XPOST: My idea for a DIY actuated ball valve (for wave makin

[jsilver]

This is a cross-post with the DIY forum.
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Hi everyone... this is my first post in these groups and I hope it gets some replies. It's a long post but please hang on! I'm in the planning stages of a reef tank and am looking into ways to make some current in my future aquarium. I know about surge tanks, those rotating heads you can put on pump returns and a cycling powerheads on and off. I don't like moving parts IN my aquarium, so the best thing I've found is the idea of a closed loop with an actuated 3-way ball valve on a timer. The rest of my idea relies on you already understanding this concept

What I like about that system is that it uses one external pump that's always on (not cycling) and that the water is being pushed from one side of the tank to the other instead of sea swirls, for example, which kind of change the flow direction but don't really make much cross-tank disturbances. The problem with these actuated ball valves is that they're over $300 and they're slightly less than ideal since they have duty cycle of around 25% so the flow of water can only change outlet maybe once every minute. So my DIY idea for a actuated ball valve is as follows:

Buy a Plast-o-matic 3-way manual ball valve (with the 3 hole ball so that the flow of current is never fully restricted). The 1" version has a 45 lb/in rating which is the amount of force necessary to turn the valve. The valve itself probably runs around $60 or $70. Buy a geared AC motor. The model I found is from McMaster/Carr and turns at 3rpm, draws 0.4 amp, puts out 50 lb/in of torque, and costs $33.40. Build some kind of small platform that will mount the valve to the motor so that the motor essentially turns the valve for you. I would have to dremel out the little plastic flanges on the valve so that the valve can turn 360 degrees rather than just 180. The benefits here (other than the total cost of just over $100 instead of over $300 is that this motor is rated for continuous duty so it could be turning the valve all day long. That means that every 10 seconds the water is slowly rerouted from one outlet to another and then the next 10 seconds, it's rerouted back... all gently, all with one motor, and it's continuous, like real ocean current. The $300 actuated valves are so expensive, in part, because they have to have sensors in there that know when the valve has reached it's stop but we don't even want that. I'd rather have the flow go from one outlet to another slowly and constantly than stop for a few minutes. There's also a 1 rpm version of this geared motor, by he way, if you think you'd rather have it take 30 seconds to reroute the flow than just 10 seconds.

So is this doable? Am I forgetting something?
The only thing I can see as being a problem (other than mounting the motor to a small frame with the valve) is that the holes in the ball in the valve might only be oriented so that you get continuous flow between the original 180 degrees of movement and not through the modified full 360. Perhaps I'd have to drill another hole in the ball.

Comments, suggestions? Did this make any sense to anyone!?

 

[AnotherGoldenTeapot]

Well it's definetly possible to build a DIY actuated valve - at least for use on a solar heating controller for a swimming pool.

My father built one using a windshield wiper motor, a few gears, couple of micro-switches etc.

Had it been me I would have just gone and bought an actuated valve - I know they're really expensive but it would work without 200 hours of effort

Nosie from the motors might be an issue - especially if they are operating every ten seconds. I bet the valve will wear out too - I can't imagine they're even rated for 3 million operations, and you'd do more than that in a year. I hate to imagine how they fail too - would not want them starting to leak...

I personally prefer the idea of using triacs to turn powerheads on and off. One day I'll get for the "like the idea" to the "building" stage.

 

[Anonymous]

hi.

PlastOMatic ball valve has a machined ball, and if you drill a hole in it, you can ruin it. You can replace the ball, but you need special tool to take the ball out. On a brighter side, the plastomatic ball value is desiged for full 360 rotation, so you will be fine without any modification.

Your plan is doable. Making mounting bracket for valve/actuator pair is commonly done. But I don't see why you want to change the flow direction 6 times per minutes... Besides, as it was pointed out, the noise and wear and tear on the motor/valve is something you have to consider. Changing the flow direction too often wastes energy since the start of each change is working against the remain flow before a nice flow is establised. For application that needs high CPM rate, people in the industry don't usually use ball values.

(I have some left over actuated ball valves in the market place really cheap, but only one set was sold...)

 

[jsilver]

Thanks for the comments so far guys... here's some comments...

>>Had it been me I would have just gone and bought an actuated valve - I know they're really expensive but it would work without 200 hours of effort .

Yeah, I know how you feel!

This project should take maybe 10 hours at most, and honestly I don't like the motion of the actuated valves. I want continuous change, not just a change every few minutes which seems rather unnatural to me.

>>Noise from the motors might be an issue - especially if they are operating every ten seconds.

You're absolutely right, although I've heard the "real" actuated valves are rather loud anyway. Also, just to make sure we're on the same page, my motors don't run every 10 seconds... they run continuously (and are rated to do so)

>>I bet the valve will wear out too - I can't imagine they're even rated for 3 million operations and you'd do more than that in a year. I hate to imagine how they fail too - would not want them starting to leak...

Well, they're rated for 1M operations. So lets take the case of the 1RPM motor. So that's 2880 individual turns day, which is about 1M operations a year. So yes, the valve would wear out after that. It's a sealed valve (I've been told), however, so I think the ball would just start to wear down... I doubt the whole thing would just split open and blow up... but excellent points!

>>I personally prefer the idea of using triacs to turn powerheads on and off. One day I'll get for the "like the idea" to the "building" stage.

Yes, but many people here have had experiences with Powerheads blowing up and frying their tanks or leaving toxic debris in the water... that seems less than apealing to me.... not to mention the fact that turning pumps on and off is hardly a natural water flow... but all this is obviously
just my opinion!

>>On a brighter side, the plastomatic ball value is desiged for full 360 rotation, so you will be fine without any modification.

That's great news!

>>But I don't see why you want to change the flow direction 6 times per minutes...

Well, I want natural water flow, which if I remember from my diving years is fairly rapid and sinusoidal. But I think the 1RPM motor is more realistic which means it takes a full 30 seconds to change the flow, which is nice and slow...

>>Besides, as it was pointed out, the noise and wear and tear on the motor/valve is something you have to consider.

Yes, good points both...

>>Changing the flow direction too often wastes energy since the start of each change is working against the remain flow before a nice flow is establised.

True, again. For my applications, this may be okay, though, since I would have a comparably small tank and wouldn't need THAT much wave flow anyway.

>>(I have some left over actuated ball valves in the market place really cheap, but only one set was sold...)

What "marketplace" ?

Thanks again, guys...

 

[Anonymous]

Reef Keeper MarketPlace

 

[valid]

i believe spears brand electrically activated 3way ball is rated at 75% (rather than 25%) duty cycle, if that helps.