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Level control for heated cleaning tanks

What is a good method for controlling the volume in cleaner tanks in a barrel plating line? The level drops past the probes for feeding the cleaner and turns on the feeder unnecessarily. There is no room for separate overflow tank, & the barrels entering and leaving the bath change the volume by about 4 inches.

Mike McDonald
mack products - Jefferson, Wisconsin
1998

Mack:

Most cleaners operate quite hot and evaporation is a big factor. It is water, not liquid cleaner, that should be added with your level control probes! Put a barrel in the tank, and manually get the level where you want it. Then pull the barrel out, and set the probe so it will add water when the solution drops below this level.

As for the liquid cleaner, feed that in based on hours, amp-hours, or barrel loads--not solution level.

Ted Mooney, P.E.
Striving to live Aloha
finishing.com - Pine Beach, New Jersey
1997

Thanks for your reply, Ted. My cleaners are controlled by conductivity probes, and it is the level of the solution that needs to be controlled. Evaporation draws the solution level down so far that the probes are exposed. I have extended the probes in one installation, but the platers just let the level fall below the middle of the barrels. The information I need is for some kind of valve or something I can install and depend on to keep the level up.

Mike McDonald
mack products - Jefferson, Wisconsin
1997

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One of the most efficient setups for automatic barrel plating is a cleaner tank with an overflow weir about 4-6 inches wide on one end.

A recirculation pump can be fed from the bottom of the weir to the top of the cleaner solution on the other end of the tank. Clayton Valve Company, based in Canada, manufactures an excellent float type automatic water valve utilizing a pressure diaphragm cut off valve. This valve can be placed in the top of the weir to regulate water level.

Phil Pace
- Tulsa, Oklahoma
1997

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1997

If I read you letter right, you do not have room for on overflow tank.

Protherm in Orange,CA makes a very nice electronic probe sensor that is wired to a makeup water source solonoid valve.

A rehash of Ted's comment:
Put a loaded barrel in the tank and get the level exactly where you want it.
When the barrel comes out, install the probe 1/4 inch below the new liquid level.
As soon as the middle length probe is exposed, the water will turn on. It will shut off as soon as it makes contact with the shortest probe. These are cut to length by your people.
Others make similar devices but are not as neat in my opinion.

James Watts
- Navarre, Florida

Thanks for your help, guys, and I'll be using the probe method. Again, thanks for your time. Mike.

Mike McDonald
mack products - Jefferson, Wisconsin
1997

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Q. Hello Srs,

I need your advise about the best way to control the auto filling system for anodize line tanks. We currently use a floats system but its not perfect and sometimes it fails. What kind of sensors can we use to control the level of the solutions?

Yohands Rey
Engineer - Mexico
April 2, 2012