دیکشنری تخصصی مهندسی نفت - نسخه آنلاین

n: see bent sub.

n: See bent sub.

n: a short cylindrical device installed in the drill stem between the bottom most drill collar and a downhole motor. Its purpose is to deflect the downhole motor off vertical to drill a directional hole. See drill stem.

a short section of a tool or pipe that is formed at an angle or is modified downhole by a motor to assist in entering deviated wellbores or drilling off the path of the wellbore.

n: a bent sub which can slope at two directions ,connected between the bit and the dynamic drill tool

n: a drilling tool made up in the drill string directly above the bit. It causes the bit to turn while the drill string remains fixed. It is used most often as a deflection tool in directional drilling, where it is made up between the bit and a bent sub (or, sometimes, the housing of the motor itself is bent). Two principal types of down-hole motor are the positive-displacement motor and the downhole turbine motor. Also called mud motor.

n: A special tool mounted in the BHA (q.v.) to drive the bit without rotating the drill string from surface (see positive displacement motor).

n: a kind of bent sub formed by cascading the plug,catch,toggle
and so on .the regulation of the bending angle is hydraulically operated and the adjustable extent is 0-5degrees and the increment is 0.5degrees

n: a tool that under certain hydraulic pressure become curly, it is used to fish drilling tool at the out of round oversized hole.

n: a sub part of which is formed in the shape of a horseshoe and used to orient the drill stem downhole.

n: the guide shoe on the lower end of a survey tool: it locates into the key-way of the orienting sub.the survey tool can then be properly aligned with the bent sub.

a bias cut across the pipe or tool body on the end to aid in entering restricted openings.

n: a special sub that contains a key or slot,which must be aligned with the scribe line of the bent sub.a surveying instrument can then be run into the sub, aligning itself with the key to give the orientation of the scribe line, which defines nthe toolface.

n: a reference line cut on the inside bend of a bent sub to indicate the toolface.

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.