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Batch Cleaners

gpaelmo

#26099

Batch Cleaners | 17 October, 2003

We have a need to clean boards. Can we use a regular dishwasher if we feed it with DI water thru a water heater? What kind of issues can come up with doing it this way as opposed to an industrial type batch cleaner? Any thoughts or comment would be appreciated.

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RDR

#26101

Batch Cleaners | 17 October, 2003

Most batch cleaners are "dishwashers" with stainless steel pipes and cabinets. Heated DI water is a good thing. Are you cleaning Watersolubles or no-cleans? You will need some chemistries for the No-Clean and the W.S. will eventually eat through all the pipes and such unless they are stainless steel. You will also need to test for cleanliness since you cannor be sure of the amount of "shadowing that will occur in this unit. Where will your waste water be going?

Russ

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gpaelmo

#26102

Batch Cleaners | 17 October, 2003

we will be using water soluble solder paste. cleaning will be for smt assemblies only. waste water will be treated prior to disposal. as far as testing for cleanliness, any suggestions or recommendations on test equipment would be greatly appreciated. we will only clean boards on this one product line (with RF circuitry).

Thanks Again

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Mike Konrad

#26106

Batch Cleaners | 17 October, 2003

First, I should state that my company manufacturers batch and inline de-fluxing systems. Because we manufacture both formats, we remain unbiased. In fact, it is in our best interest to recommend inline cleaners since they sell for considerably more than a batch system.

Russ is partially correct. Some batch cleaners are basically dishwashers with elaborate controllers. Others, however, are sophisticated, high pressure cleaning de-fluxing systems.

Specifics on batch-format de-fluxing systems vary from brand to brand but here are some highlights.

Many batch machines lack the pressure, spray diffusion pattern, and quantity of nozzles to provide effective de-fluxing. When selecting a batch machine, I would recommend a minimum spray pressure of 60 PSI. Batch machines are available with spray pressures from 10 � 110 PSI (brand and model dependent).

The type, quantity, and location of spray nozzles are also important. Nozzles that produce a fine diffusion pattern are better at under component penetration (impingement) than course (dishwasher) nozzles. Ensure that there are adequate quantities of nozzles to ensure thorough, overlapping, coverage. A four-sided spray system (nozzles located above, below and on both sides of a board rack) will reduce or eliminate shadowing.

As Russ pointed out, the removal of no-clean flux requires the use of a chemical additive. As chemicals are not free, I would recommend that you choose a cleaning system that captures, filters, and reuses its wash solution. This will reduce the volume of effluent and the cost of chemicals. Many manufacturers provide this configuration.

As many batch machines are equipped with a filtration system, most users simply direct the effluent to drain. In areas where discharge is prohibited or undesirable, an evaporator may be used to allow the cleaning system to operate in a zero-discharge configuration.

Check with the various batch cleaner manufacturers for specific configurations and details. They include:

Aqueous Technologies http://www.aqueoustech.com

EMC http://www.emcgti.com

Austin American Technology http://www.aat-corp.com

UnitDesign http://www.unitdesign.com

Cookson / Speedline http://www.speedlinetechnologies.com

I hope this helps!

Mike Konrad www.aqueoustech.com konrad@aqueoustech.com

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