How low can you go?

Is there a lower tank pressure you don't want to exceed prior to refilling? Ox or Ac. I know with SCUBA, they ask that you return with 300psi to avoid the chance of moisture entering the tank. - Mike

Reply to
Michael Horowitz
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There is no discount for bringing a tank back with a few pounds left you still pay for a full bottle.

We routinely run the bottles empty with no complaints from the supplier.

Shielding gas on the other hand gets removed from the machine once it is below a hundred pounds. Only because you always run out in a corner where removing the porosity is the most difficult.

Reply to
John Noon

You shouldn't run the Ac empty or the acetone will enter and spoil your regulators. I try to keep and eye on the Oxygen pressure and not let it drop lower than the Ac working pressure JUST IN CASE.

Reply to
The Nolalu Barn Owl

The Nolalu Barn Owl

That's the factoid I was looking for - thanks, MIke

Reply to
Michael Horowitz

I've always used 40 Lbs for the Ac (never heard anything about Oxy before???). I have also heard 25Lbs on the Ac. The important things to remember are this:

1.) That funky smell isn't actually the acetelyene...it's the acetone. Ac is actualy oderless & the smell the acetone gives it helps you to know if there is a leak.

2.) Acetone (I'm told) isn't added everytime bottles are filled...thereby draining it could be a bad thing, as acetone also helps to stabalize the acetelyene.

3.) The reason acetelyene bottles can't be laid down & used is because the acetone seperates. Bottles that have been laid down must be stood upright for 1 hour (amount of time varies depending on who you ask) before being used.

4.) Acetone is bad on regulators that have neoprene (I'm a really bad speller) diaphrams.

-Wayne- P.S. You should see how the Kurds in Iraq get their Ac...it's really cool....and really dangerous.

Reply to
clutchglass

wrote: (clip) You should see how the Kurds in Iraq get their Ac...it's really cool....and really dangerous. ^^^^^^^^^^^^^^^^^ Aren't you going to tell us?

Reply to
Leo Lichtman

Oky doak Leo...here goes, Acetylene isn't a naturaly occuring gas...it's a compound made by inducing calcium carbide into water. A violent reaction takes place, and acetylene is emitted as a by product. Plants where acetylene is manufactured and bottled are almost entirely automated and it is a VERY dangerous operation. In fact, acteylene is so unstable it will actually blow up (without any source of ignition) once it hits 29 pounds per square inch. This is the reason an acetylene bottle is so much heavier than an oxygen bottle. In order to get more than 29 pounds of acetylene in a bottle...it has to be tricked. A large piece of balsa wood is placed in the bottle and the bottle is lined with celulose, next acetone is pumped in the bottle...and finaly (and slowly) acetylene is pumped in. What ends up happening is that the acetylene & acetone are obsorbed by the balsa wood like a giant sponge. The gas you end up using is then bleeded back out of the balsa wood. It should be noted at this point that there is a safe rate that acetylene can be bled out of the bottle....1/7th of the bottle's total capacity per hour...it should be further noted here that for this same reason "rose bud" heating tips are NOT supposed to be used with single acetylene bottle set ups. They can only safely be used with manifold systems that incorperate multiple acetylene cylinders. O.K. now that I made you suffer through that class (too many years of teaching soldiers & oxy/acet is my favorite class) I will tell you about the Kurds as promised. In April of 2003 (until November) I went back to Iraq (Did the 1991 gulf war also). I ended up with a really unique assignment living amongst the Kurds (with very little military around) and running a Kurdish shop building machinegun mounts. Iraq's only acetylene plant was blown up in the 1991 gulf war & never got rebuilt. The Kurds go to the general market (hooches set up on the side of the street) and buy "the carbone" as they call it. They bring it back to the shop...open up this funky looking little drawer/box thingy with the acetylene hose coming out of the top...poor some water in...whack off a piece of "the carbone" & chuck it in the water...close & seal the drawer..and it emits acetylene to the torches. Get the wrong mixture of "carbone" & water...or (God forbid!) there is rain & the "carbone" gets wet....& LOOKOUT!!!! Kablooy!!! Hope this was all more interesting than boring.

-Wayne-

Reply to
clutchglass

Reply to
Robert Ball

Wayne, Interesting experience, thanks! You should consider putting your experiences together into a book. I think you would do well.

My grandfather had an Acetylene generator when I was very young. It used calcium carbide granules in a container in the bottm and water in a container in the top. The water dripped into the calcium carbide at a rate controled by a valve, much like a large version of the old carbide lamps the miners used. I got to play with the "majik rocks" and make all sorts of interesting smoke and flames and an occasional bang. A mason jar with enough gravel in it to make it sink, some water and a handfull of calcium carbide makes a respectable depth charge :)

Reply to
Glenn

would be cool to see some pics.

b.w.

(nice story, thanks. i hope you have a favorable opinion of the kurds and iraqis in general.)

Reply to
William Wixon

William, I became VERY close to the Kurds. I had two bodyguards who layed thier life on the line for me several times. If someone can explain to a newby how to attach a file in this news group, I'll shoot out a picture of the whole crew: Me- CW3 Glass My Sergeant- Terry Hulett My Interpreter- Nazradean...aka "Naz" Body guard- Amin...aka "Jed Clampet" Body guard- Sharzodt...aka "James Bond"

Reply to
clutchglass

There are lots of places to upload photos. Once you've done that, you can put a link to the location in your message. Here's one place (I've never used them, but it looks easy enough)

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If you have any trouble doing this, just email me the photo and I'll take care of it for you.

(another) Wayne

Reply to
wmbjk

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