CO2 Controller Needle Valves and Solenoids
Contents:
- Cheap Solenoid valve for CO2?
by gb-at-dixie.cs.unc.edu (Gary Bishop) (8 Sep 93)
- CO2 regulators and solenoids ?
by poulter-at-access1.digex.net (Harry D. Poulter) (1 Mar 1994)
- Solenoid valves--Where to find????
by sanford1-at-ix.netcom.com (gary sanford) (28 Feb 1995)
- CO2 w/o regulator
by "Jamil Zainasheff" <jamil_zainasheff-at-internet.uscs.com> (12 Jun 1995)
- CO2 Needle Valves
by steveb-at-bga.com (Steve Benz) (Wed, 8 May 1996)
- Teflon tape
by huntley-at-ix.netcom.com (Wright Huntley ) (Thu, 9 May 1996)
- Nupro valve
by Jeff & Denise Dietsch <dietsch/voicenet.com> (Wed, 10 Sep 1997)
- [Fwd: flow valves]
by Marque Crozman <mcrozman/eng.uts.edu.au> (Sat, 30 Aug 1997)
- Hoke valves
by Justin David Collins <n9720235/cc.wwu.edu> (Wed, 3 Feb 1999)
- Adjustment of Nupro Valves
by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com> (Mon, 1 Feb 1999)
- Nupro "S" Valve
by "Dixon, Steven T. (Exchange)" <stdixon/ben.bechtel.com> (Sat, 26 Dec 1998)
- ARO F01 needle Valves
by Pat Bowerman <bowerman/specent.com> (Wed, 31 Dec 1969)
- Cv and flow
by Dave Gomberg <gomberg/wcf.com> (Thu, 23 Sep 1999)
- More CO2 Injection Stuff
by "Dan Dixon" <dandixon/home.com> (Thu, 23 Sep 1999)
- Cv and flow
by Erik Olson <erik/thekrib.com> (Fri, 24 Sep 1999)
- CO2 levels dangerous yet?" and other questions
by erdoz1 <erdoz1/wt.net> (Mon, 27 Sep 1999)
- More CO2 Injection Stuff
by erdoz1 <erdoz1/wt.net> (Wed, 22 Sep 1999)
- More CO2 Injection Stuff
by "Peter G. Aitken" <peter/pgacon.com> (Thu, 23 Sep 1999)
- Needle valves
by Zxcvbob <zxcvbob/tcw.net> (Thu, 23 Mar 2000)
- CO2 Flow control
by Scott Hieber <shiebernet/netscape.net> ( 3 Mar 00)
- Swagelok/Nupro metering valve site
by Scott Hieber <shiebernet/netscape.net> (15 Mar 00)
- Source for CO2 System Fittings -- Source for Tube & Fittings
by Scott Hieber <shiebernet/netscape.net> (24 Feb 00)
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.
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 $3.25 in
"apparently new" condition - Jan 94 catalog, item #21785. They also have in
general the most enjoyable catalog around. (Hey, I'm just a happy customer).
Their no. is 708-982-0870
Another good source for surplus industrial-type equipment is
Herbach and Rademan 215-788-5583 (I have an old catalog, so this might
not be right)
by sanford1-at-ix.netcom.com (gary sanford)
Date: 28 Feb 1995
Newsgroup: alt.aquaria,rec.aquaria,sci.aquaria
In <3ito3n$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!
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? :)
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
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!
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
by Marque Crozman <mcrozman/eng.uts.edu.au>
Date: Sat, 30 Aug 1997
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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.
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
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
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
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?
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
- -----------------------------------------------------------------
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
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
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
http://www.frii.com/~booth/AquaticConcepts/, 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.
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).
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
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
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
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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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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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