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Cleaning process for electroplating

How to measure or monitor the cleaning performance? We use caustic media with some kind of additive. Is that possible to get high alkalinity with low pH in cleaning solution? 'Cause our cleaning sol have very high pH level(12-14) and we afraid that it will etch on parts and forming the metal sludge.

K.Robin
- Thailand
2005

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First of two simultaneous responses --

What kind of parts are you cleaning first off? How long of a cleaning time do they get? What is the additive that you put in the cleaner? Now I could tell you that any cleaner that I have dealt with in my 15 years of experience has had a very high pH at least 10 or higher,you could lower down the pH a bit to suit your needs but will it clean as well? Also what temperature are you cleaning at? I feel we need a bit more info from you.

Regards,

Brian C. Gaylets
McKinney Mfg. Assa Abloy America - Scranton, Pennsylvania
2005

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Second of two simultaneous responses --

Robin,

Your query is not clear. What is the metal you are using? And Alkalinity is measured on the basis of pH. Higher the pH, higher the alkalinity.

Keshava Prasad M
- Chennai, India
2005

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2005

I apologize for the unclear question. For more information, the cleaning part is steel and the additive is 613-HX ,the commercial name which I do not know exactly what is it.
About the cleaning condition,we control [NaOH] to 50-60 g/L and control temperature to about 80 C. The steel will be soaked in solution 5 sec.Now we just control only these parameters so we need something indicate the cleaning performance or cleaning bath life.

Best regard,

K.Robin
- Thailand

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First of two simultaneous responses --

First, if you want to monitor cleaner performance, you need to know what it is you are trying to clean off your parts.

A general (and very subjective) measure of cleaner performance is a water break test (and I am not going to define it; do a web search).

James Totter, CEF
- Tallahassee, Florida
2005

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Second of two simultaneous responses -- 2005

The cleaner is probably a high pH cleaner with some wetter added and a few other additives,thrown in for good measure. If you are not sending any current into this tank,leave the part soak for longer than 5 seconds,that maybe a lot of your problem. Do you back titrate the cleaners to see if they are in the percentage where you want them at? There is no real way to say how long a cleaner will last,there are a lot of factors you have to figure in the scenario.


Regards,

Brian C. Gaylets
lock mfgr. - Scranton, Pennsylvania

First, you can check and keep concentration of NaOH in control range follow your product data sheet everyday if you operated 24 hrs.and you check appearance of your parts after cleaning process it's OK or not(watermark and other dirty defect must not see) and if you can add preclean process(use recycle solution from cleaning bath or hot water spray) before cleaning bath it can reduce load of oil and contaminate for cleaning process.

Wongwannarak P.
- Bangkok, Thailand
February 9, 2010