دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: 1. in drilling, the effective hole size. 2. in casing, the guaranteed minimum diameter of the casing. The drift diameter is important because it indicates whether the casing is large enough for a specified size of bit to pass through.

the published drift diameter for a pipe that describes the diameter of a tool that can pass through the pipe when the pipe is vertical (no doglegs).