De canting Gas

[101RRS]

With the advent of swap and go it is getting harder to fill my small gas bottles so I thought of decanting from my large lpg bottle.

I can connect both bottles together with the regulator removed but do I have to do anything special to get the gas out of the big tank to the smaller one. Someone has said the the bottle to be filled has to be lower than the one form which the gas is coming.

Any other tricks

thanks

Garry

[CraigE]

The gas level has to be higher than the one being filled or it will not flow as liquid. If you are decanting from a home cylinder if the cylinder is nearly empty it will need to be inverted.
Most towns should still have a fill station. Over here and in SA it is usually Kleenheat Gas. You should have Origin (Boral) or something similar.

[101RRS]

Thanks for the info

Gazzz

[disconut]

Originally posted by garrycol
With the advent of swap and go it is getting harder to fill my small gas bottles so I thought of decanting from my large lpg bottle.

I can connect both bottles together with the regulator removed but do I have to do anything special to get the gas out of the big tank to the smaller one. Someone has said the the bottle to be filled has to be lower than the one form which the gas is coming.

Any other tricks

thanks

Garry

8O 8O 8O 8O 8O 8O 8O 8O 8O

www.bcga.co.uk/preview/pdfs/TIS13.pdf

Don't do it!



Trev.

[one_iota]

It is simple physics:

Pressures equalise.

You may fill the empty smaller volume tank depending on the volume of gas in the big one but you will never empty the big one

When you fill a bottle at the servo there is no regulator.

[DEFENDERZOOK]

<span style="color:blue">there is a regulator and a safety switch on the top of the the big bottles....

and the bottle being filled has a pressure release screw open to allow it to fill......
hence giving it a lower pressure than the bottle it is being filled from......</span>

[101RRS]

If I am filling from a 9kg bottle - surely the smaller bottle cannot be over presurised because the smaller bottle would normally be filled to the same pressure if filled at the garage.

Does the garage fill different sized bottles to different pressures?

Gazz

[Ralph1Malph]

Yes,
I am keen to figure this out at well.
At the moment I rely on the spotty, 'english is a second language', teenager at the local servo to do mine.
It doesn't look hard.
Ralph

[CraigE]

Remember the big tanks used for filling also incorporate a pump, they do not fill just on a line. Father in law was a kleenheat gas manager for lots of years. To fill from one cylinder to another you need the correct hose. As said you will not be able to empty the donor cylinder completely using this method. It can get you out of trouble however. I hav also seenthe set up to decant lpg into a vehicle to get out of trouble.

[DEFENDERZOOK]

Originally posted by garrycol
If I am filling from a 9kg bottle - surely the smaller bottle cannot be over presurised because the smaller bottle would normally be filled to the same pressure if filled at the garage.


Gazz



<span style="color:blue">no....they would both have less pressure than the 9kg had at the start as
the same amount of gas is now in a larger area...(two cylinders) and the one being filled will have been releasing pressure to allow the gas to flow into it.....</span>

[abaddonxi]

If you are talking about filling up bbq tanks at a servo, no pumps, just a whopping big tank of LPG and a hose from one to the other. There are very clear simple instructions written on the outside in large letters. It's been a dozen years since I've had a job that needed me to do it, but there are only about four steps in the process.

https://www.aulro.com/afvb/

Cheers
Simon

[hook]

DON'T DO IT
DON'T DO ITDON'T DO IT
DON'T DO ITDont do it,

when you burn the BBQ it use gas.
when you Decan it use liquid.

So the decanting bottle have a blue top, because these bottles have a pick up tube going to the bottem of the bottle, this is to get the liquid at the bottem, not the gas on top.
so the BBQ bottle, don't have a tube in side it, so it gets gas from the top of the bottle.
so if you decan from one big bottle to a smaller bottle you will get gas from the big bottle, not the liquid you want.
DON'T DO IT
DON'T DO IT
you need to turn the big bottle up side down to get the liquid to the pick up point, so the liquid will go the less presser (small bottle)
DON'T DO IT
DON'T DO IT
DON'T DO IT
DON'T DO IT
DON'T DO IT
DON'T DO IT

[PhilipA]

Except for all the DON"T DO ITS Hook is correct.
When in Saudi I used to decant to my primus bottles as there were no Primus refilling facilities.
So you need a high pressure hose with the relevent fittings.
All you do is turn the bigger bottle upside down and pour the liquid into the smaller bottle until liquid comes out of the screw out valve. ( just like at the servo)
Just be sure you are outside and not in a hollow so the excess gas can escape.
Use gloves to hold each cylinder as they get bloody cold.

Remember it is dangerous. Oh its an idea not to smoke at the time.
Of course as indicated by the above posts this is against the Nanny State teachings, and you surely will die.
Regards Philip A

[landrovermick]

Originally posted by garrycol
With the advent of swap and go it is getting harder to fill my small gas bottles so I thought of decanting from my large lpg bottle.

I can connect both bottles together with the regulator removed but do I have to do anything special to get the gas out of the big tank to the smaller one. Someone has said the the bottle to be filled has to be lower than the one form which the gas is coming.

Any other tricks

thanks

Garry

Find a part of town where there is a large Asian population - Cabramatta in Sydney has the cheapest gas bottle refills around im told - in fact the servo on the corner of Hill ST and Cabramatta Rd keeps about 10 of the large filler bottles and a bloke whos job it is to just fill them - hes the bloke that was burnt during the War and is badly scarred - cruel and unusual punishment i recon!

Mick

[ianswalkingthedog]

Yes it can be done but is very much against the law, so dont get caught. As has been stated the bottles used for decanting are special. They have a tube which goes from the valve down to the bottom of the tank inside. This results in the internal pressure pushing liquid up the pipe through the valve. Other bottles do not have this tube and the pressure just pushes out gas (vapour). In theory you can achieve the same thing by inverting the larger feed bottle and cracking open the bleed valve on the bottle being filled. As the vapour coming out of the smaller bottle starts looking like white steam close the bleed valve, then the feeder bottle, then the bottle being filled. When you disconnect the hose do it with great care as the liquid in the line will expand and can cause a severe freeze burn. It can also ignite if you create a spark.

Some facts to scare the living bejesus out of you.

1 ltre of LPG weighs about .73kg. It expands to atmosherical pressure 250 times its liquid volume. It mixes with air at the ratio of 15:1 (air to propane) This means that the 1 litre of LPG has made 4000 litres of explosive gas. One spark and you are no longer in existance. Of course this does not happen all together there is a very short time where a thing called a BLEVE takes place (Boiling Liquid, Expanding Vapour Explosion). As the LPG expands into a vapour it mixes with the air. The expansion forms a shock wave in front which then hits an ignition source and the flame front expands even faster. The shock wave hits an object and blasts it out of the way (you). You are on the ground trying to breath but there is no oxygen available as the flame front consumes it all. You die of shock and suffocation. Then the flame front hits and incinerates you. the richer mixture following the flame front then ensures you are completely incinerated by feeding the fire of your body.

As was stated before DONT DO IT!

[weeds]

as everybody has said, it can be done quite easily but it would have to be as a last resort.

along with being against the law i would never consider doing it although we all probably stretch the law from time to time.

yep you need to turn the full cyclinder upside down , you can have it higher than the empty cyclinder however there is no need, crack the bleed screw on the empty cylinder, open the tap on the full cylinder, open the tap on the empty cylinder, turn off tap on full cylinder (upside down cylinder) when liquid starts coming out of the bleed screw, turn the tap off the empty now full cyclinder, tighten bleed screw when liquid stops and only gas is coming out.

last resort only