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Proportional Solenoid Valve


indyspirits

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I'm looking to replace our simple on/off solenoid valve used for deplegmator temp control with a true proportional valve.  Our current valve is an Asco but that I can find, they don't offer a proportional value with 1/2 fittings, only 1/4 and 3/8.  The on/off valve is noisy, can cause water hammer, and I I'd like a bit more control over flow. Any recommendations?

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True proportional valves are going to be either ball or globe style, and are going to require a proportional output signal from your controller, like a 0-10v or 0-20ma (or 4-20ma) output.

There are a few manufacturers, but we are using a few from Johnson Controls and Belimo.  Sizing the proportional valve is going to be a little bit more complicated than with a solenoid.  Are you using municipal water for cooling, or do you have a recirculating/chiller setup?  Using city water, you'll likely be using a much smaller valve, with smaller Cv, than with recirculating, which would have a larger diameter and higher Cv.  Likewise, a smaller still with lower flow requirements will get by with a smaller valve than something larger.

One thing to watch out for with proportional valves (ball or globe) is their speed.  There are proportional ball valves with full swing timings of 90-120 seconds, these are a little bit too slow.  Ideally, the faster the actuation, the more responsive the system will be to change, however the faster the actuation, the more expensive the actuator.

You want some example model numbers?

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If you have got Silk City's queries sorted then your easiest and probably cheapest is to get a couple of 1/2 X 3/8 reducers. With the proportional valve the instantaneous flow will be much lower and you can get away with a smaller valve.

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Shouldn't be a problem providing a signal although it would simplify my wife if I could use PWM.  Currently we're using muni water for cooling -- it's fantastic in the winter but total shit in the summer. Needless to say we're looking for a closed loop replacement but we're a bit space constrained.  Regarding speed -- considering the fact that I will be very slowing requiring more flow that slightly-quicker-than-glacial full swing time should be fine.

 

This all got me thinking... perhaps I should just add a  <$20 water hammer arrestor and be done with it. I'm not necessarily disappointed with the control I get. Hell I ran it manually for over a year. Sometimes simpler is better.

 

 

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31 minutes ago, lokibrew said:

Anyone using these for dephlegmator control??

 

Not that brand. Have tried similar types of valves, and generally the thermal mass and response time are not appropriate for dephlegmator control on smaller stills. Might work with larger ones.

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Mechanical temperature control valves work very well for condenser temperature control, but they are not very useful in a dephlegmator control scenario, where you want to be making changes to the dephlegmator set point thus impacting the reflux ratio/output proof.

We have great experience with both the Johnson and Belimo proportional ball valve actuators on our still.  We are using them for both dephlegmator and product condenser temperature control.

For the Johnson Controls, The 9104-GGA-2 is a nice actuator, proportional control for the smaller valves.  It's a 60 second swing valve, which is fast enough for condenser control - during the run they barely move once they have a set position.  The 9108-GGA-2 is nice for larger valves if you are running a recirc setup and need to swing a big 1-1.5" three way.  For the Johnson valves, the GGA is critical as this represents the proportional control models.  Nice thing about the 9108-GGA-2 is that it's faster, about 25 seconds full swing.

Harder to find, and very expensive, are the Belimo high speed actuators.  I have the LRQB24-MFT - this is 5 seconds full swing, with some incredible positioning capability.  The slower LRB24-MFT are also very good, but very slow (good for PC, probably not so good for dephlegmator).

All these actuators are paired with the appropriate ball valves, 2 or 3 way, in numerous sizes and different CV sizing.

eBay is a great place to find these, you can get them for as low as $30-50, and sometimes you luck out finding the actuator already paired to the right size valve.

Good electronic globe valve positioners are incredibly expensive.  For example, the Siemens Landis MXG magnetic positioners.  This is a Rolls-Royce positioner.  Nearly instantaneous positioning (less than 2 seconds full swing) with something like 1000:1 rangeability.

We're using all of these in a pumped/recirculating setup.  I have played around with numerous types and sizes of proportional valves, so just ask, I've probably played around with it.

Hardest part of this is valve sizing and then tuning your PID control, picking up an actuator and plumbing it in is very easy.  Solenoid systems are much easier to dial in initially, but have some downsides, like hammer,noise, etc.

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During steady state operation (collecting hearts for example) we maintain about 1 to 2 tenths of a degree variation, it holds pretty rock solid.

We see a little bit more variation running in 100% reflux at startup, but it's usually less than plus or minus one degree.  I chalk this up to the valve having a little bit less control when it's opened wider.  It's typically in 3/4 open during this, versus 1/4 open during hearts collection (higher dephleg temp).

Setpoint changes are a little bit slower, taking about 5 minutes before all oscillations are damped, but we never usually see more than 1 degree of overshoot.  We can dial in faster responsiveness with the PID, but it's at the expense of larger overshoot.  With the slower response, it's more of an "ease-in" to the new setting.

I would look at your controller settings if your oscillation is high, it took us quite a bit of time to dial-in settings so that we weren't dealing with a system that went crazy with temp swings and oscillation on my input change (change of steam pressure, for example).

We're really liking this, as it can respond to huge increases in our reservoir temp over the course of a run, at least +20-30F.  You would never know it based on the setpoints/controls.  In a manual valve situation, you would be constantly adjusting the valve to keep a steady setpoint.

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4 hours ago, Silk City Distillers said:

Hell, give it a try, especially if it's working well.  Something like a Watts LF150A?

 

 

Yup, that's exactly what I had in mind. Supplyhouse.com has them for about $30.

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29 minutes ago, Silk City Distillers said:

I wish Supplyhouse was around when I was remodeling my house, that place is spectacular.

I cant say enough good things about them.  Plumbed most of the distillery and my entire garage/brewery/distillery/man cave with their parts and support.

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3 hours ago, ArtisanGrain said:

The controller part is easy. the perfect controller is available from Automation direct, and may be found here: https://www.automationdirect.com/adc/Shopping/Catalog/Process_Control_-a-_Measurement/Temperature_-z-_Process_Controllers/1-z-16_DIN_Size_(SL4848_Series)/SL4848-CR

 

really want to write the control software myself but for $100 (plus RTD) I simply cant justify it. Thanks for the link. 

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Buy this instead, same price.

http://www.ebay.com/itm/Temperature-process-PID-OMEGA-CNi16D53-Ei-1-16-DUAL-DISPLAY-CONTROLLER-/162219520896?hash=item25c5097380:g:lrwAAOSw~gRVsF-

Ethernet for remote monitoring and data logging.

Omega CNi16D53 (this specific model) - has proportional output AND a relay output for whatever other function you want.

Or this one, I'm not sure if the other one has the panel mount bracket:

http://www.ebay.com/itm/OMEGA-CNI16D53-EL-TEMPERATURE-CONTROLLER-90-240VAC-50-400HZ-5W-/171745734644?hash=item27fcd7eff4:g:Bo8AAOSwymxVIr7S

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Thanks to everyone here I picked up a LRQB24-MFT Belimo high speed actuator off of eBay for around $75 shipped. Need to head over to supplyhouse.com for a valve body and then to automation direct for the controller + other bits and bobs to complete this project.

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Be really careful about your valve body selection on municipal - especially considering supply pressure is going to have a big say in this equation, as well as your input water temperature.

You can use a manual valve to throttle back some flow if you find that you have extremely cold water, very high pressure, etc - but this isn't really ideal compared to sizing correctly.

What's your dephlegmator flow rate look like today?  Input temp, output temp, gallons per minute?

 

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Re: muni supply -- that's a huge problem for us.  If someone is in the crapper or washing dishes our flow really drops which results in a predicable drop in ABV. Also groundwater temp -- mid 50s in the winter, low 70s in the summer. Chiller & reservoir are in our near-term future.

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  • 9 months later...

Tossing this out for anyone that may be interested. I may use some products from these guys to replace some Johnson Controls motorized ball valves. Faster, and more linear range.

http://www.hassmfg.com/search.pl/1244582085-65969?keyword=1161&submit=Search

Specifically, I had a situation where the process dynamics were about the same speed as the Johnson Controls valve, and it became unstable with any aggressive PID tuning. I achieved acceptable performance using feed forward with PID, but a faster valve is really the best solution.

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Hey guys. There's also such a thing as a slow opening/closing solenoid valve. Works just the same way as a normal solenoid valve, but doesn't crash open and closed. I learned about them, of course, AFTER putting in a bunch of the fast acting ones.

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For you guys on municipal water, a cheap surge tank and regulator does wonders to smooth out cooling supply and prevent sudden oscillation when someone flushes a toilet. It won't help cool in the summer, but you can tweak your regulator settings and it will mitigate that a bit. Last place I did this on had input at 85 psi, 150 gallon steel surge tank, output at 55 psi. Some people use bladder tanks (like on an RO system or hot water tank) with a check valve on the input to regulate water supply as well.

The "slow" solenoids are nice at first, but the ones I've used (from Asco and from DUDI) heat up really quickly and need rebuilding a lot. I prefer a pneumatic proportional valve for high volume dephlegs.

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