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Demand Valve


mitch brown
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Here's is one...

If you are using a welding regulator, more than likely you have an unlimited flow rate available to you, so you'd not benefit from a demand valve's increased flow. 

Here is a post I made a while back explaining things:

Quote

I have a demand valve, several 25 lpm regs and a 40 lpm reg. My advice is always this...if you have a proper mask like the ones we all recommend here and you can't "outrun" a 25 lpm reg with your effective breathing technique, a demand valve won't help your abort times. Now....what do I mean by "outrun". If you are constantly having to wait for the bag to fill you are outrunning the flow. If there is very little or no wait then you have enough flow for your technique and more flow won't be of use to you.

Now....for the sake of discussion you are outrunning your 25 lpm reg and would benefit from a higher flow rate there are several ways to get it. One is the garbage bag rig which some use but personally I don't care for. Another is the fabled demand valve or just a plain old reg with a flow rate higher than 25. As I stated above I have both. Each has benefits and drawbacks. My demand valve sits beside my bed at the ready for those night time wake up calls. It's easy to reach over, turn the tank on and start huffing. No thought to flow rates, fumbling with dials just grab it and go. To me this is where a demand valve shines. It's good in a car for the same reasons. It does conserve O2 because it gives you no more than you ask for. Drawbacks.....cost. They can be pricey. If money isn't too much of an issue, you believe the flow rate will be of benefit and you like what I've laid out here, go for it. 

But before you do, consider this..... A 40 lpm reg can be had for much less than a new demand valve. It will give most people all the O2 they can handle so abort times will be very close if not the same. Yes it does require more thought to dial in and you'll probably be adjusting it up and down more than a 25 but having that extra flow when you need it is great. If dollars are tight, consider this route.

If I were sitting on the couch watching TV and needed O2, I wouldn't step over one to get to the other....but for the reasons listed above each makes sense in their own way.

I hope this helps a little. 

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I can see why you'd be incentivized to go for a demand valve for this aspect you mentioned:

21 hours ago, mitch brown said:

demand valve saves 02

And that @Racer1_NC mentioned:

10 hours ago, Racer1_NC said:

It does conserve O2

Anyone who has been caught on a weekend, holiday or whatever having run out of O2 because they went into sudden unexpected high cycle and burned through tanks faster than anticipated might agree with me that there can be a priceless component to avoiding such a situation.

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I’m looking to conserve 02. My welding tank is an ALBEE TANK which are like bbq tanks at my supplier when empty I just take the old one in and swap out for a full one. They have a built in regulator with an on off switch and a flow rate dial which goes up to 45lpm so when I’m doing my breathing technique which is hyperventilate to expel all existing air in my lungs then one big breath in and hold for 30 seconds I gotta turn off the dials which is a pain cause it usually take 3to 4 times like this to abort. So ya it’s to save 02 and get rid of all the fumbling around. So does anyone have info on where to buy and how the work?AF6FCB90-5A39-45EE-916E-476E97C5F857.thumb.jpeg.46d0495a58afa513496b73025c472d6d.jpeg

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I'm gonna wonder whether maybe that built-in regulator might not take a DV.  Verging into territory I don't know very well, it's my understanding that a DV requires a particular kind of valve on the regulator (a DISS valve).  You would want to be sure you have that.  Since a couple of clicks on your photo gives a very close-up view of the tank, maybe @Racer1_NC, or @xxx, or someone else can tell whether you have it.

I was composing a brief discussion of how much O2 a DV actually saves, but in your case I can see that avoiding the fumbling and the waste would be great.  Is this the only kind of "industrial" O2 tank you can get in Canada, or just what you wound up with?  In the US, tanks can be obtained without a regulator and then you use your own.

15 minutes ago, mitch brown said:

So does anyone have info on where to buy

No idea about Canada, but generally in the US you need a prescription to get a DV.  Sometimes they are sold on eBay.  There seem to be some there now (type oxygen demand valve into the eBay search bar).  There have been some people here who have described other ways to get them (type demand valve into the search bar at the top of any page at this site and you'll see them, and you'll also see a lot of potentially useful discussion about DVs).  

As you'll see, they're not inexpensive, and so part of the question for me has been whether if just conserving O2 is the goal, what's the cost of any "wasted" O2 vs the cost of the DV (and, potentially, the cost of a reg with a DISS valve).  The savings from conserved O2 might not be as much in most cases (not necessarily yours) as buying and another big tank and refilling it a few times.  

Any chance that you could set the reg low enough that the bag fills slowly (but fast enough) while you're hyperventilating that you don't have to do the on/off switch?   Or maybe xxx's "redneck bag" would be a reasonable solution for you in some circumstances?? https://clusterbusters.org/forums/topic/4919-batchs-hyperventilation-red-neck-bag/

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Thx CHF just don’t want to fumble with knobs when in crisis mode. And saving 02 means less trips to the depot. Also I have 3 tanks and having built in valves makes it easier and less chance of forgetting valves and literally no set up times etc. Here in Canada I just pay for the tanks 45$. I’ll keep looking and god bless you for all your hard work and knowledge 

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A small PS.  I remember seeing a video about O2 use in which the guy was saying that the way that the Optimask/ClusterO2 Kit is built, when using high flows some O2 tends to leak from the back of the tube that the mask is attached to. As I remember it, he put his palm over that end of the tube while using it. That video is pretty old now, so it could be that that minor flaw has now been corrected.  

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