دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n pi: see kelly bushing rollers. drive shaft n: in a top drive, d1e shaft that comes out of the drives drilling motor. Usually, crew members attach a saver sub (a short pipe fitting) to the drive shaft and attach the top joint of drill pipe to the sub. The drive shaft transmits the motors rotating fon:e to the drill string and bit. See top drive.

n: refer tokelly bushing rollers

n pi: rollers in the kelly bushing that roll against the flat sides of the kelly and allow it to move freely upward or downward. Also called drive rollers.

n: the inner surface of kelly bushing is gyro wheel and contacts the level of kelly.