Comments on: Solenoid valves for brewing

By: Trinity Cywinski

Trinity Cywinski — Tue, 12 Jul 2011 04:02:57 +0000

I’m not sure where you are getting your information, but good topic. I needs to spend some time learning much more or understanding more. Thanks for wonderful info I was looking for this information for my mission. Trinity Cywinski

By: piper

piper — Thu, 29 Jul 2010 20:27:38 +0000

You have to be careful with most solenoid valves you find.

For one thing, just because it has 1/2″ NPT connections doesn’t mean it’s 1/2″ all the way through.

Second, most of the affordable valves are “pilot-operated” valves. That means the solenoid doesn’t actually actuate the main valve. It just actuates a very small pilot valve, which opens to allow a small pilot flow from the inlet, and the inlet pressure itself operates the main valve. http://en.wikipedia.org/wiki/Solenoid_valve

Piloted solenoid valves have two potential problems for our purposes. First, the channels for the pilot flow can be very small and may be clogged by bits of grain. Second, if the inlet pressure is not high enough, they will fail to operate. They may fail to open, or they may fail to close.

By: Great idea

Great idea — Thu, 29 Jul 2010 20:15:58 +0000

I am engineering in my head a computer-controlled home brewery as well. I do plan to use 1/2″ ID silicon hose.

I was looking at some 35$ brass solenoid valves 1/2″ NPT on ebay.

As it happens, I have 6 large hi-torque servos (for 1/4 scale RC airplanes). They are PWM controlled, an easy task for a hobby microprocessor. I’m sure I can rig them to pinch silicon hose.

Thanks for the idea!!!

By: piper

piper — Thu, 08 Jan 2009 01:36:28 +0000

I thought about both ideas. Ball valves can be very stiff sometimes. To open a ball valve, you’ll need either a huge force, or a really long stroke, depending on how far out the lever you connect the solenoid. Also, to close the ball valve, you’ll need either a stiff spring (which would increase the force requirements of the opening solenoid), or another solenoid.

For every bit of mechanical advantage you get from a lever, you need a correspondingly longer stroke.

You can buy electrically-actuated ball valves (very expensive). I think they all use a motor, not a solenoid. Probably with a lot of gear reduction, I’d guess a worm-and-wheel gear, since they give a large torque multiplication in a small package.

It would be interesting to try to prototype an actuated ball valve using a small motor and a recycled guitar tuning peg.

By: Rob

Rob — Wed, 07 Jan 2009 05:34:01 +0000

Have you considered using the solenoid to actually swing a lever on a ‘normal’ valve (1/4 turn ball)? How about using the solenoid to work a lever that does the pinching, thereby generating a mechanical advantage? Just a couple thoughts… You have a great site and are very creative, just trying to help you see it from another angle. – Rob

By: Nate

Nate — Wed, 08 Oct 2008 02:29:47 +0000

Try looking at industrial controlled propane vales, I am using them to control , the fire , but they come in many styles, we use PE or PTFE pipe in the propane industry.

By: Jones

Jones — Sat, 21 Jun 2008 22:12:44 +0000

What about PTFE or Nalgene valves used for science equipment… they’re chemcial resistant and temperature tested. They also have hoze barbs and other features built in.

By: Jones

Jones — Sat, 21 Jun 2008 22:09:15 +0000

My thought would be to use a DC motor and worm gear to tighten a screw that pinches the hoze… much like the pinch-clamps that are screw driven (I can send you some). DC motors are dirt cheap. Worm gears are also very cheap (Princess auto!). Also, instead of pinching the hoze between a V and a Nothch, try looping the hose through the pinch mechanism so that it pinches the neck of the loop rather than just the walls of one segment of the hose.

P.S. If you want something milled or turned, drop me a line. I’m getting good with stainless.