Lime Valve

[glowing]

hello, I am in the midst of looking for a new lime addition valve. We currently have a pnumatic system, with a solenoid being energized/de-energized at given time intervals. The Lime is in liquid form, and flows into an open tank via a 1" line with a pinch valve.

We would like to get rid of this loop, as it is the only air operated system in the building, and we have had some freezing problems (way up north here, and our process remains mostly indoors, so we do not have a nearby air dryer).

We desire to put in an electric driven valve, but, it MUST be fail-closed. Thought of using a solenoid with 1" ports, and flowing directly through it, but fear it will be gummed up. Would LOVE to find an electronic, fail closed pinch valve if such a thing exists. Realise that I will likely have to get a rotating valve though, and that sliding stem is not a good option.

thanks for any feedback...Glowing

 

[JimCasey]

Worcester makes a fail-closed electric actuator: Model 72. Coupled with one of their ball valves with abrasion-resistant Ultra-high molecular weight polyethylene (UMPE) seats, and you should be covered.

Install with the stem horizontal and the actuator on the left when looking downstream so the rotation of the ball initially does not drag rhe settled grit into the seats. Horizontal shaft also makes it easier to see the travel indicator, too.

 

[obsy]

Hi 'glowing',

I have basically the same setup as you (lime slurry, 1" pinch valve, actuated, on/off operation) but instead of the probelem being the actuation, it's the pinch valve sleeve being corroded to quickly and failing too soon.

I'm trying to extend the life of the sleeve.

Have you done research into the best material and design of the sleeve?

Any guidance would be greatly appreciated.

Thanks
Mark O

 

[glowing]

hmm, I have worked at a few plants with lime addition, and never had big problems with the sleeves. here, they are lasting a minimum of 8 months. I shall check into what we use and get back to you, but your lime might be the issue.

BTW, fisher has a valve, but it is going to be around 13000, so I am thinking of just using a failsafe nuematic. This was my choice, but the head ops have it stuck in their minds that it needs to be electric (they are a bit weary as the fail open valve dumped all the lime 3 times in 1 week during power outages....a major headache, and fairly costly.) Barber also came up with a valve they think will work, but it is not a pinch valve, so I am not so sure.

 

[glowing]

obsy, what make of valves are you using. we use redvalve 2500s, with stoch sleeves. We do have some straight through sleeves, and some coned. The coned do seem to hold up a lot better.

 

[glowing]

obsy, what make of valves are you using. we use mainly redvalve 2500s, with stock sleeves. We do have some straight through sleeves, and some coned. The coned do seem to hold up a lot better.