Basic Vertecon 13cfm questions...

[CraigAClark]

FYI,

The 504 is also 100 CFM at 3000 psi

The model 504 is an economical, small, high pressure relief valve having excellent set pressure control over a large pressure range to 6000 PSI. It stays bubble tight to within a few PSI of set pressure and reseals bubble tight even after many vent cycles. Safety wire holes are provided for optional locking of set pressure adjustment.

SPECIFICATIONS

• Set pressure ----- adj. 300 to 6000 PSI
• Leakage bubble tight
• Max. fiow (air) --- 100 SCFM at 3000 PSI; 50 SCFM at 1500 PSI
• Equivalent orifice — .078 inch dia. gas or liquid
• Inlet ----- 1/4 male NPT
Outlet side vent
• Size 0.875" hex by 2.33" long
• Temperatures--------- -40F to 160F
• Materials bronze, anodized aluminum, & Viton

Looking at the drawing of the valve, it does not seem to be of the 'Pop" type, but I would check. I have one here, maybe I will take it apart and have a look, or just stick in on free port on my manifold to see how it behaves.

I have been working with breathing gas systems since 1988. In my experience, the 504 is not suitable for geko21's application. The manufacturer's specifications do not cover "in the field" problems. My advice is just that, to be taken or not as is.

---------- Post added March 27th, 2015 at 10:52 AM ----------

I am looking at it very intently right now... it doesn't seem to move

Just joking. Thanks, I got it and will see if a few more cycles will make a difference. If not, we will have to take something apart. What is the acceptable pressure for long term idle state of the filter chamber? What pressure is too low or is it just that it has to be kept above ambient? My understanding has always been that it just has to be above ambient, but I see that some poople seem to aim for high pressures.

The compressor manufacturer usually sets the PMV to create "dwell time" for gas in the filter tower. Bauer generally sets them around 1800 psi for 5000 psi operation. I'm not sure about their 6000 psi units, but I do know that Mako (Garner-Denver) sets at 2500 psi on 6000 psi systems. I would strive to keep the tower pressure at the PMV set point or above.

 

[ti325v]

I have been working with breathing gas systems since 1988. In my experience, the 504 is not suitable for geko21's application. The manufacturer's specifications do not cover "in the field" problems. My advice is just that, to be taken or not as is.

---------- Post added March 27th, 2015 at 10:52 AM ----------



The compressor manufacturer usually sets the PMV to create "dwell time" for gas in the filter tower. Bauer generally sets them around 1800 psi for 5000 psi operation. I'm not sure about their 6000 psi units, but I do know that Mako (Garner-Denver) sets at 2500 psi on 6000 psi systems. I would strive to keep the tower pressure at the PMV set point or above.

I agree that the 504 is not suitable, I was just providing additional information about it, I was clear in my post that I was not sure if it or the 1706 was a pop off valve or not, the 1706. looks like it may be, and I have one here that I may put on one of my systems to check.
That is all.

Agree with you about PMV set point, and I keep mine as high as seems reasonable, to extend the dwell time and squeeze more moisture out of the air in the final separators. M.S. is shockingly expensive here like $40 a pound, compressor oil is $30 a liter when I can get it.

 

[geko21]

Although that AE 211, PMV is not bubble tight, it shouldn't loose that kind of pressure over night, even taking in to consideration the lose of pressure when the tower cooled off to ambient. If there are no external leaks, I would look at the check valve between the final separator and filter tower.

Craig, after two days it is clear that our PMV is leaking pressure downstream to the manifold. In about 15 hours the pressure in the tower drops from 260 to about 140bar. This can somewhat be alleviated if I keep the manifold pressurized but I don't think that this is the best idea. Do you know of any fix for this particular valve? I guess that since it is brand new there wouldn't be much sense in ordering a replacement one, as it will probably do the same. Any ideas?

 

[swamp diver]

Craig, after two days it is clear that our PMV is leaking pressure downstream to the manifold. In about 15 hours the pressure in the tower drops from 260 to about 140bar. This can somewhat be alleviated if I keep the manifold pressurized but I don't think that this is the best idea. Do you know of any fix for this particular valve? I guess that since it is brand new there wouldn't be much sense in ordering a replacement one, as it will probably do the same. Any ideas?

That is a very common problem with those AE 211 priority valves due to the poppet and seat material choice (metal on metal). There is an old thread on here about someone calling the manufacturer AE and the owner saying that it is not expected to hold pressure for days and some leakage is to be expected.

Many have traded that AE 211 PV for the Lawrence Factor deluxe PV and had better results. I think if you look at the poppet and seat design on both you will see why.

Have a look at this thread.
http://www.scubaboard.com/forums/co...r-filter-media.html?highlight=deluxe+priority

LAWRENCE FACTOR®

---------- Post added March 30th, 2015 at 02:21 AM ----------

I have a question, do you folks know how most compressor manufacturers come up with the fill rate cfm of the block?

I don't know how the manufacturer does other than engineering design calculations but I just put a flow meter on the discharge and measure the FAD directly. You can purchase a flow meter for about a hundred bucks.

 

[Suzuki416]

If your fill manifold has four fill valves, you can simply just fill two tanks at a time while the other two are on standby. When two are full, close the valves and open the next two valves so that while these are filling, you can remove the full ones and attach the next two.

I would advise putting them in a water bath as at 13 cfm fill rate, they would get pretty hot in around ten minutes .

You should have a manual/auto override switch to bypass the auto pressure shutdown.

This is the easiest option to manage but requires having at least multiples of 2 cylinders to fill - what do you do if you need to fill 1 cylinder ?

Your whole setup is crying out for a bank.

 

[Namreg 58]

This is the easiest option to manage but requires having at least multiples of 2 cylinders to fill - what do you do if you need to fill 1 cylinder ?

Your whole setup is crying out for a bank.

Ummmm........only open one valve????

Speaking from experience, when filling many cylinders, I find it easier to fill direct from the compressor and switch the "spill" to the banks to give me time to hook up the next lot of tanks in order to avoid having to turn the compressor off. When the next lot are hooked up I switch back to the fill panel again and repeat the process.

Banks are handy if you need a few fast fills or top ups for multiple diving days. However to get the most volumetric efficiency out of a 4 bank system, one needs to use one bottle at a time and start with the scuba tank with the highest pressure first and fill till the pressures equalize, then shut that tank down and open the next highest tank till pressures equalize and repeat the process till there is no pressure gain. Then you close the first bank and open the second bank and start the process again with the tanks that have not been filled to capacity yet. As you can see, this is a drawn out process and time inefficient to boot and will only fill around 12 tanks depending on their size and residual pressures.

Far easier to hook up 4 tanks, let them equalize and fill direct from the compressor.

 

[Suzuki416]

Ummmm........only open one valve????

So buy not having a bank the OP must stop / start his compressor (& run it also at times that are more inconvienant than others)... This seems dumb to me.

Speaking from experience, when filling many cylinders, I find it easier to fill direct from the compressor and switch the "spill" to the banks to give me time to hook up the next lot of tanks in order to avoid having to turn the compressor off. When the next lot are hooked up I switch back to the fill panel again and repeat the process.

Because you use the bank to avoid stop starting.... If you had enough capacity in the bank you may even get away without running the compressor....! - at that time....

Banks are handy if you need a few fast fills or top ups for multiple diving days. However to get the most volumetric efficiency out of a 4 bank system, one needs to use one bottle at a time and start with the scuba tank with the highest pressure first and fill till the pressures equalize, then shut that tank down and open the next highest tank till pressures equalize and repeat the process till there is no pressure gain. Then you close the first bank and open the second bank and start the process again with the tanks that have not been filled to capacity yet. As you can see, this is a drawn out process and time inefficient to boot and will only fill around 12 tanks depending on their size and residual pressures.

Far easier to hook up 4 tanks, let them equalize and fill direct from the compressor.

Get a bigger bank.