Neutral Axis

An axis of no stress.

Nominal Size

Size of pipe or shaft used to define the internal working diameter.

Nominalize

To classify a value into an established range or category.

Non-Man Entry

Size of pipe, duct or bore less than that for man-entry.

Non-Uniform Corrosion

CorrosionThe destruction of a material or its properties because of a reaction with its (environment) surroundings. that attacks small, localized areas of the pipe. Usually results less metal loss than uniform corrosion but causes more rapid failure of the pipe due to pits and holes.