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Specific Gravity

Steven

#26239

Specific Gravity | 4 November, 2003

A Customer has asked me about a chart that allows for temperature compensation when measuring specific gravity in a wave solder machine. Anyone know of any temp. conv. chart? Thanks

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#26243

Specific Gravity | 4 November, 2003

No don't know about such a chart. But, consider changing the method used to check flux activity. Consult your flux supplier for a test kit that will measure actual activity (acidity). SG is a suggestive method.

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#26247

Specific Gravity | 4 November, 2003

We have this in our hydrometer use notes. We assume it's from our hydrometer supplier.

Temperature Correction

All hydrometer readings must be corrected from the temperature they were read at, to the temperature the hydrometer was designed for. Most hydrometers are set to 15.6*C (60*F). Some hydrometers calibrated are to 20*C. Check any hydrometer prior to use!

The difference each degree of temperature makes to the specific gravity is not constant, however approximate corrections are:

For every degree the sample is above the hydrometer's calibrated temperature, add 0.001

For every degree the sample is below the hydrometer's calibrated temperature, take off 0.001

This is sufficiently accurate for temperatures between 0*C and 40*C, but should not be used outside this temperature range.

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#26248

Specific Gravity | 4 November, 2003

Hi

This will vary between flux used your flux supplier should be able to furnish with these easily.

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Steven

#26271

Specific Gravity | 5 November, 2003

You folks are AMAZING. Thank you very much for all of your input. Hope it helps the customer.

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Reflow Oven