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Saponifier Concentration Measurement

#18327

Saponifier Concentration Measurement | 3 December, 2001

How do yall monitor the concentration of yer saponifier?

[NOTE: This is a BIG chance for NC flux-types to make smart remarks in retribution for remarks made about removing solder balls in an aqueous cleaner.]

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Brian C

#18333

Saponifier Concentration Measurement | 4 December, 2001

We use a Hach digital titrator. You can buy a digital titrator kit, hydrochloric acid, phenolphthalein indicator powder pillows, turkey baseter (or some bulbus sucking device) and a couple small measuring cups. We do tests twice per shift (more is overkill) and try to maintain a concentraion of 4%. The kit comes with a manual that is real fun to read and figure out....snicker snicker. Good luck.

Try http://www.hach.com

Brian

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#18338

Saponifier Concentration Measurement | 5 December, 2001

Another measurement tool is a refractometer to measure light refraction. The saponifier will have a specific refraction property is measure agianst an index.

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Michael Parker

#18343

Saponifier Concentration Measurement | 5 December, 2001

I like the idea of a bulbous sucking device - can I get one with large cups instead of small?

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CAL

#18344

Saponifier Concentration Measurement | 5 December, 2001

I concur with Pete. We use a refractometer to measure soponifier concentration.It is simple fast and straight forward.

Cal

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Scott B

#21318

Saponifier Concentration Measurement | 26 August, 2002

We have inherited the need to monitor saponifier concentration and would like to avoid the need to perform titration testing and would obviously like to introduce continuous monitoring if possible.

Is refraction commonly used as a measurement method. Does it provide adequate resolution. Is the measurement affected significantly by any factor common within the process. Can anyone recommend instrumentation for continuous monitoring of concentration levels using refraction.

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dragonslayr

#21321

Saponifier Concentration Measurement | 26 August, 2002

Scott- I've used both methods, titration and refractometer. Both are simple to perform. Titration is a simple, high school science class type process. Follow the chemical mixes accurately and then compare the resulting color change of liquid to a chart that gives you an answer. Being +/- 5 % will not be a big issue. Consider the overall volume of saponifier in your DI water. If your are runniing with 10% saponifier and the test results are off by 5 %, you could be measuring in the range of 9.5% to 10.5% overall concentration.

Refractometers are very simple to use, just put a drop of liquid onto a glass window and read the results. Once again, matching a color to a chart to determine your reading.

Automated gadgets a very nice, but may be impractical in expense with regards to the simple ways previously mentioned.

Look for a Scientific Supply catalog such as Fischer Scientific, Baxter, etc. Catalogs will also give you basic theory and operations instructions for these methods. Also, I've seen refractometers at auto supply houses. Refractometers are used to determine acid concentrations when testing automotive batteries. Finally, I question: will anyone pay attention to an automated gizmo? A bit of hands on puts a stronger focus on the subject. Be sure to be charting (p chart type) your continuous monitoring results.

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#21324

Saponifier Concentration Measurement | 26 August, 2002

Is refraction commonly used as a measurement method? => Yes, it is quite common.

Does it [refraction] provide adequate resolution? => Depends on: * What you mean by �adequate�. * When during the process [cleaning solution life] you make the measurement.

Is the [refraction] measurement affected significantly by any factor common within the process? => Yes, refraction measures total solids. So as your cleaning solution becomes �dirtier� [more loaded-up with debris washed from the board], relying on a refraction measurement can trick you into thinking that you saponifier concentration is higher than the true level. This becomes a BIG time problem for users of water-soluble temporary solder masks.

Can anyone recommend instrumentation for continuous monitoring of concentration levels using refraction? => Sure. Leica automatic refractometer [Mikie�s comments not withstanding].

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