Room temperature curing high performance composite material and method for preparing centralizer using the same

Abstract

This invention relates to a high-performance composite material that cures at room temperature and a method for preparing a centralizer using the same. The composite material comprises component A and component B, with a mass ratio of component A to component B of 100:(1-16.5). Component A comprises the following components in parts by mass: 40-70 parts epoxy resin matrix; 0.01-0.5 parts coupling agent; 0.5-5 parts accelerator; 0.05-1 part dispersant; 30-60 parts filler; 0.5-2 parts defoamer; and 0.1-0.5 parts adhesion promoter. Component B is a curing agent. Through component compatibility and process optimization, this invention offers the following advantages: (1) customizable design to suit different working conditions; (2) significantly reduced friction during casing installation; (3) suitable for complex environments in conventional and small-diameter wells; (4) ensuring stable and continuous circulation of drilling fluid cement; and (5) excellent resistance to extreme wear and impact. This invention provides a high-performance, highly adaptable new solution for casing centralization in petroleum engineering.

Description

Technical Field

[0001] This invention relates to the field of petroleum engineering technology, and more specifically, to a high-performance composite material that cures at room temperature and a method for preparing a centralizer using the same. Background Technology

[0002] In oil drilling engineering, the casing centralizer is the core tool for ensuring cementing quality. Its core function is to ensure that the casing remains centered during the running process, thereby optimizing the drilling fluid flow characteristics, improving the uniformity of the cement sheath, and ultimately ensuring the integrity and long-term sealing of the wellbore. As global oil and gas development expands to complex conditions such as ultra-deep wells, highly deviated wells, small wellbores, and high temperature and pressure, the technical bottlenecks of traditional centralizers are becoming increasingly prominent. At present, unconventional oil and gas resource development is advancing in depth towards deep, ultra-deep and shale gas horizontal wells, and existing technologies face multiple challenges: (1) Traditional metal centralizers are prone to pitting and perforation in H2S / CO2 corrosive media; (2) When operating in small wellbores, the insufficient outer diameter margin of conventional centralizers leads to poor casing centering, which seriously affects the cement sheath sealing quality; (3) When running casing in horizontal well sections, the running friction is too high, which can easily cause casing buckling, stuck pipe, and other problems in horizontal well sections, which greatly hinders the smooth progress of the operation.

[0003] Although composite materials have shown great potential for application in the petroleum engineering field due to their advantages such as lightweight and corrosion resistance, their engineering applications are limited by complex preparation processes and harsh curing conditions. For example, Chinese patent document CN102775788A discloses a high-temperature resistant coating composite material and its preparation method, which obtains a high-strength structure through high-temperature compression molding (360℃ / 15MPa), but the harsh curing conditions prevent in-situ molding at the well site, limiting its adaptability to complex well conditions. Similarly, Chinese patent document CN110305476A discloses a polyamide centralizer composite material and its preparation method, which has high specific strength characteristics, but requires material to be fed through a twin-screw extruder and then subjected to high-temperature injection molding, and the complex molding process also restricts its widespread application. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a high-performance composite material that cures at room temperature and a method for preparing a centralizer using the composite material, which can achieve room temperature bonding and integral molding with the casing surface without the need for additional mechanical fixing structures; the centralizer has a low coefficient of friction, high wear resistance and excellent impact resistance, and can be adapted to complex working conditions such as ultra-deep wells, small wellbores and highly deviated wells.

[0005] The technical solution adopted by the present invention to solve its technical problem is: to construct a high-performance composite material that cures at room temperature, comprising component A and component B, wherein the mass ratio of component A to component B is 100:(1-16.5). Component A comprises the following components in parts by mass: 40-70 parts epoxy resin matrix; 0.01-0.5 parts of coupling agent; Accelerator 0.5-5 parts; Dispersant 0.05-1 part; 30-60 parts of filler; Defoamer 0.5-2 parts; Adhesion promoter 0.1-0.5 parts; Component B is a curing agent.

[0006] According to the above scheme, the epoxy resin matrix is ​​one or more combinations of bisphenol A type epoxy resin, bisphenol F type epoxy resin, or hydrogenated bisphenol A type epoxy resin.

[0007] According to the above scheme, the coupling agent is one or more combinations of silane coupling agents, titanate coupling agents or aluminate coupling agents, preferably at least one of γ-aminopropyltriethoxysilane and isopropyltrioleoyloxytitanate.

[0008] According to the above scheme, the accelerator is one or more combinations of amine accelerators, imidazole accelerators or tertiary amine accelerators, preferably at least one of dimethylbenzylamine, 2-ethyl-4-methylimidazole and triethanolamine.

[0009] According to the above scheme, the dispersant is one or more of nonionic dispersants, anionic dispersants, or polymeric dispersants, preferably at least one of polyvinylpyrrolidone, polycarboxylate, and ammonium polyacrylate.

[0010] According to the above scheme, the packing material comprises the following components, by mass percentage: Carbon fiber: 0.1%-0.5%, activated carbon powder: 0.05%-0.1%, nano titanium dioxide: 0.5%-1%, silicon powder: 10%-14%, zirconium oxide: 16%-20%, boron carbide (B4C): 13%-17%, silicon nitride: 13%-17%, talc: 23%-27%, wollastonite: 12%-16%.

[0011] According to the above scheme, the defoamer is one or more of the following: silicone defoamer, polyether defoamer, or mineral oil defoamer, preferably at least one of polydimethylsiloxane or polyether-modified siloxane.

[0012] According to the above scheme, the adhesion promoter is one or more combinations of epoxy silanes, phosphate esters, and titanates, preferably at least one of γ-glycidoxypropyltrimethoxysilane, triphenyl phosphate, and isopropyltris(dioctylpyrophosphate)titanate.

[0013] According to the above scheme, the curing agent of component B is one or more of aliphatic amine curing agents, aromatic amine curing agents, or polyamide curing agents, preferably at least one of diethylenetriamine, m-phenylenediamine, and polyamide 651.

[0014] The present invention also provides a method for preparing a centralizer using the aforementioned room-temperature curing high-performance composite material, comprising the following steps: (1) First, add the weighed coupling agent, accelerator, dispersant and adhesion promoter to the epoxy resin matrix in sequence. During the addition process, turn on the stirring equipment and stir at a low speed (100-300r / min) to initially disperse each additive in the epoxy resin matrix. The stirring time is 5-10min to ensure that there is no obvious agglomeration.

[0015] (2) For fillers, first mix the difficult-to-disperse fillers such as carbon fiber, activated carbon powder, and nano titanium dioxide with the epoxy resin matrix, and use high-speed stirring (500-1000 r / min) or ultrasonic dispersion to prepare a pre-dispersion, so that the carbon fiber and activated carbon powder are evenly dispersed and avoid entanglement or agglomeration. Then, add the remaining fillers to the above mixture in proportion, gradually increase the stirring speed to 300-500 r / min, and continue stirring for 20-30 min to make the fillers and resin matrix fully mixed, ensuring that the fillers are evenly dispersed in the resin without obvious precipitation or agglomeration.

[0016] (3) Add the weighed defoamer to the mixed system and stir at medium speed (200-400r / min) for 5-10 minutes to eliminate the bubbles generated during the mixing process and make the A component system more uniform and stable.

[0017] (4) Sandblast the target location of the sleeve to be installed with the centralizer until the surface roughness reaches Ra>6μm.

[0018] (5) Fix the custom mold onto the surface of the sandblasted sleeve to ensure that the mold fits tightly against the sleeve.

[0019] (6) Mix the A component obtained in step (1)-(3) with the curing agent B component according to the mass ratio of A component to B component 100:14. Stir mechanically at a speed of 200-300r / min for 2-5min until the system color is uniform.

[0020] (7) Quickly inject the well-mixed composite material into the fixed mold, and maintain a uniform injection speed to avoid air bubbles being trapped.

[0021] (8) Allow the composite material in the mold to cure naturally at room temperature. Depending on the actual situation, the curing time is usually 5-30 hours. After the composite material is completely cross-linked and cured, remove the mold to obtain the target centralizer product.

[0022] The room-temperature curing high-performance composite material and the method for preparing a centralizer using the present invention have the following beneficial effects: 1. This invention utilizes the porous structure of activated carbon powder to adsorb well fluid and form a solid lubricating film, the graphitized layer of which provides a low-friction surface; the interlayer slip effect of talc powder and the hardness of boron carbide work together to form a "lubrication-support" dual-function interface, which further reduces the friction between the centralizer and the well wall, allowing the casing to be run into the well more smoothly and reducing resistance and energy consumption during the running process.

[0023] 2. This invention utilizes the high modulus properties of carbon fiber to construct a high-strength skeleton support structure, and combines this with the reinforcing effect of nano-titanium oxide at the matrix interface to form a synergistic reinforcement mechanism, significantly improving the deformation resistance and structural rigidity of the centralizer matrix material. This ensures the casing's centering within the wellbore, constructs a regular and stable annular flow channel, guarantees the smooth and continuous circulation of drilling fluid and cementing cement, and greatly improves the quality of cement annular sealing.

[0024] 3. The hard particles such as carbon fiber, zirconium oxide, and boron carbide, as well as the reinforcing phases such as nano-titanium oxide in the filler of this invention, significantly improve the hardness, wear resistance, and impact resistance of the composite material, enabling it to withstand wear and impact under extreme conditions and extend the service life of the centralizer.

[0025] 4. By adjusting the shape and size of the mold, this invention can produce a suitable centralizer according to different working conditions, meeting the usage requirements in complex environments such as ultra-deep wells, small wellbores, and highly deviated wells.

[0026] 5. The room temperature curing process of this invention does not require harsh high temperature and high pressure conditions, and can be formed in situ at the well site. It is suitable for complex environments of conventional and small wellbores, improving the convenience and flexibility of operation. Detailed Implementation

[0027] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the present invention will be further described in detail below with reference to specific embodiments. The technical solutions in the embodiments of this application will be clearly and completely described. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0028] Example 1 (1) Preparation of component A: Weigh 60 parts of bisphenol A type epoxy resin as the epoxy resin matrix, add 0.2 parts of γ-aminopropyltriethoxysilane as a coupling agent, 2 parts of dimethylbenzylamine as an accelerator, 0.5 parts of polyvinylpyrrolidone as a dispersant, and 0.3 parts of γ-glycidoxypropyltrimethoxysilane as an adhesion promoter, and add them sequentially to a stirring container. Stir at a low speed of 200 r / min for 8 min to initially disperse the additives in the epoxy resin matrix without obvious agglomeration.

[0029] Weigh out 40 parts of filler consisting of 0.3% carbon fiber, 0.08% activated carbon powder, 0.8% nano titanium dioxide, 12% silicon powder, 18% zirconium oxide, 15% boron carbide (B4C), 15% silicon nitride, 25% talc powder, and 14% wollastonite (all by mass percentage). First, mix the carbon fiber, activated carbon powder, nano titanium dioxide, and part of the epoxy resin matrix and prepare a pre-dispersion by high-speed stirring (800 r / min). Then, add the remaining filler to the mixture and gradually increase the stirring speed to 400 r / min. Continue stirring for 25 min to ensure that the filler and resin matrix are fully mixed without obvious precipitation or agglomeration.

[0030] Add 1 part of polydimethylsiloxane as an antifoaming agent, and stir at a medium speed of 300 r / min for 8 min to eliminate the bubbles generated during the mixing process, thus obtaining component A.

[0031] (2) Sleeve treatment and mold fixing The target location on the sleeve to be installed with the centralizer is sandblasted until the surface roughness Ra>6μm. A custom mold is then fixed onto the sandblasted sleeve surface, ensuring a tight fit between the mold and the sleeve.

[0032] (3) Weigh 100 parts of component A and 2.4 parts of component B (using diethylenetriamine as the curing agent). Add component B to component A and stir mechanically at 250 r / min for 2-5 min until the system is uniform in color. Quickly pour the uniformly mixed composite material into the fixed mold and allow it to cure at room temperature.

[0033] (4) Allow the composite material in the mold to cure naturally for 20 hours at room temperature (12℃). After complete cross-linking and curing, remove the mold to obtain the stabilizer product.

[0034] Example 2 (1) Preparation of component A Weigh 50 parts of bisphenol F type epoxy resin and 20 parts of hydrogenated bisphenol A type epoxy resin as epoxy resin matrix. Add 0.3 parts of isopropyl trioleoyl oxytitanate as coupling agent, 3 parts of 2-ethyl-4-methylimidazolium as accelerator, 0.8 parts of polycarboxylate as dispersant, and 0.4 parts of triphenyl phosphate as adhesion promoter. Add these to a stirring container in sequence and stir at a low speed of 150 r / min for 10 min to initially disperse the additives in the epoxy resin matrix.

[0035] Weigh out 50 parts of filler consisting of 0.4% carbon fiber, 0.1% activated carbon powder, 1% nano titanium dioxide, 14% silicon powder, 20% zirconium oxide, 17% boron carbide (B4C), 17% silicon nitride, 27% talc powder, and 16% wollastonite (all by mass percentage). First, mix the carbon fiber, activated carbon powder, and nano titanium dioxide with a portion of the epoxy resin matrix and prepare a pre-dispersion by ultrasonic dispersion. Then, add the remaining filler to the mixing system and gradually increase the stirring speed to 500 r / min. Continue stirring for 20 min to ensure that the filler and resin matrix are fully mixed.

[0036] Add 1.5 parts of polyether-modified siloxane as a defoamer, stir at a medium speed of 400 r / min for 5 min to eliminate bubbles, and obtain component A.

[0037] (2) The sleeve treatment and mold fixing are the same as in Example 1.

[0038] (3) Weigh 100 parts of component A and 15 parts of component B (m-phenylenediamine is selected as the curing agent), mix and stir evenly, and then inject into the mold. The operation is the same as in Example 1.

[0039] (4) Curing at room temperature (3℃) for 24 hours, removing the mold, and obtaining the centralizer product.

[0040] Example 3 (1) Preparation of component A Weigh 40 parts of bisphenol A type epoxy resin as epoxy resin matrix, add 0.05 parts of silane coupling agent (γ-aminopropyltriethoxysilane and isopropyltrioleoyloxytitanate mixed in a 1:1 ratio), 0.5 parts of triethanolamine as accelerator, 0.05 parts of ammonium polyacrylate as dispersant, and 0.1 parts of isopropyltris(dioctylpyrophosphate)titanate as adhesion promoter, and add them sequentially to a stirring container. Stir at a low speed of 300 r / min for 5 min to initially disperse the additives.

[0041] Weigh out 60 parts of a filler consisting of 0.1% carbon fiber, 0.05% activated carbon powder, 0.5% nano titanium dioxide, 10% silicon powder, 16% zirconium oxide, 13% boron carbide (B4C), 13% silicon nitride, 23% talc powder, and 12% wollastonite (all by mass percentage). First, pre-disperse the difficult-to-disperse filler, and then mix it with the remaining filler. Stir at 300 r / min for 30 min.

[0042] Add 0.5 parts of organosilicon defoamer (polydimethylsiloxane and polyether-modified siloxane mixed in a 1:1 ratio), and stir at a medium speed of 200 r / min for 10 min to obtain component A.

[0043] (2) The sleeve treatment and mold fixing are the same as in Example 1.

[0044] (3) Weigh 100 parts of component A and 6.8 parts of component B (curing agent is polyamide 651), mix and stir evenly, then inject into the mold, and operate as in Example 1.

[0045] (4) Curing at room temperature (23℃) for 16 hours, removing the mold, and obtaining the centralizer product.

[0046] Comparative Example 1 Referring to the materials and manufacturing methods of commercially available resin composite centralizers, commercially available nylon 66 resin was selected as the matrix material. Approximately 10% (by mass) of 10mm short-cut glass fibers and 3% (by mass) of nano-AlO3 were added as reinforcing phases. The appropriate masses of PA66, nano-Al2O3, and glass fibers were weighed using an electronic balance and placed into a high-speed mixer. Mixing for 45-90 seconds yielded a well-mixed PA66 / GF / Nano-Al2O3 compound. This compound was melt-blended and granulated using a twin-screw extruder at 260℃, and then injection molded at 250℃ and 100MPa to obtain the nylon-based composite material.

[0047] Comparative Example 2 Using commercially available nylon 66 resin as the matrix, approximately 10% (by mass) of 10mm short-cut glass fibers and approximately 9% (by mass) of 20mm short-cut carbon fibers were added for reinforcement. The appropriate masses of PA66, carbon fibers, and glass fibers were weighed using an electronic balance and placed into a high-speed mixer. Mixing for 45-90 seconds yielded a well-mixed PA66 / GF / CF compound. This compound was then melt-blended and granulated using a twin-screw extruder at 260℃, followed by injection molding at 250℃ and an injection pressure of 100MPa to obtain a nylon-based composite material.

[0048] The test data for Examples 1-3 and Comparative Examples 1-2 are shown in Table 1.

[0049] Table 1 Test Data

[0050] As can be seen from the test data, the centralizer prepared by this invention is significantly superior to traditional nylon-based composite materials in key properties such as compressive strength, hardness, and wear resistance. It is especially suitable for complex working conditions such as ultra-deep wells and small wellbores, providing a high-performance solution for casing centralization in petroleum engineering.

[0051] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A high-performance composite material that cures at room temperature, characterized in that, It includes component A and component B, wherein the mass ratio of component A to component B is 100:(1-16.5). Component A comprises the following components in parts by mass: 40-70 parts epoxy resin matrix; 0.01-0.5 parts of coupling agent; Accelerator 0.5-5 parts; Dispersant 0.05-1 part; 30-60 parts of filler; 0.5-2 parts of defoamer; Adhesion promoter 0.1-0.5 parts; Component B is a curing agent.

2. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The epoxy resin matrix is ​​one or more combinations of bisphenol A type epoxy resin, bisphenol F type epoxy resin, or hydrogenated bisphenol A type epoxy resin.

3. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The epoxy resin matrix is ​​one or more combinations of bisphenol A type epoxy resin, bisphenol F type epoxy resin, or hydrogenated bisphenol A type epoxy resin.

4. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The accelerator is one or more combinations of amine accelerators, imidazole accelerators, or tertiary amine accelerators.

5. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The dispersant is one or more of the following: nonionic dispersant, anionic dispersant, or polymeric dispersant.

6. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The filler comprises the following components, by mass percentage: Carbon fiber: 0.1%-0.5%, activated carbon powder: 0.05%-0.1%, nano titanium dioxide: 0.5%-1%, silicon powder: 10%-14%, zirconium oxide: 16%-20%, boron carbide (B4C): 13%-17%, silicon nitride: 13%-17%, talc: 23%-27%, wollastonite: 12%-16%.

7. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The defoamer is one or more of the following: silicone defoamer, polyether defoamer, or mineral oil defoamer.

8. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The adhesion promoter is one or more combinations of epoxy silanes, phosphate esters, and titanates.

9. The high-performance composite material that cures at room temperature according to claim 1, characterized in that, The curing agent of component B is one or more combinations of aliphatic amine curing agents, aromatic amine curing agents, or polyamide curing agents.

10. A method for preparing a centralizer using the room-temperature curing high-performance composite material according to any one of claims 1-9, characterized in that, Includes the following steps: (1) First, add the weighed coupling agent, accelerator, dispersant and adhesion promoter to the epoxy resin matrix in sequence; during the addition process, turn on the stirring equipment and stir at a speed of 100-300r / min to initially disperse each additive in the epoxy resin matrix. The stirring time is 5-10min to ensure that there is no obvious agglomeration. (2) For fillers, first mix the difficult-to-disperse fillers such as carbon fiber, activated carbon powder, and nano titanium dioxide with the epoxy resin matrix, and use stirring at 500-1000 r / min or ultrasonic dispersion to make a pre-dispersion, so that the carbon fiber and activated carbon powder are evenly dispersed and avoid entanglement or agglomeration; then, add the remaining fillers to the above mixture according to the proportion, gradually increase the stirring speed to 300-500 r / min, and continue stirring for 20-30 min to make the fillers and resin matrix fully mixed, ensuring that the fillers are evenly dispersed in the resin without obvious precipitation or agglomeration; (3) Add the weighed defoamer to the mixed system and stir at 200-400 r / min for 5-10 min to eliminate the bubbles generated during the mixing process and make the A component system more uniform and stable. (4) Sandblast the target location of the sleeve to be installed with the centralizer until the surface roughness reaches Ra>6μm; (5) Fix the custom mold onto the surface of the sandblasted sleeve to ensure that the mold fits tightly against the sleeve; (6) Mix the A component obtained in step (1)-(3) with the curing agent B component according to the mass ratio of A component to B component 100:(1-16.5). Stir mechanically at a speed of 200-300r / min for 2-5 minutes until the system color is uniform. (7) Quickly inject the well-mixed composite material into the fixed mold, maintaining a uniform injection speed to avoid air bubbles being trapped; (8) Allow the composite material in the mold to cure naturally in an environment of -10℃ to 45℃. The curing time is usually 5-30h. After the composite material is completely cross-linked and cured, remove the mold to obtain the target straightener product.

Images