Metering(needle) valves for our DIY CO2 system

bettatail

Guru Class Expert
Apr 1, 2011
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Left C
I just been lucky and got a hold of large amount of swagelok M series metering valves, and test about 5 of them, the best result is 1/8 of turn 1 bubble, and as you mention, after pass 1/2 of turn from 2 bubble per second, the increase of bubbles is jumping and the 1/8 turn per bubble precision is gone, but lucky most of us adjust it and use it on 2-5 bubbles range.
Also, use alcohol to clean the needle valve is really help, under low pressure output any grease or debris stuck in the stem and orifice wall metal to metal contact area may affect the adjustment. rise the output pressure this problem is non exist but the adjustment precision is lower since flow rate increase.

I haven't heard any body said anything about SMC AS1000 series needle valve, and from the technical spec chart the flow rate of this valve is really close to the fabco valve,
it may be a good alternative since this valve is low on the price($16 new), but most of them are M5 ports since its Japanese made.
I have 5 of them, 10-32 ports, and will do a test, will see what is the result.
If you want to get your hands on SMC AS1000 series, you need to look for the AS1200 model(M5 or 10-32 port), from ebay, they can be as cheap as $4 per, and see how they work because I can not justify this valve alone.
 

bettatail

Guru Class Expert
Apr 1, 2011
155
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Update, SMC needle valve
flow rate comparison at low turn range.

comparisonJPG.jpg
 

jaidexl

Prolific Poster
Oct 17, 2006
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6
Fort Myers Florida
Are vernier handles mounted or calibrated the same on every Swagelok valve of the same series? Could folks using them share info like "0.5/17" in place of "3bps"?
 

oldpunk

Guru Class Expert
Dec 1, 2009
427
4
18
Those vernier handles really only serve as a reference point for us. Say you find 1 bubble per minute. You could then set the zero point there. There's no way you could find a generic 3 bps for all of them. There are too many variables.
 

Beachkrazd

Junior Poster
Feb 2, 2010
10
0
1
Texas, USA
I set up my first pressurized CO2 system this weekend (Victor 253B regulator, Burkert solenoid and in-line glass bubble counter). Today I put it all together and started it up for the first time. I am using the brass Ideal needle valve with vernier handle, but when I turn the vernier handle on the needle valve there is no change in bubble rate. Is there a chance that it is broken or is there a particular way that I should be adjusting the vernier handle?
 

Beachkrazd

Junior Poster
Feb 2, 2010
10
0
1
Texas, USA
Beachkrazd: I set up my first pressurized CO2 system this weekend (Victor 253B regulator, Burkert solenoid and in-line glass bubble counter). Today I put it all together and started it up for the first time. I am using the brass Ideal needle valve with vernier handle, but when I turn the vernier handle on the needle valve there is no change in bubble rate. Is there a chance that it is broken or is there a particular way that I should be adjusting the vernier handle?

Oldpunk: what's your working pressure at and what are you using to diffuse the co2?

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When I turn the working pressure up to around 10 psi the bubbles overwhelm for the bubble counter, and the CO2 pushes all of the water out of the glass bubble counter. So to control the bubble rate I had to set the working pressure to less than 5 psi, just enough to get about 1 bubble per second. I'm using a Red Sea reactor 500 for diffusion.

Since I'm brand new to pressurized CO2, I was wondering if there is an ideal working pressure that I should be using? And is there a particular way to use a needle valve because so far I do not notice any change in bubble rate when I turn the vernier handle. I would really appreciate any information you all might be able to provide. I feel like I am so close to understanding this technology, and I'm hoping to eventually have healthy plant growth in my tank. :)
 
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Left C

Lifetime Members
Sep 26, 2005
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Burlington, NC
Make sure that they Vernier handle is not loose on the needle valve's shaft. I believe it uses a very small Allen set screw to hold it down.

Also, just remember that you can increase the bubble count by either increasing the working pressure or opening the needle valve more or a combination of both means. In your case, it sounds like your needle valve was open too far causing you to have too much bubble production in your bubble counter.
 

Left C

Lifetime Members
Sep 26, 2005
2,500
1
36
69
Burlington, NC
Make sure that they Vernier handle is not loose on the needle valve's shaft. I believe it uses a very small Allen set screw to hold it down.

Also, just remember that you can increase the bubble count by either increasing the working pressure or opening the needle valve more or a combination of both means. In your case, it sounds like your needle valve was open too far causing you to have too much bubble production in your bubble counter.
 

bettatail

Guru Class Expert
Apr 1, 2011
155
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Parker HR series metering valve is currently available on ebay, the part number is 2F-H3L-*, it is 1/8" npt female connection(2F-), and high precision 3 degree, straight/Line version (H3L), grab it while you can.
 

bettatail

Guru Class Expert
Apr 1, 2011
155
0
16
People, the parker hannifin H3L is more than what I thought,

$800+ retail

$200+ used, liquidator price.