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Chemicals in Aqeous Cleaners

Dreamsniper

#28178

Chemicals in Aqeous Cleaners | 21 April, 2004

Now the ball starts rolling. I'm lookin' for a new aqeous cleaner. Do I really need chemical cleaners or saponifiers, surfactant etc. for an Aqeous Cleaning Machine in removing OA or Water Soluble flux from under my 1.27mm Pitch BGA down to 1mm Pitch BGA? Is a Mid-size Wash-Clean-Dry Cleaner be enough for them to be removed?

What is Water Treatment for?

Thanks and regards, Dreamy

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#28182

Chemicals in Aqeous Cleaners | 21 April, 2004

Dreamy

"Ball rolling"? Are you a bowler? My nephew does the audio for the ESPN2 production of the professional bowling tour.

Search the fine SMTnet Archives for discussion on assessing cleaning machines. For instance: http://www.smtnet.com/forums/Index.cfm?CFApp=1&Message_ID=27332

Water treatment has multiple purposes: * Deionized water removes the ionic residues from OA fluxes better than untreated water. * When you get water dirty [during the cleaning of your product], you use water treatment to clean the waste water up and leave it cleaner than you found it. Simple as that. Look here: http://www.wastewaterpro.com/links.html

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#28208

Chemicals in Aqeous Cleaners | 23 April, 2004

Adding a Chemistry will reduce density of solution to get under the devices more effectively. You can clean your OA flux residues well enough with just hot water and hot DI water rinse. Top batch cleaners: http://www.speedlinetech.com/electrovert/aquajet.aspx http://www.aqueoustech.com/ http://www.aat-corp.com/ http://www.emcgti.com/products/product_view.php?id=180&return_url=

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#28209

Chemicals in Aqeous Cleaners | 23 April, 2004

Waste Water from any cleaner must be recycled or treated before going to drain. That is the case in most states in the USA. The wash solution that is mixed with a chemistry cannot be processed thru a water recycling system, only the rinse water can. Spent wash solutions must be "treated" to neutralize the chemical and lower the PH. Only then can it go down the drain. That is referred to as a "treatment to drain" process. You also have the option to have spent wash solution hauled away as toxic waste in 55 gal drums.

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Ron Herbert

#28217

Chemicals in Aqeous Cleaners | 23 April, 2004

Dreamy,

Adding chemistry to the wash section in a cleaner does have its advantages. It reduces the surface tension of the liquid and will remove contaminates such as fingerprints.

It does however complicate the process in respect to water treatment.

Normally there will be an isolation section after the wash section which helps in keeping as much chemistry in the wash section as possible. This isolation section normally consists of an air blowoff, a water rinse, and another air blowoff. This rinse water cannot be sent to a water reclaimation unit since it has too much chemistry in it. It therefore must go to drain.

In a water only, cascading system, all water sent to the cleaner can be recycled. This not only saves water, but also saves the heat that has been put into the water. It also makes it easier to have hot water coming into the final rinse which makes drying easier.

Just a note: if you are using a water soluble solder mask and are going to recycle the water. the mask must be clay free. Clay will gum up DI beds in a flash.

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