Connecting 3-Way Valves In Series

How about a sketch of your layout? Do you have your fill level gauges picked out? How big of a pipe will you be using? What is the maximum pressure? Is your fluid abrasive or caustic?

If you can provide this kind of information, you are more likely to get a suitable answer to your question.

What I read here is the important thing is the level gage will open and close the valve.

I'd do two three way valves and one two way (on/off) Here goes, see if you follow me.

Pipe from source to on/off (A) valve to first three way valve (B) tee to tank 1 and continue to three way valve (C) tee to tank 2 and continue to tank 3.

instead of a level gage, can you use a float valve?

Now start to start with, when float valve in tank 1 is open, it closes valve C and opens valve A (main shut off) and B.(valve to tank 1)

2. When float valve in tank 1 is closed, it closes valve B.

3. When float valve in tank 2 is open, it opens valve C, only if tank 1 float is closed.

4. When float valve in tank 2 is closed, it closes valve C only.

5. When float valve in tank 3 is open, it does nothing...

6. When float valve in tank 3 is closed, it closes main valve A.

hope that helps

laby

Puzzling. Sketch please. A good application and i'm very interested.

You mentioned about three way valves connected in series. Why did you put this restriction?

Depending on your pipe size and requirements, 3 shutoff valves and some small sized contactors would do a great job and would be inexpensive.

Give us some details about your fluid and pipes so we can recommend some brand, size, etc. Are you thinking about electrical actuation, electrical control and pneumatic or hydraulic actuation, or what?

Hi bhrescobar,

You mentioned about three way valves connected in series. Why did you put this restriction?

I think the OP may have meant "in sequence"; fill first tank till full, then switch to filling second tank, etc.

You're right, OP needs to give more details as you have outlined.

Mike

thanks so far for all your reply

yes you got it right,but after the last tank there will be a return line to the source tank

the pipe size is 2"

the fluid is semi solid(high viscous materials)eg jam

Hello O blessedman,

Is this the basic setup you had in mind?

Let me know - we can use this as a starting point.

Mike

Thanks master for your input. Now I realize it. However, powerfull the dark side is... and maybe I could find a way to cheat the death...

Three-way valves tend to be expensive, and I don't see the need for them here.

Consider running a feed pipe by all three tanks, branching off a simple solenoid valve to each tank. Equip each tank with a float switch having both normally closed and normally open (SPDT) contacts. Wire the NC contact of each switch to the respective solenoid valve feeding that tank. Wire the NO contact of the first float switch to the common (C) contact of the second, and likewise the second to the third.

If you are using a pump to supply the common feed line, use the NO contact of the third float switch to power a relay, with an NC contact in the pump circuit. (When the third tank is full, this shuts off the pump.)

Very straightforward, unless some as yet unmentioned issue requires a more complex arrangement.

Is there some reason why an ordinary float valve connected to a branch line to each tank will not be sufficient? This combines sensing and control in one low cost valve, which can be configured for various fluids and temperatures with some limitation on supply pressure.

Bioramani

PLC/Relays?? Straight pneumatic?? How big are the tanks???

the issue here is that the temperature of the product has to be maintained constant along the line, therefore the need for the return line,that returns to a pasteurizer

2000 litres each

pneumatic valves

I would still look for shutoff valves commanded by level switches in a really simple control system. Three way valves are much more expensive and it seems that you do not need them here. Just add tees to the supply line and make it recirculate while bleeding one valve at a time for each tank as required.