CN111236834A - A self-balancing torque drilling method and device for coiled tubing - Google Patents

Abstract

The invention provides a self-balancing torque drilling method and device for coiled tubing, and relates to the field of oil and gas drilling and completion. The end of the coiled tubing is serially connected with a connector, a drill pipe, a first drilling unit and a second drilling unit. The rotation direction of the first drilling unit is opposite to that of the second drilling unit. The self-balancing torque drilling method and device for coiled tubing provided by the present invention can reduce the reaction torque acting on the coiled tubing string during the drilling process, and avoid the coiled tubing buckling during the coiled tubing drilling process.

Description

A self-balancing torque drilling method and device for coiled tubing

technical field

The invention relates to the field of oil and gas drilling and completion, in particular to a self-balancing torque drilling method and device for coiled tubing.

Background technique

Coiled tubing drilling technology is the main method to tap potential and increase reserves in many oilfields in China in the middle and late stages of development. It uses coiled tubing to replace traditional drill pipe for drilling operations, which has the characteristics of high efficiency, small footprint, low cost, and convenient bottom hole pressure control. The combination of coiled tubing and underbalanced fluid facilitates the realization of continuous circulation and other technical advantages, and can be widely used. Sidetracking in old wells, deepening of old wells and development of unconventional oil and gas reservoirs can improve the recovery of remaining oil and gas, reduce operational risks, and reduce crude oil production costs.

However, because the coiled tubing is prone to buckling when subjected to high torque, conventional coiled tubing drilling operations cannot operate as quickly as conventional drill pipe drilling with high WOB and high torque. Existing conventional coiled tubing drilling operations generally use low WOB and high rotational speed operations, resulting in low drilling efficiency.

In view of this, the inventors have designed a self-balancing torque drilling method and device for coiled tubing based on years of experience in production design in this and related fields, in order to solve the problems in the prior art.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a self-balancing torque drilling method and device for coiled tubing, which can reduce the reaction torque acting on the coiled tubing string during the drilling process and avoid the coiled tubing buckling during the coiled tubing drilling process.

In order to achieve the above object, the present invention proposes a self-balancing torque drilling method for coiled tubing, wherein a connector, a drill pipe, a first drilling unit and a second drilling unit are sequentially connected in series at the end of the coiled tubing, The rotation direction of the first drilling unit is opposite to the rotation direction of the second drilling unit.

The self-balancing torque drilling method for coiled tubing as described above, wherein the first drilling unit includes a first drill bit and a first motor for driving the first drill bit, and the second drilling unit includes A second drill bit and a second motor for driving the second drill bit, the rotation direction of the first motor is opposite to the rotation direction of the second motor.

The present invention also proposes a self-balancing torque drilling device for coiled tubing, which is used in the above-mentioned self-balancing torque drilling method for coiled tubing, wherein the self-balancing torque drilling device includes serially connected coiled tubing. , connector, drill pipe, first drilling unit and second drilling unit, so that the rotation direction of the first drilling unit and the rotation direction of the second drilling unit are opposite to reduce the effect on the drilling process during drilling. Reverse torque on the coiled tubing.

The self-balancing torque drilling device for coiled tubing as described above, wherein the outer diameter of the first drilling unit is larger than the outer diameter of the second drilling unit.

In the above self-balancing torque drilling device for coiled tubing, the first motor is a right-handed screw drilling tool, and the second motor is a left-handed screw drilling tool.

The self-balancing torque drilling device for coiled tubing as described above, wherein the first drill bit has a right-handed cutting structure, the second drill bit has a left-handed cutting structure, and the first motor and the drill pipe pass through the right hand. Screw connection.

In the above self-balancing torque drilling device for coiled tubing, the first motor is a left-handed screw drilling tool, and the second motor is a right-handed screw drilling tool.

The self-balancing torque drilling device for coiled tubing as described above, wherein the first drill bit has a left-handed cutting structure, the second drill bit has a right-handed cutting structure, and the first motor and the drill pipe are left-handed Threaded connection.

The self-balancing torque drilling device for coiled tubing as described above, wherein the first drill bit is a reamer, and the second drill bit is a pilot drill bit.

The self-balancing torque drilling device for coiled tubing as described above, wherein the rotational speed of the second drilling unit is greater than the rotational speed of the first drilling unit.

The self-balancing torque drilling device for coiled tubing as described above, wherein the drill pipe is a weighted drill pipe.

The self-balancing torque drilling device for coiled tubing as described above, wherein the connector comprises a connecting body, a connecting bushing and a plurality of fixing bolts, and the connecting body and the connecting bushing are both cylindrical, The connecting bush is arranged at one end of the connecting body and is sleeved in the connecting body, the outer wall of the connecting bush and the inner wall of the connecting body are spaced apart and form an annular installation space, and the continuous pipe Inserted into the installation space, the outer wall of the connection body is provided with a plurality of installation holes that communicate with the installation space, and the fixing bolts are correspondingly inserted into the installation holes and abut against the continuous pipe On the outer wall of the fixing bolt, the outer wall of the fixing bolt is threadedly matched with the inner wall of the mounting hole, and the other end of the connecting body is threadedly connected with the drill rod.

Compared with the prior art, the present invention has the following features and advantages:

The self-balancing torque drilling method and device for coiled tubing proposed by the present invention utilizes the first drilling unit and the second drilling unit to perform drilling operations at the same time, and during the drilling process, the rotation direction of the first drilling unit is the same as that of the first drilling unit. The rotation direction of the second drilling unit is opposite, in this way, the counter torque generated by the first drilling unit and the counter torque generated by the second drilling unit are also in opposite directions, so that they can cancel each other out, which can greatly reduce the continuous effect of the drilling process. Reverse torque on the pipe string to avoid coiled tubing buckling during high WOB and high torque coiled tubing drilling.

Description of drawings

The drawings described herein are for explanatory purposes only and are not intended to limit the scope of the present disclosure in any way. In addition, the shapes and proportions of the components in the figures are only schematic and are used to help the understanding of the present invention, and do not specifically limit the shapes and proportions of the components of the present invention. Under the teachings of the present invention, those skilled in the art can select various possible shapes and proportions according to specific conditions to implement the present invention.

1 is a schematic structural diagram of a self-balancing torque drilling device for coiled tubing proposed by the present invention;

FIG. 2 is a schematic structural diagram of the connector in the present invention.

Description of reference numbers:

100. Self-balancing torque drilling device; 10. Coiled tubing;

20. Connector; 21. Connection body;

22. Connecting bushings; 23. Fixing bolts;

30. Drill pipe; 40. The first drilling unit;

41. The first drill bit; 42. The first motor;

50. The second drilling unit; 51. The second drill bit;

52. The second motor; 24. The mounting hole.

Detailed ways

The details of the present invention can be more clearly understood with reference to the accompanying drawings and the description of the specific embodiments of the present invention. However, the specific embodiments of the present invention described herein are only for the purpose of explaining the present invention, and should not be construed as limiting the present invention in any way. Under the teaching of the present invention, the skilled person can conceive any possible modifications based on the present invention, and these should be regarded as belonging to the scope of the present invention.

The present invention proposes a self-balancing torque drilling method for coiled tubing. As shown in FIG. 1 , a connector 20, a drill pipe 30, a first drilling unit 40 and a second drill are sequentially connected in series at the end of the coiled tubing 10. For the drilling unit 50, the rotation direction of the first drilling unit 40 and the rotation direction of the second drilling unit 50 are opposite.

The present invention also provides a self-balancing torque drilling device 100 for coiled tubing, the self-balancing torque drilling device 100 includes a coiled tubing 10, a connector 20, a drill pipe 30, a first drilling unit 40 and a first drilling unit 40, which are sequentially connected in series. Two drilling units 50, the rotation direction of the first drilling unit 40 and the rotation direction of the second drilling unit 50 are opposite.

The self-balancing torque drilling method and device for coiled tubing proposed by the present invention utilizes the first drilling unit 40 and the second drilling unit 50 to perform drilling operations at the same time, and during the drilling process, the first drilling unit 40 The rotation direction is opposite to the rotation direction of the second drilling unit 50. In this way, the counter torque generated by the first drilling unit 40 and the counter torque generated by the second drilling unit 50 are also in opposite directions, which can cancel each other out and greatly reduce the The reaction torque acting on the coiled tubing string during the drilling process prevents the coiled tubing from buckling during high WOB and high torque coiled tubing drilling.

In an optional example of the present invention, the rotational speed of the second drilling unit 50 is higher than the rotational speed of the first drilling unit 40 to further ensure efficient operation.

In an optional example of the present invention, the first drilling unit 40 includes a first drill bit 41 and a first motor 42 for driving the first drill bit 41 to rotate, and the second drilling unit 50 includes a second drill bit 51 and a first motor 42 for driving the first drill bit 41 to rotate. The second motor 52 for driving the second drill bit 52 to rotate, the rotation direction of the first motor 42 is opposite to the rotation direction of the second motor 52 .

In an optional example of the present invention, the first drill bit 41 is a reamer, and the second drill bit 51 is a pilot drill bit.

Further, the first drill bit 41 can be a fixed wing reamer, and one end of the fixed wing reamer is processed with a male thread for connecting with the first motor 42 , and the other end is processed with a female thread for connecting with the second motor 52 . thread. Of course, the first drill bit 41 is not limited to be fixed with a reamer, and those skilled in the art can choose other types of reamers available.

Further, the outer diameter of the first drill bit 41 is larger than the outer diameter of the second drill bit 51 . Preferably, the outer diameter of the first drill bit 41 is 120 mm, and the outer diameter of the second drill bit 51 is 89 mm.

In an optional example, as shown in FIG. 1 , the first motor 42 is a right-hand screw drilling tool, the outer diameter of the first motor 42 is 95 mm, and the rated speed is 150 rpm; the second motor 52 is a left-handed screw drilling tool, and the second motor 52 is a left-handed screw drilling tool. The outer diameter of the motor 52 is 73 mm, and the rated rotational speed is 150 rpm.

Preferably, the first drill bit 41 has a right-handed cutting structure, and the second drill bit 51 has a left-handed cutting structure.

Preferably, the first motor 42 is connected with the drill rod 30 through a right-hand thread, so as to ensure the firmness of the screw connection between the first motor 42 and the drill rod 30 during the drilling process.

In this embodiment, as shown in FIG. 1 , when drilling, the first motor 42 drives the first drill bit 41 (reamer) to rotate clockwise to break the rock, generating counter-torque to the left; the second motor 52 drives the second The drill bit 51 (pilot bit) rotates left-handedly to break the rock, and generates a right-handed counter-torque. Two counter-torques in opposite directions cancel each other, which can greatly reduce the counter-torque on the coiled tubing string during drilling and avoid coiled tubing buckling during high WOB and high torque coiled tubing drilling.

In another optional example of the present invention, the first motor 42 is a left-handed screw drilling tool, and the second motor 52 is a right-handed screw drilling tool.

Preferably, the first drill bit 41 has a left-handed cutting structure, and the second drill bit 51 has a right-handed cutting structure.

Preferably, the first motor 42 is connected with the drill rod 30 through a left-hand thread.

During drilling, the first motor 42 drives the first drill bit 41 (reamer) to rotate left-handed to break the rock, generating a counter-torque of right-hand rotation; the second motor 52 drives the second drill bit 51 (pilot bit) to rotate to the right to break the rock , resulting in a left-handed counter-torque. Two counter-torques in opposite directions cancel each other, which can greatly reduce the counter-torque on the coiled tubing string during drilling and avoid coiled tubing buckling during high WOB and high torque coiled tubing drilling.

In an optional example of the present invention, the drill rod 30 is a weighted drill rod. The main function of the drill pipe 30 is to provide the WOB, which is a key parameter for drilling. The weighted drill pipe can withstand higher WOB, which further ensures the smooth progress of high WOB and high torque drilling operations. The structure of the weighted drill pipe may adopt the prior art, which will not be repeated here.

In an optional example of the present invention, as shown in FIG. 2 , the connector 20 includes a connecting body 21 , a connecting bush 22 and a plurality of fixing bolts 23 . The connecting body 21 and the connecting bush 22 are both cylindrical and connected to The bushing 22 is arranged at one end of the connecting body 21 and is sleeved in the connecting body 21. There is an interval between the outer wall of the connecting bushing 22 and the inner wall of the connecting body 21 to form an annular installation space. The continuous pipe 10 is inserted in the above-mentioned installation. In the space, the outer wall of the connecting body 21 is provided with a plurality of installation holes 24 which communicate with the installation space. The fixing bolts 23 are correspondingly inserted into the installation holes 24 and abut against the outer wall of the continuous pipe 10. The inner wall of the mounting hole 14 is threadedly engaged, and the other end of the connecting body 21 is threadedly engaged with the drill rod 30 .

In an optional example, the outer diameter of the connecting body 21 is 102 mm, the outer wall of one end of the connecting body 21 is machined with a plurality of mounting holes 24 , and the other end of the connecting body 21 is machined with male threads that can be connected with the drill rod 30 . The outer wall of the connection bushing 22 is machined with a circular concave; one end of the fixing bolt 23 is machined with an external thread, and the other end of the fixing bolt 23 is machined with a spherical protrusion, which can abut against the outer wall of the coiled pipe 10 .

Now take a 2 7/8" coiled tubing drilling as an example to describe the self-balancing torque drilling method and device for coiled tubing proposed by the present invention in detail:

First, assemble the tool string at the wellhead: the second drill bit 51 is connected with the second motor 52 by the thread; the second motor 52 is connected with the first drill bit 41 by the thread; the first drill bit 41 is connected with the first motor 42 by the thread; the first motor 42 is threadedly connected to the drill rod 30; the drill rod 30 is threadedly connected to the connecting body 21 of the connector 20; , the continuous tube 10 is fixed by radial extrusion through the fixing bolts 23 .

As shown in FIG. 1 , the first motor 42 is a right-handed screw drill, the first drill bit 41 is a reamer, the second motor 52 is a left-handed screw drill, and the second drill bit 51 is a pilot bit.

After that, the self-balancing torque drilling device 100 is lowered into the well and drilling starts. During the drilling process, first, the first motor 42 drives the first drill bit 41 to rotate clockwise to break the rock, and generate counter-torque to the left; in the first drilling unit 40 After drilling for a period of time, a hole is formed in the ground; after that, the second drilling unit 50 is lowered into the hole, and the second motor 52 drives the second drill bit 51 to rotate left-handed, because the outer diameter of the second drill bit 51 is larger than that of the first drill bit 41 The outer diameter of the second drill bit 51 acts on the inner wall of the hole to expand the inner diameter of the hole. As the second drill bit 51 rotates to the left to break the rock, a counter-torque to the right is generated. Two counter-torques in opposite directions cancel each other, which can greatly reduce the counter-torque on the coiled tubing string during drilling and avoid coiled tubing buckling during high WOB and high torque coiled tubing drilling.

The purpose of the detailed explanations for the above-mentioned embodiments is only to explain the present invention so that the present invention can be better understood. However, these descriptions should not be construed to limit the present invention for any reason, especially in different The various features described in the embodiments can also be arbitrarily combined with each other to form other embodiments, unless there is an explicit description to the contrary, these features should be understood as being applicable to any embodiment, and not limited to the described implementation. Way.

Claims (12)

1. A self-balancing torque drilling method for coiled tubing is characterized in that a connector, a drill rod, a first drilling unit and a second drilling unit are sequentially connected in series at the tail end of the coiled tubing, and the rotation direction of the first drilling unit is opposite to that of the second drilling unit so as to reduce reactive torque acting on the coiled tubing during drilling.

2. The method of self-balancing torque drilling for coiled tubing of claim 1, wherein the first drilling unit has an outer diameter greater than an outer diameter of the second drilling unit.

3. A self-balancing torque drilling apparatus for coiled tubing for use in the self-balancing torque drilling method for coiled tubing of claim 1 or 2, wherein the self-balancing torque drilling apparatus comprises a coiled tubing, a connector, a drill pipe, a first drilling unit and a second drilling unit connected in series in that order, the direction of rotation of the first drilling unit and the direction of rotation of the second drilling unit being opposite.

4. The self-balancing torque drilling apparatus for coiled tubing of claim 3, wherein the first drilling unit comprises a first drill bit and a first motor for driving the first drill bit, and the second drilling unit comprises a second drill bit and a second motor for driving the second drill bit, the first motor rotating in a direction opposite to the second motor.

5. The self-balancing torque drilling apparatus for coiled tubing of claim 4, wherein the first motor is a right-handed screw drill and the second motor is a left-handed screw drill.

6. The self-balancing torque drilling apparatus for coiled tubing of claim 5, wherein the first drill bit has a right-handed cutting configuration and the second drill bit has a left-handed cutting configuration, the first motor being coupled to the drill pipe via right-handed threads.

7. The self-balancing torque drilling apparatus for coiled tubing of claim 4, wherein the first motor is a left-hand screw drill and the second motor is a right-hand screw drill.

8. The self-balancing torque drilling apparatus for coiled tubing of claim 7, wherein the first drill bit has a left-handed cutting configuration and the second drill bit has a right-handed cutting configuration, the first motor being coupled to the drill pipe via left-handed threads.

9. The self-balancing torque drilling apparatus for coiled tubing of claim 4, wherein the first drill bit is a reamer and the second drill bit is a pilot drill bit.

10. The self-balancing torque drilling apparatus for coiled tubing of claim 3, wherein the rotational speed of the second drilling unit is greater than the rotational speed of the first drilling unit.

11. The self-balancing torque drilling apparatus for coiled tubing of claim 3, wherein the drill pipe is a weighted drill pipe.

12. The self-balancing torque drilling apparatus for coiled tubing of claim 3, the connector comprises a connecting body, a connecting bush and a plurality of fixing bolts, wherein the connecting body and the connecting bush are cylindrical, the connecting bushing is arranged at one end of the connecting body and sleeved in the connecting body, a space is arranged between the outer wall of the connecting bushing and the inner wall of the connecting body, and an annular mounting space is formed, the continuous pipe is inserted in the installation space, a plurality of installation holes communicated with the installation space are arranged on the outer wall of the connecting body, the fixing bolt is correspondingly inserted into the mounting hole and abuts against the outer wall of the continuous pipe, the outer wall of the fixing bolt is in threaded fit with the inner wall of the mounting hole, and the other end of the connecting body is in threaded connection with the drill rod.

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