stacked storage tanks

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rippa25m

Member
Jun 12, 2015
38
Hopkinsville kentucky
I don't get on here and post but I do read a lot of threads and take notes. This is a pic of my two 500 gallon propane tanks I'm stacking.
 

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Nice set up

i stacked 500 also,

Are the denter pieces gonna be completely open for enhanced flow?
 
I don't get on here and post but I do read a lot of threads and take notes. This is a pic of my two 500 gallon propane tanks I'm stacking.


Got enough room to stand them on end? You will get a lot more temperature stacking and "use-ability" especially if you can run down to a low temperature for radiant or panel rads.
 
I scored two 1000 gallon propane tanks for cheap.

Thinking about cutting them in half and welding plate in order to set them on end in new boiler room.

any thoughts on cutting them in half like this?
 
any thoughts on cutting them in half like this?

It maybe overly cautious, but I'd worry about the thickness that you would need for a flat plate end (bottom). I'm guessing that you'll be in a closed system and the potential power of pressure is something that I would want an engineer type person's opinion on. I'm curious on what (thickness) "they'll" say here. What's the dia. of your tanks?
 
I might be overly cautious too - but I wouldn't do any more cutting/drilling of an LP tank than I absolutely had to. If you're lucky it will have enough tappings already that you can plumb in to. You only really need two on each tank, one at the top & one at the bottom. Temp & stat wells can be replaced by strap on & external temp probe controls. Aside from possible leaky welds (I had a couple pinholes even using a pro welder), they were engineered & built that way for a reason. I think cutting in half & welding a plate on will introduce extra stress in the weld area once the tank is stood up & pressurized. Can't say whether it would lead to a problem though - but could see the weld opening up if not done right.

I stacked mine & wouldn't hesitate to do it again - much easier to do, those things are heavy. And tall. I get great stratification, although no doubt that's easier to attain with vertical tanks. Minimizing your flow rates helps tremendously there.
 
Yep
ive had similar thoughts
initially i thought 1 inch plate and make it wider for stability while standing on end

i will talk with an engineer as you said
ill post the result of that conversation
 
NP, took a picture of my wife with the 30' Santa in North Pole, AK last week. What pressure do you run your system? We've done some flat plate end flanges, but never for large diameter pressure vessels. In general this is a bad practice for a pressure vessel. Imagine welding a piece of flat bar onto the end the cylinder section of your tank and pulling on the end of the flat bar from inside the cylinder. The load on the weld tries to peel the weld from the inside. In theory that's how your loading a flat plate end disc weld.

Much better to shorten the center section and re-weld the dome back on. The flat plate can be made to work safely as long as it's thick enough to minimize deflection in the center. The calculation for the center deflection assuming steel isn't difficult. 20 psi on that area is a huge force.

If your system is unpressurized, ignore all the above.
 
X2 on the plates being a bad idea. Like tennman said cut some of the "belly" out of the tanks and put the ends back on. Then build a stand with legs if you need to stand them up.
 
Thanks for all the help

Im 5 minutes from that Santa:)

On another note, can a person buy the dome ends?
this would allow me to make 4 tanks for vertical installation
 
I don't know about around your area but near me we have a place that refurbishes and makes propane tanks ready to buy. They sell the old decommissioned tanks. Still good enough to hold pressure, just out of date tanks. If you could find something like that you could get as many ends as you wanted. But I'm sure you could find them online too. You'll just have to shop around.
 
Thanks for all the help

Im 5 minutes from that Santa:)

On another note, can a person buy the dome ends?
this would allow me to make 4 tanks for vertical installation
I wouldn't give up yet, just get a opinion/solution from some one that is qualified. Depending of the dia of the circle you need, I would guess, repeat guess that the 1" you were thinking of would be plenty. I would think that this would also require pre-heating the heavy plate prior to welding to the maybe 1/4" wall tank. You might ask over at; http://weldingweb.com/forumdisplay.php?10-Welding-Projects-amp-Pictures
Not sure what would be the best "section" to post your question. There is a wide range of knowledge there and I', sure that some of them have worked on "pressure vessel's".
 
I sure hope you guys are wrong. Take a look at my avatar. 1000 gallon tank cut in half and a plate welded on the bottoms. Last winter was their first in operation. They function beautifully but now you have me worried. I bought them from a guy who repurposes these tanks specifically to be used as storage for these kinds of systems. I assume I am not the only one he has made this type for.
 
30-35 psi may not be that much pressure, my cylinder of 80/20 gas for the MIG welder is over 10k psi when filled. If you made it through last year, and the guy makes these regularly, I wouldn't loose sleep over it. I'm sure that a properly sized expansion tank and a properly working p.r valve might just be a little more important in your situation.
 
I can say from experience that a flat bottom will work. It's just not ideal. If the plate is properly welded with the proper reinforcement on the plate, usually on the inside to prevent bulging out, it will work for mild pressure. I wouldn't trust a very high pressure application with plate vs. dome ends.
 
I checked with my guy and he says the plates are reinforced with channel iron on the bottom . He also tests to 35 psi before the tanks are shipped. I usually run at around 20-22 psi max. Sorry, I forgot to ask how thick the plate was.
 
I think I went pretty far, with my tanks. If I did it again, i'd do flat bottoms.
 

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Nice, well Im feeling better about things
But still plan to research the best way ahead
 
I think I went pretty far, with my tanks. If I did it again, i'd do flat bottoms.
These tanks are non-pressurized, correct?
This type of construction will not be able to hold 5 psi, unless there are some stays inside to keep it "flat"
 
Pressurized for sure
35 psi pop off
the flat plate on the bottom will be reinforced
 
ote="kjahnz, post: 1967571, member: 23979"]I think I went pretty far, with my tanks. If I did it again, i'd do flat bottoms.[/quote]
What made you decide to cutt tank and invert dome
Was it clearance
 
I checked with my guy and he says the plates are reinforced with channel iron on the bottom . He also tests to 35 psi before the tanks are shipped. I usually run at around 20-22 psi max. Sorry, I forgot to ask how thick the plate was.
I am interested in the size and thivkness of the plat used for your tanks.
I got two 1000 gallon tank; i want to cutt them in half and weld them same as yours.
4 tanks for a total of about 2000 gallons of storage.
The will be much easier to handle and move like this. If i stack them the entire unit becomes very combersom to handle.

Thnx Morgan
 
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Below a picture of an ASME rated tank (section VIII) with flat bottoms (Hydronic Specialty Supply)
You can clearly see the stays, and there are many of them.
5016092_orig.jpg
 
These tanks are non-pressurized, correct?
This type of construction will not be able to hold 5 psi, unless there are some stays inside to keep it "flat"


Sorry, but yes they are pressurized, tested to 45 psi. Stays, yes, to keep them from cracking open like eggs.
 

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ote="kjahnz, post: 1967571, member: 23979"]I think I went pretty far, with my tanks. If I did it again, i'd do flat bottoms.
What made you decide to cutt tank and invert dome
Was it clearance[/quote]

Not clearance, just repurposing cost and convenience.

If I did it again, I would cut a circle of the same thickness of the tank wall. Recess that 3 or 4 inches into the tank, weld in place. Then using 3 inch flat stock, weld bracing to wall and plate, every 3 to 4 inches."on edge"

I would gain more volume.