AU2021101670A4

AU2021101670A4 - Method and device for reentry into turbo type multilateral well

Info

Publication number: AU2021101670A4
Application number: AU2021101670A
Authority: AU
Inventors: Yimin Chen; Chunyan FENG; Deming LI; Qin Li; Siyang Qiu; Xiangyi Yi; Jianwei Zhang; Tingting Zhang
Original assignee: Chengdu Univeristy of Technology
Current assignee: Chengdu Univeristy of Technology
Priority date: 2020-12-18
Filing date: 2021-03-31
Publication date: 2021-05-20
Anticipated expiration: 2029-03-31
Also published as: CN112627729A; CN112627729B

Abstract

The disclosure relates to a method and device for reentry into a turbo type multilateral well, including an upper drill rod or oil pipe, a turbine section, a hydraulic anchor and a guider, wherein a guide hole is formed in the guider, a flexible rod penetrates through the guide hole, one end of the flexible rod is connected with a piston body, the other end of the flexible rod is connected with a seeker, the seeker can penetrate out of the guider along the guide hole, a spring is sleeved at one end of the flexible rod connected with the piston body, the piston body slides in a channel consisting of the drill rod or oil pipe, the turbine section inner pipe and the inner cavity of the hydraulic anchor, a one-way cavity is axially formed on the top surface of the piston body, upper and lower two pairs of through holes are distributed inside the one-way cavity in a radial direction, and an included angle between the two pairs of through holes is 90. The method for reentry into a multilateral well provided by the disclosure is simple to operate, and rapid and efficient to recognize. By utilizing this method, works of reliving anchoring and guiding into other wellbores again can be completed in a next tubular column in the radial multilateral wellbore, and therefore the achievement method is simple and reliable. 1/2 4G 1-9 FIG.1I

Description

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4G

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FIG.1I

METHOD AND DEVICE FOR REENTRY INTO TURBO TYPE MULTILATERAL WELL TECHNICAL FIELD

[0001] The disclosure belongs to the field of drilling and production equipment in oil and natural gas engineering, and relates to a downhole operation method, particularly to a method and device for reentry into a multilateral well

BACKGROUND OF THE PRESENT INVENTION

[0002] A multilateral well is an effective means to improve the efficiency of oilfield development. It is a well where two or more multilateral wellbores from the middle side of a main wellbore, which has reduced well quantity, reduced development cost and improved single-well yield and oil gas reservoir recovery rate. Since there are multiple multilateral wellbores under the multilateral well, it is needed for various downhole tools to be guided to reenter the multilateral wellbore by virtue of positioning when entering the bottom of the well after well completion. If there are multiple branches in the multilateral well or it is needed to allow multiple sets of tools to enter, it is necessary to consume a lot of energy and time to complete the loading and taking of guiding tools, which causes huge consumption of downhole operation cost of the oil and gas well.

[0003] By patent retrieval, the following related publication invention patents are found:

[0004] 1. A method for reentry into a tubular column of a multilateral well in the later stage of operation (CN101787856A), in which a principle of cooperating a guiding key with a guiding groove is utilized to prearrange the guiding groove above the multilateral wellbore, and an included angle between projections of the guiding groove and the multilateral wellbore on a horizontal plane is a guiding angle. When putting into the tubular column, a bending shoe with the guiding key and a certain angle is prearranged, an included angle between the guiding key and the bending shoe on the horizontal plane should be equal to the guiding angle. By using cooperation of the guiding key and the guiding groove when putting into the tubular column, the entry of the bending shoe into the multilateral wellbore is completed, thereby guiding the tubular column to enter the multilateral wellbore in the later stage of operation.

[0005] This method completes the reentry operation of the multilateral wellbore, but it is needed to prearrange a guide sleeve in the main shaft at the early stage of operation, and the guiding angle needs to be known. In such a way, at the early stage of operation, it is needed to deliver the guide sleeve into the prearranged location utilizing the tubular column for anchoring and correctly measuring the guiding angle. The operation procedure is tedious and complicated, and time-consuming.

[0006] 2. A method for selective reentry into a multilateral well (CN104405318A), which is completed by cooperating three tools, namely, a downhole permanent positioning tool, a main wellbore reentry guiding tool and a multilateral reentry guiding tool. First, the downhole permanent positioning tool is put into the main wellbore according to a certain angle followed by a main wellbore reentry guiding tool, an annular guide bevel faces the multilateral wellbore and then the multilateral wellbore reentry guiding tool is put to extend from a lateral mouth into the multilateral wellbore through the guiding of the annular guide bevel, thereby guiding the tubular column to enter the multilateral wellbore in the later stage of operation.

[0007] This method can selectively guide an operation pipe string into the main wellbore or multilateral wells, but it is similarly needed to put the positioning tool in the early stage of operation and positioning is needed, so as to cause the operation construction to be tedious and complicated. In addition, after the reentry operation of the multilateral wellbore is ended, the permanent positioning tool is still in the main wellbore, which brings many inconveniences for other construction operations of the future main wellbore.

[0008] 3. A method and device for selective reentry into a multilateral well (CN1932231A). According to this method, the selective reentry device is bent to a certain extent along a certain direction in a manner of pressure drop, then slowly put and rotates the reentry tubular column; when the bending lateral force makes the bending orientation of the device of the disclosure consistent with the multilateral wellbore, the device of the disclosure guides the operation tubular column to enter the multilateral wellbore.

[0009] The method is easy to implement and does not need to prearrange the guide device, so as to simplify the construction process, and to guide the operation pipe string to enter the multilateral well to complete the subsequent construction. But there are the following disadvantages: (1) the time when the reentry device enters the multilateral wellbore cannot be judged, and the upper tubular column easily causes the lower tubular column to twist under the state of rotation; (2) after the reentry device guides the reentry tubular column into the multilateral well, the reentry device is still in the multilateral well and is in the front end of the wellbore, which will bring inconveniences for other construction operations in the multilateral wellbore. If it is required for repetitive task, the reentry device needs to be put many times.

SUMMARY OF PRESENT INVENTION

[0010] It is an objective of the disclosure to overcome the defects in the prior art and provide a method and device for reentry into a radial multilateral well. The method is simple to operate, and rapid and efficient to recognize. By using this method, works of reliving anchoring and guiding into other wellbores again are completed on the next tubular column in the radial multilateral wellbore, and achievement method is simple and reliable.

[0011] The technical solution to solve the technical problem by the disclosure is as follows:

[0012] Provided is a device for reentry into a turbo type multilateral well, comprising an upper drill rod or oil pipe, a turbine section, a hydraulic anchor and a guider, wherein a guide hole is formed in the guider, a flexible rod penetrates through the guide hole, one end of the flexible rod is connected with a piston body, the other end of the flexible rod is connected with a seeker, the seeker can penetrate out of the guider along the guide hole, a spring is sleeved at one end of the flexible rod connected with the piston body, the piston body slides in a channel consisting of the drill rod or oil pipe, the turbine section inner pipe and the inner cavity of the hydraulic anchor, a one-way cavity is axially formed on the top surface of the piston body, upper and lower two pairs of through holes are distributed inside the one-way

cavity in a radial direction, an included angle between the two pairs of through holes is 90.

[0013] Furthermore, the turbine section comprises a stator assembly and a rotator assembly, the stator assembly comprises a turbine outer pipe and a stator, the stator is fixed on the inner wall of the turbine outer pipe, the rotator assembly comprises a turbine inner pipe and a rotator, the rotator is fixed on the outer wall of the turbine inner pipe, the rotator is engaged with the stator, a fluid inlet bath and a fluid inlet hole are formed in the lower part of the turbine inner pipe, fluid can flow into the turbine section via the fluid inlet bath and the fluid inlet hole, a fluid outlet hole is formed in the upper part of the turbine outer pipe, and the fluid can flow out of the turbine section via the fluid outlet hole.

[0014] Furthermore, the stator assembly also comprises an outer pipe end cover, one end of the turbine outer pipe is in threaded connection with the outer pipe end cover, and the other end is in threaded connection with the drill rod or oil pipe.

[0015] Furthermore, the rotator assembly also comprises an inner pipe end cover, one end of the inner pipe end cover is in threaded connection with the turbine inner pipe, and the other end of the inner pipe end cover is in thread engagement with the hydraulic anchor.

[0016] Furthermore, the stator assembly and the rotator assembly are connected through up and down limiting bearings.

[0017] Furthermore, the use method of the device is as follows:

[0018] (1) when an entry device is put into a target location, fluid is pumped into a tubular column to push a piston to downward move;

[0019] (2) when a seeker is abutted against a casing pipe, the fluid continues to be pumped, so that a pressure in the pipe continuously rises, and the fluid continues to push the piston to downward move and compress a spring;

[0020] (3) when the piston moves downward to an upper through hole to be communicated with the fluid inlet groove of the turbine inner pipe, the fluid in the cavity of the piston flows through the fluid inlet hole from the fluid inlet groove into the turbine section, the pressure in the upper pipe is dropped, the piston stops downward moving, the fluid continues to be continuously pumped into the tubular column to keep the balance between fluid pressure in the pipe and a spring counterforce which the piston bears so that the location of the piston is unchanged;

[0021] (4) when the fluid is continuously pumped into the tubular column, the fluid flows into a gap between the stator and the rotator of the turbine section through the tubular column, the piston cavity, the upper through hole, the turbine inner pipe fluid inlet groove, the fluid inlet hole of the turbine inner pipe, the fluid pushes the rotator to rotate and flows out from the fluid outlet hole of the turbine outer pipe, and flows to the ground via a shaft and an annular space of the tubular column;

[0022] (5) when the fluid pushes the rotator to rotate, the turbine inner pipe drives the piston and the guider, the seeker and the like in the lower tubular column to together rotate, at this moment, the upper tubular column and the turbine outer pipe do not rotate, only the lower tubular column of the turbine section rotates under the action of the fluid, and meanwhile the tubular column lifts;

[0023] (6) when the seeker enters the multilateral wellbore, the pressure in the pipe is larger than the counterforce of the piston, the piston continues to downward move to cause the malposition of the upper through hole and the fluid inlet groove, the fluid in the tubular column stops entering the turbine section, the turbine section stops working, and the rotator and the turbine inner pipe stop rotating;

[0024] (7) the pressure in the pipe continues to push the piston to downward move, until the lower through hole is communicated with the hydraulic anchor channel, and the hydraulic pressure anchors the hydraulic anchor; and

[0025] (8) the pressure is pumped again to push the piston to downward move, so as to continue to open a bypass port to relive the pressure.

[0026] Furthermore, the counterforce direction bore by the stator is a fastening direction where the turbine outer pipe and the upper tubular column are in threaded connection.

[0027] The disclosure has the advantages and beneficial effects:

[0028] 1. Compared with CN101787856A, the disclosure does not need to position and prefabricate the device before the device of the disclosure is put. In the disclosure, the tubular column is utilized to directly put the device of the disclosure, and the guider positioning is directly completed during the guiding. After the guider is anchored, the seeker is taken out to complete the guiding operation. The whole process can only be completed by putting and taking out the tubular column, which saves operation procedures and saves time.

[0029] 2. Compared with CN104405318A, the disclosure does not need to put the permanent positioning tool. After the guiding operation is finished, the anchor of the guider can be released and the reentry guiding operation of the next multilateral wellbore can be continued. No downhole equipment material is consumed, cost is saved, and operation is simple.

[0030] 3. Compared with CN1932231A, the disclosure does not need to place the seeker at the front end of the reentry tubular column, and the reentry guiding method is more reasonable, safe and reliable. The disclosure is used to identify and judge the state of the seeker by means of the turbine section, which not only protects the reentry safety of the tubular column, but also identifies whether the seeker enters the multilateral well. In the method of the disclosure, the guide and the seeker are put together into the main shaft together, and the seeker is aligned with the multilateral wellbore and the position of the guider is accurately anchored. After the seeker is removed, the reentry of the tubular column can be carried out according to the construction requirements, without the limitation of the pre-positioned guider.

[0031] 4. Compared with the existing technologies represented by CN101787856A, CN104405318A and CN1932231A, in the disclosure, the reentry guiding operation is performed in the radial multilateral well and the ultra short radius multilateral well. Because the radial multilateral well and the ultra short multilateral well have small multilateral wellbores, the above technology adopts bending shoes or prefabricated bending seeker, which can not enter smoothly, and large-scale or complex tools cannot successfully complete the demanded operation in a well with a small diameter. The method provided by the disclosure can use a coiled tube (which is a common tool for radial horizontal well drilling and completion, with a diameter of about 1 inch-2 inches) to complete the reentry guiding operation in the radial multilateral well and the ultra short radius multilateral well. The method is simple and reliable.

DESCRIPTION OF THE DRAWINGS

[0032] Fig. 1 is a structural diagram of a device;

[0033] Fig. 2 is a structure diagram of a turbine section;

[0034] Fig. 3a is a structure diagram of a turbine outer pipe;

[0035] Fig. 3b is a sectional view taken along A-A in Fig.3a;

[0036] Fig.4a is a structure diagram of a turbine inner pipe;

[0037] Fig.4b is a sectional view taken along B-B in Fig.4a;

[0038] Fig.5 is a schematic diagram of a working state of a method device (initial);

[0039] Fig.6 is a schematic diagram of a working state of a method device (pressurization, piston propulsion, and a seeker is abutted against a well wall);

[0040] Fig. 7 is a schematic diagram of a working state of a method device (continue downward moving, spring compression, starting the turbine);

[0041] Fig. 8 is a schematic diagram of a working state of a method device ( rotating and upwardly lifting the tubular column);

[0042] Fig. 9 is a schematic diagram of a working state of a method device (successful addressing, downward moving the piston, close the turbine);

[0043] Fig. 10 is a schematic diagram of a working state of a method device (continue downward moving, start the hydraulic anchor device for anchoring);

[0044] Fig.1 1is a schematic diagram of a working state of a method device (continue downward moving, start bypass system for release the pressure).

[0045] Fig.12 is a schematic diagram of a working state of a method device (fishing with the coiled tube ).

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0046] Next, the disclosure will be further described through specific examples, the following examples are only illustrative but not limiting, and cannot whereby limit the protective scope of the disclosure.

[0047] A device for reentry into a multilateral well comprises an upper drill rod or oil pipe 1, a turbine section 27, a hydraulic anchor 13, a guider 14 and a lower centralizer 17 which are connected in turn from top to bottom. An upper centralizer 22 is sleeved outside the turbine section, an arc-shaped guide hole 16 is formed in the guider, a flexible rod 18 penetrates through the guide hole 18, and one end of the flexible rod 18 is connected with the piston body 21, the other end of the flexible rod is connected with a seeker 15, and the seeker penetrates out of the guider along the guide hole. One end of the flexible rod connected with the piston body is sleeved with a spring 20, the piston body slides in a channel consisting of the drill rod or oil pipe, the turbine section inner pipe, the inner cavity of the upper centralizer and the inner cavity of the hydraulic anchor. A one-way cavity 24 is axially formed on the top surface of the piston body, upper and lower two pairs of through holes are distributed inside the one-way cavity in a radial direction, the upper through hole 25 is used for starting the turbine, the lower through hole is used for anchoring and pressure relief of the hydraulic anchor, so as to avoid the lower through hole to be communicated with the turbine first during the downward movement, and an included angle between the two pairs of through holes is

900.

[0048] The turbine section includes a stator assembly and a rotator assembly, the stator assembly includes a turbine outer pipe 2, a stator 4, an outer pipe end cover 11, a seal ring 10 and a stator limiting ring 7, wherein one end of the turbine outer pipe is in threaded connection with the drill rod or oil pipe, the other end is in threaded connection with the outer pipe end cover, the stator is fixed on the inner wall of the outer pipe, and the seal ring plays a role in sealing and limiting. The rotator assembly includes a turbine inner pipe 6, a rotator 5 and a rotator limiting ring 8, wherein the rotator is fixed on the outer wall of the inner pipe, the rotator is engaged with the stator, wherein one end of the turbine inner pipe is in threaded connection with the inner pipe end cover 12, and the inner pipe end cover is in thread engagement with the hydraulic anchor. The stator assembly and the rotator assembly are connected through upper and lower limiting bearings 3 and 9, the upper and lower limiting bearings are used for transmitting an axial force and achieving circumferential relative force. An fluid outlet hole 26 is formed on the upper part of the turbine outer pipe, and the fluid can flow out of the turbine section via the fluid outlet hole. A fluid inlet groove and a fluid inlet hole 23 are formed on the lower part of the turbine inner pipe, and fluid can flow into the turbine section via the fluid inlet groove and a fluid inlet hole.

[0049] A method for reentry into a multilateral well, taken by a radial horizontal well as an example, includes the following steps:

[0050] (1) when an entry device is put into a target location, fluid is pumped into a tubular column to push a piston to downward move;

[0051] (2) when a seeker is abutted against a casing pipe, the fluid continues to be pumped, so that a pressure in the pipe continuously rises, the fluid continues to push the piston to downward move and compress a spring;

[0052] (3) when the piston moves downward to an upper through hole to be communicated with the fluid inlet groove of the turbine inner pipe (the fluid inlet groove and the lower through hole direction are included at an angle of 90 and do not form communication), the fluid in the cavity of the piston flows through the fluid inlet hole from the fluid inlet groove into the turbine section (between the turbine inner pipe and the turbine outer pipe), the pressure in the upper pipe is dropped, and the piston stops downward moving. The fluid continues to be continuously pumped into the tubular column to keep the balance between fluid pressure in the pipe and a spring counterforce which the piston bears so that the location of the piston is unchanged;

[0053] (4) when the fluid is continuously pumped into the tubular column, the fluid flows into a gap between the stator and the rotator of the turbine section through the tubular column, the piston cavity, the upper through hole, the turbine inner pipe fluid inlet groove, the fluid inlet hole of the turbine inner pipe, the fluid pushes the rotator to rotate and flows out from the fluid outlet hole of the turbine outer pipe, and flows to the ground via a shaft and an annular space of the tubular column;

[0054] (5) when the fluid pushes the rotator to rotate, the turbine inner pipe drives the piston and the guider, the seeker and the like in the lower tubular column to together rotate ( at this moment, the upper tubular column and the turbine outer pipe do not rotate, only the lower tubular column of the turbine section rotates under the action of the fluid, and meanwhile the tubular column lifts. Considering the counterforce generated by the fluid on the stator, the direction of the fluid counterforce stressed by the stator is a fastening direction of threaded connection of the turbine outer pipe and the upper tubular column in order to avoid the releasing of the turbine outer pipe and the upper tubular column);

[0055] (6) when the seeker enters the multilateral wellbore, the pressure in the pipe is larger than the counterforce of the piston, the piston continues to downward move to cause the malposition of the upper through hole and the fluid inlet groove, the fluid in the tubular column stops entering the turbine section, the turbine section stops working (the rotator and the turbine inner pipe stop rotating);

[0056] (7) the pressure in the pipe continues to push the piston to downward move, until the lower through hole is communicated with the hydraulic anchor channel 19, the hydraulic pressure anchors the hydraulic anchor; and

[0057] (8) the pressure is pumped again to push the piston to downward move, so as to continue to open a bypass port to relive the pressure

[0058] The reentry device and method are applied to not only the radial horizontal well, but also all multilateral well types. Because the reentry of the radial horizontal well is the most difficult, description is made by using the reentry process of the radial horizontal well as an example.

[0059] The above description is only the preferred embodiment of the disclosure. It should be noted that, several deformations and improvements can be made by persons of ordinary skill in the art without departing from the concept of the disclosure, which all belong to the protective scope of the disclosure.

Claims

We claim: 1. A device for reentry into a turbo type multilateral well, comprising an upper drill rod or oil pipe, a turbine section, a hydraulic anchor and a guider, wherein a guide hole is formed in the guider, a flexible rod penetrates through the guide hole, one end of the flexible rod is connected with a piston body, the other end of the flexible rod is connected with a seeker, the seeker can penetrate out of the guider along the guide hole, a spring is sleeved at one end of the flexible rod connected with the piston body, the piston body slides in a channel consisting of the drill rod or oil pipe, the turbine section inner pipe and the inner cavity of the hydraulic anchor, a one-way cavity is axially formed on the top surface of the piston body, upper and lower two pairs of through holes are distributed inside the one-way cavity in a radial

direction, and an included angle between the two pairs of through holes is 90.
2. The device according to claim 1, wherein the turbine section comprises a stator assembly and a rotator assembly, the stator assembly comprises a turbine outer pipe and a stator, the stator is fixed on the inner wall of the turbine outer pipe, the rotator assembly comprises a turbine inner pipe and a rotator, the rotator is fixed on the outer wall of the turbine inner pipe, the rotator is engaged with the stator, a fluid inlet bath and a fluid inlet hole are formed in the lower part of the turbine inner pipe, fluid can flow into the turbine section via the fluid inlet bath and the fluid inlet hole, a fluid outlet hole is formed in the upper part of the turbine outer pipe, and the fluid can flow out of the turbine section via the fluid outlet hole.
3. The device according to claim 2, wherein the stator assembly also comprises an outer pipe end cover, one end of the turbine outer pipe is in threaded connection with the outer pipe end cover, and the other end is in threaded connection with the drill rod or oil pipe.
4. The device according to claim 2, wherein the rotator assembly also comprises an inner pipe end cover, one end of the inner pipe end cover is in threaded connection with the turbine inner pipe, and the other end of the inner pipe end cover is in thread engagement with the hydraulic anchor.
5. The device according to claim 2, wherein the stator assembly and the rotator assembly are connected through up and down limiting bearings.
6. The device according to claim 1, wherein the use method is as follows: (1) when an entry device is put into a target location, fluid is pumped into a tubular column to push a piston to downward move; (2) when a seeker is abutted against a casing pipe, the fluid continues to be pumped, so that a pressure in the pipe continuously rises, the fluid continues to push the piston to downward move and compress a spring; (3) when the piston moves downward to an upper through hole to be communicated with the fluid inlet groove of the turbine inner pipe, the fluid in the cavity of the piston flows through the fluid inlet hole from the fluid inlet groove into the turbine section, the pressure in the upper pipe is dropped, the piston stops downward moving, and the fluid continues to be continuously pumped into the tubular column to keep the balance between fluid pressure in the pipe and a spring counterforce which the piston bears so that the location of the piston is unchanged; (4) when the fluid is continuously pumped into the tubular column, the fluid flows into a gap between the stator and the rotator of the turbine section through the tubular column, the piston cavity, the upper through hole, the turbine inner pipe fluid inlet groove, the fluid inlet hole of the turbine inner pipe, and the fluid pushes the rotator to rotate and flow out from the fluid outlet hole of the turbine outer pipe, and flows to the ground via a shaft and an annular space of the tubular column; (5) when the fluid pushes the rotator to rotate, the turbine inner pipe drives the piston and the guider, the seeker and the like in the lower tubular column to together rotate, at this moment, the upper tubular column and the turbine outer pipe do not rotate, only the lower tubular column of the turbine section rotates under the action of the fluid, and meanwhile the tubular column lifts; (6) when the seeker enters the multilateral wellbore, the pressure in the pipe is larger than the counterforce of the piston, the piston continues to downward move to cause the malposition of the upper through hole and the fluid inlet groove, the fluid in the tubular column stops entering the turbine section, the turbine section stops working, the rotator and the turbine inner pipe stop rotating; (7) the pressure in the pipe continues to push the piston to downward move, until the lower through hole is communicated with the hydraulic anchor channel, and the hydraulic pressure anchors the hydraulic anchor; and

(8) the pressure is pumped again to push the piston to downward move, so as to continue to open a bypass port to relive the pressure.