Recommendation for valve and flowmeter

[CoryPad]

We conduct corrosion testing. My corrosion chamber uses a salt solution prepared from deionized water. A 0.75 inch inner diameter city water pipe feeds into a reverse osmosis (RO) unit (Millipore RiOs 200):

http://www.millipore.com/catalogue.nsf/docs/C8674)

The RO unit fills a 60 l holding tank (Millipore):

http://www.millipore.com/catalogue.nsf/docs/C1834

The 60 l tank outlet is connected via a 0.375 inch inner diameter plastic tube to a diaphragm pump (ShurFlo 8000 series):

http://www.shurflo.com/pages/new_industrial/industrial/automotive/doc_sum/8000-813-238.html

The outlet of the pump is a 0.375 inch inner diameter plastic tube into a user-switched solenoid, which then feeds a 5000 l solution tank with an overfill limit switch tied into the solenoid.

Since the pump feeds at 6 l/min (1.4 gallons/min), but the RO unit only produces at 3.3 l/min, a user must repeatedly switch the solenoid open/closed to fill the 5000 l tank to avoid running the pump and 60 l tank dry.

Our desire is to match the flow rate through the pump with that from the RO unit so that the filling operation can be done without human intervention. I would like a recommendation for a valve and flowmeter (preferably one that reads in liters per time) that can be inserted between the pump and the 5000 l tank that will do this. I believe a simple hand-operated ball valve and a simple acrylic-bodied rotameter would work, but I have no expertise in this area. Cost is a concern: < US$1000 is almost mandatory, and < US$100 is desirable. I am located in the USA, so that may limit suppliers.

Thank you for your help.


Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

 

[Ashereng]

Yes, that should work.

If you want easier/better control, perhaps a hand operated needle valve?

Acrylic bodied rotamter is also good. You didn't mention pressure so I guess acrylic is okay.

Under $100 US, maybe. Under $1000 US, should be easy. Contact your local supplier - these are very common commodity items you are mentioning.



"Do not worry about your problems with mathematics, I assure you mine are far greater."
Albert Einstein
Have you read FAQ731-376 to make the best use of Eng-Tips Forums?

 

[dbaird]

Check with:

http://www.omega.com/

http://www.coleparmer.com/index.asp?index=home

http://www.harringtonplastics.com/

They handle applications/products like this every day.

David Baird

Sr Controls Designer
EET degree.
Journeyman Electrician.

 

[CoryPad]

I didn't mention pressure, partly because I am confused about what pressure is created by the pump. It is listed as having a 100 psi demand switch, which I believe means it automatically shuts off at 100 psi line pressure. I suppose that means my flowmeter needs to withstand that, which probably rules out an acrylic rotameter. I suppose I will call Omega, though I will continue to take suggestions from here. Thanks.

Regards,

Cory

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.