Refilling 16 oz propane bottle off a 20# tank

[NinerBikes]

I am missing the instructions on the procedure of how to do this, after buying the thread adapter to do so.

Could someone walk me through the procedure?

I assume I need a bleed off valve that works on the 16 oz bottle to bleed off propane in gas form to let the liquid form in from the 20 pound bottle?

Do I invert the big bottle so it flows liquid or keep it upright and let it flow in gas?

[NinerBikes]

New York boneless steak was delicious, and I didn't blow myself up this time. Will be careful, thanks for all the pointers and suggestions.

[NinerBikes]

[NinerBikes]

[NinerBikes]

got a 16 oz can in the freezer, going to do a couple of steaks tonight. Be thinking of all of you as I smother it in A1 Hearty Steak Sauce, chew it up and swallow it down... better tasting than most steak houses that bone you $25+ for a steak dinner. Salud!

[red31]

bradykeverytime wrote:
we went south people were waiting for us Canucks to be blowing ourselves up.

my insurance rate was the same when I went dual fuel. 30 degrees north, 200 psi vapor pressure in the heat of the summer, of course at the bottom of the tank the pressure was higher.

[bradyk]

Not to go too sideways but wow on the propane issue for you guys down south. I remember back in the day up north we were running cars, trucks and everything on propane and everytime we went south people were waiting for us Canucks to be blowing ourselves up. Propane has been around for a long time and as available up here as gasoline. Take care, do what you are supposed to do and it is a great fuel. Maybe some day southerners will get have propane refills on every block as we do and realize it is safe. Natural gas is the next big thing that seems to be coming so get used to it.

[Almot]

In some places (most of Mexico is such a place) small green cartridges are a rarity. And cost double, compared to the US.

So, Mex - cheap reliable scale for 16 oz? My only scale is a spring fisherman scale with +/- 3 lb accuracy 🙂

[MEXICOWANDERER]

It matters utterly on whether LPG/Air achieves optimum stoichiometric proportion. A 40 lb cylinder would blow a house to utter palm-size rubble and blast a shallow crater about 50 ft in diameter.

A regular TNT explosive creates a shock wave perhaps a foot wide at 50 ft. A FAE shock wave is 10 times as wide. 2,000 lb FAE bombs destroyed everything in tunnel networks in Afghanistan, multiple tunnels up to THREE KILOMETERS from point of detonation. Inside a tunnel more than 2 MILES away, victims exited the tunnel in excess of 200 mph. These things AKA "Thermobaric Bomb"

Don't fear it, respect it.

Someplace I had a small box of knurled brass caps with seals for bottles. Hope they're still there.

[SaltiDawg]

westend wrote:
...That's not the answer I get but is somewhat immaterial. If 8 million gallons of propane starts igniting, I don't want to be anywhere close.

Yeah, that's actually something over 15,000 Tons. In wartime worth a torpedo. 988 Tons not worth one. (Saith the retired Submariner. :B )

[pnichols]

Almot wrote:
To people wondering why small camping cartridges at all. To use with small camping stoves. Duh. Not everybody is staying within 5 ft from their rig at all times. People go boating, biking, kayaking. And as a backup to big tank, too.

That's why I just buy the little green bottles for our RV's Weber from Walmart for ~$3.08 each. So far they've always been full all the way to the top. 😉

I guess the main rub is that you have to drive to a Walmart to buy them ... no ordering over the Internet (at least not here in CA). 😉

[2oldman]

westend wrote:
The cloud of propane that came out of those suckers was a thing to behold, massive.

I bet. Gives you an idea of the almost unimaginable energy released in an atomic explosion.

[westend]

2oldman wrote:

westend wrote:
Two 100,000 bbl tanks = 200,000 bbls. 8,400,000 gals.

Propane at 4.25lb/gal, that's 988 tons, give a ton or two.

I dunno the comparative energy in a pound of propane vs. pound of TNT, but there it is. That's a long way from 15,000 tons.

That's not the answer I get but is somewhat immaterial. If 8 million gallons of propane starts igniting, I don't want to be anywhere close.

Before the owners installed a cooling/pressurizing plant onboard, there was a lot of "white knuckling" watching cargo temps and tank pressures. The tanks were set up with automatic relief valves, a set of ten or so 6" pipes that would evacuate pressure when it reached a certain threshold. The cloud of propane that came out of those suckers was a thing to behold, massive.
At certain times, when pressures were close to the relief threshold, we would hang a 10" cargo hose over the side and relieve some pressure. It was a better situation than trying to steer away from that cloud of gas.
After the cooling array was installed, we didn't have any of those discharge issues. I also learned that a dozen cases of beer could be chilled in a few minutes by discharging through the 3/4" inspection/sampling valve. Just had to keep the deckhands away with their chipping hammers until the propane "iceberg" melted away.

[MEXICOWANDERER]

Vapor Pressure (psig)

Mixture Propane (C3H8)

(%) 100 70 50 30 0

Butane (C4H10)
(%) 0 30 50 70 100

Temperature

(oF) -44 0 0 0 0 0

-30 6.8 0 0 0 0

-20 11.5 4.7 0 0 0

-10 17.5 9 3.5 0 0

0 24.5 15 7.6 2.3 0

10 34 20.5 12.3 5.9 0

20 42 28 17.8 10.2 0

30 53 36.5 24.5 15.4 0

40 65 46 32.4 21.5 3.1

50 78 56 41 28.5 6.9

60 93 68 50 36.5 11.5

70 110 82 61 45 17

80 128 96 74 54 23

90 150 114 88 66 30

100 177 134 104 79 38

110 204 158 122 93 47

MAYBE THIS IS EASIER

Scroll Down For Butane/Propane Temperature CHART


The bottle fill I did last week was from a 20 lb pot pressured to 87 lbs if memory serves me right. Mexico has butane at lower and warmer climes. When temps approach 10c Propane is added. At 5c Pure propane gas. At < -10c up to 3% methane is added. I use a glycerin-filled Ashcroft 0-300 PSI gauge.

BOTTLE (Disposable)

POT (Refillable 3-20 lbs)

CYLINDER (refillable 40 - 200 lbs)

TANK (refillable above 200 lbs capacity)

BULK TRUCK (Six wheel dispensing truck)

TANKER (TRUCK & TRAILER(S)

***Refer To Table Above***

As you can see at high temperatures, propane pressure can get rather rude.

[Almot]

MEXICOWANDERER wrote:
Use a scale. With tare. Overfilled bottles will indeed go overpressure and vent if overfilled and temperatures climb. The 16 oz limit is hard and fixed.

I trust the "hissing stop", and then push the rod on the main port for a few seconds, to let out some.
What scale do you use, that is accurate at 16 oz won't go belly up within a year?

To people wondering why small camping cartridges at all. To use with small camping stoves. Duh. Not everybody is staying within 5 ft from their rig at all times. People go boating, biking, kayaking. And as a backup to big tank, too.