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CO2 Controller Needle Valves and Solenoids

Contents:

  1. Cheap Solenoid valve for CO2?
    by gb-at-dixie.cs.unc.edu (Gary Bishop) (8 Sep 93)
  2. CO2 regulators and solenoids ?
    by poulter-at-access1.digex.net (Harry D. Poulter) (1 Mar 1994)
  3. Solenoid valves--Where to find????
    by sanford1-at-ix.netcom.com (gary sanford) (28 Feb 1995)
  4. CO2 w/o regulator
    by "Jamil Zainasheff" <jamil_zainasheff-at-internet.uscs.com> (12 Jun 1995)
  5. CO2 Needle Valves
    by steveb-at-bga.com (Steve Benz) (Wed, 8 May 1996)
  6. Teflon tape
    by huntley-at-ix.netcom.com (Wright Huntley ) (Thu, 9 May 1996)
  7. Nupro valve
    by Jeff & Denise Dietsch <dietsch/voicenet.com> (Wed, 10 Sep 1997)
  8. [Fwd: flow valves]
    by Marque Crozman <mcrozman/eng.uts.edu.au> (Sat, 30 Aug 1997)
  9. Hoke valves
    by Justin David Collins <n9720235/cc.wwu.edu> (Wed, 3 Feb 1999)
  10. Adjustment of Nupro Valves
    by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com> (Mon, 1 Feb 1999)
  11. Nupro "S" Valve
    by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com> (Sat, 26 Dec 1998)
  12. ARO F01 needle Valves
    by Pat Bowerman <bowerman/specent.com> (Wed, 31 Dec 1969)
  13. Cv and flow
    by Dave Gomberg <gomberg/wcf.com> (Thu, 23 Sep 1999)
  14. More CO2 Injection Stuff
    by "Dan Dixon" <dandixon/home.com> (Thu, 23 Sep 1999)
  15. Cv and flow
    by Erik Olson <erik/thekrib.com> (Fri, 24 Sep 1999)
  16. CO2 levels dangerous yet?" and other questions
    by erdoz1 <erdoz1/wt.net> (Mon, 27 Sep 1999)
  17. More CO2 Injection Stuff
    by erdoz1 <erdoz1/wt.net> (Wed, 22 Sep 1999)
  18. More CO2 Injection Stuff
    by "Peter G. Aitken" <peter/pgacon.com> (Thu, 23 Sep 1999)
  19. Needle valves
    by Zxcvbob <zxcvbob/tcw.net> (Thu, 23 Mar 2000)
  20. CO2 Flow control
    by Scott Hieber <shiebernet/netscape.net> ( 3 Mar 00)
  21. Swagelok/Nupro metering valve site
    by Scott Hieber <shiebernet/netscape.net> (15 Mar 00)
  22. Source for CO2 System Fittings -- Source for Tube & Fittings
    by Scott Hieber <shiebernet/netscape.net> (24 Feb 00)
  23. ARO needle valves
    by Larry and Lynn Fecich <bit64/isrv.com> (Thu, 18 Jan 2001)
  24. Cv and valves
    by George Booth <booth/lvld.agilent.com> (Thu, 14 Sep 2000)
  25. HOKE valves
    by "James Purchase" <jpurch/interlog.com> (Wed, 13 Sep 2000)
  26. Aquatic Plants Digest V4 #756
    by "Mortimer Snerd" <mortimersnerd/uswest.net> (Mon, 1 Jan 2001)
  27. Needle valves in CO2 systems poll
    by "Jamie Johnson" <jjohnson/davisfloyd.com> (Wed, 3 Jan 2001)
  28. Needle valves in CO2 systems
    by "David Ozenne" <dozenne/10fold.com> (Fri, 05 Jan 2001)
  29. CO2 valves & 24v transformers
    by Tom Petersen <peter334/tc.umn.edu> (Sun, 15 Feb 1998)
  30. More CO2 Injection Stuff
    by "Dan Dixon" <dandixon/home.com> (Thu, 23 Sep 1999)
  31. CO2 and Needle Valves
    by "Ken Guin" <kenguin/homemail.com> (Wed, 22 Mar 2000)
  32. Clippard Minimatics for CO2 fittings
    by Lobos <lobos0331/yahoo.com> (Thu, 15 Nov 2001)
  33. CO2 -- High Pressure/Low Pressure
    by "Dixon, Steven T. (BEn)" <stdixon/ben.bechtel.com> (Wed, 20 Sep 2000)
  34. Metering Valves - CO2
    by Bruno Fernandes <SurfnTurf/hybrid8.com> (Fri, 15 Sep 2000)

Cheap Solenoid valve for CO2?

by gb-at-dixie.cs.unc.edu (Gary Bishop)
Date: 8 Sep 93

Eric Vaitl asked about solenoid and needle valves for CO2.  Here are
the relevant sections from my previous postings about my homebrew CO2
system and controller.  I listed the place I bought them in the
Raleigh, NC area and also the section of the yellow pages in which I
found the advertisement.  You probably have a distributor in your area.
gb

-----------------------------------------
Solenoid Valve: $24.00 from "Air Power Inc." (In Yellow Pages under
Valves).  This is solenoid valve model "CAT33P-012D" from "The ARO
Corporation, One ARO Center, Bryan, OHIO 43506, Phone (419)636-4242".
You can get it with a variety of coil voltages.  I chose 12 volts DC.

Needle Valve: $9.60 from "Air Power Inc." (In Yellow Pages under
Valves).  This valve is the model "NO1" from "The ARO Corporation, One
ARO Center, Bryan, OHIO 43506, Phone (419)636-4242".  It provides
infinite control from full-close to full-open.  It has a neat color
scale to indicate the degree of openness and can be locked at any
setting.  The adjustment is very smooth; I can go from off through
incredibly slow flows to just right and beyond to way more than I
need.  I have not used the $42 Nupro S-series valve that some of my
friends on the internet are using but if it is better than this one,
it may well be over kill.  You can locate a distributor of this valve
in your area by calling the ARO company.  Even if you can not locate
this exact valve, your local dealer might be able to suggest an
equivalent substitute of a different brand.

CO2 regulators and solenoids ?

by poulter-at-access1.digex.net (Harry D. Poulter)
Date: 1 Mar 1994

In article <GB.94Feb21091335-at-dixie.cs.unc.edu>,
Gary Bishop <gb-at-dixie.cs.unc.edu> wrote:
>George is correct.  $175 is serious bull.  Here is the account of my
>setup..
>gb

(material excised)

For real savings, try surplus.  American Science and Surplus has 110V 
solenoid valves with threaded 1/4" ID connections for $3.25 in 
"apparently new" condition - Jan 94 catalog, item #21785.  They also have in 
general the most enjoyable catalog around.  (Hey, I'm just a happy customer).
Their no. is 708-982-0870

Another good source for surplus industrial-type equipment is
Herbach and Rademan 215-788-5583 (I have an old catalog, so this might 
not be right) 


Solenoid valves--Where to find????

by sanford1-at-ix.netcom.com (gary sanford)
Date: 28 Feb 1995
Newsgroup: alt.aquaria,rec.aquaria,sci.aquaria

In <3ito3n$hhh-at-hplvec.lvld.hp.com> booth-at-lvld.hp.com (George Booth) 
writes: 

>
>gary sanford (sanford1-at-ix.netcom.com) wrote:
>> Also try U.S. Plastics. It's in the reef FAQ.
>> GReat catalog,-at- 1 800 537 9724
>> Page 27 all plastic solenoid valves,$200-315!
>
>HeelllooOOOooo.  The original poster is trying to find *CO2* solenoid
>valves at less than than the $60-90 aquarium suppliers sell them for. 
>I don't think a $200 plastic water valve is going to help.  
>
>-----------------------------------------------------------------------
------
>George Booth                         "Nothing in the world is more 
dangerous 
>booth-at-hplvec.lvld.hp.com             than sincere ignorance and 
conscientious 
>Freshwater Plant Tank Technology     stupidity" - Martin Luther King, 
Jr. 
>-----------------------------------------------------------------------
------
>

Page 25 ..catalog #22197 or 8 "up to 125 PSI ..$26.98
OK!


CO2 w/o regulator

by "Jamil Zainasheff" <jamil_zainasheff-at-internet.uscs.com>
Date: 12 Jun 1995

I got tired of mixing yeast cocktails and broke down and bought a 20#
CO2 tank and a Uniweld regulator.  In searching for needlevalves I came 
across one made by Parker.  The thing is rated to 5000 psi
and has a large/heavy brass body which works well for kinetic 
transfer.  So, being the curious sort that I am, I tried it on the tank with 
and without a Uniweld regulator.  The resultant flow is steadier from 
the needlevalve WITHOUT the regulator.  Tank pressure is much more 
stable than any of the $55 regulators at a low (25 psi) pressure.  Since 
the flow I use is minimal the heavy brass body keeps the valve from 
iceing up (doesn't even get cold).  The Parker needlevalve has a very 
fine adjustment to it and can deliver any flow from "zero" to "empty 
your tank in an hour".  Best of all it was only $17.  Anyone interested 
in a slightly used Uniweld regulator? :)


CO2 Needle Valves

by steveb-at-bga.com (Steve Benz)
Date: Wed, 8 May 1996

Stephen Pushak <Stephen.Pushak-at-saudan.HAC.COM> writes:
>I've got the CO2 bottle, I've got a good regulator. Now I need to
>find a reasonably priced needle valve.
>I haven't been able to find the ARO model N01 which is mentioned in the
>FAQ.

I recently got my needle valve, regulator, et. al. via the advice in the
FAQ.

First off, I can't understand why you can't find this valve?  Could they
not tell you a [remotely] close distributor, or what?  Could it be that
you just called on a day when they weren't there?  [[They are on CST, BTW]]

But assuming you get that taken care of, there's some other stuff you
ought to know that, unfortunately, is not included in the FAQ.  I've
been planning on adding an addendum to that part of the FAQ, and, although
my saga is not yet complete, I can offer up this much of it (which doesn't
include my attempts at automated CO2.)


Life After You Get Your Needle Valve
- ------------------------------------

  Trouble is, the fittings on the regulator don't just screw right into
the needle valve.  Usually (I think), regulators come with an output
adapter for welding equipment.  The output threads of that only work
with odd bits of welding equipment.  The needle valve and also the
solenoid, if you go that far, are threaded for 1/8" NPT -- NPT stands
for National Pipe Thread, which is a US standard for pipe threading.
So your first obstacle is to adapt the regulator to the needle valve.
My regulator, like most others, I think, has this adapter for welding
equipment, but if you take that guy off, you get 1/4" NPT.  It was no
small effort to get this adapter off, but I did it with a big honkin'
wrench, a vice, and much elbow grease.  It's absolutely crucial that
you ask the guy you buy the regulator from how the regulator can be
adapted to "NPT" piping - it's probably going to be a deal like mine,
but you need to be sure so that you don't do something you can't undo.

  Now, assuming you've got the NPT output from your regulator, you need
to get yourself an adapter.  In my case, the adapter is a "1/4inch to
1/8inch male-to-male NPT adapter."  Not to daunt anybody, but aquiring
such an adapter can be about as hard as getting the needle valve.
But if the local supplier for the needle valve doesn't have these
doo-dads, they probably know who does.  (In my case I got the needle
valves from a company called "Bearings, Inc.", and the adapters (yes,
the plural is, sadly, correct), from "River City Air & Hydraulic".)

  Assuming you get your regulator connected to your needle valve, your
next step is to get your needle valve connected to your plastic-air-line-
tubing.  This is simple if you know the code words: "Hose-Barb".
You'll want a '1/8" NPT hose-barb adapter.'

  A word about connections:  First, don't use "Teflon Tape" for CO2
connections.  My welding supplier says the best thing to do is just
screw everything together real tight.  And he means "real tight" too.
>From what I can see, his definition of "real tight" is to get it as
tight as you think you can get it, and then give it another turn.
[[ This is a good occasion to visit your ex-marine neighbor... ]]

  A word about pricing:  happily, these adapters are cheap.  My bill
for the 1/4"-1/8" adapter, the hose-barb, and an 1/8"-1/8" adapter
to connect up my solenoid, came to US$5.02.

  Now, if you go for the solenoid, there's more to the story, but I haven't
figured that part of the story out completely so you'll have to wait
for the paperback, as it were :-]

  And by the way, Gary Bishop mentioned to me that there exist such things
as "air-gap" Ph probes and "Amplified" Ph probes.  Does anybody know where
stuff like this can be found or more about what it is about?

                                        - Steve
- ------
Steve Benz (steveb-at-realtime.net)   |   Pragma Systems, Inc.
Author of ZipPiz, a Windows utility for unpacking downloaded archives.
http://www.ccsi.com/~pragma/zippiz.html | ftp://ftp.ccsi.com/pub/pragma


Teflon tape

by huntley-at-ix.netcom.com (Wright Huntley )
Date: Thu, 9 May 1996

Hi all,

The prime value of teflon tape is with liquids. *Nothing* liquid seems 
to wet it, so even horribly sloppy joints don't leak, anyway. It is 
also a fair lubricant in the threads. Nice stuff.

Unfortunately, only impeccable technique will prevent small shreds of 
it from getting into pneumatic systems and causing the most damage at 
the worst possible time. This is why it is forbidden in almost any 
industrial application involving gasses (as opposed to liquids). A 
little plumber's goop does exactly the same job, without hairy shreds 
to block needle valves, etc.

Wright

Just back from the Moapa Preserve and Ash Meadows, where we did habitat 
maintenance and helped do population surveys on Crenichthys. HOT! 
Collected some beautiful Val and pennywort, too!


Nupro valve

by Jeff & Denise Dietsch <dietsch/voicenet.com>
Date: Wed, 10 Sep 1997

Not to reiterate, but I will a bit:)
I have the Nupro S series metering valve and it works great.  It is not
designed as a shut off valve, but will stop the flow of such low back
pressures.  I have operated it at a pressure as high as 65psi and no
problems.  Although I should note, I am currently running at about 15psi.
As someone else mentioned(George?) the flow stops before my valve is
seated, so I would guess you have another problem.  
1)  First thing I would check is Eric's idea with the knob.  The easiest
possible solution.
2) Another easy mistake is, check to make sure you connected it correctly.
Most meddle valves have a designed flow direction.  Some of my nupro valves
have a arrow on them indicating this.
3) Since needle valves are capable of such low flow rates, their parts are
small and therefore fragile.  If a needle valve is shut down to tight it is
possible to damage the needle itself or the seat.  I do belive these valves
can be disassembled to check for damage.  
4) There is always the possibility that the particular valve you have may
be damaged or since there is not labeling on them, the wrong one.
5) Debris can also be a problem.  Teflon tape is a common culprit.  Again
with such fine offices in needle valves a small piece of debris could hold
the valve open just enough to offer you the headaches you're experiencing.  
   I will have to say that this valve is a good choice, and that it will
work, check out all the offered information and make sure it is not a
mistake or defect.  

Good luck,
Jeff


[Fwd: flow valves]

by Marque Crozman <mcrozman/eng.uts.edu.au>
Date: Sat, 30 Aug 1997

This is a multi-part message in MIME format.
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Greetings George,

    Just thought I'd drop you a note to add to the info on
CO2 needle valves for your site and possibly the Krib.

More information on the Nupro valves. They are made by a US
company called Nupro, whose parent company is Swagelock, who make a
lot of pressure valves, connectors and hosing. (you can virtually buy
all
gas fittings from them for your CO2 system at a price less of that of
Dupla)

The Nupro valve you have listed is not the smallest  one they have
available.
The one you have listed, they quote as being their "M series" valve and
have a
max Cv rating of 0.03. This rating is like the equivalent of resistance.
Which,
according to their data sheet, translates to a flow rate of 1.2 cubic
feet per
minute when connected to an inlet pressure of 2 bar (35psig).

The linearity of the valve is also pretty linear, with a slight kink at
the bottom end,
approx 5% off being linear (kink only lasts for the length of the first
turn). The
valve has a total number of turns to open of 8-10.

The reason for the variation, is because this depends on the minimum
open setting.
The valve, which by the way is not refered to as a needle valve, but
rather as a
metering valve, so I suggest that when people go to by a valve from a
valve and
fitting company, they might have better luck finding the right sort of
valve by asking
for a metering valve.

These type of valves are not designed as shutoff valves, so some sort of
shutoff
valve should be included, if you want to switch off the flow. (Although
this could
be done by winding down the regulator) What I have done is installed my
solenoid
valve before it, so use that to shut it off. This also has a manual
override, so that you
don't have to power up the solenoid if you don't want to.

They do have a smaller valve, which is listed as being the "S series".
This has a max
Cv rating of 0.004, which at the same inlet pressure of 2 bar (35psig),
translates to
a maximum flow rate of 0.15 cubic feet per minute. This valve has a
number of turns
till open of 8-12. It also has a larger kink (as expected) at the lower
end, but becomes
almost completely linear from the third turn onwards.

There is also an "L series" that is bigger again than the "M series"
with a max Cv of 0.15

The only difference in the labeling between the one you list and the
smaller one, is that
you replace the M, with an S.

The M and S series valves come in both 1/8" and 1/4" fitting sizes and
are available
in 316 stainless steel, brass (cheapest and suitable for CO2), and alloy
400.
They can withstand pressures up to 2000psig or (137 bar), are panel
mountable
and have three options of handles, vernier (mmmmm), fine adjustment and
slotted.

The handle has two allen key slots, one is used for setting the minimum
flow, and the
other is to lock the handle at a particular setting, useful if there is
the possibility of
it getting bumped, or affected by children etc.


The version I bought is labelled as B-SS4 (The B stands for brass and
the 4 stands
for 1/4") The 1/8" version is labelled as B-SS2.

The valve comes standard with  fine adjustment handle, but the vernier
to go with
it, adds a -VH to the labelling, so the one I bought is then labelled
B-SS4-VH.

The version you refer to is labeled B-4MG, which is a 1/4" fitting
version of the
"M series", a 1/8" version of the same is labelled B-2MG.

Again, adding a -VH turns it into the vernier version.

The valve is fantastic, allowing me total extremely fine control over my
CO2 flow
rate. I can wind the rate from about 1 bubble every 5 minutes, to about
4-5 bubbles
a second, linearly, if the inlet pressure remains constant.

Changing the inlet pressure allows me a greater control range.

In Australia, I bought the valve from

Brisbane valve and fitting pty ltd,
60 commercial road,
Newstead,
Queensland.
Tel: 07 3252 8900

and it cost me AU$77.25 for the valve (B-SS4), and AU$29.75 for the
vernier.
(Ex tax)

 Kindest regards,

Marque Crozman.


Hoke valves

by Justin David Collins <n9720235/cc.wwu.edu>
Date: Wed, 3 Feb 1999

In response to Dave Gonberg's comments on low pressure CO2 systems:

I have one of the Hoke valves you mentioned, and love it.  I find the
quality and control it gives me much better than my girlfriend's Nupro.
However, they don't cost $100.  I got mine at an industrial valve supplier
in Bellingham, WA, for $40.  Also, I was told they were made on the east
cost, not england.  It may have been that they are imported into the US
via over there.  If anyone want more info on these, feel free to contact
me.

Justin Collins


Adjustment of Nupro Valves

by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com>
Date: Mon, 1 Feb 1999

Carl and Lisa wrote about having problems adjusting their Nupro S valve.
"Setup was a little more difficult this time.  Based on what we read, we
started by setting the regulator to 30#.  We then tried to use the Nupro
valve to adjust the bubble count.  Perhaps it was our expectations, but
we were not  able to get the "precise" control we thought we should
have."

I remember having the same problem a couple of years ago when I first
set up my Nupro valve.  Erik Olson helped me out at the time and
hopefully will jump in if I get this wrong.  There is a set screw on the
Nupro (on the twist knob, I think) that is preset at the factory to stop
the valve before it completely shuts off the gas.  I think the idea is
that this protects the valve against damage from overtightening on shut
off, while leaving all but the hapless aquarist with enough control over
the flow rate.

To solve the problem loosen this set screw with a small hex wrench and
raise the twist knob a little bit higher on the valve stem to allow for
shut off of gas.  I don't think this will damage the valve at the
pressures we use in a CO2 setup.  (Remember that these valves are
designed for very high pressures.)  However, don't overtighten the valve
to shut off the gas.  the In any event I have been able to gain good
control over flow rates since making this adjustment on the valve stem
and the valve has worked perfectly since I installed it.  I think this
is Erik's experience as well.

Good luck.  I hope I'm remembering this correctly.  I look at my valve
this evening and report back if I've misstated the situation.  Regards,
Steve Dixon   San Francisco


Nupro "S" Valve

by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com>
Date: Sat, 26 Dec 1998

Andy wrote:  >>> Does anyone know what pressure a Nupro Series 'S' valve
should be run at ?>>>
I only have the "M" series Nupro valve.  The information sheet which
came with the valve stated that the valve could handle a very wide range
of pressures, including up to 2,500 psi, if memory serves.   So check
the material that came with the valve.  It should say.  If not, I
wouldn't hesitate to experiment in the range of say, 20 to 100 psi.  I
suspect the "S" series can take a ton of pressure < no <G> intended>
without difficulty.  The output pressure meter for my Victor CO2
regulator reads from zero to 200 psi.  I couldn't follow the terminology
of your original post, but I see a second set of units on the meter.
200 psi appears to correspond to 1400 kPa (whatever that is).  The
relationship between psi and kPa appears to be linear.  100 psi = 700
kPa.
Good luck,  Steve Dixon in San Francisco


ARO F01 needle Valves

by Pat Bowerman <bowerman/specent.com>
Date: Wed, 31 Dec 1969

> From: Ken Whelan <ken@paceindustries.com>
> Subject: Needle Valves
>
> I'm using the ARO F01 needle Valves bought from Graingers as specified on
> George Booth's web page.   The problem I am having with these valves is that
> they do not turn all the way off.  One of them will turn far enough down to
> be acceptable,   The other will not get that far down and I am having to
> bleed off the excess CO2 in order not to overdose the tank.   This is a
> problem since I am wasting CO2 and I can't seem to get it adjusted very
> well.
>

Ken, I have had a similar problem with that valve. A friend of mine also had the same problem, so he called Grainger
and inquired about it. After several more phone calls, he was finally advised to crank up the input pressure to 100 psi.
I tried this on mine, and it seemed to help. It still won't shut completely off, but now I don't have a problem getting it down to 1 bubble per second. FWIW, I also have the NuPro valve. It _will_ shut completely off, but it seems even more sensitive to temperature fluctuations than the ARO. Perhaps that is because it is completely
made out of metal compared to the ARO's "thermoplastic".

Hope this helps,
Pat Bowerman

PS: Did I see Moontanman post a real name the other day?


Cv and flow

by Dave Gomberg <gomberg/wcf.com>
Date: Thu, 23 Sep 1999

At 03:48 PM 9/23/1999 -0400, Peter G. Aitken asked:
>I have been looking into the Swagelock needle valves. The "S series metering
>valves" is indeed the lowest flow rate valve style they make. The maximum Cv
>is 0.004 (valve fully open) but according to the flow data graph I have you
>can get a Cv as low as 0.00025 with the valve open 2 of its 10 turns. I
>think this will be fine for a low pressure system - if not someone please
>enlighten me before I order one! 

Erik, please add this to the appropriate place on the Krib:

For gases:

CFM=22.7*Cv*sqrt((delP*P1)/(460+T)(SG))

where delP=P1-P2
P1= input pressure (psi)
P2=output pressure
SG=specific gravity of the gas relative to air=1.0
T=temperature (F)

If you are trying to use a valve to drop regulator output from a stable
10psi to the 1psi you need at the bottom of a two foot deep tank to make a
bubble, and the gas is CO2 and the temperature is 75F, this means:

CFM=7.2*Cv; Cv=CFM/7.2

If we want 1 L (about a quart) per day, that is about 1/40700 CFM.

Cv=1/7.2*40793=.0000034

That is for full flow.  To be able to regulate to +-10%, you need to be
able to modify the Cv by:

.00000034

Do you really think you can do that?   Is this the right design?


- --
Dave Gomberg, San Francisco            mailto:gomberg@wcf.com
For low cost CO2 systems that work:  http://www.wcf.com/co2iron 
Tropica MasterGrow in the USA:      http://www.wcf.com/tropica 
- -----------------------------------------------------------------


More CO2 Injection Stuff

by "Dan Dixon" <dandixon/home.com>
Date: Thu, 23 Sep 1999

Peter G. Aitken wrote:

> I have been looking into the Swagelock needle valves. The "S series metering
> valves" is indeed the lowest flow rate valve style they make. The maximum Cv
> is 0.004 (valve fully open) but according to the flow data graph I have you
> can get a Cv as low as 0.00025 with the valve open 2 of its 10 turns. I
> think this will be fine for a low pressure system - if not someone please
> enlighten me before I order one!

Peter, I don't know how useful the Cv numbers are with gasses, but most
people who have used the Nupro S valve say it's very nice. My recent
attempts to find this valve locally were not successful, but in the process
I stumbled upon a Parker HR series valve for slightly more (about $52) than
the Nupro S valve. I bought it and am so far very pleased with it.

The HR stands for "High Resolution" and the series comes in seven different
valve stem tapers (HR-0 through 6) that offer various flow coefficients. The
one I got was the HR-1, although from the spec sheets the HR-0, 2, 3, and 4
models appear to be at least as precise as the Nupro S valve. Here are the
Cv figures for the Parker HR-0 through 4 valves:

HR-0:   .00034
HR-1:   .00080
HR-2:   .00140
HR-3:   .00310
HR-4:   .00770

Here are some of the manufacturers' specs for the Nupro S and Parker HR-1
valves.
                           Nupro S Series        Parker HR-1

Max pressure:                2000 psig            250 psig
Max flow coefficient (Cv):    .004                .0008
Turns to open:               10 (+/-2)           15 (+/-1)
Shutoff:                    not intended        bubble-tight
Cv at turns open (approximate*):
        1 turn                .00010               .00005
        2                     .00025               .00007
        3                     .00050               .00008
        4                     .00080               .00010
        6                     .00180               .00015
        8                     .00280               .00025
       10                     .00400               .00035
       12                       ---                .00050
       15                       ---                .00080

(* I derived these numbers from somewhat lo-rez graphs, so they could be off
significantly)

To make sense of these numbers, I had to learn what "Cv" meant. The flow Cv
(Coefficient of volume) is defined as the number of gallons per minute of
room temperature water that will flow through the valve with a pressure drop
of 1 psi across the valve. However, since we are metering CO2 and not water,
all sorts of variables factor into the equation because gases are
compressible and the flow rates are affected by temperature and pressure.
The math to calculate flow rates for CO2 through these valves is available,
but it's beyond my time/interests/brainpower/etc. Here it is for those so
inclined:

http://www.ces.clemson.edu/~dbruce/valve6.htm

In a nutshell, the Cv numbers are relative, I think.

Since most folks who use the Nupro are apparently quite satisfied with its
control resolution, the Parker HR-1 is possibly a bit more resolution than
is needed. For people who find that they only use the lower range of the
Nupro (1 turn or less), the extra resolution of the HR valves might be
desirable.

Another nice feature is the shut-off capability. Unlike the Nupro S valves,
the Parker HR valves are *designed* to be shut off. Factor in the cost of a
ball valve and the extra expense is a bit easier to swallow.

The only downside was that the Parker came with 1/8" connectors because
that's all the dealer had. Adapting this my Cornelius regulator (aka "beer
keg guage") was problematic; 1/4" connectors would have been a lot less
hassle to hook up.

As soon as I've had more time to play with the Parker HR-1 I will post my
experiences, but so far it appears to be a very nice valve. Right now I'm
running about 20 psi into it and I open it up about 3 turns to achieve 1
bubble/sec.

BTW, I think I saw 3 or 4 more on the shelf of this dealer, so if anyone
else is interested, email me off list and I'll send dealer info. The person
who helped me said they've been collecting dust for 4 or 5 years, so they
just want to move them out. I think Parker redesigned the valve, because
their current picture on the web site differs slightly from the valve I
bought.

I also learned that it doesn't hurt to poke around locally first before
buying mail order. I was about to order the Nupro from an out-of-town dealer
when I stumbled onto the Parker deal. There may be other high resolution
metering valves out there made by other manufacturers besides Swagelok and
Parker. If you happen upon a dealer of other brands of metering valves, ask
the dealer to cross-reference thiers to a Nupro S and see what they come up
with. You never know what you may discover.

Good luck!

Dan Dixon


Cv and flow

by Erik Olson <erik/thekrib.com>
Date: Fri, 24 Sep 1999

On Thu, 23 Sep 1999, Dave Gomberg wrote:

> For gases:
> 
> If you are trying to use a valve to drop regulator output from a stable
> 10psi to the 1psi you need at the bottom of a two foot deep tank to make a
> bubble, and the gas is CO2 and the temperature is 75F, this means:
> 
> CFM=7.2*Cv; Cv=CFM/7.2
> 
> If we want 1 L (about a quart) per day, that is about 1/40700 CFM.

See, here's my problem with this: your answer is purely theoretical.
Experimental results from my own experience, as well as George and others,
shows that the rate can be adjusted quite nicely with the Nupro valves
(and not so nicely with others such as the ARO-1). So where's the
disconnect between the prediction and the results?

So first, how do we know it's 1 liter per day and not 10?  A 1mm
radius bubble per second comes out to 0.36 l per day.  A 2mm comes out to
8 times that... In my larger tanks I was going 2 or more bubbles per
second. There's an order of magnitude potential variance there.  Perhaps
this is part of the answer.

> Cv=1/7.2*40793=.0000034

= 3.4 x 10-6.  

Nupro valve Cv = 2.5 x 10-4 at two turns, this means at 1/4 turn you
might get the Cv down to 2.5 x 10-5, which is now only 1 order of
magnitude off your calculation for full flow.  Can I get finer precision
than 1/4 turn on the nupro valve?  You betcha!  There's at least another
order or magnitude here.

> That is for full flow.  To be able to regulate to +-10%, you need to be
> able to modify the Cv by:
> 
> .00000034

I submit that we don't need to regulate +/- 10%; that our reactors are not
that efficient (given loss to the atmosphere and such) that such changes
make significant difference. We are adjusting for factors of two or more.
1 bubble per second, 2 bubbles per second, etc.

  - Erik

- -- 
Erik Olson
erik at thekrib dot com


CO2 levels dangerous yet?" and other questions

by erdoz1 <erdoz1/wt.net>
Date: Mon, 27 Sep 1999

I accidentally gassed my fish when I first put the diffuser stone in the
outlet of the powerhead - the absence of bubbles slipped me up.  The Ph
went from 7.6 to about 6.2 in two hours.  According to the table in
Aquatic Concepts, my predicted CO2 level was
240ppm.  The fish were gasping at the top of the water.  I immediately
stopped the CO2 and put a lot of bubbled air into the powerhead
venturi.  The fish returned to normal about an hour later. Needless to
say, I have been more careful since.

I add CO2 using a single stage regulator and a Nupro 4MG2 valve which is
way oversized for my 135 gallon tank. According to the table, my daily
CO2 level is between 24 to 47 ppm.  The fish don't show any distress and
the plants bubble oxygen very happily.  I start with a 7.6+ Ph and 8 to
9 Kh water and adjust the additions to hit a 6.9 Ph. It takes about 6
hours to go from 7.6 to 6.9. The only fish that seem to mind the Ph
swings  are some rift lake cichlids that have eluded my nets and traps
over the past months.

For regulation. the Nupro valve is just barely cracked - I regulate
additions off the downstream gauge setting. As long as the needle valve
is not touched or jarred, you can hit the desired Ph level fairly
reliably by repeating the pressure gauge setting.

The night before the weekly 50% water change, I cut the indicated CO2
flow setting in half.  This gives me a 7.4 Ph.  I feel this Ph is close
enough to make water changes into directly.


More CO2 Injection Stuff

by erdoz1 <erdoz1/wt.net>
Date: Wed, 22 Sep 1999

In response to Dan Dixon's questions about Swagelock's numbering system
- - B-4MG2,
I don't have my Swagelok catalog home but I will wing it.

The "B" stands for "brass" (about half the cost of stainless steel)
The "M" stands for the "M" series which is valve with a Cv (capacity) of
0.03.
The "S" series has a smaller Cv - I think  0.01 - Both are too large in
my opinion (see below).

The other options refer to angle vs straight-thru- vs double (same Cv),
connection type (I prefer 1/4" NPT) .  A "MV" at the end refers to a
microvernier
control which is real cool looking, costs $40 more , but is useless if
the valve is oversized.

I installed my Swagelok B-4MG2  series valve in series with my single
stage regulator tonight and
was "disappointed".  The valve is oversized, so it is twisted way down
on the seat -just like
my calculations prediicted after the fact. (I calculated a valve Cv of
about 0.002 required.)
The needle valve  has inproved control, but not $40 worth.
I think the 2 stage regulator is the way to go.

- -  I have been using a 1/8" x 1.5" cheap plastic airstone inserted into
the air
injection port of my power head.  It works GREAT - very, very fine
dispersion with almost no bubbles making it to the surface (= 100%
utilization).  A great substitute for "reactors" if you have a power
head.

- - I appear to be using a lot of CO2 ( I am going to make a wild guess
of  at least 4 lb/100 Gal-Month)  _ I am taking a 7.6+Ph with  9 Kh
water down to 6.9 Ph.

- - The water returns to 7.6 after CO2 injections have been stopped about
4
hours

- - at 6.9 Ph and strong lighting , the plants especially the anubias and
sagittaria bubble O2
like mad (thats a good sign, I hope).


More CO2 Injection Stuff

by "Peter G. Aitken" <peter/pgacon.com>
Date: Thu, 23 Sep 1999

I have been looking into the Swagelock needle valves. The "S series metering
valves" is indeed the lowest flow rate valve style they make. The maximum Cv
is 0.004 (valve fully open) but according to the flow data graph I have you
can get a Cv as low as 0.00025 with the valve open 2 of its 10 turns. I
think this will be fine for a low pressure system - if not someone please
enlighten me before I order one! The price I was quoted, in brass with 1/4"
Swagelock fittings and the fine adjustment handle (which has a locking
screw), was about $47.

Peter G. Aitken


Needle valves

by Zxcvbob <zxcvbob/tcw.net>
Date: Thu, 23 Mar 2000

This was sent yesterday and I don't think it ever made it into the
digest. My apologies for the duplication if I just missed it somehow. 

Mark and Lisa XYZ <Lisark@arkansas.net> sez:
> I am in the process of building an aquarium and am going "mid-tech" by
> adding a pressurized C02 system.  Unfortunately I lack a needle valve to
> fine tune the amount of C02 that reaches the plants.  I was looking at
> Hoa's site and he said he found one reasonably priced (important issue)
> at NAPA, but I only got a dumb look when I asked about one here in my
> area.
> 
Yeah, I hate that dumb look.

I don't use a needle valve.  I made a flow restrictor that resembles a
"capillary tube" from an automotive air conditioner.  I took a piece of
1/4" OD copper tubing and hammered it flat in the middle until it would
just barely pass any CO2 at 10 PSI.  Then I adjust the flow rate with
the pressure setting on my regulator.  Maybe I get away with it because
I have a two-stage regulator that will maintain a stable 1 or 2 PSI (an
ancient O2 regulator that I swapped the fitting).  But in theory, it
should work at any reasonable pressure.  HTH

Bob


CO2 Flow control

by Scott Hieber <shiebernet/netscape.net>
Date: 3 Mar 00
To: erik/thekrib.com

Hello Erik,

You might find some of this information worth sharing on The Krib.   

I recently tried an ARO FO2 (1/4" NPT version of F01) on a CO2 set-up.  The
regulator was set to about 15 or so psi.  The F02 was incapable of closing
down enough to have any effect on the flow rate of C02.  I can't say precisely
what the low-side pressure is since the low-side gauge on this inexpensive
regulator indicates a flow rate (liters/min) rather than pressure.

I read that the performance of the ARO can be improved if, counterintuitively,
you turn the low-side pressure way up to about 100 psi.  Unfortunately I can't
set the regulator that a high because it has a low-side safety valve the opens
when the low side pressure gets too high.  On the plus side, this safety valve
should prevent a high pressure dump of the CO2 tank into the aquarium if the
high-side of the regulator gives out.

I tried the F02 on a $30 " CO2 " regulator from Harbor Freight (
http://www.harborfreight.com/ ).  This regulator can be adjusted low enough to
operate an Eheim C02 Reactor as low about 1 bubble/3 sec.s.  Probably as good
as I would get if the F02 actually worked.  The Eheim is actually a
check-valve, bubble counter, and diffuser stone) that operates on relatively
high pressure (in the 10-15 psi neighborhood).  On a high quality regulator
that can be reliably tuned to levels between 10 and 20 psi, a metering or
needle valve isn't necessary.  Since I won't rely on the cheap regulator to
control the CO2 flow,  I sent away for a Nupro, still available for $38.40 at
the distributors listed on your and Booth's sites plus:


	R S Crum & Corporation 
        1181 Globe Ave
        Mountainside, NJ 07092-2999
        Phone: 908-232-4444

Like McMaster-Carr and Grainger, this is basically a wholesaler and supplier
to contractors.  They accept phone orders and credit card purchases.


S. Hieber

____________________________________________________________________
Get your own FREE, personal Netscape WebMail account today at http://webmail.netscape.com.


Swagelok/Nupro metering valve site

by Scott Hieber <shiebernet/netscape.net>
Date: 15 Mar 00
To: booth/frii.com

Hello Folks,

In case you didn't have this web address, I thought you might want it for
reference on your site(s).  This web address has all the info on
Swagelok/Nupro metering valves, including the M and S series.

Select Metering Valves from the left menu on this page 
http://www.swagelok.com/Ecatalog/ecmainframes.asp?Type=24&Cat=0&SubCat=0

Select M series or S series from the middle menu.  Then select M Series or S
series from the rightmost menu.

Thanks for the help,
Scott

S. Hieber

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Source for CO2 System Fittings -- Source for Tube & Fittings

by Scott Hieber <shiebernet/netscape.net>
Date: 24 Feb 00
To: erik/thekrib.com

Hello Eric,

A while ago I asked you about what parts where needed to put together a CO2
system.  You explained that it was basically a matter of getting the
tank/guages and working from there to the "airline" using whatever pipe
fittings were necessary.  You even took the trouble to provide a sketch of a
sequence of parts that would work.  My next step was, then, to hunt down the
parts.

A message on your site mentions McMaster-Carr in the Lighting Suppliers html
(cf.:"MH ballast etc from Grainger and others" by Doug Valverde).

I think it's worth mentioning that this site ( http://www.mcmaster.com/ ) is
also an EXCELLENT source of pipe fittings and tubing of every variety.  A
comprehensive on-line catalogue depicts virtually every part they sell and has
good search functions.  This is particularly useful when hunting down that
brass pipe fitting (or plenum connection or whatever) that you know looks like
such and such (or connects this to that) but you don't know exactly what it's
called.  It also carries a range of electrical items such as ph controllers,
compressed gas cylinders/tanks, and much more.  Unlike the smaller industrial
supplier Grainger, I believe McMaster has no problem selling very small orders
or retail.  

Also, just to update, Grainger ( http://www.grainger.com/ ) is still a good
source for the Aro F01 and F02 Fine Adjustment Flow Control Valves -- I
purchased an F02 from them last week (Feb 2000) for $14.  Unfortunately, they
still only sell to contractors with established accounts.

Scott

S. Hieber

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ARO needle valves

by Larry and Lynn Fecich <bit64/isrv.com>
Date: Thu, 18 Jan 2001

While looking on the net for a mail-order place that sells ARO needle 
valves, I found a web site that carries other brands... They have (among 
others) Pneutrol brass valves for 9.80 and 10.50 (see 
http://www.gaugestore.com/gaugestore/needval18npt.html ). I don't know 
anything about this brand, so I requested more info, attached is their 
response. Lee Cooper gave me permission to post his email address here 
(Listmom, I hope this is OK). My current 'junk drawer' needle valves are 
very difficult to adjust, I may try one of these to see if it works any 
better.

- -----snip---------
Larry,

You can completely shut off the N10B or N10BK Deltrol
needle valves. They have a pretty good adjustment
needle on them so they would probably work in your
application. However, you would need to test it out
for your specific needs. The Deltrol unit is similar
and equal or better quality than the ARO unit.

We are always glad to receive any "word of mouth"
advertising. Thanks for your inquiry.

Lee Cooper
glc@gaugestore.com
phone: 800-511-0100
fax: 704-504-2478
email: info@gaugestore.com
web: http://www.gaugestore.com
mail: Industrial Automation, PO Box 411128, Charlotte NC 28241

Gaugestore.com - the best way to buy pressure gauges!


Cv and valves

by George Booth <booth/lvld.agilent.com>
Date: Thu, 14 Sep 2000

> Date: Wed, 13 Sep 2000 14:35:01 -0700
> From: Dave Gomberg <gomberg@wcf.com>
> 
> At 03:48 PM 9/13/00 -0400, Bob asked:
> >Micro-mite Forged Metering Valves: 1600 Series     Cv = 0.0008
> >
> >Is this Cv rating sufficiently low that it could be used straight off
> >the CO2 tank valve w/o a regulator?

Dave does some Rocket Science and concludes: 

> For gases:  CFM=22.7*Cv*sqrt((delP*P1)/((460+T)SG))
> <snip>
> Running straight off the tank, P1=delP=800,  so it works out like 
> Cv=3.6x10**-8 or .000000036
> 
> That's very very small.  You won't get there with a needle valve that you 
> can afford.  And it wouldn't be thermally stable anyway.

A. I would assume (perhaps incorrectly, as I am wont to do) the Cv spec for a 
valve correlates to the the maximum flow the valve will support. For instance, 
the Cv of a Nupro M series valve is 0.03 which correlates to a flow of 1.2 cubic 
feet per minute at an inlet pressure of 35 psig. I am using such a valve and I 
have it adjusted for a flow rate that seems, although not actually measured, 
considerably less than 1.2 cfm. So I assume the rated Cv is the max and the 
effective Cv gets real small as the valve is closed. So I would disagree with, 
but can't conclusively disprove, the statement that "You won't get there with a 
needle valve that you can afford." But I will eagerly nod in agreement with the 
thermal stabilty thing. 

B. I have some anecdotal evidence that such a thing may be possible, although 
not recommended. Back when we were trusting young pups, we bought a Dupla CO2 
"Starter Kit" which Daleco MBP graciously modified to use a U.S.-threaded 2.5 
pound bottle instead of the amusing 160 gm bottle Dupla supplied. The starter 
kit was composed of the bottle (no regulator), a needle valve connected directly 
to the bottle, a bubble counter, a check valve, a diffuser and the Dupla 
Continuous CO2 Test. The needle valve did indeed work although it was tricky to 
get "just right" and was thermally unstable but not dramatically so. We used 
this setup for a year before graduating to a single stage, dual gauged Air 
Products 1102 regulator, Nupro B-4MG2 valved, Eheim canister filter reactored 
five pound setup.

C. The needle valved 2.5 pound bottle often ran to empty (Doh!) but never 
"dumped", as fas as I know.  


George Booth in Ft. Collins, Colorado (booth@frii.com)
  http://www.frii.com/~booth/AquaticConcepts 


HOKE valves

by "James Purchase" <jpurch/interlog.com>
Date: Wed, 13 Sep 2000

While searching through the archives using "needle valves" as a seach term,
I came across several references to Hoke valves, all of which referred to
them highly. Only two posts came close to identifying which particular Hoke
valves might be of use, one post referring to a Hoke microregulation valve
and another post gave a part # 13354MB.

When I look at Hoke's web site (http://www.hoke.com/), their online product
catalogue shows a number of different series of valves - but it does not
resolve the part number beyond the main series:

Micro-mite Forged Metering Valves: 1600 Series     Cv = 0.0008
Milli-mite Forged Metering Valves: 1300 Series       Cv = 0.010 (1 degree
stem) ; Cv = 0.24 (3 degree stem)
Bar Stock Metering Valves: 2300 Series                  Cv = 0.012 (1 degree
stem) ; Cv = 0.077 (8 degree stem)

Anyone have any idea which of the Hoak valves are useful for our purposes?

Thanks

James Purchase
Toronto


Aquatic Plants Digest V4 #756

by "Mortimer Snerd" <mortimersnerd/uswest.net>
Date: Mon, 1 Jan 2001

Dave, and all,

Please define expensive.  My Hoke micro metering valve works extremely well,
gives me good resolution, and will shut completely off.  More expensive than
most at $40, purchased at a local industrial valve supply, but not what I
would call very expensive when compared to most of the items used in our
tanks.

Justin Collins

> Now maybe there is a valve that can be set to a Cv of .000001.   You
should
> expect that its maximum Cv would be about .0001.  But I haven't found
> it.  Hoke does make a "micro-metering" valve, but it is very expensive.


Needle valves in CO2 systems poll

by "Jamie Johnson" <jjohnson/davisfloyd.com>
Date: Wed, 3 Jan 2001

Dang it, I finally had to chime in...

20lb CO2 tank. 
National Speciality Gases single-stage, dual gauge regulator.
Nupro "S" series needle valve. I don't know the part number, just 
has an "S" on the side. My boss at work gave it to me two years 
ago. It was part of a GC/MS used to control carrier gas flows. They 
didn't need it any more, so I told them I'd take it for my CO2 
system at home. Most thought I was growing pot with CO2 and 
found it hard to believe I'd be using it for my aquariums. The guy I 
bought the CO2 tank from gave me the same strange look. I 
assured them it was perfectly legal. Those silly non-aquarists, pot 
grows better outdoors! 

The high pressure naturally sits at ~900psi (when full ;-)). I keep 
the low pressure gauge at ~15psi. 1/8" copper tubing connects the 
output Swaglok fitting to the needle valve Swaglok fitting. The 
output needle valve fitting is simply connected to 3/8" tygon tubing 
via a hoseclamp. The CO2 in injected into my filter box at 1 
bubble/2 secs, or ~28-30 per minute. The needle valve in very 
sensitive, and by that I mean you can adjust to get about any 
number of bubbles you desire. If I close the valve, everything stops 
and stays that way, even with the 15psi input. About a quarter turn 
gives me my desired rate. I love this needle valve! You can increase 
or decrease bubble flow by a bubble or two a minute. I could bump 
it up to 32 bpm if I needed to, but 28 gives me 15-20ppm CO2. It's 
been running untouched for two years. (Well I do touch it 
sometimes, but I don't have to). The tank is still reading ~900psi 
after two years. I check it once a week. 

****I will NEVER, EVER go back to yeast CO2 bottles. I did my 
time and I love the freedom I have now! (plus all the extra sugar)****

Jamie    <"\\\><
Greenwood, SC


Needle valves in CO2 systems

by "David Ozenne" <dozenne/10fold.com>
Date: Fri, 05 Jan 2001

I'm just getting caught up, so this is a bit delayed: 
 
Dave Gomberg wrote:
 
> Now assuming we set the regulator for 30psi and want 15psi out of the 
> valve, with a flow of one liter per day, we need a valve operating at a Cv 
> of .000001
 
Woah!  Not so fast there.  The Cv values quoted for valves are pretty
good for sizing valves for liquid flows, but somewhere between suspect
to downright useless for gas flows.  Particularly if you're talking
about a large absolute pressure drop across the valve (> 1.9).  I was
reminded of this when zxcvbob wrote:
 
> I suspect that at its most restrictive point, the gas
> velocity is approaching the speed of sound (thus establishing a
> maximum flow rate at any pressure).

Yes indeed!  When you hit the realm of sonic flows, you can't just use
a Cv and pretend that you're dealing with an incompressible liquid.  In
particular, a calculation using Cv will in general overestimate the gas
flow.
 
See, for example:
 
http://www.controleng.com/archives/2000/ctl0901.00/0009we1.htm
 
I have used a ARO NO1 valve to control CO2.  While it did not provide
the fine control that I would have liked, it was certainly capable of
keeping a pretty stable CO2 flow at about 1 bubble/sec with an input
pressure of ~20 psig.  I never measured output pressure, but it would
have to be considerably less than 1 psig.  This gives an absolute 
pressure ratio of over 2, so we're dealing with a sonic flow.  In this
realm, the flow rate is fairly stable with regard to changes in
the input (or output) pressure.  The Cv on this valve is nowhere near
the low numbers that Dave is looking for.

I now use this same ARO valve to restrict the maximum flow, but use
an Eheim diffusor as well, so I control my flow rate by adjusting the
regulator pressure.  And my fish recently survived a leaky connection
that allowed my CO2 tank to empty.  The only problem that I have with
this setup is that I have to make a small adjustment of the regulator
and then wait 20 minutes to see what the final stable bubble rate is.

David Ozenne
Fremont, CA



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CO2 valves & 24v transformers

by Tom Petersen <peter334/tc.umn.edu>
Date: Sun, 15 Feb 1998

Dave & Steve:

ARO is a division of Ingersoll-Rand.  The site you want to check out for
CO2 valves is:

http://aro.ingersoll-rand.com/power/valve.htm

Phones numbers and valve info is included.  If you're lucky to have a
Grainger's (multi-purpose anything you want store) they have a 3000+
page catalog that has the valves including solenoids from ARO and
others.

Subject: 
            Re: co2 systems
       Date: 
            Tue, 07 Sep 1999 12:19:57 -0700
      From: 
            Stephen Pushak <spushak@mdsi.bc.ca>
        To: 
            flyer <flyer@island.net>
        CC: 
            Michael Flegel <mpflegel@istar.ca>
 References: 
            1




Jennifer,

In Vancouver you can contact Canex Cylinders at 273-0300 (ask for Kevin
or
Dave) if you want the ARO needle valve. You should ask for the
ARO/Ingersoll-Rand part 104104-NO1 which has 1/8" NPT fittings. The
price
is about $19.75 last time I ordered one. The part will be listed in the
Fluid Products catalogue under Utility Valves.

To find a closer distributor for ARO/Ingersoll Rand you can call Tony
Leo
(416)213-4502. Or contact a local Acklands and give them all the
information above. They probably won't know ARO but will know Ingersoll
Rand and you may have to steer them to the right parts catalogue.

For a top of the line needle valve with very fine adjustment you can use
the Nupro BSS4. You can get that from Columbia Valve and Fitting Ltd
(986-5251) in Vancouver for $75.80. That is a Nupro/Swagelock part. A
vernier handle is an additional $25.65. (prices subject to change)

You will also need a regulator. You might be able to find a used oxygen
or
CO2 regulator for about $40. Mike Flegel might be able to help with a
contact number. I've CC'd Mike on this message. Oxygen regulators can be
converted to CO2 use by switching one fitting from left hand to right
hand
thread. Brand new regulators cost over $120.00 but there are many
alternatives.

You will also need some 1/8" NPT hose barb adapter(s) and other
miscellaneous fittings to join the regulator and needle valves together.
You can gang several needle valves off one regulator in order to inject
multiple aquariums. A welding supply outlet such as Weldco or Acklands
can
help you out with all those dohickeys. 

I like to use a powerhead to act as a CO2 reactor in the aquarium. See
pictures on my web pages. Its also a good idea to have a spare CO2
cylinder
to swap in when the old one runs out. It can take over a week to get one
refilled unless you lease one and exchange it.

You can also buy a ready made CO2 injection system however the CO2
cylinders are tiny and expensive to refill/replace. Talk to Jeannie at
Aquariums West if you are interested. There is another large retail
distributor chain which handles CO2 systems however I will not recommend
them. Over priced and uncooperative with the local aquarium clubs and
plant
growers.
------------------------------


More CO2 Injection Stuff

by "Dan Dixon" <dandixon/home.com>
Date: Thu, 23 Sep 1999

Peter G. Aitken wrote:

> I have been looking into the Swagelock needle valves. The "S series metering
> valves" is indeed the lowest flow rate valve style they make. The maximum Cv
> is 0.004 (valve fully open) but according to the flow data graph I have you
> can get a Cv as low as 0.00025 with the valve open 2 of its 10 turns. I
> think this will be fine for a low pressure system - if not someone please
> enlighten me before I order one!

Peter, I don't know how useful the Cv numbers are with gasses, but most
people who have used the Nupro S valve say it's very nice. My recent
attempts to find this valve locally were not successful, but in the
process
I stumbled upon a Parker HR series valve for slightly more (about $52)
than
the Nupro S valve. I bought it and am so far very pleased with it.

The HR stands for "High Resolution" and the series comes in seven
different
valve stem tapers (HR-0 through 6) that offer various flow coefficients.
The
one I got was the HR-1, although from the spec sheets the HR-0, 2, 3,
and 4
models appear to be at least as precise as the Nupro S valve. Here are
the
Cv figures for the Parker HR-0 through 4 valves:

HR-0:   .00034
HR-1:   .00080
HR-2:   .00140
HR-3:   .00310
HR-4:   .00770

Here are some of the manufacturers' specs for the Nupro S and Parker
HR-1
valves.
                           Nupro S Series        Parker HR-1

Max pressure:                2000 psig            250 psig
Max flow coefficient (Cv):    .004                .0008
Turns to open:               10 (+/-2)           15 (+/-1)
Shutoff:                    not intended        bubble-tight
Cv at turns open (approximate*):
        1 turn                .00010               .00005
        2                     .00025               .00007
        3                     .00050               .00008
        4                     .00080               .00010
        6                     .00180               .00015
        8                     .00280               .00025
       10                     .00400               .00035
       12                       ---                .00050
       15                       ---                .00080

(* I derived these numbers from somewhat lo-rez graphs, so they could be
off
significantly)

To make sense of these numbers, I had to learn what "Cv" meant. The flow
Cv
(Coefficient of volume) is defined as the number of gallons per minute
of
room temperature water that will flow through the valve with a pressure
drop
of 1 psi across the valve. However, since we are metering CO2 and not
water,
all sorts of variables factor into the equation because gases are
compressible and the flow rates are affected by temperature and
pressure.
The math to calculate flow rates for CO2 through these valves is
available,
but it's beyond my time/interests/brainpower/etc. Here it is for those
so
inclined:

http://www.ces.clemson.edu/~dbruce/valve6.htm

In a nutshell, the Cv numbers are relative, I think.

Since most folks who use the Nupro are apparently quite satisfied with
its
control resolution, the Parker HR-1 is possibly a bit more resolution
than
is needed. For people who find that they only use the lower range of the
Nupro (1 turn or less), the extra resolution of the HR valves might be
desirable.

Another nice feature is the shut-off capability. Unlike the Nupro S
valves,
the Parker HR valves are *designed* to be shut off. Factor in the cost
of a
ball valve and the extra expense is a bit easier to swallow.

The only downside was that the Parker came with 1/8" connectors because
that's all the dealer had. Adapting this my Cornelius regulator (aka
"beer
keg guage") was problematic; 1/4" connectors would have been a lot less
hassle to hook up.

As soon as I've had more time to play with the Parker HR-1 I will post
my
experiences, but so far it appears to be a very nice valve. Right now
I'm
running about 20 psi into it and I open it up about 3 turns to achieve 1
bubble/sec.

BTW, I think I saw 3 or 4 more on the shelf of this dealer, so if anyone
else is interested, email me off list and I'll send dealer info. The
person
who helped me said they've been collecting dust for 4 or 5 years, so
they
just want to move them out. I think Parker redesigned the valve, because
their current picture on the web site differs slightly from the valve I
bought.

I also learned that it doesn't hurt to poke around locally first before
buying mail order. I was about to order the Nupro from an out-of-town
dealer
when I stumbled onto the Parker deal. There may be other high resolution
metering valves out there made by other manufacturers besides Swagelok
and
Parker. If you happen upon a dealer of other brands of metering valves,
ask
the dealer to cross-reference thiers to a Nupro S and see what they come
up
with. You never know what you may discover.

Good luck!

Dan Dixon


CO2 and Needle Valves

by "Ken Guin" <kenguin/homemail.com>
Date: Wed, 22 Mar 2000

Several list members have recently asked about CO2 Bottles and Needle
Valves, so I thought I would regurgitate some information I have put on
the
APD in the past.  I bought my setups about a year ago and have been very
happy with them.

I ordered the B-SS4 Nupro Needle Valve ("S" Series) from Dibert Valve
and
Fitting Company, Inc, P.O. Box 37280, Richmond, VA 23234-7280.
(540)366-0555. If you call them, ask for Joann and mention my name. She
will
be able to check my invoice and tell you what else you need. The cost
for
the needle valve was $55.00

Dibert Valve is the local distributor for Swagelok valves. The B-SS4
model
accommodates regular air tubing. If you are using something other than
regular air tubing (1/4"OD, 3/16" ID), you will have to get different
sized
inserts than what I got. I ordered the B-405-3 inserts which fit air
tubing
like a glove. The inserts are about 50 cents apiece. I have been using
them
with the Nupra Valve for a year now and I have had no problems.

You can get a twin gauge regulator and a used (but certified) tank from
Rapids, 101 Second Avenue, SW, PO Box 396, Cedar Rapids, IA 52406
800-472-7431 http://www.4rapid1.com . I got the used ten pound cylinder
(G110) for $65 and a regulator (Norgren - RP957) for $52.50 from Rapids.

Costs:
$55.00 Valve
$65.00  Tank
$52.50 Regulator
172.50 Total

I hope this is helpful.

Ken Guin
Arlington, VA

==================

-- 
Steve Pushak                              Vancouver, BC, CANADA 

Visit "Steve's Aquatic Page"      http://home.infinet.net/teban/
 for LOTS of pics, tips and links for aquatic gardening!!!


Clippard Minimatics for CO2 fittings

by Lobos <lobos0331/yahoo.com>
Date: Thu, 15 Nov 2001

Dave,

They have some great miniature parts applicable to
aquariums.  I found this site about 6 months ago.  I
bought one of the M3 needle valves and it is made by
Clippard.  This site has some great parts for building
CO2 manifolds.  You could use the part# 15090-3-PKG as
a 2-tank manifold.  I found this site about 6 months
ago.  Unfortunately their S/H is high, $10 for my
area, but I do have a local distributor.

Lobos

<<<<<<<<Hi everyone,
I just wanted to share a source I have been using for
needle valves and 
fittings for CO2 distribution in my planted tanks. I
had been buying these 
thru a local distributor and just found out they can
be ordered directly from 
the company. I found them on a NASA advertiser's
website.

This is an excellent source for check valves, needle
valves, manifolds, 
tubing, and other air (CO2) management stuff. A neat
thing about this company 
is that they also stock adapters for converting
standard pipe (example 1/8") 
into 10-32 thread. I use their needle valves on the
CO2 regulator solenoids 
on my tanks and they do a great job. They sell metal
1/8" barbed x 10-32 
threaded airline fittings, which are nearly impossible
to find anywhere 
locally. The type needle valve I use is only $10. It
is the same type 
(appearance) as that used on the M3 CO2 regulator and
the exact unit used on 
Knop CO2 regulators. Accurate and reasonable in price.


The URL is www.clippard.com. You can order products or
a catalog online. 
Great resource for fellow gadget freaks. This stuff is
so specialized you 
would never find it at your neighborhood hardware or
Home Depot, Lowes, etc.

I found this site because I have one regulator that is
not Knop brand and has 
one of those needle valves that if you turn it 1/100th
of an inch your bubble 
rate explodes. Very imprecise. I wanted to convert it
to the type on my Knop 
regulators but couldn't find the reducer bushing to go
from 1/8" MPT to 10-32 
thread. This company sells it all.

I have no affiliation with Clippard Minimatics.

Dave>>>>>>>>


CO2 -- High Pressure/Low Pressure

by "Dixon, Steven T. (BEn)" <stdixon/ben.bechtel.com>
Date: Wed, 20 Sep 2000

Dave G. and I talk a lot about CO2, but I hadn't read his FAQ before.
Another Dave (DaTrueDave) quoted Dave G's FAQ as follows:  "A low pressure
system runs about 1 psi, a high pressure system about 15 psi. A low pressure
system is hard to regulate. The regulator will regulate well from about
10-25 psi. A low pressure system needs a way to drop the 10 psi to 1 psi.
Usually a needle valve is used, but this is not very reliable, since a
needle valve is not designed to regulate pressure, but flow. If you set the
regulator very low, the pressure will wander up and down. If you set the
needle valve almost closed (as you must to make a big pressure drop) the
flow rate will vary a lot."

I don't agree with Dave's conclusion on reliability of needle valves at all.
I've shown Dave my low pressure CO2 setup in which my Nupro fine metering
valve (M series; I would buy the S series now) puts one bubble of CO2 every
four seconds into my low pressure Dupla CO2 reactor, day after day, month
after month, just like clockwork.  Once one finds the sweet spot (a couple
of twists one way or the other) it stays right there on the money for months
at a time.  And there is no reason at all to set the regulator to an
arbitrarily low output pressure.  That's just asking for trouble.  I set
mine at 40 psi where it seems to work well.  The Nupro valve manages this
pressure (or 10 times that pressure according to the specs) quite well.  And
just to poke Dave in the ribs a little :-) my low pressure system seems to
be much more reliable that his high pressure system (regulator plus Eheim
diffuser) which I have observed wildly bubbling CO2 into Dave's tank on
several occasions.

I've reminded Dave G. of how well my low pressure system works repeatedly.
Dave often talks about $100 Hoke valves; but I can report based on 4 years
of experience that my $34 Nurpo valve also works very well and Tom Barr has
a couple of even cheaper valves that he claims work well.  (Monolith Marine
Monsters and even Pet Warehouse claim to be selling good quality fine
metering valves for reasonable prices.)  What I don't think Dave G. has ever
done is buy this type of valve and actually test to determine whether his
statement is true.  In my experience it is not.

While there are some important issues in the CO2 area, it is simply NOT as
difficult as some would make out.  I suppose I should say that based on the
recent CO2 thread and careful observation of my own setup as the bottle ran
out of gas, I have come to believe that even good quality single stage CO2
equipment with a good metering valve will dump some CO2 as the tank runs out
of gas.  I calibrated by Pinpoint pH monitor (with new probe) and took
measurements twice a day.  As the tank pressure dropped from 700 psi to 200
psi the pH dropped a total of 1.0 degrees in two steps.  The output pressure
of the regulator rose to 50 psi (25% increase) and the Nupro let enough
extra gas through to drop the pH by a whole degree over a couple of days.
This was much more than I expected and wanted.  I intend to change out the
CO2 bottle before it runs out of gas in the future.

Regards, Steve Dixon


Metering Valves - CO2

by Bruno Fernandes <SurfnTurf/hybrid8.com>
Date: Fri, 15 Sep 2000

Ok, got back from talking to a few distributors and looking at all sorts of
specs for Nupro, Parker and Hoke metering valves.  (All valves worth looking at
are metering valves - any valves specifically labelled "needle"  I've seen specs
for, are terrible by comparison.  They are all far too coarse.)

First, let me get the one I'll be skipping out of the way.  Hoke has a very
sorry-looking web site and unfortunately doesn't feature much content.  I'll
hopefully get some literature soon though (on the Micro).  Prices on these sound
like they're much higher than anything else, but they do look like they
currently have the lowest Cv, bar none.

Last year Dan Dixon mentioned he had purchased a Parker HR1 metering valve
because he was unable to locate a Nupro S.  This message is what turned me on to
Parker in the first place.  His message to APD is available in the archives but
can be found without difficulty in the Needle Valve and Solenoid page at the
Krib.  (Just search www.google.com for "parker dixon needle krib" if you can't
locate it by navigating the Krib's pages.

Dan posted the specs for the first five valves in the HR series.  There are 7 in
total.  The specs he posted, though very very nice, are unfortunately for the
older HR series.  Parker has redesigned these valves and the information on
their web site is current as of this past July.

All HR feature max inlet pressure rating of 250psig, 15 turns to open and
complete shut-off capability:

HR0 - Orifice: 0.000002, Cv 0.0004
HR1 - Orifice: 0.000083, Cv 0.0070
HR2 - Orifice: 0.000168, Cv 0.0140
HR3 - Orifice: 0.000241, Cv 0.0200
HR4 - Orifice: 0.000674, Cv 0.0300

I only listed the first five for comparison to Dan's data.  Also because the HR4
features the same Cv as the Nupro M (though it has a much smaller orifice).  The
Nupro S falls between HR2 and HR1 in terms of Cv.  The numerical designation
(HR#) in the series corresponds to the valve stem taper.  I can only guess that
the number corresponds to the degrees (no other stat is mentioned).

The other very interesting aspect of these valves (likely because they don't
bottom out at a preset gap) is that their Cv vs. turns open is very smooth and
doesn't feature the small "bump" at the lower levels that the Nupro valves do.
Unfortunately there are no graphs for air flow rates (just water, which are
obviously lower than those of the Nupro valves).

I priced the HR1 valve today in a configuration that would more than likely be
at the bottom of its price range (the option of slotted vs. standard knob and
angle vs. straight pattern don't change the price).  For a brass HR1 with 1/4
NPT ends and Buna-N seal, the price came out to $138 Canadian.  That is roughly
$92 US (at a rate of 1.5 for safety).  Oh, plus 15% tax. :)

I'm the kind of person that will sometimes go overboard, but that is just a bit
hard to swallow.  Tonight I located another Parker series, the NS:

1 degree taper, 13 turns to open (+/- 1), Cv = 0.039 for straight (0.042 for
angle), rated to inlet pressure of 2000 psig, factory-set stem-stop at 2cc/min
flow at 80psig (!) - don't know if that's measured with water or air.  If air,
that sounds super-slow, if water...  Air will be significantly higher.

In addition this one is also available with a torque handle for very precise
adjustment.  There are two more (NL and NM) valves with higher Cv.

Anyway, I'd really be interested in what people think of the specifics.  I was
able to find Nupro S valves at only a slightly higher cost than M (+ $7-15)
locally.  They were between $62 and $70 CAD (featuring 1/8 and 1/4 Swagelock
fittings).  I will call for pricing on the Parker NS to see how much lower it is
than the HR series and to compare to the Nupro M.

As James also mentioned, hope people don't mind all the specs and tech info
being posted.  There really isn't any better forum for this info that I know of
- - unless someone were to start a tech-specific list. :)

Bruno -

I hope I didn't make a mess of anything.  I've been driving and walking around
all day like a zombie (flu with full gamut of symptoms), in and out of
distributors for all sorts of stuff.


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This page was last updated 17 February 2002