Wax scraping sampling tool and use method

Abstract

The invention provides a paraffin scraping and sampling tool and a use method, the paraffin scraping and sampling tool at least comprises two groups of coaxially arranged scrapers, and at least one group of sample collecting tubes is arranged between the scrapers; each of the two groups of scrapers comprises a prismatic table and a plurality of groups of arc-shaped blades uniformly distributed at the large end of the prismatic table, the arc-shaped blades are arranged along the axial direction of the sample collection tube, and the arc-shaped blades on the adjacent scrapers are arranged in a staggered manner; the scrapers are coaxially arranged, the arc-shaped blades are arranged in a staggered mode, wax sediments in different areas of the inner wall of the oil pipe can be longitudinally removed and sampled, the structure is simple, operation is convenient, the wax sediments can be effectively removed, and drill jacking and jamming accidents caused by the wax sediments are prevented.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil well dynamic monitoring, and particularly relates to a wax scraping and sampling tool and a using method thereof. Background Art

[0002] Paraffin is a component of crude oil, consisting of normal, isomeric or cycloalkanes, usually having a carbon chain of C20 and C100 or even higher. There are two processes for wax deposition in oil wells. First, wax precipitates from the crude oil, then aggregates and adheres to the pipe wall. The wax dissolved in the crude oil is condensed during the exploitation process because the dissolution ability of the crude oil for wax decreases. When the components, temperature, and pressure of the crude oil change and its dissolution ability decreases, a part of the wax is precipitated from the crude oil. Moreover, wax deposition in oil wells not only causes a large amount of daily management wax cleaning and workover wax cleaning workload, but also has a serious impact on oil well production and even oilfield development. Wax deposition in oil wells brings a large amount of work to daily management, increases the possibility and probability of downhole accidents, increases the oil flow resistance, reduces the oil well productivity, and the current wax cleaning measures will increase the development cost and affect the economic effect of oilfield development.

[0003] Currently, for the problem of wax deposition in oil production wells, devices such as wax scraping barrels or wax scraping blades are generally used to carry out wax cleaning operations. Because of their low cost and simple operation, they are widely popular. However, for wells with serious wax deposition, the wax scraping barrel is easy to be blocked, easy to cause drill sticking, and difficult to carry samples. The wax scraping blade also has problems such as easy sticking, easy falling objects, and no sample carrying. As a result, for some wells, wax cleaning requires manual pressing of steel wires, which is likely to cause secondary accidents such as drill sticking and pipe sticking, and the efficiency is not high. It is also impossible to analyze the physical property changes by analyzing wax samples and other foreign substances to find prevention and control means. Therefore, how to improve the wax cleaning efficiency, reduce sticking and drill sticking accidents, and at the same time obtain wax samples, asphaltenes and other foreign substances is worthy of research. Summary of the Invention

[0004] Aiming at the problems existing in the prior art, the present invention provides a wax scraping and sampling tool and a using method thereof, which can efficiently, quickly and low-cost remove the wax precipitate in the oil pipe and can collect wax samples for research and analysis.

[0005] The present invention is realized through the following technical solutions:

[0006] A wax scraping and sampling tool at least includes two groups of coaxially arranged scrapers, and at least one group of sample collection tubes is arranged between the scrapers;

[0007] Both of the two groups of scrapers include a frustum and multiple groups of arc-shaped blades evenly distributed at the large end of the frustum. The arc-shaped blades are arranged along the axial direction of the sample collection tube, and the arc-shaped blades on adjacent scrapers are arranged in a staggered manner.

[0008] Further, the sample collection tube is coaxially arranged with the scraper.

[0009] Further, the sample collection tube is of a hollow structure, and a sample inlet hole is provided on the side wall at the top end. The middle section penetrates through the frustum of the scraper connected thereto, and a sample overflow hole is provided at the bottom end.

[0010] Further, the blade body of the arc-shaped blade is a vertical arc-shaped sheet structure, and the tip of the arc-shaped blade is a circular arc-shaped structure.

[0011] Further, a chamfer is provided on the inner side of the tip of the arc-shaped blade.

[0012] . The wax scraping and sampling tool according to the claim, wherein adjacent arc-shaped blades located on the same frustum are connected by a connecting rod.

[0013] Further, the axial projections of the arc-shaped blades of the coaxially arranged scrapers do not overlap.

[0014] Further, the positions of the arc-shaped blades on different scrapers from the axis are not equal.

[0015] Further, there are at least two groups of arc-shaped blades on the same scraper.

[0016] A method for using a wax scraping and sampling tool, comprising the following steps:

[0017] Press the tip of the arc-shaped blade of the scraper against the inner wall of the oil pipe to be measured and push it along the axis of the oil pipe;

[0018] During the process of pushing the scraper, the arc-shaped blade drops the wax precipitate on the inner wall of the oil pipe from the pipe wall and continuously converges it into the sample collection tube;

[0019] During the process of pushing the scraper, the two scrapers respectively collect the wax precipitates on the inner walls of different regions of the oil pipe. After reaching the preset position, the wax scraping and sampling are completed.

[0020] Compared with the prior art, the present invention has the following beneficial technical effects:

[0021] The present invention provides a wax scraping and sampling tool, which at least includes two groups of coaxially arranged scrapers, and at least one group of sample collection tubes is arranged between the scrapers; the two groups of scrapers both include a frustum and multiple groups of arc-shaped blades evenly distributed at the large end of the frustum. The arc-shaped blades are arranged along the axial direction of the sample collection tube, and the arc-shaped blades on adjacent scrapers are all arranged in a staggered manner; in this application, the coaxially arranged scrapers and the arc-shaped blades arranged in a staggered manner can longitudinally remove and sample the wax precipitates in different regions of the inner wall of the oil pipe. The structure is simple, the operation is convenient, and the wax precipitate can be effectively removed, preventing the top drilling and sticking accidents caused by the wax precipitate.

[0022] The invention provides a method for using a wax scraping sampling tool, comprising the following steps: placing the tip of an arc-shaped blade of a scraper against the inner wall of an oil pipe to be measured and advancing along the axis of the oil pipe; in the process of advancing the scraper, the arc-shaped blade causes wax deposits located on the inner wall of the oil pipe to fall off the pipe wall and continuously flow into a sample collection tube; in the process of advancing the scraper, two groups of scrapers respectively collect wax deposits on the inner wall of the oil pipe in different areas, and after reaching a preset position, the wax scraping sampling is completed; the method is easy to operate and can quickly and efficiently remove wax deposits. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 This is a schematic diagram of the structure of a wax scraping sampling tool in an embodiment of the present invention;

[0024] Figure 2 is a side view of a scraper in an embodiment of the present invention;

[0025] Figure 3 A top view of a scraper having two arc-shaped blades according to an embodiment of the present invention;

[0026] Figure 4 is a top view of a scraper having three arc-shaped blades according to an embodiment of the present invention;

[0027] Figure 5 It is a schematic diagram of the combination of multiple scrapers in an embodiment of the present invention;

[0028] Figure 6 Schematic diagram of a combination of fewer scrapers in an embodiment of the present invention.

[0029] In the figure: 1. scraper; 2. sample collection tube; 3. sample inlet hole; 4. sample overflow hole; 5. connecting rod; 10. prism; 11. curved blade. DETAILED DESCRIPTION

[0030] The present invention is further described in detail below in conjunction with specific embodiments, which are intended to explain the present invention rather than to limit it.

[0031] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0032] It should be noted that the terms "first", "second", etc. in the description, claims and the above drawings of the present invention are used to distinguish similar objects, and do not necessarily have to be used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged under appropriate circumstances, so that the embodiments of the present invention described here can be implemented in an order other than those illustrated or described here. In addition, the terms "comprising" and "having" and any variations thereof are intended to cover non-exclusive inclusion. For example, a process, method, system, product or device comprising a series of steps or units does not have to be limited to those steps or units clearly listed, but may include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0033] An embodiment of the present invention provides a wax scraping and sampling tool, as Figure 1 shown, at least including two groups of scrapers 1 arranged coaxially, and at least one group of sample collection tubes 2 are arranged between the scrapers 1;

[0034] Both of the two groups of scrapers 1 include a frustum 10 and multiple groups of arc-shaped blades 11 evenly distributed at the large end of the frustum 10. The arc-shaped blades 11 are arranged along the axial direction of the sample collection tube 2, and the arc-shaped blades 11 on adjacent scrapers 1 are all arranged in a staggered manner.

[0035] It should be noted that, in this embodiment, there are two groups of the scrapers 1. If there are multiple groups of the scrapers 1, on the premise of ensuring that at least one group of sample collection tubes 2 are arranged between adjacent scrapers 1, the remaining adjacent scrapers 1 can be connected by arranging a shaft rod, and the shaft rod can be detachably connected by means of threads.

[0036] Preferably, the sample collection tube 2 is arranged coaxially with the scraper 1. It should be noted that, in this embodiment, the coaxially arranged sample collection tube 2 and the scraper 1 can make the arc-shaped blades 11 receive uniform force during the pushing process, and can be pushed evenly and stably. When the number of scrapers 1 is large, the stability of the pushing process is still ensured.

[0037] Preferably, the sample collection tube 2 is of a hollow structure, and a sample inlet hole 3 is provided on the side wall of the top end, the middle section penetrates through the frustum 10 of the scraper 1 connected thereto, and a sample overflow hole 4 is provided at the bottom. It should be noted that, in this embodiment, when the arc-shaped blades 11 are pushed forward, the wax precipitates scraped off will be continuously converged. The wax precipitates will accumulate and squeeze into the sample inlet hole 3. At the same time, as the pushing continues, the wax precipitates will reach the sample overflow hole 4 and overflow. Those skilled in the art can preset the length of the middle section of the sample collection tube 2, and thus can specifically collect and study the wax precipitates in the target area of the oil pipe.

[0038] Preferably, as Figure 3As shown, the blade body of the arc-shaped blade 11 is a vertical arc-shaped sheet structure, and the tip of the arc-shaped blade 11 is an arc-shaped structure. It should be noted that the vertical arc-shaped sheet structure of the blade body can advance along the inner wall of the oil pipe, thereby effectively removing wax precipitation. The arc-shaped tip structure can increase the local pressure during the advancement of the arc-shaped blade 11, thereby improving the advancement efficiency. Further, as Figure 4 shown, it is a top view of a scraper with three arc-shaped blades. Those skilled in the art can set the number of arc-shaped blades 11 according to actual production needs.

[0039] Preferably, a chamfer is provided inside the tip of the arc-shaped blade 11. It should be noted that the chamfer can increase the local pressure during the advancement of the arc-shaped blade 11 and at the same time facilitate the collection of the wax precipitation to be cleaned.

[0040] Preferably, adjacent arc-shaped blades 11 located on the same frustum 10 are connected by a connecting rod 5. It should be noted that the connecting rod 5 can improve the structural strength of adjacent arc-shaped blades 11, prevent damage to the scraper 1 by hard impurities in the wax precipitation, and at the same time, the connecting rod 5 can adapt to the process of high-speed advancement.

[0041] Preferably, the axial projections of the arc-shaped blades 11 of the coaxially arranged scrapers 1 do not overlap. It should be noted that non-overlapping projections can enable the arc-shaped blades 11 of different scrapers 1 to clean different areas inside the oil pipe.

[0042] Preferably, the positions of the arc-shaped blades 11 on different scrapers 1 from the axis are not equal. It should be noted that unequal positions from the axis can be applicable to oil pipes with different inner diameters or variable-diameter oil pipes. The variable-diameter oil pipe refers to an oil pipe with a continuously decreasing inner diameter. Those skilled in the art can preset multiple sets of scrapers 1 with different diameters according to the lengths of various regions of the variable-diameter oil pipe and adaptively set the distance between adjacent scrapers 1, thereby realizing the removal of wax precipitation in the variable-diameter oil pipe.

[0043] Preferably, there are at least two sets of arc-shaped blades 11 on the same scraper 1.

[0044] Preferably, when cleaning the inner wall of a relatively short oil pipe, those skilled in the art can set a handheld part at the end of the coaxially arranged scraper 1, such as Figure 6 shown, it can be a structure such as a handle, and it can be removed manually or by machine propulsion; when cleaning the inner wall of a relatively long oil pipe, those skilled in the art can tow the wax scraping and sampling tool at one end of the oil pipe, and at the same time, multiple sets of scrapers 1 can be set on the wax scraping and sampling tool, such as Figure 5As shown, by increasing the length or inner diameter of the sample collection tube 2, the collection amount of wax precipitation is increased. At the same time, the misalignment angle of the arc-shaped blades 11 on the adjacent scrapers 1 adopts a small-angle misalignment method, or a segmented cleaning method is adopted to clean a longer oil pipe, etc.

[0045] Specifically, the scraper 1, the sample collection tube 2 and the shaft rod are all connected by a threaded connection, which is convenient for those skilled in the art to perform combined connection for different oil pipes.

[0046] Furthermore, when cleaning the inner wall of a longer oil pipe, those skilled in the art can set multiple groups of coaxially arranged scrapers 1 with diameters increasing step by step, that is, the inner diameter of the scraper 1 at the front end in the advancing direction is smaller, and the inner diameter of the scraper 1 at the end in the advancing direction is larger. Such a setting method can adopt a layer-by-layer cleaning method for the wax precipitation on the inner wall of the oil pipe, and can reduce the cleaning pressure of each scraper 1;

[0047] Still further, when the number of scrapers 1 is large, those skilled in the art can set a radial support frame on the axial connecting rod of the wax scraping and sampling tool to prevent the problem of circumferential line deviation of the scraper 1 with a smaller diameter during the process of cleaning wax precipitation.

[0048] The present invention provides a method for using a wax scraping and sampling tool, including the following steps:

[0049] Press the tip of the arc-shaped blade 11 of the scraper 1 against the inner wall of the oil pipe to be measured and advance along the axis of the oil pipe;

[0050] During the advancement of the scraper 1, the arc-shaped blade 11 drops the wax precipitation on the inner wall of the oil pipe from the pipe wall and continuously converges into the sample collection tube 2;

[0051] During the advancement of the scraper 1, the two groups of scrapers 1 respectively collect the wax precipitation on the inner wall of different areas of the oil pipe. After reaching the preset position, the wax scraping and sampling are completed.

[0052] For the wax scraping and sampling tool described in the present application, 154 well-times have been implemented after production. During the wax scraping period, the time and intensity of pressing the steel wire have been significantly reduced by 89%. No top drilling or sticking accidents have occurred. At the same time, the collected wax samples have all been collected, and the wax cleaning efficiency has been significantly improved, and the sampling effect is outstanding.

[0053] Finally, it should be noted that: the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that: it is still possible to modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements for some or all of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wax scraping and sampling tool, characterized in that, it includes at least two groups of scrapers (1) arranged coaxially, and at least one group of sample collection tubes (2) is arranged between the scrapers (1); Both groups of the scrapers (1) include frustums (10) and multiple groups of arc-shaped blades (11) evenly distributed at the large ends of the frustums (10). The arc-shaped blades (11) are arranged along the axial direction of the sample collection tube (2), and the arc-shaped blades (11) on adjacent scrapers (1) are arranged in a staggered manner.

2. The wax scraping and sampling tool according to claim 1, characterized in that, the sample collection tube (2) is arranged coaxially with the scraper (1).

3. The wax scraping and sampling tool according to claim 1, characterized in that, the sample collection tube (2) is of a hollow structure, and a sample inlet hole (3) is provided on the side wall of the top end. The middle section penetrates through the frustum (10) of the scraper (1) connected thereto, and a sample overflow hole (4) is provided at the bottom.

4. The wax scraping and sampling tool according to claim 1, characterized in that, the blade body of the arc-shaped blade (11) is a vertical arc-shaped sheet structure, and the tip of the arc-shaped blade (11) is a circular arc structure.

5. The wax scraping and sampling tool according to claim 1, characterized in that, a chamfer is provided on the inner side of the tip of the arc-shaped blade (11).

6. The wax scraping and sampling tool according to claim 1, characterized in that, adjacent arc-shaped blades (11) on the same frustum (10) are connected by a connecting rod (5).

7. The wax scraping and sampling tool according to claim 1, characterized in that, the projections of the arc-shaped blades (11) of the coaxially arranged scrapers (1) along the axial direction do not overlap.

8. The wax scraping and sampling tool according to claim 1, characterized in that, the positions of the arc-shaped blades (11) on different scrapers (1) from the axis are not equal.

9. The wax scraping and sampling tool according to claim 1, characterized in that, there are at least two groups of arc-shaped blades (11) on the same scraper (1).

10. A method for using a wax scraping and sampling tool, characterized in that, based on the wax scraping and sampling tool according to any one of claims 1-9, it includes the following steps: Press the tip of the arc-shaped blade (11) of the scraper (1) against the inner wall of the oil pipe to be measured and push it along the axis of the oil pipe; During the process of pushing the scraper (1), the arc-shaped blade (11) drops the wax precipitate on the inner wall of the oil pipe from the pipe wall and continuously converges into the sample collection tube (2); During the process of pushing the scraper (1), the two groups of scrapers (1) respectively collect the wax precipitates on the inner walls of different regions of the oil pipe. After reaching the preset position, the wax scraping and sampling is completed.

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