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Ted Mooney, P.E. RET
Pine Beach, NJ
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for Metal Finishing since 1989
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Vapor Degreaser Acid Inhibitor Needed
Q. I am looking for an acid inhibitor package to add to our perchloroethylene vapor degreasers. We conduct weekly acid acceptance tests on our degreasers and if the acid acceptance is low we would like to add/replace the inhibitor rather than dump, clean and neutralize, and recharge.
Any one with info or can point me in the right direction?
Greg H [last name deleted for privacy by Editor]helicopters - Fort Worth, Texas
1998
A. Hi Greg,
The perc manufacturer is the only one that can help you out on that one and they are reluctant for two reasons:
1. they sell more product this way.
2. the acid acceptance goody is hazardous and normally a mixture of at least a couple of items. Nitro methane is one that is common in trichloroethane. Imagine their liability when some fool adds this to a hot tank, it vaporizes so rapidly that the cooling system can not contain it and a spark ignites it with a massive explosion. They also know that the average shop will overdose the tank and then bitch when it does not work right.
The solution is to keep out the water or other material that is causing the problem. Perc is not bothered by MINOR amounts of water, so what else is going into the tank?
The poor lab tech is always blamed. It is a production problem and only they can solve it and they normally have no desire to since that would get in their road.
I caught workers drying parts on the night shift. Also found parts with very blind cavities that still had plating solution in them going into the degreaser.
Unless you are in control, lots of luck.
James Watts- Navarre, Florida
A. Hello Greg,
Trichloroethane was outlawed for use in the US several years ago. Today you can use trichloroethylene or perchloroethylene. Both of these solvents are explosion and fire proof.
In the past we used trichloroethylene and purchased the stabilizer for the solvent from the manufacturer. The stabilizer and the solvent were PPG products. We purchased the stabilizer by the 55 gallon drum and exported the chemical to Mexico to support our process. I purchased two drums a year. We conducted weekly acid acceptance tests also and after we started using the stabilizer we saved a great deal of money.
We have not used vapor degreasing for several years but contact Finishing Equipment Inc., St. Paul, MN about your process and ask for their help in locating a source for your stabilizer.
I hope this helps.
Joe
- Taicang, China
June 18, 2008
Q. Any recommendations on known and tried acid acceptors/metal stabilizers for trike? Purpose is to extend sump life in vapour degreasing operations.
Also wanted to know if there are any standard tests for checking oil buildup in the TCE solution? Know spectrography can be used but want something easier & feasible for operators..
AAV(acid acceptance value) can be done but do not have much details about it.
- Ahmedabad, Gujarat, India
August 9, 2012
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