How can damp SAW flux be re-dried?

• A. Heating for about 1 hour at approximately 750 F
• B. Soak in water then air dry
• C. Cool to below room temperature
• D. Freeze overnight

Answer: (A)

Damp SAW flux contains absorbed moisture that can interfere with slag formation and weld quality, so the goal is to drive that water off without altering the flux chemistry. Heating the flux to about 750 F for roughly an hour provides enough heat to evaporate the entrained water inside the granules and any bound moisture, restoring it to a dry, free-flowing state. This temperature is high enough to remove moisture but not so high as to damage or fuse the flux.

Soaking in water would add moisture instead of removing it, and simply air drying or cooling to below room temperature won’t effectively drive out the moisture. Freezing overnight isn’t helpful either and can lead to condensation or other moisture-related issues when the flux returns to room temperature.