Torches can flame without propane tank connected!

It seems to really confuse someone who -

Says he doesn't own a torch. Doesn't know how they work. Refuses to believe that those of use who DO own these torches and actually use them know anything about them. Thinks that when we actually test them out and cannot duplicate a video, that WE must be the ones who are wrong. And who hides behind a fake name---

HMM sounds a LOT like another dipstick we all know on here--- J.B.

The left tried very hard to roast Reagan for smuggling arms to the Contras but indignantly dismisses allegations that they did the same thing as a partisan witch hunt.

Err... doesn't propane boil at something like -43 (F)? How cold does it get there in YouTube land?

John B. fired this volley in news: snipped-for-privacy@4ax.com:

Err.... at atmospheric pressure! Wanna just guess that the pressure in the tank and torch inlet tube is higher than at atmospheric pressure?

You DID know that the propane in a tank is typically in a liquid state; yes?

Lloyd

The Engineering Toolbox* gives the vapor pressure of propane at 70F as

So with a warm tank at 70 & a cold torch at 0, there would be 90 psi difference pushing propane gas into the (off/closed) torch. The warm gas will quickly fill the chamber and equalize the pressure, but that pressure will be higher than the vapor pressure of the cold chamber and the propane will start condensing.

Equilibrium will reached when the chamber and tank temperatures are the same. The tank will cool from vaporizing liquid (and from being in 0F air) and the torch will warm from condensing vapor. How much propane that will take depends on too many things for me to even guess at, but the end result will be liquid propane in the torch chamber.

Bob

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Gunner Asch fired this volley in news: snipped-for-privacy@4ax.com:

THAT particular head has a tube about 1/8" i.d., and about 1.4" long from the tank to the valve. If that were filled FULL of liquid (only), it would burn about 0.9 seconds. Remember, he didn't have just a "lick" of flame burning on that thing -- it was at full blow torch volume.

That particular head has NO 'chamber' or special "vaporization area". It's just a straight tube up to the valve. There's a sintered metal filter downwind to reduce the pressure, so that the gas will vaporize.

THAT head won't burn that long off the tank, no matter what you do, short of 'processing' the video. I have two. I've used them in every position, weather, and application to which you could apply a B-O-M trigger torch.

Lloyd

Yes, the vapor pressure at +50 (F) is ~100 psia. So?

And you close the valve... what is the pressure on any gas remaining in the torch tube?

The question might be raised about how do you arrive at a 70 degree(F) tank and a 0 degree torch? :-)

Easy easy. Just have gas stream from the nozzle without a flame. It gets cold... The tank in your hands is soaking heat from your hands or gloves... Sun lights and a long list.

Mart> >

John Doe fired this volley in news:n0n0lb$oa5 $ snipped-for-privacy@dont-email.me:

It's even worse if you fall into a pond while wearing propane-soaked clothing. You can freeze SOLID in just seconds!

I don't know about propane torches but I did see a warning notice for welders. Apparently sparks ignited the throw away plastic cigarette lighter in a couple of welders breast pockets, so the notice suggested that you not carry your lighter there :-).