cylinders is never wrong, but if you are feeling really anxious about CO2 cylinders, check whether a local community college offers compressed gas (and/or cryogenic liquid) safety classes. The training videos are totally worth it!

 

[passedpawn]

Worst thing happened to me was a keg developed a hole in the bottom which emptied the keg all over the floor and emptied the gas. I searched but could find no reference of this happening to anyone else.

I had this. Caused by leaving bleach in keg, which ate a hole through bottom. Rubber base under keg kinda slowed the leak. Found 5g of beer in keezer next day. Bye bye keg.

 

[Gruel]

300 type austenitic steels are not super resistant to chlorinated water. Especially not warm chlorinated water. I think you need whatever Rolex is using (904L) if you want to keep submerging your stuff in any kind of chloric or chlorous acid. It's easiest though to just stop doing that, and switch to oxygen based sanitizers. It also smells better.

 

[Beer666]

I had this. Caused by leaving bleach in keg, which ate a hole through bottom. Rubber base under keg kinda slowed the leak. Found 5g of beer in keezer next day. Bye bye keg.

Yeah its gutting. I don't suppose they can be welded.

 

[passedpawn]

Yeah its gutting. I don't suppose they can be welded.

Maybe somebody else would do it. I recycled mine. I can buy another. They are cheap to me.

 

[jseyfert3]

Thanks a lot for the detailed explanation
So as long as I have CO2 Cylinders from a supplier actually it shouldn't happened right (unless they don't know what they are doing of course)?
What about the Beer Keg when I'm force Carbonate it? can I reach such situation (let's say worse case scenario that my regulator fail and the PSI increase to Maximum possible from the CO2 Cylinder in to the Keg)?
Thanks

I bought a used Airgas regulator off eBay a week ago. It worked fine when I hooked it up, then I woke up at 2 am to a loud hissing noise. I went downstairs and the low pressure gauge was pegged at 30+ psi (to high to read actual pressure) and the keg pressure relief valve (PRV) was venting. I shut the tank off and bled off the excess pressure using the pull ring on the PRV.

To recap:

1. My regulator failed, flowing CO2 into the keg without stopping.
2. The keg pressure relief valve kept the keg from exploding.

So no, I would not worry about your kegs exploding. That is why the kegs have pressure relief valves. (at least cornie kegs, I don't think the commercial Sanke regulators have pressure relief valves)

 

[R.G.]

I bought a used Airgas regulator off eBay a week ago. It worked fine when I hooked it up, then I woke up at 2 am to a loud hissing noise. I went downstairs and the low pressure gauge was pegged at 30+ psi (to high to read actual pressure) and the keg pressure relief valve (PRV) was venting. I shut the tank off and bled off the excess pressure using the pull ring on the PRV.

To recap:

1. My regulator failed, flowing CO2 into the keg without stopping.
2. The keg pressure relief valve kept the keg from exploding.

So no, I would not worry about your kegs exploding. That is why the kegs have pressure relief valves. (at least cornie kegs, I don't think the commercial Sanke regulators have pressure relief valves)

Thanks a lot, that is reassuring.

 

[verboten]

no