1. n. [Perforating]

The radial distribution of successive perforating charges around the gun axis. Perforating gun assemblies are commonly available in 0°, 180°, 120°, 90°, and 60° phasing. The 0° phasing is generally used only in small outside-diameter guns, while 60°, 90°, and 120° phase guns are generally larger but provide more efficient flow characteristics near the wellbore.

See: perforating gun