A formulation for spraying the inner wall of an expansion tube in oil drilling, its preparation method, and its application.

Abstract

This application pertains to the field of expansion tubes used in oil drilling, and discloses a spraying formulation for the inner wall of an expansion tube used in oil drilling and its preparation method. The spraying formulation comprises 30-40 parts by weight of phenolic resin, 5-8 parts by weight of graphite lubricant, 2-5 parts by weight of a nanoparticle composition, 3-8 parts by weight of anionic fluorocarbon surfactant, and 3-8 parts by weight of a cationic polymeric dispersant. The nanoparticle composition is composed of nano-zinc oxide and nano-silica in a mass ratio of (1-2):3. This application improves the toughness and strength of the coating by adding nano-zinc oxide and nano-silica to the spraying formulation; provides lubrication by adding graphite lubricant; and enhances the dispersibility of the particles in the phenolic resin and strengthens the cross-linking between the particles and the phenolic resin by coating the surfaces of the three types of particles with anionic fluorocarbon surfactant and dispersing the cationic polymeric dispersant between the particles.

Description

Technical Field

[0001] This application belongs to the field of expansion tubes used in oil drilling, and particularly relates to a coating agent for the inner wall of an expansion tube used in oil drilling, its preparation method and application. Background Technology

[0002] As oil extraction progresses into the mid-to-late stages of oilfield development, wells frequently experience damage during production, severely impacting normal oil extraction operations. Therefore, researching and promoting new and effective well workover techniques is urgently needed. Expandable tubing technology has played a role in addressing this challenge. Currently, expandable tubing has been successfully applied offshore, saving significant amounts of raw materials. Using expandable tubing for well completion can substantially increase oil well production and reduce drilling and completion costs.

[0003] To reduce the operational pressure of expansion tubes and enhance lubrication between their inner walls and expansion tools, a coating layer is often added to the inner wall of the expansion tube. In the existing technology, the main raw material of this coating is resin. To prevent the coating from tearing locally or cracking in a fish-scale pattern during the expansion process, which would affect the use of the expansion tube, technicians often choose to add a variety of lubricating materials to the coating raw materials. However, the effect is limited. Summary of the Invention

[0004] In order to overcome the defects of the existing technology, the purpose of this application is to provide a coating agent for the inner wall of an expansion tube in oil drilling and its preparation method, so as to improve the overall toughness and strength of the coating and prevent the inner wall coating from tearing, forming cracks and peeling during the expansion of the expansion tube.

[0005] To achieve the above objectives, this application provides the following technical solution:

[0006] An oil drill expansion tube inner wall spraying formulation includes: 30-40 parts by weight of phenolic resin, 5-8 parts by weight of graphite lubricant, 2-5 parts by weight of nanoparticle composition, 3-8 parts by weight of anionic fluorocarbon surfactant and 3-8 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of (1-2):3.

[0007] Furthermore, the spraying formulation includes: 36 parts by weight of phenolic resin, 7 parts by weight of graphite lubricant, 4 parts by weight of nanoparticle composition, 5 parts by weight of anionic fluorocarbon surfactant and 5 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of 1:3.

[0008] Furthermore, the specific surface area of ​​nano-silica is 150-200 m². 2 / g.

[0009] Furthermore, the specific surface area of ​​nano-zinc oxide is 12-24 m². 2 / g.

[0010] Secondly, this application discloses a method for preparing a coating agent for spraying onto the inner wall of an expansion tube in oil drilling, comprising:

[0011] Weigh out the graphite lubricant, nano zinc oxide and nano silica according to the preset mass ratio and mix them evenly to obtain particulate mixture A. Heat particulate mixture A.

[0012] The anionic fluorocarbon surfactant was prepared into a solution with a predetermined mass fraction and then atomized and sprayed onto the heated particulate mixture A.

[0013] The sprayed particulate mixture A is mixed with a predetermined mass fraction of cationic polymeric dispersant to obtain mixture B;

[0014] Mixture B is mixed with a predetermined mass of phenolic resin to obtain a spraying formulation.

[0015] Furthermore, the preset mass fractions include:

[0016] The composition comprises 30-40 parts by weight of phenolic resin, 5-8 parts by weight of graphite lubricant, 2-5 parts by weight of nanoparticle composition, 3-8 parts by weight of anionic fluorocarbon surfactant and 3-8 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of (1-2):3.

[0017] Furthermore, the preset mass fractions include:

[0018] The composition comprises 36 parts by weight of phenolic resin, 7 parts by weight of graphite lubricant, 4 parts by weight of nanoparticle composition, 5 parts by weight of anionic fluorocarbon surfactant and 5 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of 1:3.

[0019] Further, heating the particulate mixture A includes:

[0020] Heat the particulate mixture A to 200-280℃.

[0021] Thirdly, this application discloses the application of a spraying agent for the inner wall of an expansion tube in oil drilling, wherein the inner wall of the expansion tube is sprayed with the above-mentioned spraying agent.

[0022] Furthermore, applications include:

[0023] The spraying formulation is prepared into a solution with a mass fraction of 30-40% using ketone, ester, or alcohol resin solvents;

[0024] The ethanol and the solution were mixed and diluted at a volume ratio of 1:10 to obtain a diluted solution.

[0025] The diluted solution is atomized and sprayed using high-pressure air at 1.05-1.1 times atmospheric pressure, and the thickness of the finished coating is 2-5μm.

[0026] One to two hours after spraying, use dehumidified high-pressure air at 1.05 to 1.1 times atmospheric pressure to dry the sprayed area.

[0027] The technical effects and advantages of this application are as follows:

[0028] 1. This application adds nano-silica and nano-zinc oxide to the spraying formulation. The nano-silica has a flocculent and network-like quasi-granular structure, high strength, and good anti-aging properties. The nano-zinc oxide has a hexagonal crystal system or spherical particle structure, with good activity and good fluidity. When the two are compounded in an appropriate ratio and added to phenolic resin, they can act as stress concentration centers in the phenolic resin, inducing a large number of crazes and shear bands, consuming and absorbing a large amount of energy generated by the phenolic resin during the curing process. When the expansion tube expands, the internal coating is stretched accordingly. This process reduces the generation of internal stress, which is beneficial to improving the overall toughness and strength and preventing the generation of fish-scale cracks.

[0029] 2. This application adds graphite lubricant to the spraying formulation to achieve a lubricating effect. It is doped with nano-silica and nano-zinc oxide. By coating the surface of the three particles with anionic fluorocarbon surfactant and dispersing cationic polymeric dispersant between the particles, it is beneficial to improve the dispersibility of the particles in phenolic resin, enhance the degree of cross-linking between the particles and phenolic resin, and further ensure that the inner wall coating does not tear, develop fish-scale cracks and peel off during the expansion tube expansion process.

[0030] Other features and advantages of this application will be set forth in the description which follows, and will be apparent in part from the description, or may be learned by practicing the application. The objectives and other advantages of this application may be realized and obtained by means of the structures pointed out in the description, claims and drawings. Attached Figure Description

[0031] Figure 1 This is a flowchart illustrating a method for preparing a coating agent for spraying onto the inner wall of an expansion tube in an oil drilling rig, as described in this application. Detailed Implementation

[0032] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0033] This application provides a coating formulation for the inner wall of an expansion tube used in oil drilling, comprising: 30-40 parts by weight of phenolic resin, 5-8 parts by weight of graphite lubricant, 2-5 parts by weight of nanoparticle composition, 3-8 parts by weight of anionic fluorocarbon surfactant and 3-8 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of (1-2):3.

[0034] In some embodiments of this application, the spraying formulation includes: 36 parts by weight of phenolic resin, 7 parts by weight of graphite lubricant, 4 parts by weight of nanoparticle composition, 5 parts by weight of anionic fluorocarbon surfactant and 5 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silica in a mass ratio of 1:3.

[0035] It should be noted that nano-silica has a flocculent and network-like quasi-granular structure, high strength, and good anti-aging properties. Nano-zinc oxide has a hexagonal crystal system or spherical particle structure, with good activity and fluidity. When the two are compounded in an appropriate ratio and added to phenolic resin, they can act as stress concentration centers within the phenolic resin, inducing a large number of crazes and shear bands, consuming and absorbing a large amount of energy generated by the phenolic resin during curing, which is beneficial to improving the overall toughness and strength. When the expansion tube expands, the internal coating is stretched accordingly, which reduces the generation of internal stress and helps prevent the formation of fish-scale cracks. Graphite lubricant plays the main lubricating role and is doped with nano-silica and nano-zinc oxide. Anionic fluorocarbon surfactants are coated on the surface of the three particles, and cationic polymeric dispersants are dispersed between the particles, which helps to improve the dispersibility of the particles in the phenolic resin, enhance the degree of cross-linking between the particles and the phenolic resin, and further ensure that the inner wall coating does not tear, develop fish-scale cracks, or peel off during the expansion tube expansion process.

[0036] In some embodiments of this application, the specific surface area of ​​nano-silica is 150-200 m². 2 / g.

[0037] In some embodiments of this application, the specific surface area of ​​nano-zinc oxide is 12-24 m². 2 / g.

[0038] Secondly, such as Figure 1As shown, this application discloses a method for preparing a coating agent for spraying onto the inner wall of an expansion tube in oil drilling, comprising:

[0039] Weigh out the graphite lubricant, nano zinc oxide and nano silica according to the preset mass ratio and mix them evenly to obtain particulate mixture A. Heat particulate mixture A.

[0040] The anionic fluorocarbon surfactant was prepared into a solution with a predetermined mass fraction and then atomized and sprayed onto the heated particulate mixture A.

[0041] The sprayed particulate mixture A is mixed with a predetermined mass fraction of cationic polymeric dispersant to obtain mixture B;

[0042] Mixture B is mixed with a predetermined mass of phenolic resin to obtain a spraying formulation.

[0043] In some embodiments of this application, the preset mass fraction includes:

[0044] The composition comprises 30-40 parts by weight of phenolic resin, 5-8 parts by weight of graphite lubricant, 2-5 parts by weight of nanoparticle composition, 3-8 parts by weight of anionic fluorocarbon surfactant and 3-8 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of (1-2):3.

[0045] In some embodiments of this application, the preset mass fraction includes:

[0046] The composition comprises 36 parts by weight of phenolic resin, 7 parts by weight of graphite lubricant, 4 parts by weight of nanoparticle composition, 5 parts by weight of anionic fluorocarbon surfactant and 5 parts by weight of cationic polymeric dispersant, wherein the nanoparticle composition is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of 1:3.

[0047] In some embodiments of this application, heating the particulate mixture A includes:

[0048] Heat the particulate mixture A to 200-280℃.

[0049] Thirdly, this application discloses the application of a spraying agent for the inner wall of an expansion tube in oil drilling, wherein the inner wall of the expansion tube is sprayed with the above-mentioned spraying agent.

[0050] In some embodiments of this application, the applications include:

[0051] The spraying formulation is prepared into a solution with a mass fraction of 30-40% using ketone, ester, or alcohol resin solvents;

[0052] The ethanol and the solution were mixed and diluted at a volume ratio of 1:10 to obtain a diluted solution.

[0053] The diluted solution is atomized and sprayed using high-pressure air at 1.05-1.1 times atmospheric pressure, and the thickness of the finished coating is 2-5μm.

[0054] One to two hours after spraying, use dehumidified high-pressure air at 1.05 to 1.1 times atmospheric pressure to dry the sprayed area.

[0055] To better illustrate this solution, the following embodiments and comparative examples are also provided.

[0056] Example 1

[0057] The following parts by weight are used to prepare the oil drilling coating for spraying onto the inner wall of the expansion tube:

[0058] The composition comprises 36 parts phenolic resin, 7 parts graphite lubricant, 4 parts nanoparticle composition, 5 parts anionic fluorocarbon surfactant, and 5 parts cationic polymeric dispersant. The nanoparticle composition is composed of nano-zinc oxide and nano-silica in a 1:3 ratio, and the specific surface area of ​​the nano-silica is 150-200 m² / g. 2 / g, the specific surface area of ​​nano zinc oxide is 12-24m². 2 / g.

[0059] In this embodiment, the preparation method of the oil drilling expansion tube inner wall spraying agent includes the following steps:

[0060] (1) Weigh out the graphite lubricant, nano zinc oxide and nano silicon dioxide according to the specified weight parts, mix the three evenly to form particulate mixture A, heat particulate mixture A to 255°C, prepare the specified weight parts of anionic fluorocarbon surfactant into a solution through a solvent, and spray it onto the heated particulate mixture A to promote the external coating of particulate mixture A with anionic fluorocarbon surfactant.

[0061] (2) Mix the particle mixture coated with anionic fluorocarbon surfactant with a specified weight of cationic polymeric dispersant until uniform. The cationic polymeric dispersant is dispersed between the particles of the particle mixture to form mixture B. Add mixture B to a specified weight of phenolic resin and mix until uniform.

[0062] Example 2

[0063] The following raw materials are used to prepare a coating for the inner wall of the expansion tube of an oil drilling rig, in the following weight proportions: 30 parts phenolic resin, 5 parts graphite lubricant, 2 parts nanoparticle composition, 3 parts anionic fluorocarbon surfactant, and 3 parts cationic polymeric dispersant. The nanoparticle composition consists of nano-zinc oxide and nano-silica in a 2:3 ratio, and the specific surface area of ​​the nano-silica is 150-200 m² / g. 2 / g, the specific surface area of ​​nano zinc oxide is 12-24m². 2 / g.

[0064] The oil drilling method described in this embodiment uses a method for preparing a coating agent sprayed onto the inner wall of an expansion tube, which includes the following steps:

[0065] (1) Weigh out the graphite lubricant, nano zinc oxide and nano silicon dioxide according to the specified weight parts, mix the three evenly to form particulate mixture A, heat particulate mixture A to 200°C, prepare the specified weight parts of anionic fluorocarbon surfactant into a solution through a solvent, and spray it onto the heated particulate mixture A to promote the external coating of particulate mixture A with anionic fluorocarbon surfactant.

[0066] (2) Mix the particle mixture coated with anionic fluorocarbon surfactant with a specified weight of cationic polymeric dispersant until uniform. The cationic polymeric dispersant is dispersed between the particles of the particle mixture to form mixture B. Add mixture B to a specified weight of phenolic resin and mix until uniform.

[0067] Example 3

[0068] The following raw materials are used to prepare a coating for the inner wall of an expansion tube for oil drilling: 40 parts phenolic resin, 8 parts graphite lubricant, 5 parts nanoparticle composition, 8 parts anionic fluorocarbon surfactant, and 8 parts cationic polymeric dispersant. The nanoparticle composition consists of nano-zinc oxide and nano-silica in a 1:3 ratio, with the nano-silica having a specific surface area of ​​150-200 m². 2 / g, the specific surface area of ​​nano zinc oxide is 12-24m². 2 / g.

[0069] In this embodiment, the oil drill uses a method for preparing a coating agent sprayed onto the inner wall of an expansion tube, which includes the following steps:

[0070] (1) Weigh out the graphite lubricant, nano zinc oxide and nano silicon dioxide according to the specified weight parts, mix the three evenly to form a granular mixture A, heat the granular mixture A to 280°C, prepare the specified weight parts of anionic fluorocarbon surfactant into a solution through a solvent, and spray it onto the heated granular mixture A to promote the external coating of the granular mixture A with anionic fluorocarbon surfactant.

[0071] (2) Mix the particle mixture coated with anionic fluorocarbon surfactant with a specified weight of cationic polymeric dispersant until uniform. The cationic polymeric dispersant is dispersed between the particles of the particle mixture to form mixture B. Add mixture B to a specified weight of phenolic resin and mix until uniform.

[0072] Comparative Example 1

[0073] The nanoparticle composition of Comparative Example 1 is composed of nano zinc oxide and nano silicon dioxide in a mass ratio of 1:1, and the other components are the same as those in Example 1.

[0074] The preparation method of Comparative Example 1 is the same as that of Example 1.

[0075] Comparative Example 2

[0076] The raw materials used in Comparative Example 2 were exactly the same as those used in Example 1.

[0077] The preparation method of Comparative Example 2 includes the following steps: weigh each component raw material according to the specified weight parts, mix each component raw material evenly, and then place it in a solvent to prepare a solution with a mass fraction of 35%.

[0078] The formulations prepared in Examples 1-3 and Comparative Examples 1-2 were subjected to performance tests, with existing phenolic resin raw materials serving as a blank control group. The test results are shown in Table 1.

[0079] Table 1

[0080] Grouping compressive strength Tensile strength Blank control group 74MPa 15.43MPa Example 1 127MPa 23.67MPa Example 2 116MPa 22.15MPa Example 3 121MPa 22.46MPa Comparative Example 1 97MPa 18.44MPa Comparative Example 2 86MPa 16.71MPa

[0081] As can be seen from Table 1, the compressive strength and tensile strength of the preparations obtained in Examples 1-3 are significantly improved compared with the control group and Comparative Examples 1-2.

[0082] Using the formulations prepared in Examples 1-3 and Comparative Examples 1-2, five expansion tubes with built-in coatings were prepared by spraying the inner wall of the expansion tube. The steps are as follows: The oil drill's expansion tube inner wall spraying formulation was prepared into a 35% (w / w) solution in a solvent. The solution was diluted by mixing ethanol and the spraying formulation solution at a volume ratio of 1:10. The diluted solution was atomized and sprayed using high-pressure air at 1.05-1.1 times atmospheric pressure. The thickness of the coating after spraying was 2-5 μm. One to two hours after spraying, the inner wall of the tube was dried with dehumidified high-pressure air at 1.05-1.1 times atmospheric pressure.

[0083] Expansion tests were conducted on the prepared expansion tubes. The expansion pressure was reduced from 28 MPa to 24 MPa, and the pressure was maintained at 24-25 MPa during the expansion of 15 meters of expansion tube. After the expansion test, the expanded expansion tubes were inspected, and the test results are as follows:

[0084] Table 2

[0085]

[0086] As can be seen from Table 2, although the formulations prepared in Examples 1-3 have a small amount of lubricant and no lubricant adhesion enhancer is added, they can still ensure that there are no cracks or fish-scale-like peeling on the inner surface of the expansion tube.

[0087] Finally, it should be noted that the above description is only a preferred embodiment of this application and is not intended to limit this application. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. An oil drilling using an inside wall spraying preparation of an expansion pipe, characterized in that, It comprises: phenolic resin 30-40 parts by mass, graphite lubricant 5-8 parts by mass, nanoparticle composition 2-5 parts by mass, anionic fluorocarbon surfactant 3-8 parts by mass, and cationic high molecular dispersant 3-8 parts by mass, wherein the nanoparticle composition is composed of nano-zinc oxide and nano-silicon dioxide in a mass ratio of (1-2):3; The preparation method of the spraying preparation comprises: According to the preset mass, graphite lubricant, nano-zinc oxide and nano-silicon dioxide are weighed and uniformly mixed to obtain a particle mixture A, and the particle mixture A is heated; The anionic fluorocarbon surfactant of the preset mass is configured into a solution and sprayed on the heated particle mixture A; The particle mixture A after spraying is mixed with the cationic high molecular dispersant of the preset mass to obtain a mixture B; The mixture B is mixed with the phenolic resin of the preset mass to obtain the spraying preparation.

2. A petroleum drilling using an inside wall spraying preparation of an expansion pipe according to claim 1, characterized in that, It comprises: phenolic resin 36 parts by mass, graphite lubricant 7 parts by mass, nanoparticle composition 4 parts by mass, anionic fluorocarbon surfactant 5 parts by mass, and cationic high molecular dispersant 5 parts by mass, wherein the nanoparticle composition is composed of nano-zinc oxide and nano-silicon dioxide in a mass ratio of 1:

3.

3. The inner wall spraying preparation for the expanded pipe used in oil drilling according to claim 1, characterized in that, The specific surface area of the nanosilica is 150-200 m 2 / g.

4. The inner wall spraying preparation for the expanded pipe used in oil drilling according to claim 1, characterized in that, The specific surface area of the nano-zinc oxide is 12-24 m 2 / g.

5. A method of preparing a formulation for spraying the interior wall of an expandable pipe used in oil drilling according to any one of claims 1 to 4, characterized in that, It comprises: According to the preset mass, graphite lubricant, nano-zinc oxide and nano-silicon dioxide are weighed and uniformly mixed to obtain a particle mixture A, and the particle mixture A is heated; The anionic fluorocarbon surfactant of the preset mass is configured into a solution and sprayed on the heated particle mixture A; The particle mixture A after spraying is mixed with the cationic high molecular dispersant of the preset mass to obtain a mixture B; The mixture B is mixed with the phenolic resin of the preset mass to obtain the spraying preparation.

6. The method of claim 5, wherein the method further comprises the step of: The preset mass comprises: ​ phenolic resin 30-40 parts by mass, graphite lubricant 5-8 parts by mass, nanoparticle composition 2-5 parts by mass, anionic fluorocarbon surfactant 3-8 parts by mass, and cationic high molecular dispersant 3-8 parts by mass, wherein the nanoparticle composition is composed of nano-zinc oxide and nano-silicon dioxide in a mass ratio of (1-2):

3.

7. The method of claim 5, wherein the method further comprises the step of: The preset mass comprises: ​ phenolic resin 36 parts by mass, graphite lubricant 7 parts by mass, nanoparticle composition 4 parts by mass, anionic fluorocarbon surfactant 5 parts by mass, and cationic high molecular dispersant 5 parts by mass, wherein the nanoparticle composition is composed of nano-zinc oxide and nano-silicon dioxide in a mass ratio of 1:

3.

8. The method of claim 5, wherein the method further comprises the step of: The heating of the particle mixture A comprises: ​ The particle mixture A is heated to 200-280℃.

9. Use of an inside wall spray formulation for an expandable tubular for oil drilling, characterized in that The spraying preparation according to any one of claims 1-4 is used to spray the inner wall of the expanded pipe.

10. The use of a petroleum drilling employing a spray-on formulation for the interior wall of an expansion pipe according to claim 9, characterized in that, It comprises: The spraying preparation is configured into a solution with a mass fraction of 30-40% by using a ketone, ester or alcohol resin solvent; The ethanol and the solution are mixed and diluted at a volume ratio of 1:10 to obtain a diluted solution; The diluted solution is atomized and sprayed by using high-pressure air at 1.05-1.1 times of atmospheric pressure, and the thickness of the coating after spraying is 2-5 μm; After 1-2 hours after spraying, the sprayed part is blown dry by using high-pressure air at 1.05-1.1 times of atmospheric pressure after dehumidification.

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