Oxy concentrator question

[JoeWokovich]

Originally Posted by ditfd

Joe: I used an Alliance oxycon unaltered, used, from a medical supply place for 5 or 6 years, no problems. Paid $150 for it. So far, it has been the one that's had the best track record for me, so if you can get one from your neighbor's basement, ............Patti

Thanks Patti,

I hoped that the med ones where capable of torch work and you and Kim have verified this. I'm waiting for my neighbors wife to come back home and then check to see what type they have in the basement.
One thing we do have here in St Louis is humidity and the last couple of days the poor quality clean air alert has been up.
It seems that $150 is a going rate on Craigs list around my area with Invacare being the most common.

Joe

[ditfd]

Joe, I work on a minor, so a 5 lpm machine should work for you if you're using a minor. I can't speak for any other torch. Whoever suggested earlier in this thread if you can test before you buy, that would be good. Better check/clean the filters too.

Best,
Patti

[JoeWokovich]

Originally Posted by ditfd

Joe, I work on a minor, so a 5 lpm machine should work for you if you're using a minor. I can't speak for any other torch. Whoever suggested earlier in this thread if you can test before you buy, that would be good. Better check/clean the filters too.

Best,
Patti

Patti, from what I remember the machine was new when he got it and there is only something like 4,000 hours on it. But I have to wait until I can see it.

Yep, that's what I bought was a 6 month old minor with the creation station and hoses and a propane reg. for $200. There isn't even any burn marks on the station and the tip still looks bright and clean with very little heat discolorization. I think I got a good deal.

Joe

[sarbeardog]

Hi Patti,

Thanks for the info.

Here is the sum of what I read and understood.

If the flame is what I want and the concentrator gives me more oxygen when I ask for it, then its safe to assume that the concentrator is working the way that it should. I'm happy the concentrator is happy and my torch is happy!

the LPM and purity are basicly one and the same. LPM is the flow and the purity is the amount. The purity is not how clean the oxygen is coming out of the concentrator but the amount the concentrator is generating

Please correct me if I'm wrong in my summing up
thanks
Kathy

[pam]

Patti has done a great job of explaining all this, but your last statement seems just a little off, and perhaps it's my misunderstanding. However, for clarification for myself, anyway, although the concentrator may be putting out the volume of flow that you want, that flow may not be as oxigenated as it needs to be. Perhaps it is 79% oxygen and 21% air, which would not give you what you need for a clean burning torch.

[Mr. Smiley]

The thing that kinda bother me is this... Kimberly tested UO units that were known to be bad units. The results on all of the machines she tested were not up to the specs posted by their manufacturer. I'd like to see a Regalia turned up to produce a true 10 LPM on her analyzer. What would the purity on that machine be then?

I know without a doubt in my mind that UO units are a fine choice. How do I know? I use them myself. I would NOT use anything substandard. This is my full time occupation. I have sold hundreds of them to friends and other lampworkers and they are working in their studio as well. I get emails and PMs from customers thanking me all the time. If the negativity surrounding these units was coming from anybody other than my competition or people with a grudge, I wouldn't sell them...

My opinion of these units is not based on a need to sell them... I could honestly care less about selling concentrators. I do it because I believe these units are the best solution for most lampworkers. If my sales dried up and went away, I wouldn't shed a single tear, but I do think the lampworking community as a whole would suffer a loss. UO has provided us with something no other company has done before. It's an affordable way to power our torches at the volume, purity AND PRESSURE we need. If there is ever a problem with a UO concentrator, the company will stand behind it and make it right. Period.

People have come forward with good experiences, but I'll assume that most of the happy customers are melting glass and they really have no need to pay attention to this type of thread. Why would they?

If you're new to all of this, then gather as much information as you can before passing judgment. There are some personalities involved that have a history and you should consider the source of the information...

much love...

[ditfd]

Hey Kathy, what Pam says is correct. It's possible to have lpm/psi flowing through your torch, but without enough purified oxygen. So lpm is NOT the same as purity.

Lpm = liters per minute (volume)
psi = pounds per square inch (at what pressure)

the two above measurements have nothing to do with the purity of what's going through at what pressure. It's a separate consideration.

Make sense?

Patti

[ditfd]

So Dennis, I guess those of us with bad oxycon experiences should do what then?

Patti

[ditfd]

Also, Dennis, I wouldn't say I have a grudge. I make a living at this, and I need this very expensive piece of equipment to do what it's supposed to for as long as it's supposed to without the constant hassle of having to hassle the oxycon guy, box it up, get it shipped, wait for repair/replacement, unbox, hook up, test. All to be repeated in another 6 months?

I had hoped you and Jack would want to discuss WHY this might be happening, and help to solve the problems I've had for once and for all without needing to do the song and dance described above.

I've said before, I have my own theory, but you and Jack have yet to ask.

I'm making my future decisions based on my personal experience with these products as well as the info I can get from these postings, minus the interference you seem determined to propigate.

Kimberly has tested units in the field. After they've been set up and used under a variety of circumstances with a variety of torch/oxycon configurations.

Perhaps she could use some help, and you could contribute actual numbers to the discussion, rather than the very subjective, "It works for me."

I'm here to say "It hasn't worked for me." Twice.

Patti

[Mr. Smiley]

Patti, I'm a little offended that you're calling me Dennis. I'm Brent. One of the very few things Dennis and I have in common is that we both sell UO units. I hope the similarities end there.

I can tell you that Jack has listened to the lampworking community. There is ongoing testing all the time. If something fails, it is broken down to see what failed. The modified UO units have not been without problems. It's something new and if it wasn't working a lot more often than not, it would be an idea that got scrapped a long time ago. If you have a theory, I'm sure Jack will listen to it. I've given Jack a ton of feedback. Both good things and bad. That's where my involvement in the factory aspect ends. I'm just a reseller. I have no control over the manufacturing process... I am how ever really impressed by the way Jack listens to the community when he's presented with information or a need we have.

UO is a company I've seen go above and beyond to give lampworkers what they need. There is not one single unit Kimberly sells that would fill my oxygen needs. I could spend $3000 with her and still not have what I've got now... I paid $1600 for my units 2.5 years ago and they are still going strong. No service no nuttin. I hope that some day every single UO customer has the same exact experience... and they are working really hard to ensure that...

[Mr. Smiley]

Originally Posted by ditfd

So Dennis, I guess those of us with bad oxycon experiences should do what then?

Patti

Speak up... like you are. Jack is listening.

[ditfd]

Sorry Brent. For some reason, I honestly get you two mixed up in my head all the time. Hopefully, I'll keep it straight from now on, especially on the forum.

Again, no actual stats though. Just the little dig at Kimberly?

Look, I had the M10 for about 2.5 years. Then it went kablooie.

I had the M15 for less than 6 months. Then it went kablooie.

Both lost oxygen purity long before they went kablooie. And I did a meticulous job keeping up the filters.

Jack has already said he'll replace it if I get around to shipping it to him.

That's not the only issue, though, or even the important issue.

To me the issue is WHY. If that can be answered, then we'll all be better for it.

I honestly don't think that UO's oxycons are "worse" or "flawed" than somebody else's oxycons. What I do think is that it's pretty dang hard to make a decision for which oxycon may or may not be right for a given artist. And in my case, there's probably a logical explanation for WHY these have not worked FOR ME.

You guys are in the bus to sell me the biggest, baddest oxycon money will buy. I get it. But therein lies the flaw. Bigger may not be better in all cases.

So, having kept up with these threads, I have a pretty good idea who I will be doing business with in the future. It's going to be with somebody who is as interested as me in finding out the WHY when something goes awry.

And again, I have my own theory about my own experience with the UO's, but obviously, the WHY is not important to you all. Picking at each other is alot more constructive, eh?

This is why Kimberly's info is valuable. You guys could provide the same type of measurements with your customers configurations, so that we could start a database of torches and oxycons. That way, and again!, people could make an informed decision about a configuration that would work best for them.

Seems so simple! And yet?

Here's what would be on my chart to start with:

1.) lpm/psi/purity as advertised
2.) lpm/psi/purity as tested at the studio of an artist
3.) torch
4.) altitude
5.) humidity
6.) months is use

Patti

[sarbeardog]

this is what I may have been trying to say.
If the flow is correct, PSI is correct but the purity is not....
What is happening? Carbon build-up faster? Glass color issues? heat issues?
Does anyone know what the purity of tanked oxygen?
Thanks Pam for helping me out with the words need.
Kathy

Originally Posted by pam

Patti has done a great job of explaining all this, but your last statement seems just a little off, and perhaps it's my misunderstanding. However, for clarification for myself, anyway, although the concentrator may be putting out the volume of flow that you want, that flow may not be as oxigenated as it needs to be. Perhaps it is 79% oxygen and 21% air, which would not give you what you need for a clean burning torch.

[Dennis Brady]

Kimberly has tested units in the field. After they've been set up and used under a variety of circumstances with a variety of torch/oxycon configurations.

Perhaps she could use some help, and you could contribute actual numbers to the discussion, rather than the very subjective, "It works for me."

I'm sure I, and the 100 or so pro artisans I regulary work with, could help and could provide excellent information. However, the operative term here is "subjective". To be universally valuable, test results must be objective. Kimberley has used every possible opportunity to denigrate Unlimited Oxygen. As a result, I would always be suspicious of any data she supplies and expect that data to be more subjective then objective. Until somebody steps up that doesn't have a dog in the fight, I'll rely exclusively on the information I get from my own tests and from independent unbiased users.

[Mr. Smiley]

You keep saying the "why" isn't important... did you read my first post? It is VERY important. Jack has done and is doing every thing he can to make constant improvements.

I don't want to sell anybody any more concentrator than they need, but I also want the larger options available to those of us that DO need it. I couldn't work on anything less than what I have. You took my post as a dig on Kimberly. It wasn't at all. I just showed that even with $3000 laid out, I can't get what UO has given me. That doesn't hold true to just the regalia... it's ANY company other than UO.

If all you need is 6-8 PSI, I say go for a medical unit... and if you need more than 5 LPM, just get more than one.

If you need more than 6-8 PSI, then you need to look at alternatives and UO is the only affordable choice... especially when you get up around 15 PSI.

[Dennis Brady]

Originally Posted by Mr. Smiley

Patti, I'm a little offended that you're calling me Dennis. I'm Brent. One of the very few things Dennis and I have in common is that we both sell UO units. I hope the similarities end there.

I can tell you that Jack has listened to the lampworking community. There is ongoing testing all the time. If something fails, it is broken down to see what failed. The modified UO units have not been without problems. It's something new and if it wasn't working a lot more often than not, it would be an idea that got scrapped a long time ago. If you have a theory, I'm sure Jack will listen to it. I've given Jack a ton of feedback. Both good things and bad. That's where my involvement in the factory aspect ends. I'm just a reseller. I have no control over the manufacturing process... I am how ever really impressed by the way Jack listens to the community when he's presented with information or a need we have.

UO is a company I've seen go above and beyond to give lampworkers what they need. There is not one single unit Kimberly sells that would fill my oxygen needs. I could spend $3000 with her and still not have what I've got now... I paid $1600 for my units 2.5 years ago and they are still going strong. No service no nuttin. I hope that some day every single UO customer has the same exact experience... and they are working really hard to ensure that...

My most recent experience with Jack's customer service was the best that could ever be imagined.

We supplied an M15 to a customer on Hornby Island (Google it to see where it is) that makes his living making and selling torchworked glass. The huge majority of his income is during the summer months from tourists. His machine wasn't performing up to standard and lack of oxy capacity was severely hurting the income he and his family relied on to get through next winter. Jack immediately dispatched a replacement - at no cost to the customer.

I've been in a number of different businesses for 50 years and consulted for dozens as a management consultant. All my experiences with Jack have demonstrated the most personalized and most reliable service I have ever experienced. I consider it a priviledge to work with him and his wife to sell their equipment. I wish more of my suppliers where as steadily dependable.

As both a business entrepreneur and a business consultant, an important lesson I learned long ago is that a detailed contract isn't nearly as valuable as the honour and ethics of the people you do business with. The technical specs aren't nearly as important as the willingness of a supplier to make good if there becomes a problem. Whether you sell a product or a service is irrelevant. What matters is what support you will provide for what you sell. My experiences with Jack have always been first class - and it's obvious from the great many supportive comments made by others, that many others have had the same experiences.

As a comparison, I had a recent experience with a customer whose 4 month old Paragon kiln controller malfunctioned and caused a runaway firing that totally destroyed a quantity of molds, the kiln shelf, and ate a large hole in the kiln floor. Paragon provided a replacement circuit board but refused to be responsible for the damage caused by their defective controller. I will in future continue to do business with Unlimited Oxygen, but NEVER will I have anything to do with Paragon kilns.

The measure of value isn't whether or not something goes wrong, but what you do if, or when, it happens.

[Blueflameart]

Things that make you go hmmm.

If you're new to all of this, then gather as much information as you can before passing judgment. There are some personalities involved that have a history and you should consider the source of the information...

Should I guess at who this is pointed at or should we just say if the shoe fits ....

I'll await your answer because if your "new to all this" ... well lets just say we can shed light on any corner your coming from ...and thats to you or Dennis or anyone else that's involved.

NO matter what is typed ... no matter what is said you and Dennis fall back on the same ole same ole and it goes back around like a dog chasing it's tail ... the pick shots you guys take are getting old. I'm not trying to pick on any ONE person yet everything you guys type makes anyone other then yourselves look like the bad guys.

Now most, like Joe, see just where the piss and venom comes from ... not just you mind you, I'll step up anytime I need to.

Stop all the cheap shots and keep this on track and I will do the same.

[Blueflameart]

I will have to add this ... a machine is a machine ... it does one thing ... it does it good or it does it bad ... the inner working of these machines, from what I've read and heard, are complicated so who's to say what the problem is?

This is what keeps us, the ones that WANT and NEED to know, before we go out and shell out the money to buy these units. It's important to us and I know everyone should think from now on before typing and if it's something that has nothing to do with the subject matter, take it to email, pm's or another thread, ME INCLUDED!

[sarbeardog]

help!
No response on question about purity? Just back and forth about the same old thing!
I'm not intersted in who said what and when.
can someone bring this post back to information about concentrators, facts and a simple answer on purity and the concentrators!
Thanks

[Blueflameart]

Originally Posted by sarbeardog

Hi Patti,

Thanks for the info.

Here is the sum of what I read and understood.

If the flame is what I want and the concentrator gives me more oxygen when I ask for it, then its safe to assume that the concentrator is working the way that it should. I'm happy the concentrator is happy and my torch is happy!

the LPM and purity are basicly one and the same. LPM is the flow and the purity is the amount. The purity is not how clean the oxygen is coming out of the concentrator but the amount the concentrator is generating

Please correct me if I'm wrong in my summing up
thanks
Kathy

I'm not the expert Kathy but from my findings purity and LPM's are not one in the same ... from what I've heard a 5lpm machine is putting out about 2.5psi give or take? So if you take my setup which is 2 - 5lpm machines with both set to 4 liters per the gauge I should be getting roughly 6-7 psi and around 92% purity. I've read that I should pump both machines up to 5 lpm, the max and get about 85% purity. The purity IS the amount of clean, pure oxygen your getting out of your unit. The PSI is just the amount of "push" your getting through the lines.

I'm sure Kim or Jack or maybe one of the others will jump in and give the correct numbers. I've seen just what it's like working on Invacare's, M-15's and now tanked and it's all night and day. If you've got nothing to compare to it's so hard to tell whats what ... but if you get a chance to work on all these unit's you would see it like night and day, both the good and the bad. Nothing will ever touch tanked oxygen but for the buck nothing will touch these concentrators either such a double edged sword. GL!

[pam]

Originally Posted by sarbeardog

this is what I may have been trying to say.
If the flow is correct, PSI is correct but the purity is not....
What is happening? Carbon build-up faster? Glass color issues? heat issues?
Does anyone know what the purity of tanked oxygen?
Thanks Pam for helping me out with the words need.
Kathy

Sorry, Kathy, I haven't been on in a few hours, so "what is happening"? The carbon will build up faster on some torches, but not on others. It will depend a lot on the flame chemistry of the torch you own. Colors that require an oxygenated flame to develop properly will not develop, or perhaps you can get it to work by turning your oxygen source way up outside of the normal flame configuration. Heat is another side effect. Oxygen helps the propane flame to burn hotter, to a certain point, cooler beyond that effective point. If you are not getting the correct flow of oxy, then the flame will be cooler than normal and your glass will not melt as fast.

I didn't answer your question on the purity of tanked oxy because I couldn't recall the exact number, but from my memory it is somewhere in the 97 to 98 percent - perhaps even 99. I'll do some research and see if I can get you and exact answer to the oxy percentage on tanks.

[sarbeardog]

Originally Posted by pam

Sorry, Kathy, I haven't been on in a few hours, so "what is happening"? The carbon will build up faster on some torches, but not on others. It will depend a lot on the flame chemistry of the torch you own. Colors that require an oxygenated flame to develop properly will not develop, or perhaps you can get it to work by turning your oxygen source way up outside of the normal flame configuration. Heat is another side effect. Oxygen helps the propane flame to burn hotter, to a certain point, cooler beyond that effective point. If you are not getting the correct flow of oxy, then the flame will be cooler than normal and your glass will not melt as fast.



I didn't answer your question on the purity of tanked oxy because I couldn't recall the exact number, but from my memory it is somewhere in the 97 to 98 percent - perhaps even 99. I'll do some research and see if I can get you and exact answer to the oxy percentage on tanks.

Thank you Pam for info. You made it clear.
Kathy

[pam]

Actually, Kathy, I just found the material I was looking for and tanked oxy is 99 percent pure. I hope that helps.

[kbinkster]

Originally Posted by Mr. Smiley

The thing that kinda bother me is this... Kimberly tested UO units that were known to be bad units.

Which units were those, Brent? And "bad" in what sense?

I tested two UO units and two EO units. The M-15 and EX-15s were not known to be "bad" units, or otherwise not delivering the LPM, purity, or psi they were advertised to deliver.

If someone gets a machine and they are not happy with it, that does not automatically mean that the machine is "bad." It could be different from what the buyer was expecting or wanting, but still be in good working order and within the specs of the manufacturer.

The M-20 that I have here that I tested did not work like I wanted it to work. The flame looked too weak/cool, but I thought the pressure was fine. It did not perform like the demo machine they had at the St. Louis Gathering, but that did not mean that it was not doing what it was built to do. When I saw the specs that were in the "manual" for the M-20, which were pretty low purity, I figured that the machine still may very well have been performing to UO specs, even though those are not to my standards and were not the same as what SCC/UO originally told us to expect from their 10 LPM/20 psi unit when they were trying to get us to buy a bunch and become distributors. (Bait and switch?)

But, here's the important part, read carefully - I had no idea that that M-20 I had here did not perform to the UO specs for that machine until I tested it with my analyzer.

Originally Posted by Mr. Smiley

The results on all of the machines she tested were not up to the specs posted by their manufacturer.

No, only the UO/EO units and the broken DeVilbiss were out of spec. The Regalia, Integra10, and Invacare were just fine. I will be sending out my machine to be testing more units, so we'll see what happens.

Originally Posted by Mr. Smiley

I'd like to see a Regalia turned up to produce a true 10 LPM on her analyzer. What would the purity on that machine be then?

I cannot push the Regalia over 10 LPM (one of its features to prevent it from being overflowed), so I tested my Integra10 this morning. I ran it so that the mass fow reading was 10 LPM. The volumetric flow was unreadable on the machine - probably over 11 LPM. The purity is about what I would expect for this altitude - around 89.9%. It would dip down to 88.8% and go up to 90.5%.

This is much better than what I found for the M-15 at this altitude, and I didn't even push the mass flow to the rated 8 LPM.

Flow Rate set on machine: 10 LPM (volumetric flow rate)
Flow Rate read by analyzer: 6.9 – 7.6 LPM (little lower than expected for this altitude) (mass flow rate)
Oxygen Concentration (Purity): 65.7 – 73.0%
Pressure: 13.8 – 14.6 psi

This gets pretty technical, but it is important when talking about running concentrators at high altitude and isn't hard to understand:


There is volumetric flow and then there is mass flow. Volumetric flow shows how many liters passes through, no matter how dense or diffuse. The mass flow shows the flow of the actual mass based on what a liter of oxygen would have at sea level. Remember, at altitude, there is less atmospheric pressure and the molecules of gases will be further apart than at sea level, where the pressure of the atmosphere compresses them so that they are closer together.


The flow meter on concentrators shows volumetric flow, while my analyzer shows mass flow. At sea level, they are the same.

Here is an illustration: When a machine reads 10 LPM, 10 LPM of oxygen is produced, but the oxygen is not as dense at high altitude as it would be at sea level. If you are up here in Colorado and were to run the machine set at 10 LPM, the mass flow meter would show a different amount depending on your altitude - lets say 8 LPM for the sake of discussion. If you were to run it for one minute into a balloon and tie it off, that balloon would be be ten liters big. If you were to walk it down to sea level, it would shrink and that amount would be the amount that the mass flow meter would have read for it - that 8 LPM.

At near sea level, when the the concentrator is set at 10 LPM, the mass flow meter would also read 10 LPM and the balloon would still be ten liters big. If you were to walk it up to Colorado, it would expand and be bigger.

So, in the case of the two EX-15s that were tested near sea level, the volumetric flow shown on the concentrator should have been the same as the mass flow read on my analyzer. They were not. This could possibly be because the volumetric flow meters on the concentrators were altered by EO (in the same way UO does it).

The base unit for the UO and EO 8 LPM machines is a 5 LPM concentrator. In order to show a scale of 8 LPM, they had to put decals over the original flow meters. I also read on LE that they changed out the balls in the flow meters, as well.

Originally Posted by Mr. Smiley

If you're new to all of this, then gather as much information as you can before passing judgment. There are some personalities involved that have a history and you should consider the source of the information...

much love...

Yes, you should consider the source.

[kbinkster]

Originally Posted by Dennis Brady

I'm sure I, and the 100 or so pro artisans I regulary work with, could help and could provide excellent information. However, the operative term here is "subjective". To be universally valuable, test results must be objective. Kimberley has used every possible opportunity to denigrate Unlimited Oxygen. As a result, I would always be suspicious of any data she supplies and expect that data to be more subjective then objective. Until somebody steps up that doesn't have a dog in the fight, I'll rely exclusively on the information I get from my own tests and from independent unbiased users.

The M-15 and the two EX-15s that are included in my test results are owned with people without any dog in the fight. They are unbiased end-users.

I tested the M-15 with the owner at my side. The EX-15s were tested completely by their owner and results were sent to me.

Also, I had an opinion of Unlimited Oxygen long before I became involved in selling oxygen concentrators. I was an unbiased end-user at one time and posted my opinions back then. Selling concentrators has not made my opinion of them any worse.

[kbinkster]

Originally Posted by sarbeardog

Hi Patti,

Thanks for the info.

Here is the sum of what I read and understood.

If the flame is what I want and the concentrator gives me more oxygen when I ask for it, then its safe to assume that the concentrator is working the way that it should. I'm happy the concentrator is happy and my torch is happy!

the LPM and purity are basicly one and the same. LPM is the flow and the purity is the amount. The purity is not how clean the oxygen is coming out of the concentrator but the amount the concentrator is generating

Please correct me if I'm wrong in my summing up
thanks
Kathy

Hi Kathy, I know you did not address me, but I thought I ought to say something.

If the concentrator is doing what you want it to do and you are happy, that is great, but it does not mean that it is doing what it is supposed to be doing and someone else might use it and be unhappy with it.

LPM is the flow rate - the amount of oxygen put out by the machine - in this case, we are talking about how many liters of oxygen per minute. I've got an analogy/illustration. Substitute "oxygen concentrator" with a machine that takes salt water and turns it into fresh water and imagine filling one-liter soda bottles with the fresh water. At 8 LPM, that would mean that if you were to run the machine for one minute, you would fill up eight one-liter bottles with the water. Now, purity is how much of what is produced is actually fresh water, and not salt and other minerals. Say bottled water is 99% pure, but 90% pure water is still drinkable. But, at less than that, you start to have problems. At a little lower purity, it might not taste as good. At a lot lower purity, it can make you sick.

The purity is how "clean" the oxygen is coming out.

ETA:

I thought as long as I had an illustration going, I might as well put in how pressure plays into this.

Pressure, measured in psi (pounds per square inch) is the force at which the product is being delivered - the push behind it.

If you are just filling the bottles straight from the machine, then pressure would not matter. At 8 LPM, you would still be filling up 8 liters every minute. You would not be filling the bottles up any faster or more completely if the psi put out by the machine was 5 psi, 8 psi, or 15 psi. Now, if you had to connect a hose to the machine and fill up the bottles, then you would see that pressure makes a difference.

If the hose is twisted or kinked or tiny, then you are going to need a higher push (psi) to get the water through to the bottles. If the hose is straight and wide, then it doesn't take much push. If you start running more water and are using a big pipe instead of a hose, at some point, you will need a higher psi to push the water through and keep it moving along.

Torches act like the hoses. Some have more twists and turns and tiny tubes in them than others. For the ones that do not have so many restrictions, you can have lower psi and still be filling the same number of bottles per minute that you would at a higher psi.

[sarbeardog]

Originally Posted by kbinkster

Hi Kathy, I know you did not address me, but I thought I ought to say something.

If the concentrator is doing what you want it to do and you are happy, that is great, but it does not mean that it is doing what it is supposed to be doing and someone else might use it and be unhappy with it.

LPM is the flow rate - the amount of oxygen put out by the machine - in this case, we are talking about how many liters of oxygen per minute. I've got an analogy/illustration. Substitute "oxygen concentrator" with a machine that takes salt water and turns it into fresh water and imagine filling one-liter soda bottles with the fresh water. At 8 LPM, that would mean that if you were to run the machine for one minute, you would fill up eight one-liter bottles with the water. Now, purity is how much of what is produced is actually fresh water, and not salt and other minerals. Say bottled water is 99% pure, but 90% pure water is still drinkable. But, at less than that, you start to have problems. At a little lower purity, it might not taste as good. At a lot lower purity, it can make you sick.

The purity is how "clean" the oxygen is coming out.

ETA:

I thought as long as I had an illustration going, I might as well put in how pressure plays into this.

Pressure, measured in psi (pounds per square inch) is the force at which the product is being delivered - the push behind it.

If you are just filling the bottles straight from the machine, then pressure would not matter. At 8 LPM, you would still be filling up 8 liters every minute. You would not be filling the bottles up any faster or more completely if the psi put out by the machine was 5 psi, 8 psi, or 15 psi. Now, if you had to connect a hose to the machine and fill up the bottles, then you would see that pressure makes a difference.

If the hose is twisted or kinked or tiny, then you are going to need a higher push (psi) to get the water through to the bottles. If the hose is straight and wide, then it doesn't take much push. If you start running more water and are using a big pipe instead of a hose, at some point, you will need a higher psi to push the water through and keep it moving along.

Torches act like the hoses. Some have more twists and turns and tiny tubes in them than others. For the ones that do not have so many restrictions, you can have lower psi and still be filling the same number of bottles per minute that you would at a higher psi.

Thank you Kim and Pam for both of your responses. You did a great job Kim on explaining LPM and PSI.
I understood what purity of oxygen is but wasn't sure how that affected the torch. Kim, would you agree with Pam on the carbon build up with lower purity of oxygen? I always thought the build up of carbon was from propane but if the oxygen purity was lower then oxygen isn't burning as hot meaning the propane is doing its thing, making carbon.
Thank you again for taking the time to explain what is a simple concept but for me I was having some trouble with it.
Kathy

[Mr. Smiley]

Originally Posted by Blueflameart

I'm not the expert Kathy but from my findings purity and LPM's are not one in the same ... from what I've heard a 5lpm machine is putting out about 2.5psi give or take? So if you take my setup which is 2 - 5lpm machines with both set to 4 liters per the gauge I should be getting roughly 6-7 psi and around 92% purity. I've read that I should pump both machines up to 5 lpm, the max and get about 85% purity. The purity IS the amount of clean, pure oxygen your getting out of your unit. The PSI is just the amount of "push" your getting through the lines.

I'm sure Kim or Jack or maybe one of the others will jump in and give the correct numbers. I've seen just what it's like working on Invacare's, M-15's and now tanked and it's all night and day. If you've got nothing to compare to it's so hard to tell whats what ... but if you get a chance to work on all these unit's you would see it like night and day, both the good and the bad. Nothing will ever touch tanked oxygen but for the buck nothing will touch these concentrators either such a double edged sword. GL!

PSI is not doubled if you hook two together. The volume is doubled (LPM). If you only have 2.5 PSI with your machines, they are lower than any I've ever seen. You should get better than 85% purity out of any machine within it's high end limit.

Purity has nothing to do with PSI or LPM. It's the concentration of oxygen in the gas coming out of the concentrator. The higher the better, but 90% is usually adequate.

The UO units are tested before they leave the shop... to make sure purity, pressure and volume are what the specs for that model say they should be.

[kbinkster]

Hi Kathy.

Poor purity indirectly causes carboning. If you have poor purity, you usually have to run a smaller flame to get a clean, neutral flame that doesn't muck up the glass. That overheats the face of the torch and can cause carboning.

Running poor purity in and of itself is more problematic to what it does the glass than to the torch.

[kbinkster]

Originally Posted by Mr. Smiley

Purity has nothing to do with PSI or LPM. It's the concentration of oxygen in the gas coming out of the concentrator. The higher the better, but 90% is usually adequate.

Actually, LPM and psi do affect purity.

The lower the LPM, the higher the purity. The concentrator manufacturers chart it out and the LPM mark where purity starts to drop below 90% becomes the LPM rating for the machine.

If the purity hits 90% at 5 LPM, then the machine is rated a 5 LPM machine, even though you can make it produce more than that.

If you run more LPM than the machine is rated for,you will not only have lower purity, but you will damage the machine.

If a machine is rated at 8 LPM, then it should put out 90% or better at 8 LPM. If it does not produce 90% until it is dialed down to 5-6 LPM, then it is really should be called a 5-6 LPM machine.