Help in finding a great priority valve/back pressure valve to use on storage vessels

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T

txgp17

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Hello All,

I'm career firefighter looking to solve a problem with our breathing air storage system.

I'm looking for a priority valve/back pressure valve that is really reliable, high quality, and can be adjusted to at least 5,500 psi. I'm looking to create a priority filling circuit for our storage vessels, and our SCBA's store air at 5,500 psi, so I need a valve that can go over that.

I first looked at Aqua Environment 211, as that's what's on the outlet of most of our compressors already, but you can't adjust it beyond 5,000 psi.

Then I stumbled upon the Lawrence Factor Priority Valve #VL-530141-TG, but it can only be adjusted to 5,000 psi. (specs here)

Then I found the Aqua Environment 635, which can be adjusted to 6,000 psi.

If anyone else knows of another choice out there, or you have experience with any of these products, please let me know. Thanx in advance!
 
iain/hsm:
Don't wast your time with either the Aqua Environment or the Lawrence Factor BPR
If you require high quality, reliable certified industrial components then look at the Tescom range.

Tescom series 54-2700

http://www.documentation.emersonprocess.com/groups/public/documents/data_sheets/d54271905x012.pdf

Tescom series 26-1700

http://www.documentation.emersonprocess.com/groups/public/documents/data_sheets/d26170543x012.pdf
Click to expand...
Thanx for that. I was reviewing the 54-2700, and it lists the maximum pressure as 5,500. I need a valve that can handle 6,000 and can be adjust to hold at least 5,800 psi in priority.

Was I reading the specs wrong?
 
txgp17:
Thanx for that. I was reviewing the 54-2700, and it lists the maximum pressure as 5,500. I need a valve that can handle 6,000 and can be adjust to hold at least 5,800 psi in priority.

Was I reading the specs wrong?
Click to expand...

Not being absolutely sure your application I gave two, the 54 series for handling bulk gas transfer ( large volume at large Cv capacity) and the 26 series for filling small cylinders (small volume and slow filling) without need to turn each bank cylinder on and off in order to decant up the pressures

Using the 54-2700 at 6K just call the Tescom engineers they will put you right on the seat material ( assuming its breathing Air) Glass filled Peek and Viton would be OK.
But your close to maxing out the spring rate at 6K. and I am not sure the spring lock pressure, again speak with Tescom as you are very close.

Consider also the 26 series option I included. The Cv rating needs consideration also in relation to the slow filling requirements of fibre wrap cylinders, especially if a varying amount of cylinders are to be filled at one time, you may need also to address the charging rates.

A small 1/4 MxF stainless orifice is an option (cant remember the orifice size but around 20 thou) would be useful for fibre wraps but take care at the design stage not to fill a single tank off a manifold block if it is rated for the multiple cylinders.

Orifice also needs consideration if or when filling from empty, as it takes too long and the pressure drop too large if you use a frit as opposed to an orifice to reduce flow rate.

In fairness there is nothing wrong with the LF or AE units they are fine for dive shops and the like its just they are not certified for professional applications requiring CoC's, 3rd party approvals, material certs, etc

For others: the OP application (I am assuming) is filling a small firefighters bottle using a priority filling method from a number of HP storage cylinder in a bank at various pressures without having to first manually select the lowest storage cylinder pressure first.

AE have a helpful diagram that explains the process better than I can enclosed below.

http://www.aquaenvironmentinc.com/p... 1018 to Priority Fill from Cascade Banks.pdf
 
iain/hsm:
Not being absolutely sure your application
Click to expand...
Thanks again for the input.

Our system is 6,000 psi filling 8 ASME pressure vessels (491 cu-ft @ 6,000) using a Bauer 25 cu-ft/min rated compressor.

Our carbon-wrapped SCBA cylinders hold 66 cu-ft of air at 5,500 psi. The low pressure alarm goes off at 1,375, so we're typically filling them from that point back to 5,500. We have two fill stations that each fill two bottles at once (four total).

The cylinder manufacturer recommends a fill rate of 1,500 psi per minute, which translates to about a 4 minute fill time.

The dilemma we have is that the present circuit for refilling the banks just puts them on a common line with check valves, and the new air simply follows the path of least resistant, which is always to the lowest bank. After just a few fills the pressure of our highest storage bank drops below our fill pressure, while the pressure in the lowest bank steadily rises. Then the only way to make a complete fill is directly off the compressor, which requires a longer wait time, and slows down the process of filling.

Using priority valves would force all of the air from the compressor into the final bank, ensuring we can make a complete fill once the cascade system has brought the cylinder close the it's fill pressure.

I'll give the guys at TESCOM a call, but they're in Minnesota so I'll have to wait until they open.

The VP of Lawrence Factor called me personnel to inquire about my needs, and when I explained he directed his personnel to test the LF valve at 5,700. After the test he e-mailed me to say it performed as desired and assured me it would work in my application.
 
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