Anyone have any idea how low the pressure can go in a medium size O2
tank and still serve the needs of a Meco propane/O2 torch. Seems to
be that, at about 600 psi O2, my torch starts to act funny. Thanks.
Tank size is not relevant only the gas pressure. The Meco Midget
will work fine a very low oxy psi with propane or natural gas. It's
a great Torch. You should be using regulator settings for both
gasses under 10 psi.
Check both oxy regulator gauges for drift. If you use anti check
valves or flashback arrestors verify they are O. K.
Since you did not explain "act funny" maybe the oxy side is not the
problem? Does your Torch flame pulsate or flicker a little? Most
likely that is a propane tank or propane regulator problem. Likely
just coincidental with the oxy tank psi you mentioned. Did you
recently refill your propane tank? Is the propane tank located
outside in direct (summer) sun? Too cold winter locations are also
are not ideal.
I'd look at the propane regulator too. If it's O. K. I'd swap out
the propane tank. A different propane tank is often the fix and
usually no cost from the tank supplier. I'm assuming both gas hoses
are O. K. and tight.
If you're using Paige Tips on the Meco you have the ideal propane &
oxy setup. Paige Tips can be easily cleaned by boiling in water or
using an ultrasonic or steam cleaning. Air dry and you are good to
Again, my guess is it's not an oxy tank pressure issue. Could be an
oxy regulator issue a propane regulator issue or a bad propane tank
which is easily changed.
A safety tip that applies to all tanked fuel gas setups (acetylene &
hydrogen too!). Don't let the oxy tank psi get too low before
refilling. You don't want tanked fuel gas at a higher pressure to
ever leak back into the oxy tank via an open or defective Torch
valve or tank regulator. Say the propane tank had 60 psi (pressure
varies depending on propane tank fill and ambient air temp). If your
oxygen tank had run down to say 50 psi you would have an unsafe
situation. Same thing would apply to an oxy / acetylene setup if
either tank gets too low. You don'twant one gas to leak into the
other tank. If all valves and regulators are good and a person
bleeds both lines before & after lighting & at shutoff plus lights
their Torch correctly back leaking is no worry but sometimes
equipment problems happen or people get in a hurry and forget to
follow correct procedures.
Richard. My questions is relative to the O2 tank pressure as
indicated on the tank pressure gauge. Once the tank pressure gets to
about 600 psi, the quality of the flame produced on my Meco Midget
changes slightly. It tends to get less well defined and a bit
erratic. I usually run 5 psi for both O2 and propane at the torch. I
do use Paige tips and they are a vast improvement over the single
hole tips that shipped with the torch. I can adjust the torch
pressure to get a flame that works, but I am just curious what might
be going on at 600 psi and lower. I do have another O2 regulator and
can try to see if that makes a difference. I get about 6 months out
of a tank of O2, so it is no real inconvenience refilling it twice a
year, but I hate to waste good O2. As always, thanks for your advice.
Richard. As long as there isn't a problem with going below 600 psi, I
will make the adjustments to my Meco torch needle valve retaining
nuts that you suggest (I know that they are too tight), possibly
change the regulator, and see what happens. The propane tank is a
small 4 pound tank and was very expensive. I hope that it isn't
defective. Thanks. Rob