Author Topic: Spare air  (Read 430 times)

Offline JD

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Spare air
« on: June 19, 2017, 08:53:55 PM »
I have a large propane cylinder which has stood outside open to the elements for a few years. I want to add this tank to my air system for extra storage. I have all the fittings I need to use the original top valve. I can also get the cylinder hydraulic tested.
What is the best way to clean out the inside of the tank to make it gas free.
John
If you cant fix it hit it with a bigger hammer

Offline Pete49

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Re: Spare air
« Reply #1 on: June 19, 2017, 10:45:22 PM »
Remove the top valve, add some water and swish it around empty. Rinse and repeat until satisfied,dry out and then replace top valve and go for it.
Pete
oops..........oh no.........blast now I need to redo it

Offline Pete.

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Re: Spare air
« Reply #2 on: June 20, 2017, 12:33:24 AM »
I wouldn't even bother with drying it out, it'll get water in it as soon as you start pumping it full of air.

To that end I would mount it on the wall upside down and fit a drain loop on the inlet.

Offline David Jupp

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Re: Spare air
« Reply #3 on: June 20, 2017, 02:38:18 AM »
Getting cylinder hydro-tested would also empty, rinse, and dry it...

Offline JD

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Re: Spare air
« Reply #4 on: June 20, 2017, 04:15:44 AM »
Gentlemen thanks for the quick reply.
Pete, drain loop that should help keep moisture down.
David,Pete49 water seems to be the way to go thanks.
John
If you cant fix it hit it with a bigger hammer

Offline mattinker

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Re: Spare air
« Reply #5 on: June 20, 2017, 05:02:06 AM »
If you want to hydro test it yourself, fill it up with water, make up an adapter to fit a high pressure bicycle and pump it up to 1 1/2 times your desired working load. As it's filled with water, which is not compress-able, if it bursts, the compressed volume is so small that it won't be dangerous!

Regards, Matthew

Offline Pete.

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Re: Spare air
« Reply #6 on: June 20, 2017, 05:33:18 AM »
Or fill it with water to the very brim and warm it up.
Pressure should rise quickly.

Offline mattinker

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Re: Spare air
« Reply #7 on: June 20, 2017, 06:11:22 AM »
Or fill it with water to the very brim and warm it up.
Pressure should rise quickly.

High pressure bicycle pumps are cheap and come with a pressure gauge!

Online Pete W.

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Re: Spare air
« Reply #8 on: June 20, 2017, 08:55:07 AM »
On my propane bottle the delivery coupling has a left-hand thread which I thought was standard practice for containers of fuel gases.

I wouldn't know about the thread into the body of the tank, i.e. the one upstream of the closure valve. 
Best regards,

Pete W.

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Offline vtsteam

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Re: Spare air
« Reply #9 on: June 20, 2017, 09:50:15 AM »
I found a tar like substance on the inside of a 20 lb propane tank I used for a furnace casing. It was not soluble in water or detergent after many cleanings. This substance had released small amounts of propane odor for several years after the valve had been left open, and before the tank was cut. I don't know how you feel about that, but just thought I'd mention it.

(Also, FYI my tank was cut open with a grinder -- not a torch -- while filled with water and the valve removed.  I realize this is not about cutting a furnace casing, but using an intact propane tank as an air receptacle, but thought I should include this detail, in case someone tries cutting one for a furnace on reading that I had done it. Very important when cutting a tank that it be filled with water, and a large opening for the remaining small volume is available.

Many people on other fora have confused rinsing a tank with water before cutting, with filling with water while cutting. Totally different situations. And if cutting an unfilled tank with a torch with an organic tar inside, is a recipe for vaporization of the organic, and explosion.)


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Steve
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Offline mcostello

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Re: Spare air
« Reply #10 on: June 20, 2017, 12:08:05 PM »
Propane and other gases leave a residue in transmission pipe lines that needs cleaned out now and then, You just got "something" extra. Be glad They don't figure out a way to charge You for it. :bugeye:
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