OXYCON - PSI vs LPM

[buckey29]

I have a Bobcat torch running on 2psi of LP. My oxygen is an M-10 (5LPM at 10PSI) from Unlimited Oxygen.

I'm trying to make sense of the O2 thats being delivered to my torch. I've been told that 2PSI on the LP is what you should use, but what about the O2?

If I were using an M-5 (5LPM @ 5PSI) vs a M-10 (5LPM @ 10PSI) would I notice much difference since there is basically the same volume of air in a given period of time?

I also know that I've been told that with an Oxycon you should run with the oxy knob opened up on the torch so you don't generate any back pressure on the Oxycon, which is what I do. Any other thoughts or suggestions to help me?

Oh, also, if I got a 2nd Oxycon, how do you connect them? Would it work on a torch lke the Bocat or would you need a torch that had multiple inlets for O2?

Thanks!

[Dale M.]

I have a Bobcat torch running on 2psi of LP. My oxygen is an M-10 (5LPM at 10PSI) from Unlimited Oxygen.

I'm trying to make sense of the O2 thats being delivered to my torch. I've been told that 2PSI on the LP is what you should use, but what about the O2?

If I were using an M-5 (5LPM @ 5PSI) vs a M-10 (5LPM @ 10PSI) would I notice much difference since there is basically the same volume of air in a given period of time?

I also know that I've been told that with an Oxycon you should run with the oxy knob opened up on the torch so you don't generate any back pressure on the Oxycon, which is what I do. Any other thoughts or suggestions to help me?

Oh, also, if I got a 2nd Oxycon, how do you connect them? Would it work on a torch lke the Bocat or would you need a torch that had multiple inlets for O2?

Thanks!

LPM is Liters Per Minute... It is a measured amount of volume.... Its just like your lungs you inhale and exhale a certain VOLUME of air each time you breath. This can be measure in liters per minute, in fact many respiratory medical tests actually do this....

PSI is Pounds per Square Inch... It is the force that pushes the oxygen (or most anything for that matter) out the end of a hose...

Think of the concept of a water hose.... The more volume the hose is capable of carrying (lpm) and the more pressure behind (psi) it the BIGGER the stream of water....

Dale

[buckey29]

Dale

Thanks for the reply. Actually, I understand LPM (Volume) and PSI (Pressure). Thats the part that I don't have questions about.

Let me try to ask differently......

With my Bobcat torch I use 2PSI of LP. What is the proper PSI of Oxygen that I should be using? My oxycon is 10PSI (@ 5LPM). I'm not sure I can adjust the PSI but I can the LPM.

And the other quesiton was about how to add a 2nd oxycon.

[kbinkster]

I have run a Bobcat on a 5 psi Invacare set to 5 LPM and on an 8 psi Regalia set to 5 LPM and have seen no difference in the flame. This may be due to the fact that static pressure (the psi ratings we see on concentrators) is different than running pressure and the running pressures of the machines may be similar to each other.

Wally tested the Cricket on a DeVilbiss (5 LPM at 8.5 psi static pressure) and on an M-10 (5 LPM at 10 psi static pressure). The Cricket actually ran better on the DeVilbiss than it did on the M-10. I think the running pressure was 1.5 psi on the DeVilbiss and 1 psi on the M-10. That's a difference of a third of the psi. Anyway, for those particualr machines, there was a noticable difference. I would like to eventually test a Regalia, a DeVilbiss, and an Invacare to compare them, but I don't have a DeVilbiss over here (yet).


Anyway, I'm sure you have heard of ratios like 1 part fuel to two or three parts oxygen for your flame mix and that may be why you are asking your question about how much oxygen to use with the 2 psi LP. Really, you don't need to worry about that unless you are running your valves wide open at the torch. You ultimately adjust what gets into your torch by the torch valves.

You can run a Bobcat on 5 LPM for soft glass and small boro. Adding more oxygen allows
you to work hotter/faster. You shouldn't need more than 10 LPM to gt the full range of the torch.

When adding a second concentrator, you really want them to be within 2 psi of each other. Otherwise, one pressurizes the line and the other backpressures itself because it can't push it's oxygen into the main line.

[buckey29]

Thanks Kimberly.

You said "You ultimately adjust what gets into your torch by the torch valves". Understood, hence the knobs on the torch. <Smile> however I've had multiple people say that when running an Oxycon, you should leave the oxygen all the way open so you don't create back pressure as it will damage the oxycon. Did I misunderstand that?

Also, the reason I asked about a 2nd oxycon is because I may want to upgrade to a Lynx at some point. If I do, I thought I might add another M-10. From your comment it sounds like I can just use a "y" adapter and I will be fine if I do that.

[Hayley]

I have two M15s Y-ed together for my Barracuda and I do not open the oxy valve of the torch all the way open at all. I believe that you only need to keep it cracked opened a bit when the oxycon is on to eliminate back pressure.

[kbinkster]

Hayley is correct, you don't need to have your oxygen valve open all the way to keep the oxycon from back-pressuring. On the 5 LPM oxycons, as long as the flow meter ball is not resting on the bottom of the flow meter, you should be o.k..

When adding a second unit, you could add another M-10 or even a DeVilbiss, because the pressure outputs are close enough. I would not suggest adding an M-5, an Invacare, or an AirSep to an M-10.

[buckey29]

Kimberly and Hayley -

Thanks! Thats exactly what I needed. As a newbie I may have misinterpreted what I was told about that before. So now I'm thinking....if I added a 2nd M-10 I wonder what torch I should get <GRIN>