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Tapping the Low Hydrogen Porosity Problem

Tapping the Low Hydrogen Porosity Problem
By Dan Mahony, Technical Salesman, and Paul Gramp, Distributor Trainer, The Lincoln Electric Company.

Stick Welding Porosity in a weld is considered poor quality. Porosity may, or may not, be visible to the naked eye. Occasionally porosity can be found in the face of the weld while sometimes the face may appear porosity free, but deep inside the weld, porosity may exist. Porosity looks "sponge like" or like tiny bubbles in the weld. Porosity in a weld can be located using several different methods of non-destructive testing, such as radiographic (x-ray), UT (ultrasonic) and die penetrate.

"...strike the arc, then lift the electrode up for a moment or two, allowing a few drops of electrode to fall from the tip."

Although some porosity found at the beginning of a weld made with low hydrogen electrodes is not alw