Pipe and tubing that suffer from general corrosion are

• A. Thinned from one side, or the other, or both
• B. Thinned from one side only
• C. Thinned from the other side only
• D. Thinned evenly around the circumference

Answer: (A)

General corrosion is an attack that occurs more or less uniformly over the exposed surface. In pipe and tubing this means the wall gets thinner at about the same rate all the way around the circumference, not preferentially on one side. Over time you’d expect to see uniform thinning around the pipe as the corrosion proceeds.

If thinning is seen on just one side or localized to a small area, that points to localized forms of corrosion or other mechanisms like flow-accelerated wear, deposits causing differential aeration, or crevice corrosion, rather than general (uniform) corrosion.

So the description that best represents general corrosion is thinning evenly around the circumference.