Magnetic drag reduction tool for coiled tubing

Abstract

The present invention relates to the field of downhole operation technology and is a magnetic drag reduction tool for continuous oil pipes, comprising a magnetic drag reduction body, a positioning magnet, a roller, a roller shaft, and a snap-fit ​​device. The outer side of the upper end of the magnetic drag reduction body is provided with at least two mounting grooves with openings facing upward, each mounting groove is provided with a positioning magnet, with the N-level positioning magnet facing outward and the S-level positioning magnet facing inward; a central channel running vertically through the middle of the magnetic drag reduction body is provided, and a snap-fit ​​device capable of snapping into the outer wall of the continuous oil pipe is provided on the inner side of the magnetic drag reduction body. The present invention has a reasonable and compact structure and is easy to use. By providing a roller, the centering of the continuous oil pipe in the horizontal section of the downhole is improved, so that the continuous oil pipe cannot be tightly attached to the pipe wall, and the surface contact is changed to a point contact state to reduce the friction resistance during lowering; by providing an upper slip and a lower slip, the magnetic drag reduction body is prevented from sliding on the outer side of the continuous oil pipe during lowering, and has the characteristics of stability, high efficiency, and low friction resistance.

Description

Technical Field

[0001] The invention relates to the technical field of downhole operations and is a magnetic drag reduction tool for continuous oil pipes. Background Art

[0002] In recent years, the scale of coiled tubing operations in horizontal wells has increased significantly. However, due to the inherent flexibility of the coiled tubing, it is prone to bending and frictional locking within the wellbore. This, coupled with the irregularities of the wellbore, can easily lead to difficulty in lowering the tubing string during long horizontal sections, and even cause it to self-lock, preventing it from being lowered to the intended depth for subsequent operations. This has a certain impact on the efficient and low-cost development of the oilfield. Currently, the traditional solution is to design hydraulic oscillators into the tubing string and add metallic drag reducers to the well killing fluid to delay the occurrence of "self-locking". However, the effectiveness of hydraulic oscillators and metallic drag reducers is limited and they cannot be used in operations such as perforating, fracturing, and logging that do not require circulation conditions. As a result, existing technologies are no longer able to meet field needs. Summary of the Invention

[0003] The present invention provides a magnetic drag reduction tool for coiled tubing, which overcomes the above-mentioned shortcomings of the prior art and can effectively solve the problem of difficulty in lowering the tubing string during operation of a long horizontal section of the prior coiled tubing.

[0004] The technical solution of the present invention is achieved through the following measures: a magnetic drag reduction tool for a continuous oil pipe includes a magnetic drag reduction body, a positioning magnet, a roller, a roller shaft, and a bite device. The outer side of the upper end of the magnetic drag reduction body is provided with at least two installation grooves with openings facing upward, and each installation groove is provided with a positioning magnet, the N level of the positioning magnet faces outward, and the S level of the positioning magnet faces inward; a central channel is provided in the middle of the magnetic drag reduction body, which runs through the upper and lower parts, and a bite device is provided on the inner side of the magnetic drag reduction body that can bite the outer wall of the continuous oil pipe. At least four installation square holes are provided on the outer side of the magnetic drag reduction body, and each installation square hole is provided with a roller whose outer end is located on the outer side of the magnetic drag reduction body, and each roller is provided with a roller shaft fixedly installed at the corresponding position of the magnetic drag reduction body on the inner side; the magnetic drag reduction body includes a front body, a rear body and a fixing device, one side of the front body is hinged to one side of the rear body, and the other side of the front body is detachably fixed to the other side of the rear body by a fixing device.

[0005] The following are further optimizations and / or improvements to the above technical solutions:

[0006] The above-mentioned engaging device may include an upper cava and a lower cava, and the central channel includes an upper straight hole, an upper conical hole, a lower conical hole and a lower straight hole connected in sequence from top to bottom. The upper conical hole is a frustum hole that is small at the top and large at the bottom, and the lower conical hole is a frustum hole that is large at the top and small at the bottom. An upper cava is provided on the inside of the magnetic drag reduction body corresponding to the position of the upper conical hole, and a lower cava is provided on the inside of the magnetic drag reduction body corresponding to the position of the lower conical hole.

[0007] The outer side of the upper portion of the magnetic drag reduction body corresponding to the upper straight hole position may have four mounting square holes evenly distributed along the circumference, and the outer side of the lower portion of the magnetic drag reduction body corresponding to the lower straight hole position may have four mounting square holes evenly distributed along the circumference.

[0008] The outer side of the upper end of the magnetic drag reduction body may be evenly spaced along the circumference with six installation grooves with openings facing upward.

[0009] The fixing device may be two fixing screws spaced apart from each other.

[0010] The magnetic drag reduction body may further include a pin, and one side of the front body and one side of the rear body are hinged together through the pin.

[0011] The mounting groove may be a dovetail groove that is wider inside and narrower outside.

[0012] The present invention has a reasonable and compact structure and is easy to use. By arranging rollers, the centering of the coiled tubing in the horizontal section of the downhole is improved, so that the coiled tubing cannot be tightly attached to the pipe wall, and the surface contact is changed to a point contact state, thereby reducing the friction resistance during lowering. By arranging a detachable front body and a rear body that are fixedly installed together, it is convenient to install the magnetic drag reduction body on the outside of the coiled tubing. By arranging upper and lower slips, the magnetic drag reduction body is prevented from sliding on the outside of the coiled tubing during the lowering process, and has the characteristics of stability, high efficiency and low friction resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Attachment Figure 1 It is a schematic diagram of the main structure of the best embodiment of the present invention.

[0014] Attachment Figure 2 For attachment Figure 1 Schematic diagram of the cross-sectional structure at AA.

[0015] Attachment Figure 3 For attachment Figure 1 Schematic diagram of the left half-section structure.

[0016] Attachment Figure 4 For attachment Figure 3 Schematic diagram of the cross-sectional structure at BB.

[0017] Attachment Figure 5 For attachment Figure 1 Schematic diagram of the three-dimensional structure.

[0018] The codes in the accompanying drawings are: 1 for the front body, 2 for the rear body, 3 for the roller, 4 for the roller shaft, 5 for the mounting square hole, 6 for the mounting slot, 7 for the pin shaft, 8 for the upper cava, 9 for the lower cava, 10 for the upper straight hole, 11 for the upper tapered hole, 12 for the lower tapered hole, 13 for the lower straight hole, and 14 for the fixing screw. DETAILED DESCRIPTION

[0019] The present invention is not limited to the following embodiments, and specific implementation methods can be determined based on the technical solutions of the present invention and actual conditions.

[0020] In the present invention, for the convenience of description, the relative position relationship of each component is described based on the Figure 1 For example, the positional relationships of front, back, up, down, left, and right are determined according to the layout directions of the drawings in the specification.

[0021] The present invention will be further described below in conjunction with the embodiments and accompanying drawings:

[0022] As attached Figure 1 、 2 As shown in Figures 3, 4, and 5, the magnetic drag reduction tool for a continuous oil pipe includes a magnetic drag reduction body, a positioning magnet, a roller 3, a roller shaft 4, and a biting device. The outer side of the upper end of the magnetic drag reduction body is provided with at least two mounting grooves 6 with openings facing upward, and each mounting groove 6 is provided with a positioning magnet, the N level of the positioning magnet faces outward, and the S level of the positioning magnet faces inward; a central channel is provided in the middle of the magnetic drag reduction body, and a biting device that can bite the outer wall of the continuous oil pipe is provided on the inner side of the magnetic drag reduction body. At least four mounting square holes 5 that pass through inside and outside are provided on the outer side of the magnetic drag reduction body, and each mounting square hole 5 is provided with a roller 3 whose outer end is located on the outside of the magnetic drag reduction body, and each roller 3 is provided with a roller shaft 4 fixedly installed at the corresponding position of the magnetic drag reduction body on the inner side; the magnetic drag reduction body includes a front body 1, a rear body 2 and a fixing device, one side of the front body 1 is hinged to one side of the rear body 2, and the other side of the front body 1 is detachably fixed to the other side of the rear body 2 by a fixing device. During use, the roller 3 is provided to improve the centering of the coiled tubing in the horizontal section of the downhole well, so that the coiled tubing cannot be tightly attached to the pipe wall, and the surface contact is changed to a point contact state, thereby reducing the friction resistance during lowering; the front body 1 and the rear body 2 that are detachably fixed together are provided to facilitate the installation of the magnetic drag reduction body on the outside of the coiled tubing; the bite device is provided to prevent the magnetic drag reduction body from sliding on the outside of the coiled tubing during the lowering process; and the positioning magnet is provided to facilitate the wellhead magnetic detection device to detect and quickly locate the downhole tool when it comes out of the well.

[0023] The above-mentioned magnetic drag reduction tool for coiled tubing can be further optimized and / or improved according to actual needs:

[0024] As attached Figure 1 、 2As shown in Figures 3, 4, and 5, the engaging device includes upper slips 8 and lower slips 9. The central channel includes an upper straight hole 10, an upper tapered hole 11, a lower tapered hole 12, and a lower straight hole 13, which are connected in sequence from top to bottom. The upper tapered hole 11 is a frustum with a smaller top and a larger bottom, while the lower tapered hole 12 is a frustum with a larger top and a smaller bottom. An upper slip 8 is provided on the inner side of the magnetic drag reduction body corresponding to the position of the upper tapered hole 11, and a lower slip 9 is provided on the inner side of the magnetic drag reduction body corresponding to the position of the lower tapered hole 12. During use, the upper slips 8 and lower slips 9 prevent the magnetic drag reduction body from sliding on the outside of the coiled tubing during lowering.

[0025] As attached Figure 1 、 2 As shown in Figures 3, 4 and 5, four mounting square holes 5 are evenly distributed along the circumference on the outer side of the upper portion of the magnetic drag reduction body corresponding to the position of the upper straight hole 10, and four mounting square holes 5 are evenly distributed along the circumference on the outer side of the lower portion of the magnetic drag reduction body corresponding to the position of the lower straight hole 13. During use, such an arrangement changes the surface contact into a point contact state to reduce the friction resistance during lowering and enhance the stability of the lowering of the present invention. According to needs, the four mounting square holes 5 on the outer side of the upper portion of the magnetic drag reduction body can be arranged one above and one below, such as the mounting square holes 5 at the 0° position and the 180° position are at the same vertical height and are above the mounting square holes 5 at the 90° and 270° positions, and the four mounting square holes 5 on the outer side of the lower portion of the magnetic drag reduction body are arranged similarly; in addition, the roller 3 and the roller shaft 4 must be specially treated to increase their service life and make the tool reusable. After the operation is completed, only simple inspection and maintenance work needs to be performed on them to minimize the cost of use.

[0026] As attached Figure 1 、 2 As shown in Figures 3, 4 and 5, six mounting grooves 6 with upward openings are evenly distributed along the circumference of the outer side of the upper end of the magnetic drag reduction body. During use, such an arrangement enhances the stability of the wellhead detection device.

[0027] As attached Figure 1 、 2 As shown in Figures 3, 4, and 5, the fixing device comprises two fixing screws 14 spaced apart from one another. During use, the fixing screws 14 allow the front body 1 and the rear body 2 to be removably fixed together. By tightening the fixing screws 14, the conical surfaces of the upper tapered hole 11 and the lower tapered hole 12 act on the upper slips 8 and the lower slips 9, respectively, causing the engaging device to engage the coiled tubing, preventing the magnetic drag reduction body from sliding on the outside of the coiled tubing during lowering.

[0028] As attached Figure 1 、 2As shown in Figures 3, 4 and 5, the magnetic drag reducing body further includes a pin 7, and one side of the front body 1 and one side of the rear body 2 are hinged together through the pin 7. During use, such an arrangement facilitates the installation of the magnetic drag reducing body on the outside of the coiled tubing.

[0029] As attached Figure 1 、 2 As shown in Figures 3, 4 and 5, the mounting groove 6 is a dovetail groove that is wide inside and narrow outside. During use, the dovetail groove is provided to facilitate the positioning of the magnet embedded in the dovetail groove.

[0030] The above technical features constitute the best embodiment of the present invention, which has strong adaptability and best implementation effect. Non-essential technical features can be added or removed according to actual needs to meet the requirements of different situations.

Claims

1. A magnetic drag reduction tool for coiled tubing, characterized in that It includes a magnetic drag reduction body, a positioning magnet, a roller, a roller shaft, and a biting device. The outer side of the upper end of the magnetic drag reduction body is provided with at least two mounting grooves with openings facing upward, and each mounting groove is provided with a positioning magnet, with the N level of the positioning magnet facing outward and the S level of the positioning magnet facing inward; a central channel running through the upper and lower parts is provided in the middle of the magnetic drag reduction body, and a biting device capable of biting the outer wall of the continuous oil pipe is provided on the inner side of the magnetic drag reduction body; at least four mounting square holes running through the outside and inside are provided on the outer side of the magnetic drag reduction body, and a roller with the outer end located on the outside of the magnetic drag reduction body is provided in each mounting square hole, and a roller shaft fixedly installed at the corresponding position of the magnetic drag reduction body is provided on the inner side of each roller; the magnetic drag reduction body includes a front body, a rear body and a fixing device, one side of the front body is hinged to one side of the rear body, and the other side of the front body is detachably fixed to the other side of the rear body by a fixing device; The engaging device includes an upper slip and a lower slip, and the central channel includes an upper straight hole, an upper conical hole, a lower conical hole and a lower straight hole connected in sequence from top to bottom. The upper conical hole is a frustum hole that is small at the top and large at the bottom, and the lower conical hole is a frustum hole that is large at the top and small at the bottom. An upper slip is provided on the inside of the magnetic drag reduction body corresponding to the position of the upper conical hole, and a lower slip is provided on the inside of the magnetic drag reduction body corresponding to the position of the lower conical hole.

2. The magnetic drag reduction tool for coiled tubing according to claim 1, characterized in that Four mounting square holes are evenly distributed along the circumference on the outer side of the upper part of the magnetic drag reduction body corresponding to the upper straight hole position, and four mounting square holes are evenly distributed along the circumference on the outer side of the lower part of the magnetic drag reduction body corresponding to the lower straight hole position.

3. The magnetic drag reduction tool for coiled tubing according to claim 1 or 2, characterized in that Six mounting grooves with upward openings are evenly distributed along the circumference on the outer side of the upper end of the magnetic drag reduction body.

4. The magnetic drag reduction tool for coiled tubing according to claim 1 or 2, characterized in that The fixing device is two fixing screws arranged at intervals up and down.

5. The magnetic drag reduction tool for coiled tubing according to claim 3, characterized in that The fixing device is two fixing screws arranged at intervals up and down.

6. The magnetic drag reduction tool for coiled tubing according to claim 1, 2 or 5, characterized in that The magnetic drag reduction body also includes a pin shaft, and one side of the front body and one side of the rear body are hinged together through the pin shaft.

7. The magnetic drag reduction tool for coiled tubing according to claim 3, characterized in that The magnetic drag reduction body also includes a pin shaft, and one side of the front body and one side of the rear body are hinged together through the pin shaft.

8. The magnetic drag reduction tool for coiled tubing according to claim 4, characterized in that The magnetic drag reduction body also includes a pin shaft, and one side of the front body and one side of the rear body are hinged together through the pin shaft.

9. The magnetic drag reduction tool for coiled tubing according to claim 1, 2, 5, 7 or 8, characterized in that The mounting groove is a dovetail groove that is wide inside and narrow outside.

10. The magnetic drag reduction tool for coiled tubing according to claim 6, characterized in that The mounting groove is a dovetail groove that is wide inside and narrow outside.

Images