A strong erosion-resistant composite temporary plugging ball

Abstract

The present invention discloses a highly erosion-resistant composite temporary plugging ball, comprising a core and a metal fiber coating layer covering the core. Compared with ordinary temporary plugging balls, the present invention has higher erosion resistance and sealing ability. Rock debris or proppant particles are embedded in the gaps of the outer metal fiber coating layer to protect the inner core. Subsequent proppants will only grind the particles embedded in the gaps of the metal fiber coating layer. As the wear intensifies, the original particles are worn and new gaps are generated. New rock debris or proppant particles will be embedded in the new gaps, achieving continuous protection of the temporary plugging ball, thereby avoiding the influence of temporary plugging ball erosion on the temporary plugging effect. At the same time, the proppant will gradually gather at the gap and self-accumulate to improve the sealing effect. The present invention can effectively improve the flow limiting effect, mining efficiency, and make each cluster of cracks expand evenly and effectively. It can reduce the wear of the temporary plugging ball by the proppant when the temporary plugging ball is set to seal an irregular-shaped blasthole, thereby improving the efficiency of oil and gas production.

Description

Technical Field

[0001] The invention relates to the technical field of oil and gas field exploitation, and in particular to a highly erosion-resistant composite temporary plugging ball. Background Art

[0002] In the field of oil and gas field exploitation in my country, unconventional oil and gas reservoirs have gradually become the main development direction. However, unconventional oil and gas reservoirs have low porosity and low permeability, making them difficult to exploit. During the staged fracturing process, the perforation diversion has differences, resulting in uneven expansion of some cracks, which will affect the efficiency of oil and gas extraction.

[0003] Fracturing ball-dropping temporary plugging and diversion technology is widely used in oil and gas production from unconventional reservoirs such as shale gas and tight oil. This technology involves dropping temporary plugging balls into the well. The balls are then carried by the fluid to the perforations and set, redistributing the fluid toward the perforations that originally had low permeability, thereby achieving uniform fracture expansion and diversion.

[0004] However, the fracturing fluid will be throttled at the blasthole, and the proppant will flow at high speed, causing serious erosion at the blasthole, increasing the blasthole aperture to form irregular holes. Due to the irregularity of the holes, the common temporary plugging balls cannot completely block the holes after being set. The proppant will pass through at high speed and continue to grind the temporary plugging balls, causing material loss in the temporary plugging balls, making it difficult to redistribute the fluid to the holes of low permeability fractures. The undeveloped fractures are difficult to continue to expand, making it difficult to increase the production volume. Summary of the Invention

[0005] In view of the above problems, the present invention aims to provide a highly erosion-resistant composite temporary plugging ball.

[0006] The technical solutions of the present invention are as follows:

[0007] A highly erosion-resistant composite temporary plugging ball comprises a ball core and a metal fiber coating layer covering the ball core.

[0008] Preferably, the core is made of degradable material or non-degradable material.

[0009] Preferably, the core is a rigid core or an elastic core.

[0010] Preferably, the core is a hollow structure or a solid structure.

[0011] Preferably, the metal fiber coating layer is provided in multiple layers.

[0012] Preferably, the metal fiber coating layer is formed by interweaving metal fibers.

[0013] The beneficial effects of the present invention are:

[0014] 1. The temporary plugging ball structure of the present invention has high interchangeability, and the shape, material and structure of the ball core can be adjusted arbitrarily according to actual conditions.

[0015] 2. The temporary plugging ball of the present invention is composed of an outer metal fiber coating and an inner ball core. Rock debris or proppant particles will be embedded in the gaps of the outer metal fiber coating, making the temporary plugging ball have higher wear resistance.

[0016] 3. The temporary plugging ball of the present invention has a continuously updated wear-resistant protective layer. After rock chips or proppant particles are embedded in the gaps of the metal fiber coating layer of the temporary plugging ball, the subsequent proppant will only grind the particles originally embedded in the gaps of the metal fiber coating layer. As the wear intensifies, the original particles are worn away and new gaps are generated. New rock chips or proppant particles will be embedded in the gaps of the metal fiber coating layer of the temporary plugging ball to form a new wear-resistant layer.

[0017] 4. Due to the restrictive effect of the metal fiber coating, the proppant will gradually gather in the gaps and self-accumulate to improve the sealing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0019] Figure 1 This is a schematic structural diagram of the highly erosion-resistant composite temporary plugging ball of the present invention;

[0020] Figure 2 This is a schematic diagram of the structure of the strong erosion-resistant composite temporary plugging ball and the ordinary temporary plugging ball for sealing the hole;

[0021] Figure 3 This is a schematic diagram of the erosion state of ordinary temporary plugging balls;

[0022] Figure 4 This is a schematic diagram of the state in which the highly erosion-resistant composite temporary plugging ball of the present invention undergoes erosion and produces a self-accumulated protective layer of proppant;

[0023] Figure 5 Schematic diagram of the structure when the core is spherical and its shape is consistent with the shape of the outer metal fiber coating layer;

[0024] Figure 6 Schematic diagram of the structure when the core is non-spherical and its shape is consistent with the shape of the outer metal fiber coating layer;

[0025] Figure 7 This is a schematic diagram of the state of the highly erosion-resistant composite temporary plugging ball when rock cuttings and proppant particles are embedded in the present invention. DETAILED DESCRIPTION

[0026] The present invention is further described below with reference to the accompanying drawings and examples. It should be noted that, in the absence of conflict, the embodiments in this application and the technical features in the embodiments can be combined with each other. It should be noted that, unless otherwise specified, all technical and scientific terms used in this application have the same meanings as those commonly understood by those of ordinary skill in the art to which this application belongs. The use of similar words such as "include" or "comprising" in the present invention means that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects.

[0027] like Figure 1 As shown, the present invention provides a highly erosion-resistant composite temporary plugging ball, comprising a ball core and a metal fiber coating layer covering the ball core.

[0028] In the present invention, the core can be of any suitable material, structure and shape, and the outer metal fiber coating enables the present invention to meet the wear resistance required by the temporary plugging ball. The temporary plugging ball of the present invention has the property of continuously renewing the wear-resistant layer. Specifically, the temporary plugging ball protects the temporary plugging ball core through the rock chips or proppant particles embedded in the gaps of the outer metal fiber coating. The subsequent proppant will only grind the particles embedded in the gaps of the metal fiber coating. As the wear intensifies, the original particles are worn and new gaps are generated. New rock chips or proppant particles will be embedded in the gaps of the outer metal fiber coating of the temporary plugging ball to achieve the above-mentioned function of continuously renewing the wear-resistant layer, thereby improving the wear resistance of the temporary plugging ball and avoiding the impact of temporary plugging due to erosion of the temporary plugging ball. At the same time, due to the restrictive effect of the metal fiber coating, the proppant will gradually gather in the gaps and self-accumulate to improve the sealing effect.

[0029] In a specific embodiment, the core is made of a degradable material or a non-degradable material. Optionally, the degradable material includes polylactic acid (PLA), polyglycolic acid (PGA), polyvinyl alcohol (PVA), etc. The non-degradable material includes olefin thermoplastic elastomers TPO and TPV, insoluble metal materials, glass, rubber, etc.

[0030] In a specific embodiment, the core is a rigid core or an elastic core.

[0031] In a specific embodiment, the core is a hollow structure or a solid structure.

[0032] In a specific embodiment, the metal fiber coating layer is provided with multiple layers. It should be noted that the number of layers of the metal fiber coating layer can be any number, which can be determined according to the wear resistance requirements on site.

[0033] In a specific embodiment, the metal fiber coating layer is formed by interweaving metal fibers.

[0034] The state when the strong erosion-resistant composite temporary plugging ball of the present invention and the ordinary temporary plugging ball are used for setting is as follows: Figure 2 and Figure 3 As shown in the figure, since the microstructure of the hole is not theoretically circular, ordinary temporary plugging balls still have gaps after being set. The proppant will grind the temporary plugging balls through the gaps. Ordinary temporary plugging balls will wear quickly, causing the gaps to gradually expand and the plugging ability to decline rapidly.

[0035] The present invention uses a temporary plugging ball with a spherical core to block the hole, achieving a temporary plugging effect with strong erosion resistance. Figure 4 As shown, the highly erosion-resistant composite temporary plugging ball of the present invention has a continuously updated wear-resistant protective layer. After rock cuttings or proppant particles are embedded in the gaps of the metal fiber coating layer of the temporary plugging ball, the subsequent proppant will only grind the particles originally embedded in the gaps of the metal fiber coating layer. As the wear intensifies, the original particles are worn and new gaps are generated. New rock cuttings or proppant particles will be embedded in the gaps of the metal fiber coating layer of the temporary plugging ball to form a new wear-resistant layer. At the same time, due to the limiting effect of the metal fiber coating, the proppant will gradually gather at the gaps and self-accumulate to improve the sealing effect. Therefore, the highly erosion-resistant temporary plugging ball of the present invention avoids the influence of erosion of the temporary plugging ball on the temporary plugging effect, effectively improves the flow limiting effect, mining efficiency, and allows each cluster of cracks to expand evenly and effectively.

[0036] In a specific embodiment, the highly erosion-resistant composite temporary plugging ball structure of the present invention is as follows Figure 5 As shown, it is composed of an outer metal fiber layer covering a spherical core, and the shape of the inner core of the temporary blocking ball is consistent with the outer metal fiber covering layer.

[0037] In a specific embodiment, the highly erosion-resistant composite temporary plugging ball structure of the present invention is as follows Figure 6 As shown, it is composed of an outer metal fiber layer covering a special-shaped non-spherical core, and the shape of the inner core of the temporary blocking ball is consistent with the outer metal fiber covering layer.

[0038] In a specific embodiment, the state of the rock cuttings or proppant particles embedded in the gaps of the outer metal fiber coating layer of the strong erosion-resistant composite temporary plugging ball of the present invention is as follows: Figure 7 shown.

[0039] The above description is merely a representative embodiment of the present invention and does not constitute any form of limitation to the present invention. Any technical personnel familiar with the present invention who, without departing from the scope of the technical solution of the present invention, makes some changes or modifications to the embodiments disclosed above using the technical contents disclosed above are equivalent embodiments of the present invention. However, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A strong erosion-resistant composite temporary blocking ball, characterized in that: The invention comprises a spherical core and a metal fiber covering layer covering the spherical core. The metal fiber covering layer is formed by interweaving metal fibers. Rock fragments or proppant particles can be embedded in the gaps of the outer metal fiber covering layer.

2. The strong erosion-resistant composite temporary blocking ball according to claim 1 is characterized in that: The core is made of degradable material or non-degradable material.

3. The strong erosion-resistant composite temporary blocking ball according to claim 1 is characterized in that: The core is a rigid core or an elastic core.

4. The strong erosion-resistant composite temporary blocking ball according to claim 1 is characterized in that: The spherical core is a hollow structure or a solid structure.

5. The strong erosion-resistant composite temporary blocking ball according to claim 1 is characterized in that: The metal fiber covering layer is provided with multiple layers.

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