دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: a heavy and relatively short length of pipe that fits in the drill stem between the kelly and the drill pipe. The threads of the drill pipe mate with those of the sub, minimising wear on the kelly.

n: connected with the kelly ,it often suitable make up and breakout.


a short threaded sub that is made up to the kelly and to which the drill string is connected. The connections are made to the sub, saving wear on the kelly threads.

n: see kelly saver sub.

n: an expendable substitute device made up in the drill stem to absorb much of the wear between the frequently broken joints (such as between the kelly or top drive and the drill pipe). See kelly saver sub.

n: The sub between the drill string ,which be used to decrease the wear when make up and breakout.

n: a short, threaded piece of pipe used to adapt parts of the drilling string that cannot otherwise be screwed together because of differences in thread size or design. A sub (i.e., a substitute) may also perform a special function. Lifting subs are used with drill collars to provide a shoulder to fit the drill pipe elevators;a kelly saver sub is placed between the drill pipe and the kelly to prevent excessive thread wear of the kelly and drill pipe threads;a bent sub is used when drilling a directional hole.

n: A shot section of pipe ,tubing ,or drill pipe run into a hole.

a short section of pipe, used to describe tools or to solve space-out gaps.