RU2418147C1 - Calibrating device of extension-type well shaft - Google Patents

Abstract

FIELD: oil and gas industry.

SUBSTANCE: calibrating device of extension-type well shaft includes housing with inclined slots and spring-loaded stock arranged in it, piston rigidly connected from below to the stock, which is annular and arranged in the chamber formed with outer stock wall and inner wall of the housing, legs with teeth on working surface, which are fixed in inclined slots of the housing and connected by means of rods to piston. Lower reducer with inner converging channel is connected from below to housing and equipped below annular narrowing with annular extension and restrictor. Bushing with seat for tripping ball is inserted inside annular constriction and fixed with shear member, and tightly cuts out the interaction of inner cavity of the stock with chamber and has the possibility of interaction with restrictor when it is moved downwards. At that, height of bushing is less than height of annular extension of lower reducer to restrictor. Working surface of legs is made in the form of protruding screw blades on which calibrating teeth are arranged in rows and overlap each other, and installed flush with screw surface of the appropriate blades.

EFFECT: improving reliability and service life time of construction, which provides calibrated well shaft strictly of required diametre throughout the length of expanded interval, creates no additional load on drill pipes; and enlarging life time of equipment of expanding tool.

2 cl, 1 dwg

Description

The invention relates to drilling equipment in the oil and gas industry, in particular to devices for increasing the diameter of a well in a predetermined interval.

A device-type calibrator is known as a blade type (Abubakirov V.F. et al. Drilling equipment: Handbook, 2 volumes. Drilling tools. - M.: Nedra Publishing House, 2003. - P.196). The blade calibrator consists of a one-piece milling body, interchangeable blades on it, reinforced with carbide elements, sub with coupling and nipple lock threads. Carbide elements are installed in the holes of the blades and pressed.

The disadvantage of this design is the impossibility of providing a calibrated wellbore of the required diameter and quality when expanding the wellbore with a sliding expander, since it is a rigid non-expanding structure and, as a result, the possibility of under-disclosure of the profiler pipe installed in an expandable interval leading to an emergency and re-drilling the wellbore.

The closest in technical essence and the achieved result is “Expander wells” (RF patent No. 57792, E21B 7/28, publ. Bull. No. 30 dated 10/27/2006), containing a housing with inclined grooves and a rod placed in it, interacting with the piston rod, which is made annular and placed in the chamber formed by the outer wall of the rod and the inner wall of the housing, fixed in inclined grooves of the housing and connected by means of rods to the piston of the paws with teeth on the working surface, the working surface of the paws is formed expanding from the center and devices with variable increasing curvature upward, relative to the location in the well, and a curved outer surface cut along the middle of the sample, the teeth on the working surface are arranged in longitudinal rows, and the first and first rows of teeth are fixed obliquely relative to their axes rotation, while the upper teeth are made in the form of inclined gage plates located along the working surface, and the teeth in rows are made with the possibility of interaction Ia with the borehole wall during rotation, without repeating the previous trajectory.

The disadvantages of this extender as a calibrator are:

- the calibrated shaft does not provide the required diameter and quality, since the length of the calibrating section is insufficient, and its shape is not optimal and, as a result, the possibility of under-disclosure of the overlap profile pipe is not ruled out, leading to an emergency situation and the borehole is being drilled;

- due to the lack of a valve during insertion of the expander, it is jammed, as additional torque is created, which can lead to breakage of drill pipes;

- low resource of arms (teeth) of the expander due to vibrations and resonance phenomena that occur during operation of the expander as a calibrator.

The technical task of the proposed device is to create a reliable and durable design that provides a calibrated wellbore of strictly required diameter along the entire length of the expandable interval, which does not create additional load on drill pipes and increases the expander’s weapon life many times.

The technical problem is solved by the calibrator of the wellbore, comprising a housing with inclined grooves and a spring-loaded rod located therein, a piston rigidly connected from below to the rod, which is annular and placed in a chamber formed by the outer wall of the rod and the internal wall of the housing, fixed in inclined slots in the housing and connected by means of rods with a piston to the paws with teeth on the working surface, and a lower sub with an internal tapering channel, connected from below to the body.

New is that the lower sub below the annular restriction is equipped with an annular extension and a stop, and a sleeve with a saddle fixed by a shear element is inserted inside the annular narrowing under the ball being dropped, hermetically blocking the message of the inner cavity of the stem with the camera and made to interact with the limiter when moving down, moreover, the height of the sleeve is less than the height of the annular expansion of the lower sub to the limiter.

Also new is the fact that the working surface of the paws is made in the form of protruding screw blades, on which calibrating teeth are placed in rows with overlapping each other, mounted flush with the screw surface of the respective blades.

The drawing shows the design of the calibrator of the wellbore with a partial axial section.

The sliding well calibrator comprises a housing 1 with inclined grooves 2 and a spring-loaded rod 3 located in the housing 1, rigidly connected from below to a piston 4, which is annular and placed in the chamber 5, formed by the outer wall 6 of the rod 3 and the inner wall 7 of the housing 1. B the inclined grooves 2 of the housing 1 are fixed and connected by rods 8 to the piston 4 paws 9 with teeth 10 on the working surface 11. The lower sub 12 with the inner tapering channel 13 is connected from below to the housing 1. The lower sub 12 below the annular narrowing 13 is equipped an annular extension 14 and a limiter 15. A sleeve 17 fixed with a shear element 16 is inserted inside the annular narrowing 13 under the drop ball 19, hermetically blocking the communication of the internal cavity 20 of the rod 3 with the chamber 5. The sleeve 17 is configured to interact with the limiter 15 when moving down moreover, the height of the sleeve 17 is made less than the height of the annular extension 14 of the lower sub 12 to the limiter 15. The working surface 11 of the legs is made in the form of protruding screw blades 21, on which are placed s overlapping each other calibrating teeth 10 mounted flush with the working surface of the screw 11 corresponding to 21 blades.

The calibrator of the sliding wellbore operates as follows.

The calibrator using the upper thread 22 is connected to the drill pipe string, and using the lower thread 23 of the sub 12 is connected to a sliding expander (not shown). After that, the complete assembly is lowered into the well (not shown in the drawing) in the expansion interval (not shown in the drawing). Then the layout is given a rotational and translational movement downward, pumping fluid along its internal cavity. At the same time, the calibrator of the wellbore is in the transport position, and the sliding expander, located below, occupies the working position and the expander cuts into the walls of the wellbore. After the insertion process is completed and the interval is extended by the length of the calibrator, a ball 19 is thrown into the inner cavity of the pipe string, which sits in the seat 18. At the same time, a pressure drop is created above the ball 19, and the sleeve 17 with the ball 19, destroying the shear element 16, moves from the annular narrowing 13 down into the annular extension 14 to the stop 15, communicating the internal cavity of the drill pipe with the chamber 5. Due to the fact that the height of the sleeve 17 is less than the height of the annular extension 14 of the fluid flow down does not overlap. Further, under the influence of the differential pressure in the chamber 5, the piston 4 by means of rods 8 extends the legs 9 along the inclined grooves 2 of the housing 1 upwards to the working position. Due to the fact that the working surface 11 of the paw 9 is made in the form of screw blades 21, a calibrated barrel of the required diameter and quality is provided, and the armament of the expander located below the calibrator is maintained. And thanks to the presence of teeth 10 placed in rows with overlapping each other, long-term wear resistance of the paws is ensured without loss of diameter. Due to the presence of the valve during insertion of the expander, it does not jam due to additional torque, which eliminates the breakage of drill pipes. All of the above can significantly increase the quality of the expandable surface and increase the life of the expander wells.

Upon completion of the work, the longitudinal flow, rotation of the downhole equipment and the flow of fluid through it are stopped. As a result, under the action of its spring 24, the rod 3 with the piston 4, rods 8 and paws 9 are moved down. As a result, the calibrator returns to its original (transport) position and is removed from the well.

The proposed design of the calibrator provides a calibrated wellbore of strictly necessary diameter along the entire length of the expandable interval, does not create additional load on the drill pipe and greatly increases the armament resource of the expander.

Claims (2)

1. A calibrator for a sliding wellbore, comprising a housing with inclined grooves and a spring-loaded rod located therein, a piston rigidly connected from below to the rod, which is annular and placed in a chamber formed by the outer wall of the rod and the internal wall of the housing, fixed in inclined grooves of the housing and connected by means of rods with a piston of a paw with teeth on the working surface, and a lower sub with an inner tapering channel connected from below to the body, characterized in that the lower sub is lower than the annular narrow The cylinder is equipped with an annular extension and a limiter, and a sleeve fixed with a shear element is inserted inside the annular narrowing under the ball being dropped, hermetically blocking the message of the inner cavity of the rod with the chamber and made to interact with the limiter when moving downward, and the height of the sleeve is less than the height of the annular extension of the lower sub to the limiter. 2. The calibrator of the sliding wellbore according to claim 1, characterized in that the working surface of the paws is made in the form of protruding helical blades, on which calibrating teeth are placed in rows overlapping each other, mounted flush with the helical surface of the respective blades.