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: a kind of downhole tool composed by axle joint,saver sub and centering device with ledges on both ends,used to steady the bit during drilling and easy to replace the centralizer after the wing panels of centralizer being abraded

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: a kind of tool with the effect of equalizing and seting upright ,consist of axle, saver sub and bush

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.

a threaded coupling under the kelly to which the joints of drill sting are make up. Save wear on the kelly threads.

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.

n: A device that turns the drillstring. It consists of one or more motors (electric or hydraulic) connected with appropriate gearing to a short section of pipe called a quill, that in turn may be screwed into a saver sub or the drillstring itself. The topdri