Paraffin removal tool

Abstract

The utility model belongs to the technical field of petroleum drilling and production equipment, and particularly relates to a paraffin removal tool. The paraffin removal tool comprises a center rod and a paraffin scraping piece arranged outside the center rod in a sleeving mode, the paraffin scraping piece comprises a dewaxing section, a first scraping section and a second scraping section, the first scraping section and the second scraping section are connected to the two opposite ends of the dewaxing section, and a dewaxing structure is arranged on the dewaxing section and comprises a dewaxing groove. The de-waxing structure further comprises an S-shaped opening which is formed in the de-waxing section relative to the de-waxing groove, longitudinally penetrates through the de-waxing groove and is used for generating torque. When paraffin in the paraffin scraping sheet is extruded and discharged through an S-shaped opening which is formed in the paraffin discharging section and extends in the axial direction of the center rod, the S-shaped opening can enable the paraffin entering an inner channel of the paraffin scraping sheet to be discharged in different directions in the extending direction of the S-shaped opening, so that torque enabling the paraffin scraping sheet to rotate is generated, and the paraffin scraping sheet moves up and down in a matched mode; the rotating capacity of the paraffin scraping blade is enhanced, the resistance for discharging paraffin is reduced, paraffin accumulation is effectively avoided, and the paraffin scraping effect is further improved.

Description

Technical Field

[0001] The utility model belongs to the technical field of petroleum drilling equipment, and in particular relates to a wax cleaning tool. Background Art

[0002] During the production process of oil wells, as the temperature and pressure decrease and the gas precipitates, when certain conditions are met, the paraffin dissolved in the crude oil will crystallize, precipitate, and adhere to the inner wall of the production string. If there is too much paraffin attached to the inner wall of the production string, it will increase the oil flow resistance, causing the production string to be blocked, thus causing the oil well to stop production or reduce production. In order to avoid the above problems, wax cleaning tools are often used during the production process to clean the paraffin in the production string to reduce the oil flow resistance in the oil pipe and increase the oil well production.

[0003] The Chinese utility model patent with authorization announcement number CN211201882U and authorization announcement date August 7, 2020 discloses a mechanical wax scraper, including a first shaft, a second shaft (i.e., a center rod), and a limit joint (i.e., a limit part) whose two ends are detachably connected to one end of the first shaft and the second shaft; two rotating support shafts (i.e., connecting sleeves), one end of which is rotatably arranged on the first shaft and the second shaft respectively; a cleaning scraper (i.e., a wax scraper blade) is sleeved on the outside of the first shaft and the second shaft, one side of the cleaning scraper is an open side, and a guide port is provided on the side corresponding to the open side, and the two ends of the open side extend outward to form a blade (i.e., a first blade portion and a second blade portion); the other end of the rotating support shaft is detachably connected to the blade respectively; it also includes a first joint connected to the other end of the first shaft and a salvage head connected to the other end of the second shaft.

[0004] A Chinese utility model patent with authorization announcement number CN207568560U and authorization announcement date July 3, 2018 discloses a wax scraping device, including a center rod, a wax scraping sheet mounted on the center rod, and a weighting rod arranged at the bottom end of the center rod, and the top of the center rod is connected to a ground winch by a steel wire; the wax scraping sheet includes a first sharp arc-shaped end portion (i.e., a first blade portion), a tubular body (i.e., a wax removal section), and a second sharp arc-shaped end portion (i.e., a second blade portion) connected in sequence from top to bottom, wherein a vertical opening is axially arranged on the side wall of the tubular body, and an arc groove is arranged on the side wall of the tubular body opposite to the opening; an upper shaft sleeve (i.e., a connecting sleeve) and a lower shaft sleeve (i.e., a connecting sleeve) are respectively arranged on the inner side walls of the first sharp arc-shaped end portion and the second sharp arc-shaped end portion, and the upper shaft sleeve and the lower shaft sleeve can be rotatably mounted on the center rod.

[0005] However, in the above scheme, when the scraped paraffin is discharged through the vertical opening or the guide port during the up and down movement of the wax scraper, the discharge direction is single, and there is a risk of large discharge resistance; at the same time, the wax scraper rotates only through the contact between the wax scraper and the paraffin, and there is a problem of insufficient rotation of the wax scraper, resulting in poor scraping effect. Utility Model Content

[0006] The utility model aims to provide a wax cleaning tool to solve the problem in the prior art that the wax cleaning tool only contacts the wax through a wax scraper, which results in insufficient rotation of the wax scraper and causes poor wax scraping effect.

[0007] In order to achieve the above purpose, the wax cleaning tool in the utility model adopts the following technical solutions:

[0008] A wax cleaning tool comprises a center rod and a wax scraper sleeved on the outside of the center rod, the wax scraper comprises a wax removal section and a first scraping section and a second scraping section connected to opposite ends of the wax removal section, the wax removal section is provided with a wax removal structure, the wax removal structure comprises a wax removal groove, the wax removal structure also comprises an S-shaped opening which is longitudinally penetrated and arranged on the wax removal section relative to the wax removal groove and is used to generate torque.

[0009] Furthermore, an angle is formed between the tangent direction of the S-shaped opening and the axial direction of the center rod.

[0010] Furthermore, the wax scraper blade is a cylindrical through-diameter structure, and the central axis of the central rod is located on the side of the central axis of the wax scraper blade away from the S-shaped opening.

[0011] Furthermore, the wax removal groove is a trapezoidal groove.

[0012] Furthermore, the first scraping segment is provided with a first blade portion, and the second scraping segment is provided with a second blade portion, the first blade portion and the second blade portion both form an angle with the axial direction of the center rod, and the inclination direction of the first blade portion relative to the center rod is opposite to the inclination direction of the second blade portion relative to the center rod.

[0013] Furthermore, the first scraping segment and the second scraping segment are respectively provided with connecting sleeves rotatably connected to the central rod.

[0014] Furthermore, a limiting portion for limiting the axial movement of the wax scraper blade is fixedly provided on the central rod.

[0015] Furthermore, the limiting portion is arranged between the two connecting sleeves.

[0016] Furthermore, the limiting portion is an annular protrusion convexly provided on the central rod.

[0017] Furthermore, the opposite ends of the central rod are respectively connected with an upper joint for connecting to a wire rope cap and a lower joint for connecting to a weighting rod through threads.

[0018] The beneficial effects of the utility model are as follows: the utility model is improved based on the prior art, when the paraffin in the wax scraper is squeezed and discharged through the S-shaped opening arranged on the wax discharge section and extending axially along the center rod, the S-shaped opening can make the paraffin entering the internal channel of the wax scraper be discharged in different directions along the extension direction of the S-shaped opening, thereby generating a torque to rotate the wax scraper, and cooperating with the up and down movement of the wax scraper, the rotation ability of the wax scraper is enhanced, thereby improving the wax scraping effect; in addition, the axially extending S-shaped opening can increase the length of the opening under the limited space of the wax scraper, and when the paraffin in the wax scraper is squeezed and emerges through the S-shaped opening, the paraffin can be cut off at the transition point of the S-shaped opening curve, so that the paraffin falls off from the S-shaped opening, thereby avoiding paraffin clogging at the opening; at the same time, the S-shaped opening is conducive to dispersing the extrusion force borne by the wax discharge section, avoiding unidirectional deformation of the wax scraper during operation, reducing the resistance to paraffin discharge, and effectively avoiding paraffin accumulation. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 Schematic diagram of the wax cleaning tool structure in the wax cleaning tool embodiment of the utility model;

[0020] Figure 2 for Figure 1 Partial top view after removing the center rod;

[0021] Figure 3 A schematic diagram of the structure of a wax scraper in an embodiment of a wax cleaning tool in the utility model.

[0022] In the figure: 1. center rod; 11. upper joint; 12. lower joint; 13. limit part; 2. wax scraper; 21. connecting sleeve; 22. scraping part; 221. wax removal section; 222. first scraping section; 2221. first blade; 223. second scraping section; 2231. second blade; 224. wax removal groove; 225. S-shaped opening; 3. wire rope cap; 4. weighting rod. DETAILED DESCRIPTION

[0023] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0024] The wax cleaning tool provided by the utility model provides an S-shaped opening extending axially along the center rod on the wax discharge section of the wax scraper blade. When the paraffin in the wax scraper blade is squeezed and discharged through the S-shaped opening, the S-shaped opening can enable the paraffin that has entered the internal channel of the wax scraper blade to be discharged in different directions along the extension direction of the S-shaped opening, thereby generating a torque to rotate the wax scraper blade, which cooperates with the up and down movement of the wax scraper blade to enhance the rotation ability of the wax scraper blade, thereby improving the wax scraping effect. At the same time, the S-shaped opening is conducive to dispersing the extrusion force borne by the wax discharge section, avoiding unidirectional deformation of the wax scraper blade during operation, reducing the resistance to paraffin discharge, and effectively avoiding paraffin accumulation.

[0025] Embodiment of the wax removal tool in the utility model:

[0026] like Figure 1 and Figure 3 As shown, this embodiment provides a wax cleaning tool, including a center rod 1 and a wax scraper 2 connected to the center rod 1, the wax scraper 2 includes a scraping portion 22 sleeved on the outside of the center rod 1, the scraping portion 22 includes a wax removal segment 221 and a first scraping segment 222 and a second scraping segment 223 connected to the opposite ends of the wax removal segment 221, and a wax removal structure is provided on the wax removal segment 221.

[0027] In this embodiment, the scraping portion 22 is a hollow cylindrical structure, the first scraping section 222 is provided with a first blade 2221 for scraping paraffin, and the second scraping section 223 is provided with a second blade 2231 for scraping paraffin. The first blade 2221 and the second blade 2231 both form an angle with the axial direction of the center rod 1, and the inclination direction of the first blade 2221 relative to the center rod 1 and the inclination direction of the second blade 2231 relative to the center rod 1 are opposite; specifically, the first blade 2221 and the second blade 2231 are similar to an "eight"-shaped structure as a whole. After the wax scraper 2 with a hollow cylindrical structure performs the wax scraping operation, the wax scraps produced by scraping will be squeezed out by the wax discharge structure arranged on the wax discharge section 221, thereby preventing the internal channel of the scraping section 22 from being blocked; the first blade 2221 and the second blade 2231 with opposite inclined directions enable the wax scraper 2 to have the ability to scrape wax in both directions. Even if the first blade 2221 is not scraped clean, it can be scraped again by the second blade 2231. The reciprocating motion of the wax scraper 2 effectively ensures the wax scraping effect, thereby achieving the effect of clearing wax and unblocking; the first blade 2221 and the second blade 2231 both form an angle with the axial direction of the center rod 1, which can effectively ensure that the wax scraper 2 rotates after the first blade 2221 and the second blade 2231 contact the paraffin on the inner wall of the pipe column, thereby ensuring the wax scraping effect of the wax scraper 2.

[0028] In order to improve the wax scraping effect, in this embodiment, the first blade 2221 and the second blade 2231 have an annular tongue-shaped structure that matches the curvature of the inner wall of the oil pipe. This effectively increases the pressure when the first blade 2221 and the second blade 2231 contact the wax block, and enhances the cutting ability of the scraping part 22; at the same time, when encountering obstacles, the force of the wax scraping blade 2 can be more evenly applied.

[0029] In this embodiment, the wax removal structure includes an S-shaped opening 225 extending axially and used to generate torque on the scraping portion 22. Specifically, the side wall of the wax removal section 221 is provided with an S-shaped opening 225 extending axially. When the paraffin in the wax scraper 2 is squeezed and discharged through the S-shaped opening 225 extending axially on the wax discharge section 221, the S-shaped opening 225 can make the paraffin entering the internal channel of the wax scraper 2 be discharged in different directions along the extension direction of the S-shaped opening 225, thereby generating a torque that causes the wax scraper 2 to rotate, and cooperates with the up and down movement of the wax scraper 2 to enhance the rotation ability of the wax scraper 2, thereby improving the wax scraping effect; in addition, the axially extending S-shaped opening 225 can increase the length of the opening under the limited space of the wax scraper 2, and when the paraffin in the wax scraper 2 is squeezed and discharged through the S-shaped opening 225, the paraffin can be cut off at the transition point of the curve of the S-shaped opening 225, so that the paraffin falls off from the S-shaped opening 225, thereby avoiding paraffin clogging at the opening; at the same time, the S-shaped opening 225 is conducive to dispersing the extrusion force borne by the wax discharge section 221, avoiding unidirectional deformation of the wax scraper 2 during operation, reducing the resistance to paraffin discharge, and effectively avoiding paraffin accumulation.

[0030] In this embodiment, there is an angle between the tangent direction of the S-shaped opening 225 and the axial direction of the center rod 1. Thus, the torque for rotating the wax scraper 2 when the S-shaped opening 225 discharges wax can be enhanced.

[0031] In order to further improve the wax scraping effect, the wax removal structure also includes a wax removal groove 224 arranged on the scraping portion 22 relative to the S-shaped opening 225. Specifically, the wax removal groove 224 is arranged on the side wall of the wax removal section 221 opposite to the S-shaped opening 225, that is, the wax removal groove 224 is arranged on the side of the wax removal section 221 where the first blade 2221 and the second blade 2231 are far apart, so that the size of the wax removal groove 224 can be increased as much as possible to improve the wax removal effect.

[0032] In this embodiment, the wax removal groove 224 is a trapezoidal groove, which effectively increases the outlet area of ​​the wax removal groove 224 compared to the arc groove in the prior art, further disperses the extrusion force on the scraping part 22, and avoids unidirectional deformation of the wax scraper 2 during operation.

[0033] In the above embodiment, the wax removal groove 224 and the S-shaped opening 225 are arranged relative to each other, so that the wax removal groove 224, the internal channel of the scraping part 22 and the S-shaped opening 225 are interconnected, so that when the first blade 2221 and the second blade 2231 are scraping wax, the wax scraps in the scraping part 22 can be discharged from the scraping part 22 through the wax removal groove 224 and the S-shaped opening 225, effectively preventing the wax scraps from accumulating and clogging the internal channel of the scraping part 22, so that the wax scraping sheet 2 can always move smoothly, thereby improving the wax scraping effect.

[0034] like Figure 1As shown, the wax scraping blade 2 also includes a connecting sleeve 21 respectively arranged on the first scraping segment 222 and the second scraping segment 223. The connecting sleeve 21 allows a certain distance between the scraping portion 22 and the center rod 1; the connecting sleeve 21 is movably arranged on the center rod 1 relative to the center rod 1, that is, the scraping portion 22 can move to a certain extent on the center rod 1 through the connecting sleeve 21. In this embodiment, it specifically means that the scraping portion 22 can axially rotate or axially slide relative to the center rod 1. The scraping portion 22 is arranged on the outside of the center rod 1 through the connecting sleeve 21, so that under the traction force of the ground operation, the scraping portion 22 can rotate relative to the center rod 1, thereby performing the wax scraping operation, further improving the efficiency of the wax scraping operation.

[0035] It should be understood that after the connection sleeve 21 is connected to the scraping portion 22, Figure 2 As shown, in order not to affect the passage of oil and gas in the internal channel of the scraping part 22, a gap for the passage of oil and gas is preset between the connecting sleeve 21 and the scraping part 22 except for the connection between the two.

[0036] In this embodiment, after the wax scraper 2 is connected to the center rod 1, the center axis of the wax scraper 2 coincides with the center axis of the center rod 1, achieving full-diameter scraping and ensuring the stability of the wax scraper 2 during the wax scraping operation.

[0037] As another embodiment, after the wax scraper is connected to the center rod, the center axis of the wax scraper does not coincide with the center axis of the center rod; specifically, the axis of the center rod is located on the side where the center axis of the wax scraper is away from the S-shaped opening, that is, the wax scraper is offset relative to the center rod; at this time, the first blade and the second blade are located at the tip of the center rod away from the S-shaped opening to form a primary scraping structure, and the first blade and the second blade are located near the S-shaped opening to form a secondary scraping structure, wherein the secondary scraping structure has the function of expanding the diameter and scraping. When applied, the primary scraping structure is first used to scrape the thicker wax deposited part of the pipe column, and then the secondary scraping structure is used to expand the diameter and scrape the wax deposited part, and graded scraping is achieved through the cooperation of the primary scraping structure and the secondary scraping structure.

[0038] like Figure 1 As shown, in this embodiment, the connecting sleeve 21 is fixed to the inner walls of the first blade portion 2221 and the second blade portion 2231 by welding, thereby ensuring reliable connection between the connecting sleeve 21 and the wax scraping blade 2 .

[0039] In this embodiment, a limiting portion 13 for limiting the axial movement of the scraping portion 22 is fixedly provided on the center rod 1, and the limiting portion 13 is provided between the two connecting sleeves 21; specifically, the limiting portion 13 is an annular protrusion convexly provided in the middle of the center rod 1. After the wax scraping blade 2 is connected to the center rod 1, the annular protrusion is located between the two connecting sleeves 21, so that the axial movement range of the scraping portion 22 along the center rod 1 can be limited, thereby ensuring the reliability and wax scraping effect of the wax scraping blade 2.

[0040] In other embodiments, the limiting part and the center rod can be separately provided. Specifically, the limiting part is a cylindrical hollow structure, and the limiting part and the center rod are fixedly connected by welding; or, two limiting parts are provided, which are respectively provided between the connecting sleeves or at appropriate positions outside the two connecting sleeves. It should be understood that the number and setting position of the limiting part 13 and the connection structure of the limiting part 13 and the center rod 1 can be reasonably selected and set according to actual needs, and this embodiment does not limit this.

[0041] In order to facilitate the connection between the center rod 1 and the wire rope and the weight rod 4, in this embodiment, the upper joint 11 and the lower joint 12 are respectively threadedly connected at both ends of the center rod 1, wherein the upper joint 11 is used to connect with the wire rope cap 3 and is connected to the wire rope through the wire rope cap 3. Specifically, the two ends of the center rod 1 are respectively provided with external threads, and the ends of the upper joint 11 and the lower joint 12 that cooperate with the center rod 1 are set as internal threads. In this way, the threaded connection structure is convenient for disassembly and assembly, and the connection is reliable; at the same time, the wire rope is connected through the wire rope cap 3, which reduces the probability of the wire rope being entangled, broken and stuck. Of course, in other embodiments, the opposite ends of the center rod 1 can be set as internal threads, and correspondingly, the ends of the upper joint 11 and the lower joint 12 that cooperate with the center rod 1 are set as external threads; in order to further ensure the reliability of the threaded connection between the center rod 1 and the wire rope cap 3 and the weight rod 4, it can be enhanced by welding after the threaded connection; or, the center rod 1 and the wire rope cap 3 and the weight rod 4 can be directly fixedly connected by welding.

[0042] It should be understood that when the pipe column needs to be dewaxed, wax scraping blades 2 with different outer diameters can be selected according to specific circumstances to meet different pipe column usage requirements.

[0043] When the wax cleaning tool provided by the utility model is used, the traction wire rope is connected through the wire rope cap 3, and the wax cleaning tool is lowered into the production pipe string to perform wax cleaning operations; the wax cleaning tool drives the traction wire rope to move downward under the action of its own gravity, and scrapes the accumulated wax on the inner wall of the production pipe string through the second blade 2231 located at the bottom; when the wax cleaning tool is lifted, the first blade 2221 located at the top scrapes the accumulated wax on the inner wall of the production pipe string. The wax cleaning tool reciprocates in the production pipe string, so that the accumulated wax on the inner wall of the production pipe string falls off under the action of the wax cleaning tool, thereby realizing the wax removal operation in the production pipe string.

[0044] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. The patent protection scope of the present invention shall be based on the claims. All equivalent structural changes made using the description and drawings of the present invention shall be included in the protection scope of the present invention.

Claims

1. A wax removal tool, comprising a central rod and a wax scraper sleeved on the outside of the central rod, the wax scraper comprising a wax removal section and a first scraping section and a second scraping section connected to opposite ends of the wax removal section, the wax removal section is provided with a wax removal structure, the wax removal structure comprising a wax removal groove, characterized in that: The wax discharge structure further comprises an S-shaped opening which is longitudinally penetrated and arranged on the wax discharge section relative to the wax discharge groove and is used for generating torque.

2. The wax removal tool according to claim 1, characterized in that: An angle is formed between the tangent direction of the S-shaped opening and the axial direction of the central rod.

3. The wax removal tool according to claim 1 or 2, characterized in that: The wax scraper is a cylindrical through-diameter structure, and the central axis of the central rod is located on the side of the central axis of the wax scraper away from the S-shaped opening.

4. The wax removal tool according to claim 1 or 2, characterized in that: The wax discharge groove is a trapezoidal groove.

5. The wax removal tool according to claim 1 or 2, characterized in that: The first scraping segment is provided with a first blade portion, and the second scraping segment is provided with a second blade portion. The first blade portion and the second blade portion both form an angle with the axial direction of the center rod, and the inclination direction of the first blade portion relative to the center rod is opposite to the inclination direction of the second blade portion relative to the center rod.

6. The wax removal tool according to claim 5, characterized in that: The first scraping segment and the second scraping segment are respectively provided with connecting sleeves rotatably connected to the central rod.

7. The wax removal tool according to claim 6, characterized in that: The center rod is provided with a limiting portion for limiting the axial movement of the wax scraping blade.

8. The wax removal tool according to claim 7, characterized in that: The limiting portion is arranged between the two connecting sleeves.

9. The wax removal tool according to claim 7, characterized in that: The limiting portion is an annular protrusion convexly arranged on the central rod.

10. The wax removal tool according to claim 1 or 2, characterized in that: The opposite ends of the central rod are respectively connected with an upper joint for connecting with a wire rope cap and a lower joint for connecting with a weighting rod through threads.

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