Is there such a thing as a 0-10V DC control regulator? Maybe something that would effectively be a third stage (so you can't go above your second stage limit), to let you do variable output, controlled by an Apex or similar?
Precision flow valves selection for our CO2 pressurized system
Precision Metering valve, needle valve and flow control/controller
This is a new info thread, the old thread started in 2011, I have stopped adding info since 2014, six year passed.
The old metering valve selection thread
--Metering valve:
Most are high precision flow rate control valves, they are easy to adjust low flow rate and prevent/limit unexpected flow rate purge caused by the regulator output pressure fluctuation/drop.
--Low flow control flowmeters:
control and monitor actual steady co2 flow rate. These flowmeters often can be found equipped with high precision flow control valves. No bubble counter needed. Check Brooks, Porter, Aalborg, and Matheson valves below.
* Cv value. There is a math/formula to calculate the CV value for metering valves. For our co2 pressurized system, a metering valve that can handle the gas flow CV rate down to approximately 0.00025(output pressure 40psi, back pressure 25psi, at 15sccm), is within the precision range.
The CV value of different metering valves on this thread, are "max", so to see if within the 0.00025 range, check their official .pdf for CV vs. Turn chart.
*Why 15 SCCM?
Typical flow rate for a 5lb co2 cylinder/tank, on a 6 month, 8 hours a day usage.
5lb co2 tank X 243 liter/LB X 1/6month X 1month/30days X 1day/8hours X 1hour/60minutes = 14sccm(or 14ml/minute)
* Optimal co2 output pressure
The best output pressure setting for easy co2 flow control/adjustment on a high precision metering valve, is approximately regulator output pressure equals 1 and 1/2 of back pressure.
Back pressure--The pressure down range of a metering valve(Normally the working pressure of a diffuser plus check valve holding pressure).
Pneumadyne (Pneumatic Control System), made in UK
[STRIKE]700 series needle valve[/STRIKE], Part number: C070301/C070501/C070601,
Orifice: N/A
Cv: 0.09 (at 12 turn full open)
This valve is not a precision control valve.
Clippard
MNV-3/4 series needle valve, part number MNV-3* , MNV-4*
Orifice: 0.07"(MNV-3), 0.067"(MNV-4)
Cv: N/A (at 4 turn SCFM is 1, Cv is under 0.03 before 4 turns, after 4 turns, Cv spike)
This valve is not a precision control valve.
SMC
AS1000 Series needle valve, Part number AS120?-*
Orifice: N/A
Cv: N/A
This valve is not a precision control valve.
Ideal valve
52(brass)/54(stainless steel)--1 series, Part number 52-1-, 54-1-
Orifice: 0.0313"
Cv: 0.019 (at 20 turn, 22-24 turn full open, approximate Cv 0.008 -0.009 at 10 turn)
52(brass)/54(stainless steel)--2 series, Part number 52-2-, 54-2-
Orifice: 0.0625"
Cv: 0.082 (at 20 turn, 22-24 turn full open)
Fabco-air
NV55/FC55 needle valve, Part number NV-55, NV-55-18, FC-55
Orifice: N/A
Cv: N/A
Swagelok precision metering valve,
S series high precision metering valve, Part number SS(B)-SS* , SS(B)-SM*
Orifice: 0.032"
Cv: 0.004 (at 10 turn full open)
double pattern, dual handles
Cv: 0.001 ( at 10 turn full open)
M series metering valve, Part number SS(B)-?MG*, SS(B)-?MA*
Orifice: 0.056"
Cv: 0.03 (at 9 turn full open)
double pattern, dual handle
Cv: 0.026 ( at 9 turn full open)
21/22 series metering valve, Part number: -21???-, -22???-,
Orifice: 0.02"
Cv: 0.007 (at 8 turn full open)
[STRIKE]Swagelok O series needle valve, soft seat stem. Part number SS(B)-OR*[/STRIKE]
Orifice: 0.08"
Cv: 0.09 (at 8 turn full open)
Parker Hannifin
(Bronkhorst)HR series high precision metering valve, there are 7 models, mark number from 0 to 6.
Stem type 0, Part number: -H0?---
Orifice:N/A
Cv: 0.0004 (at 15 turn full open)
Stem type 1, Part number: -H1?---
Orifice:N/A
Cv: 0.007 (at 15 turn full open)
Stem type 2, Part number: -H2?---
Orifice:N/A
Cv: 0.014 (at 15 turn full open)
Stem type 3, Part number: -H3?---
Orifice:N/A
Cv: 0.021 (at 15 turn full open)
Stem type 4, Part number: -H4?---
Orifice:N/A
Cv: 0.032 (at 15 turn full open)
Stem type 5, Part number: -H5?---
Orifice:N/A
Cv: 0.049 (at 15 turn full open)
Parker NS and NM series metering valve
NS series, Part number -NS?---
Orifice: N/A
Cv: 0.042 (at 14 turn full open)
NM series, Part number -NM?----*
Orifice: N/A
Cv: 0.055 (at 14 turn full open)
Porter/parker Flowmeter
With NR series flow control valve (0,1,2,3) or low flow (Normal) needle valve
low flow tube number:
F65/65 flowmeter a-125-3 ; a-125-5.
F150/150 flowmeter b-125-6; b-125-10 ; b-125-20.
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.[/STRIKE]
Flowmeter tube calibration data available but they are hidden on official website
Hoke
Micromite 1600 series metering valve.
Orifice: 0.031"
Cv: 0.0008 (at 18 turn full open)
Millimite 1300 series metering vale, 1 degree angle stem.
Orifice: 0.047"
Cv: 0.011 ( at 18 turn full open)
Millimite 1300 series metering vale, 3 degree angle stem.
Orifice: 0.047"
Cv: 0.024 ( at 18 turn full open)
[STRIKE]Hoke 2300 series metering valve[/STRIKE], 1 degree angle stem
Orifice: 0.062"
Cv: 0.01 (at 20 turn full open )
Brooks instrument
Low flow NRS needle control valve, Model 8503, 8504, 8513, 8514.
8503, angle pattern, normal handle
8504, straight(inline) pattern, normal handle
8513, angle pattern, digital handle
8514, straight(inline) pattern, digital handle
stem type Cv.
type 6, CV: 0.052
type 5, CV: 0.017
type 4, CV: 0.0057
type 3, CV: 0.0013
type 2, CV: 0.00066
type 1, CV: 0.00029
These valves are also found on Brooks Sho-rate and OMEGA flowmeters.
Brooks Sho-rate 1350/1355 flowmeter low flow glass tube model number:
R-2-65-A, R-2-65-B (1350)
R-2-15-AAAA, R-2-15-AAA, R-2-15-AA [STRIKE]R-2-15-D[/STRIKE] (1355)
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.
[/STRIKE]Flowmeter tube calibration data not available on Brooks official website
--Brooks pressure flow control valves model 8744, 8944, 8844 and some others, are combined with NRS valves as well.
Key instruments
(Now belongs to Brooks instruments)
Key instruments CVP valves (precision control valves)
8 models, model 1,2,3 are really good for low flow control
key instruments flowmeters:
Model GR/GD, low flow tube number 1G01, 1G02, and 6G01, 6G02.
(New version of GR/GD are Brooks 1250/1255 flowmeters, low flow tube number D6011, D6021, D6023,/ D1021, D1022)
GS series, low flow tube number GS101*,GS102*.
Flowmeter tube calibration data not available on Brooks official website
Aalborg/Dakota High precision metering needle valve
there are 6 models of this valve, model 1, 2, 3 are ok for low flow control.
These valves are often found on
aalborg/cole palmer/gilmont 150mm and 65mm flowmeters.
low flow Glass tube models for flow meter: 032 tube, 042 tube, and 052 tube with glass floating ball.
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.[/STRIKE]
Flowmeter tubes calibration data not available on Aalborg/cole palmer official website
Matheson
4170 precision metering valve, High Accuracy
There are 6 models, model 1, 2, 3 are ok for low flow control.
These valves are often found on matheson flowmeters.
FM1050 flowmeter, low flow glass tube models number: 610A(E910), 600(E100), 601(E200).
Flowmeter scale/air to co2 flow rate conversion charts are available on official website.
Dywer flow meter
Series DR Glass flowmeter(same as Matheson FM1050/FM1000)
Series VA Glass flowmeter(same as Aalborg/Cole Palmer 150mm and 65mm flowmeter)
Series RMA polycarbonate flowmeter, model RMA-151, RMA-150
Bellow are some more other good valves, rare or exotic.
Ham-Let metering valve
HXF1300 series metering valve, 1 degree stem angle, Part number HXF13??--
Orifice: 0.03"
Cv: 0.004 (at 11 turn full open)
HF1300 series metering valve, 3 degree stem angle, Part number HF13??--
Orifice: 0.055"
Cv: 0.03 (at 11 turn full open)
Fujikin metering valve , made in Japan
PUN series metering valve, made in Japan
Orifice: N/AMM
Cv: 0.004 (at 10 turn full open)
UN/DUN series
Orifice: 1.5MM
Cv: 0.015 (at 14 turn full open)
UN series metering valve, L mark on top of the vernier handle, made in Japan
Orifice: 1.8MM
Cv: 0.03 (at 14 turn full open)
Mott porous metal flow restrictor
Some models of the Mott flow restrictors provide co2 flow rate good for planted aquarium, specific detail please check official website(Mott Corp.)
Porter(parker)
VCD-1000 pressure flow controller
(hewlett packard HP19362)
Kofloc/kojima precision needle valve,
2412 series, 2203/2204 pressure flow controller
Vogtlin High Precision flow control valve,
M-flow micro flow valve, Made in Germany
Witt Gas,
high precision metering valve.
Chell Ultra-Fine Mechanism Needle Valve, Made in UK
Also name Negretti, or Meggitt
Vacoa/Vici/condyne valve
Please let me know if you see any other metering valves that not here and can be used in our DIY CO2 pressurized system.
![]()
This is a new info thread, the old thread started in 2011, I have stopped adding info since 2014, six year passed.
The old metering valve selection thread
--Metering valve:
Most are high precision flow rate control valves, they are easy to adjust low flow rate and prevent/limit unexpected flow rate purge caused by the regulator output pressure fluctuation/drop.
--Low flow control flowmeters:
control and monitor actual steady co2 flow rate. These flowmeters often can be found equipped with high precision flow control valves. No bubble counter needed. Check Brooks, Porter, Aalborg, and Matheson valves below.
* Cv value. There is a math/formula to calculate the CV value for metering valves. For our co2 pressurized system, a metering valve that can handle the gas flow CV rate down to approximately 0.00025(output pressure 40psi, back pressure 25psi, at 15sccm), is within the precision range.
The CV value of different metering valves on this thread, are "max", so to see if within the 0.00025 range, check their official .pdf for CV vs. Turn chart.
*Why 15 SCCM?
Typical flow rate for a 5lb co2 cylinder/tank, on a 6 month, 8 hours a day usage.
5lb co2 tank X 243 liter/LB X 1/6month X 1month/30days X 1day/8hours X 1hour/60minutes = 14sccm(or 14ml/minute)
* Optimal co2 output pressure
The best output pressure setting for easy co2 flow control/adjustment on a high precision metering valve, is approximately regulator output pressure equals 1 and 1/2 of back pressure.
Back pressure--The pressure down range of a metering valve(Normally the working pressure of a diffuser plus check valve holding pressure).
Pneumadyne (Pneumatic Control System), made in UK
[STRIKE]700 series needle valve[/STRIKE], Part number: C070301/C070501/C070601,
Orifice: N/A
Cv: 0.09 (at 12 turn full open)
This valve is not a precision control valve.
Clippard
MNV-3/4 series needle valve, part number MNV-3* , MNV-4*
Orifice: 0.07"(MNV-3), 0.067"(MNV-4)
Cv: N/A (at 4 turn SCFM is 1, Cv is under 0.03 before 4 turns, after 4 turns, Cv spike)
This valve is not a precision control valve.
SMC
AS1000 Series needle valve, Part number AS120?-*
Orifice: N/A
Cv: N/A
This valve is not a precision control valve.
Ideal valve
52(brass)/54(stainless steel)--1 series, Part number 52-1-, 54-1-
Orifice: 0.0313"
Cv: 0.019 (at 20 turn, 22-24 turn full open, approximate Cv 0.008 -0.009 at 10 turn)
52(brass)/54(stainless steel)--2 series, Part number 52-2-, 54-2-
Orifice: 0.0625"
Cv: 0.082 (at 20 turn, 22-24 turn full open)
Fabco-air
NV55/FC55 needle valve, Part number NV-55, NV-55-18, FC-55
Orifice: N/A
Cv: N/A
Swagelok precision metering valve,
S series high precision metering valve, Part number SS(B)-SS* , SS(B)-SM*
Orifice: 0.032"
Cv: 0.004 (at 10 turn full open)
double pattern, dual handles
Cv: 0.001 ( at 10 turn full open)
M series metering valve, Part number SS(B)-?MG*, SS(B)-?MA*
Orifice: 0.056"
Cv: 0.03 (at 9 turn full open)
double pattern, dual handle
Cv: 0.026 ( at 9 turn full open)
21/22 series metering valve, Part number: -21???-, -22???-,
Orifice: 0.02"
Cv: 0.007 (at 8 turn full open)
[STRIKE]Swagelok O series needle valve, soft seat stem. Part number SS(B)-OR*[/STRIKE]
Orifice: 0.08"
Cv: 0.09 (at 8 turn full open)
Parker Hannifin
(Bronkhorst)HR series high precision metering valve, there are 7 models, mark number from 0 to 6.
Stem type 0, Part number: -H0?---
Orifice:N/A
Cv: 0.0004 (at 15 turn full open)
Stem type 1, Part number: -H1?---
Orifice:N/A
Cv: 0.007 (at 15 turn full open)
Stem type 2, Part number: -H2?---
Orifice:N/A
Cv: 0.014 (at 15 turn full open)
Stem type 3, Part number: -H3?---
Orifice:N/A
Cv: 0.021 (at 15 turn full open)
Stem type 4, Part number: -H4?---
Orifice:N/A
Cv: 0.032 (at 15 turn full open)
Stem type 5, Part number: -H5?---
Orifice:N/A
Cv: 0.049 (at 15 turn full open)
Parker NS and NM series metering valve
NS series, Part number -NS?---
Orifice: N/A
Cv: 0.042 (at 14 turn full open)
NM series, Part number -NM?----*
Orifice: N/A
Cv: 0.055 (at 14 turn full open)
Porter/parker Flowmeter
With NR series flow control valve (0,1,2,3) or low flow (Normal) needle valve
low flow tube number:
F65/65 flowmeter a-125-3 ; a-125-5.
F150/150 flowmeter b-125-6; b-125-10 ; b-125-20.
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.[/STRIKE]
Flowmeter tube calibration data available but they are hidden on official website
Hoke
Micromite 1600 series metering valve.
Orifice: 0.031"
Cv: 0.0008 (at 18 turn full open)
Millimite 1300 series metering vale, 1 degree angle stem.
Orifice: 0.047"
Cv: 0.011 ( at 18 turn full open)
Millimite 1300 series metering vale, 3 degree angle stem.
Orifice: 0.047"
Cv: 0.024 ( at 18 turn full open)
[STRIKE]Hoke 2300 series metering valve[/STRIKE], 1 degree angle stem
Orifice: 0.062"
Cv: 0.01 (at 20 turn full open )
Brooks instrument
Low flow NRS needle control valve, Model 8503, 8504, 8513, 8514.
8503, angle pattern, normal handle
8504, straight(inline) pattern, normal handle
8513, angle pattern, digital handle
8514, straight(inline) pattern, digital handle
stem type Cv.
type 6, CV: 0.052
type 5, CV: 0.017
type 4, CV: 0.0057
type 3, CV: 0.0013
type 2, CV: 0.00066
type 1, CV: 0.00029
These valves are also found on Brooks Sho-rate and OMEGA flowmeters.
Brooks Sho-rate 1350/1355 flowmeter low flow glass tube model number:
R-2-65-A, R-2-65-B (1350)
R-2-15-AAAA, R-2-15-AAA, R-2-15-AA [STRIKE]R-2-15-D[/STRIKE] (1355)
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.
[/STRIKE]Flowmeter tube calibration data not available on Brooks official website
--Brooks pressure flow control valves model 8744, 8944, 8844 and some others, are combined with NRS valves as well.
Key instruments
(Now belongs to Brooks instruments)
Key instruments CVP valves (precision control valves)
8 models, model 1,2,3 are really good for low flow control
key instruments flowmeters:
Model GR/GD, low flow tube number 1G01, 1G02, and 6G01, 6G02.
(New version of GR/GD are Brooks 1250/1255 flowmeters, low flow tube number D6011, D6021, D6023,/ D1021, D1022)
GS series, low flow tube number GS101*,GS102*.
Flowmeter tube calibration data not available on Brooks official website
Aalborg/Dakota High precision metering needle valve
there are 6 models of this valve, model 1, 2, 3 are ok for low flow control.
These valves are often found on
aalborg/cole palmer/gilmont 150mm and 65mm flowmeters.
low flow Glass tube models for flow meter: 032 tube, 042 tube, and 052 tube with glass floating ball.
[STRIKE]Flowmeter scale/air to co2 flow rate conversion charts are available on official website.[/STRIKE]
Flowmeter tubes calibration data not available on Aalborg/cole palmer official website
Matheson
4170 precision metering valve, High Accuracy
There are 6 models, model 1, 2, 3 are ok for low flow control.
These valves are often found on matheson flowmeters.
FM1050 flowmeter, low flow glass tube models number: 610A(E910), 600(E100), 601(E200).
Flowmeter scale/air to co2 flow rate conversion charts are available on official website.
Dywer flow meter
Series DR Glass flowmeter(same as Matheson FM1050/FM1000)
Series VA Glass flowmeter(same as Aalborg/Cole Palmer 150mm and 65mm flowmeter)
Series RMA polycarbonate flowmeter, model RMA-151, RMA-150
Bellow are some more other good valves, rare or exotic.
Ham-Let metering valve
HXF1300 series metering valve, 1 degree stem angle, Part number HXF13??--
Orifice: 0.03"
Cv: 0.004 (at 11 turn full open)
HF1300 series metering valve, 3 degree stem angle, Part number HF13??--
Orifice: 0.055"
Cv: 0.03 (at 11 turn full open)
Fujikin metering valve , made in Japan
PUN series metering valve, made in Japan
Orifice: N/AMM
Cv: 0.004 (at 10 turn full open)
UN/DUN series
Orifice: 1.5MM
Cv: 0.015 (at 14 turn full open)
UN series metering valve, L mark on top of the vernier handle, made in Japan
Orifice: 1.8MM
Cv: 0.03 (at 14 turn full open)
Mott porous metal flow restrictor
Some models of the Mott flow restrictors provide co2 flow rate good for planted aquarium, specific detail please check official website(Mott Corp.)
Porter(parker)
VCD-1000 pressure flow controller
(hewlett packard HP19362)
Kofloc/kojima precision needle valve,
2412 series, 2203/2204 pressure flow controller
Vogtlin High Precision flow control valve,
M-flow micro flow valve, Made in Germany
Witt Gas,
high precision metering valve.
Chell Ultra-Fine Mechanism Needle Valve, Made in UK
Also name Negretti, or Meggitt
Vacoa/Vici/condyne valve
Please let me know if you see any other metering valves that not here and can be used in our DIY CO2 pressurized system.
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1 - 20 of 64 Posts
fellow planted tank hobbyists, don't just look, if you have found any good one base on the info provided here, sound out.
After I did the research a while ago, I gathered at least one of each of most flow control valves models here, still need time to test them.
Some of the rare brands/models, I still don't have any luck to locate them, need your help if you are that luck person, please post a picture and your experience applying the rare brand/models metering valve in the co2 system.
After I did the research a while ago, I gathered at least one of each of most flow control valves models here, still need time to test them.
Some of the rare brands/models, I still don't have any luck to locate them, need your help if you are that luck person, please post a picture and your experience applying the rare brand/models metering valve in the co2 system.
as for today, this info thread is mostly completed.
I will add pictures of different metering valves
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nice collection of the HR series. I don't see the H4.
H3L is definitely a beast. I bought a bunch many years ago when they were on sale for $8 each.
Slowly gave them to friends/other hobbyists over the years, but still have a few left for myself
Slowly gave them to friends/other hobbyists over the years, but still have a few left for myself
I do have one H4 with turn counter handle, but don't know where I put it, it is precision metering valve but a little bit off the range for extremely low flow rate adjustment, same as H5, H6.
There are some H4 on the evilbay, around $25 each, but no turn counter handle.
it seems back in 2011 anyone read this thread all got themselves at least one nice H3L, and then nice high end DIY co2 systems as self accomplishment.H3L is definitely a beast. I bought a bunch many years ago when they were on sale for $8 each.
Slowly gave them to friends/other hobbyists over the years, but still have a few left for myself
ready to build a nice co2 system with the H3L metering valve again?
Is this fixable? Needle broke inside the body, anyway to get it out? no grip for a twzeeter...
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Thanks for the heads up! This is the type of adapter one would need to fit this to something in 1/8 npt right?
1 - 20 of 64 Posts
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