A sucker rod surface coating process and corrosion-resistant sucker rod

Abstract

The present invention belongs to the technical field of sucker rods, and specifically relates to a sucker rod surface coating process and a corrosion-resistant sucker rod; the sucker rod head adopts a hot-melt-coated nickel-based alloy powder spraying process, and the sucker rod body is coated with corrosion-resistant materials; the corrosion-resistant materials include the following raw materials, in parts by mass: 30-50 parts of polypropylene, 60-80 parts of modified epoxy resin, 3-5 parts of antioxidant, 5-10 parts of silicon carbide, 1-5 parts of silane coupling agent, and 1-5 parts of stearic acid. The present invention forms a complete isolation layer on the sucker rod to protect the sucker rod from being corroded by oil well production fluid; the corrosion-resistant materials used are reasonably proportioned, and the coating layer formed on the surface of the sucker rod has strong adhesion, good wear resistance, and good anti-corrosion effect.

Description

Technical Field

[0001] The invention belongs to the technical field of sucker rods, and in particular relates to a sucker rod surface coating process and a corrosion-resistant sucker rod. Background Art

[0002] The sucker rod is a slender rod, connected to the bare rod at the top and the oil pump at the bottom. The sucker rod can transmit the power of the ground equipment to the downhole oil pump. The up and down movement of the sucker rod drives the piston movement of the downhole oil pump, and then pumps the oil layer fluid to the ground.

[0003] In the middle and late stages of oilfield development, the water content in the oil well output fluid is getting higher and higher, accompanied by corrosive media such as carbon dioxide, hydrogen sulfide and bacteria. The harsh working environment makes the corrosion problem of the sucker rod more serious, and the service life of the sucker rod is greatly affected. At present, the common methods of electroplating or chemical plating on the surface of the sucker rod and adding corrosion inhibitors to the wellbore are used to achieve the purpose of corrosion prevention.

[0004] Yi Yanan (Oilfield Pipe and Rod Corrosion Mechanism and Application of Chemical Anticorrosion Technology [J]. China Equipment Engineering, 2012, (04): 46-48.) found that in the Gudong Oilfield, high-mineralization formation water and acidic gases such as H2S, CO2, and depolarizer dissolved oxygen promote each other and accelerate metal corrosion; therefore, the MYD-5 type corrosion inhibitor was synthesized to reduce the concentration of H2S and CO2 to reduce the reaction rate. At the same time, the corrosion inhibitor will form a dense protective film on the metal surface, thereby reducing the contact between the metal and dissolved oxygen. The corrosion inhibition rate is above 75%, and it has the characteristics of slow release. When the pumping rod is working, due to the inclination of the oil well, there is sliding friction between the wire rope and the oil pipe, and the rod and pipe wear problem is relatively serious. Therefore, although the addition of corrosion inhibitors can achieve the purpose of corrosion protection, it cannot solve the problem of increased wear of the pumping rod.

[0005] In summary, it is urgent to eliminate and slow down the corrosion and wear failure of sucker rods. Summary of the invention

[0006] Existing sucker rods have serious problems of corrosion and wear failure. In order to solve this problem, the present invention provides a sucker rod surface coating process and a corrosion-resistant sucker rod.

[0007] In order to achieve the purpose of the present invention, the present invention adopts the following technical solutions:

[0008] In a first aspect, the present invention provides a sucker rod surface coating process, wherein the sucker rod surface coating process mainly includes coating a sucker rod body, and the specific steps are as follows:

[0009] S1: Pretreatment: Clean and polish the surface of the sucker rod;

[0010] S2: Fix the pretreated sucker rod and inject the corrosion-resistant material into the sucker rod body;

[0011] Wherein, the corrosion-resistant material includes the following raw materials, measured by mass:

[0012] 30-50 parts of polypropylene, 60-80 parts of modified epoxy resin, 3-5 parts of antioxidant, 5-10 parts of silicon carbide, 1-5 parts of silane coupling agent, and 1-5 parts of stearic acid.

[0013] Preferably, the preparation method of the modified epoxy resin is as follows:

[0014] (1) Liquid paraffin, hexadecyltrimethylammonium bromide, ethanol aqueous solution, and potassium hydroxide aqueous solution are stirred evenly, and ethyl orthosilicate is added to react. After the reaction is completed, the hollow mesoporous silica is washed with alcohol, filtered, dried, and calcined to obtain the hollow mesoporous silica;

[0015] (2) dissolving oil-soluble oleic acid imidazoline and water-soluble oleic acid imidazoline in anhydrous ethanol, adding hexadecyltrimethylammonium bromide and stirring evenly, adding hollow mesoporous silica, ultrasonically dispersing, vacuum impregnating, washing with alcohol, filtering, and drying to obtain microcapsules;

[0016] (3) Mix rigid alcohol, 2,2-bis-(4-glycolylaminophenyl)propane, diethylenetriamine, carboxyl-terminated nitrile rubber, zinc acetylacetonate and anhydrous ethanol evenly, heat to react, add silane coupling agent and microcapsules to continue the reaction, and vacuum cure after the reaction to obtain a modified epoxy resin.

[0017] Preferably, in (1), the mass ratio of liquid paraffin: hexadecyltrimethylammonium bromide: ethyl orthosilicate is 1:3-5:1-2; and the reaction time is 3-4h.

[0018] Preferably, in (2), the mass ratio of oil-soluble oleic acid imidazoline to water-soluble oleic acid imidazoline is 1:4-5; the mass of the hollow mesoporous silica is 25%-40% of the total mass of the oil-soluble oleic acid imidazoline and the water-soluble oleic acid imidazoline.

[0019] Preferably, in (3), the mass ratio of rigid alcohol: 2,2-bis-(4-glycolyloxyphenyl)propane: diethylenetriamine is 1: 0.82-2.45: 0.2-0.3; the carboxyl-terminated nitrile rubber accounts for 10%-12% of the total mass of the rigid alcohol, the 2,2-bis-(4-glycolyloxyphenyl)propane and the diethylenetriamine; the mass of the zinc acetylacetonate accounts for 5%-8% of the mass of the 2,2-bis-(4-glycolyloxyphenyl)propane; and the mass of the microcapsule is 5-10% of the total mass of the rigid alcohol and the 2,2-bis-(4-glycolyloxyphenyl)propane.

[0020] Preferably, in (3), the preparation method of the rigid alcohol is as follows:

[0021] 4,4',4''-methylenetriphenol, ethylene carbonate, potassium carbonate and N,N-dimethylformamide are mixed evenly, heated to react, and after the reaction is completed, washed with water, filtered and dried to obtain rigid alcohol.

[0022] Preferably, in terms of mass ratio, 4,4',4''-methylenetriphenol:ethylene carbonate = 1:0.95-1.2; the mass of the potassium carbonate is 1%-3% of the mass of the 4,4',4''-methylenetriphenol; and the mass of the microcapsules is 5-10% of the total mass of the 4,4',4''-methylenetriphenol and the ethylene carbonate.

[0023] Preferably, the reaction temperature is 70-80°C and the reaction time is 10-12h.

[0024] The preparation process of the rigid alcohol is as follows:

[0025]

[0026] Preferably, in (3), the vacuum curing temperature is as follows:

[0027] First, heat to 60°C and keep for 2-3h, then continue to heat to 120°C and react for 2-4h, finally heat to 160°C and react for 2-4h, and cool to room temperature.

[0028] Preferably, the sucker rod surface coating process also includes coating the sucker rod head, and the sucker rod head adopts a hot melt coating nickel-based alloy powder spraying process.

[0029] In a second aspect, the present invention further provides a corrosion-resistant sucker rod, which is treated with corrosion protection by using the above-mentioned sucker rod surface coating process.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] (1) The present invention adds microcapsules to the epoxy resin matrix, which can produce extremely strong interactions with the resin molecules. The dense nanostructure has a strong barrier property against corrosive particles, preventing the corrosive medium from penetrating into the metal surface. The hardness of silicon dioxide is relatively high, which can reduce the wear and scratches on the metal surface, further improving the wear resistance of the corrosion-resistant material. Silicon dioxide can form a gradually transitioning intermediate layer between the metal and the coating, reducing the interfacial stress caused by the large difference in material properties, making the interface bonding more stable.

[0032] (2) The microcapsules added in the present invention can rupture when the sucker rod coating is subjected to external force, release the corrosion inhibitor contained therein, and form a protective film on the coating or the metal surface of the sucker rod, thereby preventing the oil phase and the water phase from corroding the sucker rod, thereby protecting the metal, extending the service life of the sucker rod, and reducing the replacement cycle;

[0033] (3) The present invention introduces rigid alcohol into the epoxy resin to increase the hardness and wear resistance of the corrosion-resistant material, so that it can withstand external mechanical impact and friction during use; the cured epoxy resin has a three-dimensional network structure, a high cross-linking density, a large internal stress and a hard and brittle texture. The material will bend and twist with the sucker rod during use and is prone to cracking, so adding a toughening agent has a good toughening effect on the epoxy resin;

[0034] (4) The present invention adopts a hot-melt nickel-based alloy powder spraying process on the sucker rod head and covers the sucker rod body with corrosion-resistant materials to form a complete isolation layer to protect the sucker rod from being corroded by oil well production fluids; the corrosion-resistant materials used are reasonably proportioned, and the coating layer formed on the surface of the sucker rod has strong adhesion, good wear resistance and good anti-corrosion effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 This is the SEM image of the microcapsule of Example 2 of the present invention. DETAILED DESCRIPTION

[0036] The technical solution of the present invention is explained in detail below with reference to several representative embodiments of the present invention.

[0037] The experimental methods used in the following examples are conventional methods unless otherwise specified. The materials, reagents, etc. used in the following examples are all commercially available unless otherwise specified.

[0038] The antioxidant used in the present invention is an antioxidant commonly used in polymer materials, such as BHT (2,6-tert-butyl-p-cresol), antioxidant 1010 (tetra(alkylhydroxy)benzoate), etc.; the silane coupling agent used in the present invention is a commonly used silane coupling agent, such as silane coupling agent KH-560, silane coupling agent KH-570, etc.; the antioxidant used in the following embodiments is antioxidant 1010; the silane coupling agent used is silane coupling agent KH-570; the carboxyl-terminated nitrile rubber used is CTBN-1300X8, with a molecular weight of 3550; the polypropylene used is commercially available polypropylene, with a melt index of 2.2 g / 10 min, which will not be described in detail here.

[0039] Example 1

[0040] A sucker rod surface coating process, the specific steps are as follows:

[0041] S1: Pretreatment: Clean and polish the surface of the sucker rod;

[0042] S2: Fix the pretreated sucker rod and inject the corrosion-resistant material into the sucker rod body;

[0043] S3: The sucker rod head adopts hot-melt cladding nickel-based alloy powder spraying process.

[0044] Wherein, the corrosion-resistant material includes the following raw materials, measured by mass:

[0045] 30 parts of polypropylene, 70 parts of modified epoxy resin, 4 parts of antioxidant, 6 parts of silicon carbide, 2 parts of silane coupling agent, 3 parts of stearic acid;

[0046] The preparation method of the modified epoxy resin is as follows:

[0047] (1) 2 g of liquid paraffin, 7 g of hexadecyltrimethylammonium bromide, 100 mL of 60% ethanol aqueous solution, and 6 mL of 2 mol / L potassium hydroxide aqueous solution were mixed, stirred for 20 min, and then 3 g of ethyl orthosilicate was added to react for 3.5 h. After the reaction, the mixture was washed with anhydrous ethanol for 3 times, filtered, dried, and calcined at 600 °C for 7 h to obtain hollow mesoporous silica;

[0048] (2) Dissolve 2 g of oil-soluble oleic acid imidazoline and 8 g of water-soluble oleic acid imidazoline in 20 mL of 60% anhydrous ethanol, add 2 g of hexadecyltrimethylammonium bromide and stir for 30 min, add 2.5 g of hollow mesoporous silica, ultrasonically disperse for 3 h, put into a vacuum drying oven with a vacuum degree of -0.03 MPa, maintain for 3 h, ultrasonically disperse evenly, repeat 3 times, wash with anhydrous ethanol 3 times, filter, and dry to obtain microcapsules;

[0049] (3) 5.85 g of 4,4',4''-methylenetriphenol, 7.02 g of ethylene carbonate, 0.059 g of potassium carbonate and 35 mL of N,N-dimethylformamide were mixed evenly, heated to 75°C and stirred continuously for 10 h. After the reaction was completed, the rigid alcohol was washed with water, filtered and dried;

[0050] (4) 5 g of rigid alcohol, 4.1 g of 2,2-bis-(4-glycolylamino)propane, 1 g of diethylenetriamine, 1 g of terminal carboxyl nitrile rubber, 0.25 g of zinc acetylacetonate, and 30 mL of anhydrous ethanol were mixed evenly, heated to 80 °C for reaction for 30 min, 0.10 g of silane coupling agent and 0.55 g of microcapsules were added and the reaction was continued for 6 h. After the reaction was completed, it was placed in a vacuum oven, first heated to 60 °C and maintained for 2 h, then heated to 120 °C for reaction for 3 h, and finally heated to 160 °C for reaction for 3 h, and cooled to room temperature to obtain a modified epoxy resin.

[0051] Example 2

[0052] A sucker rod surface coating process, wherein the specific steps of the coating process are the same as those of Example 1;

[0053] Among them, the corrosion-resistant materials include the following raw materials, calculated by mass:

[0054] 45 parts of polypropylene, 60 parts of modified epoxy resin, 5 parts of antioxidant, 10 parts of silicon carbide, 1 part of silane coupling agent, 5 parts of stearic acid;

[0055] The preparation method of the modified epoxy resin is as follows:

[0056] (1) 2 g of liquid paraffin, 6 g of hexadecyltrimethylammonium bromide, 100 mL of 60% ethanol aqueous solution, and 6 mL of 2 mol / L potassium hydroxide aqueous solution were mixed, stirred for 20 min, and then 4 g of ethyl orthosilicate was added to react for 3.5 h. After the reaction, the mixture was washed with anhydrous ethanol for 3 times, filtered, dried, and calcined at 500 °C for 8 h to obtain hollow mesoporous silica;

[0057] (2) Dissolve 2 g of oil-soluble oleic acid imidazoline and 9 g of water-soluble oleic acid imidazoline in 20 mL of 60% anhydrous ethanol, add 2 g of hexadecyltrimethylammonium bromide and stir for 30 min, add 3.3 g of hollow mesoporous silica, ultrasonically disperse for 3.5 h, put into a vacuum drying oven with a vacuum degree of -0.03 MPa for 3 h, ultrasonically disperse evenly, repeat 3 times, wash with anhydrous ethanol 3 times, filter, and dry to obtain microcapsules. SEM image is shown in Figure 1 ;

[0058] (3) 5.85 g of 4,4',4''-methylenetriphenol, 5.56 g of ethylene carbonate, 0.088 g of potassium carbonate and 35 mL of N,N-dimethylformamide were mixed evenly, heated to 70°C and stirred continuously for 11 hours. After the reaction was completed, the rigid alcohol was washed with water, filtered and dried;

[0059] (4) 5 g of rigid alcohol, 12.25 g of 2,2-bis-(4-glycolylamino)propane, 1.5 g of diethylenetriamine, 2.07 g of carboxyl-terminated nitrile rubber, 0.3 g of zinc acetylacetonate, and 30 mL of anhydrous ethanol were mixed evenly, heated to 80 °C for reaction for 30 min, 0.10 g of silane coupling agent and 0.87 g of microcapsules were added and the reaction was continued for 6 h. After the reaction was completed, the mixture was placed in a vacuum oven, first heated to 60 °C and maintained for 3 h, then heated to 120 °C for reaction for 2 h, and finally heated to 160 °C for reaction for 4 h. The mixture was cooled to room temperature to obtain a modified epoxy resin.

[0060] Example 3

[0061] A sucker rod surface coating process, wherein the specific steps of the coating process are the same as those of Example 1;

[0062] Among them, the corrosion-resistant materials include the following raw materials, calculated by mass:

[0063] 50 parts of polypropylene, 65 parts of modified epoxy resin, 3 parts of antioxidant, 8 parts of silicon carbide, 4 parts of silane coupling agent, 1 part of stearic acid;

[0064] The preparation method of the modified epoxy resin is as follows:

[0065] (1) 2 g of liquid paraffin, 10 g of hexadecyltrimethylammonium bromide, 100 mL of 60% ethanol aqueous solution, and 6 mL of 2 mol / L potassium hydroxide aqueous solution were mixed, stirred for 20 min, and then 3 g of ethyl orthosilicate was added to react for 3 h. After the reaction, the mixture was washed with anhydrous ethanol for 3 times, filtered, dried, and calcined at 550 °C for 6 h to obtain hollow mesoporous silica.

[0066] (2) Dissolve 2 g of oil-soluble oleic acid imidazoline and 10 g of water-soluble oleic acid imidazoline in 20 mL of 60% anhydrous ethanol, add 2 g of hexadecyltrimethylammonium bromide and stir for 30 min, add 4.2 g of hollow mesoporous silica, ultrasonically disperse for 4 h, put into a vacuum drying oven with a vacuum degree of -0.03 MPa, maintain for 3 h, ultrasonically disperse evenly, repeat 3 times, wash with anhydrous ethanol 3 times, filter, and dry to obtain microcapsules;

[0067] (3) 5.85 g of 4,4',4''-methylenetriphenol, 5.85 g of ethylene carbonate, 0.175 g of potassium carbonate and 35 mL of N,N-dimethylformamide were mixed evenly, heated to 80°C and stirred continuously for 12 hours. After the reaction was completed, the rigid alcohol was washed with water, filtered and dried;

[0068] (4) 5 g of rigid alcohol, 6.13 g of 2,2-bis-(4-glycolylamino)propane, 1.24 g of diethylenetriamine, 1.12 g of terminal carboxyl nitrile rubber, 0.4 g of zinc acetylacetonate, and 30 mL of anhydrous ethanol were mixed evenly, heated to 80 °C for reaction for 30 min, 0.10 g of silane coupling agent and 0.89 g of microcapsules were added and the reaction was continued for 6 h. After the reaction was completed, the mixture was placed in a vacuum oven, first heated to 60 °C and maintained for 3 h, then heated to 120 °C for reaction for 4 h, and finally heated to 160 °C for reaction for 2 h. The mixture was cooled to room temperature to obtain a modified epoxy resin.

[0069] Example 4

[0070] A sucker rod surface coating process, wherein the specific steps of the coating process are the same as those of Example 1;

[0071] Among them, the corrosion-resistant materials include the following raw materials, calculated by mass:

[0072] 35 parts of polypropylene, 80 parts of modified epoxy resin, 3 parts of antioxidant, 5 parts of silicon carbide, 5 parts of silane coupling agent, 3 parts of stearic acid;

[0073] The preparation method of the modified epoxy resin is as follows:

[0074] (1) 2 g of liquid paraffin, 8 g of hexadecyltrimethylammonium bromide, 100 mL of 60% ethanol aqueous solution, and 6 mL of 2 mol / L potassium hydroxide aqueous solution were mixed, stirred for 20 min, and then 2 g of ethyl orthosilicate was added to react for 4 h. After the reaction, the mixture was washed with anhydrous ethanol for 3 times, filtered, dried, and calcined at 500 °C for 6 h to obtain hollow mesoporous silica;

[0075] (2) Dissolve 2 g of oil-soluble oleic acid imidazoline and 8 g of water-soluble oleic acid imidazoline in 20 mL of 60% anhydrous ethanol, add 2 g of hexadecyltrimethylammonium bromide and stir for 30 min, add 4 g of hollow mesoporous silica, ultrasonically disperse for 3 h, put into a vacuum drying oven with a vacuum degree of -0.03 MPa, maintain for 3 h, ultrasonically disperse evenly, repeat 3 times, wash with anhydrous ethanol 3 times, filter, and dry to obtain microcapsules;

[0076] (3) 5.85 g of 4,4',4''-methylenetriphenol, 6.44 g of ethylene carbonate, 0.117 g of potassium carbonate and 35 mL of N,N-dimethylformamide were mixed evenly, heated to 70°C and stirred continuously for 12 h. After the reaction was completed, the rigid alcohol was washed with water, filtered and dried;

[0077] (4) 5 g of rigid alcohol, 8.17 g of 2,2-bis-(4-glycolylamino)propane, 1.76 g of diethylenetriamine, 1.58 g of carboxyl-terminated nitrile rubber, 0.4 g of zinc acetylacetonate, and 30 mL of anhydrous ethanol were mixed evenly, heated to 80 °C for reaction for 30 min, 0.10 g of silane coupling agent and 1.31 g of microcapsules were added and the reaction was continued for 6 h. After the reaction was completed, the mixture was placed in a vacuum oven, first heated to 60 °C and maintained for 4 h, then heated to 120 °C for reaction for 2 h, and finally heated to 160 °C for reaction for 2 h. The mixture was cooled to room temperature to obtain a modified epoxy resin.

[0078] Comparative Example 1

[0079] A sucker rod surface coating process. The difference between this comparative example and Example 2 is that this comparative example investigates the effect of microcapsule content on the corrosion-resistant material performance. The rest is the same as Example 2, as shown in Table 1.

[0080] Table 1 Microcapsule content

[0081]

[0082] Comparative Example 2

[0083] A sucker rod surface coating process. The difference between this comparative example and Example 2 is that no carboxyl-terminated nitrile rubber CTBN-1300X8 is added to the modified epoxy resin, and the rest is the same as Example 2.

[0084] Comparative Example 3

[0085] A sucker rod surface coating process. The difference between this comparative example and Example 2 is that no rigid alcohol is added to the modified epoxy resin, and the rest is the same as Example 2.

[0086] Mechanical properties test

[0087] The corrosion-resistant materials prepared in the above-mentioned Examples 1 to 4 and Comparative Examples 1 to 3 were subjected to relevant performance tests, and the test results are shown in Table 2.

[0088] Tensile properties: Tested in accordance with GB / T 2567-2021 Test method for properties of resin castings;

[0089] Hardness: Tested in accordance with GB / T 6739-2022 Paints and varnishes - Pencil method for determination of paint film hardness;

[0090] Abrasion resistance: Tested in accordance with GB / T 1768-2006 Determination of abrasion resistance of paints and varnishes - Rotating rubber grinding wheel method;

[0091] Adhesion: Tested in accordance with GB / T 9286-1998 Cross-cut test for paint and varnish films;

[0092] Impact resistance: Tested in accordance with GB / T 1732-2020 Determination of impact resistance of paint films.

[0093] Table 2 Test results

[0094]

[0095] It can be seen from Example 2 and Comparative Example 1 that when the amount of microcapsules added is small, they can be evenly dispersed in the modified epoxy resin, thereby improving the toughness and tensile strength of the corrosion-resistant material; when the amount of microcapsules added is too much, the dispersibility will deteriorate, which will easily cause agglomeration and reduce the tensile strength of the material.

[0096] It can be seen from Example 2 and Comparative Example 2 that the toughening agent CTBN-1300X8 mainly affects the tensile properties and impact resistance of the material. The addition of CTBN-1300X8 enables it to better resist crack propagation and fracture when subjected to stress, thereby improving its impact resistance.

[0097] It can be seen from Example 2 and Comparative Example 3 that the introduction of rigid alcohol can improve the hardness and wear resistance of the material, and can withstand external mechanical impact and friction during use.

[0098] Anti-corrosion performance test

[0099] The anti-corrosion performance of the corrosion-resistant material of the present invention was investigated by the hanging piece weight loss method (corrosive medium: 0.2 g / LH2S+0.2 g / LCO2+2 mol / LNaCl, 25°C, A3 carbon steel, 96 h), as shown in Table 3.

[0100] Table 3 Test results

[0101]

[0102] The above is an exemplary description of the present invention. It should be noted that, without departing from the core of the present invention, any simple deformation, modification or equivalent replacement that can be done by other technicians in this field without expending creative labor falls within the protection scope of the present invention.

Claims

1. A sucker rod surface coating process, characterized in that: The sucker rod surface coating process includes coating the sucker rod body, and the specific steps are as follows: S1: Pretreatment: Clean and polish the surface of the sucker rod; S2: Fix the pretreated sucker rod and inject the corrosion-resistant material into the sucker rod body; The corrosion-resistant material includes the following raw materials, in parts by mass: 30-50 parts of polypropylene, 60-80 parts of modified epoxy resin, 3-5 parts of antioxidant, 5-10 parts of silicon carbide, 1-5 parts of silane coupling agent, 1-5 parts of stearic acid; Wherein, the preparation method of the modified epoxy resin is as follows: (1) Liquid paraffin, hexadecyltrimethylammonium bromide, ethanol aqueous solution, and potassium hydroxide aqueous solution are stirred evenly, and ethyl orthosilicate is added to react. After the reaction is completed, the hollow mesoporous silica is washed with alcohol, filtered, dried, and calcined to obtain the hollow mesoporous silica; (2) dissolving oil-soluble oleic acid imidazoline and water-soluble oleic acid imidazoline in anhydrous ethanol, adding hexadecyltrimethylammonium bromide and stirring evenly, adding hollow mesoporous silica, ultrasonically dispersing, vacuum impregnating, washing with alcohol, filtering, and drying to obtain microcapsules; (3) mixing rigid alcohol, 2,2-bis-(4-glycolylaminophenyl)propane, diethylenetriamine, carboxyl-terminated nitrile rubber, zinc acetylacetonate, and anhydrous ethanol uniformly, heating to react, adding a silane coupling agent and microcapsules to continue the reaction, and vacuum curing after the reaction to obtain a modified epoxy resin; Wherein, in (3), the mass of the microcapsules is 5-10% of the total mass of the rigid alcohol and the 2,2-bis-(4-glycolylaminophenyl)propane; In (3), the preparation method of the rigid alcohol is as follows: 4,4',4''-methylenetriphenol, ethylene carbonate, potassium carbonate and N,N-dimethylformamide are mixed evenly, heated to react, and after the reaction is completed, washed with water, filtered and dried to obtain rigid alcohol.

2. The sucker rod surface coating process according to claim 1, characterized in that: In the above (1), the mass ratio of liquid paraffin: hexadecyltrimethylammonium bromide: ethyl orthosilicate is 1:3-5:1-2; and the reaction time is 3-4h.

3. The sucker rod surface coating process according to claim 1, characterized in that: In (2), the mass ratio of oil-soluble oleic acid imidazoline to water-soluble oleic acid imidazoline is 1:4-5; the mass of the hollow mesoporous silica is 25%-40% of the total mass of the oil-soluble oleic acid imidazoline and the water-soluble oleic acid imidazoline.

4. The sucker rod surface coating process according to claim 1, characterized in that: In (3), the mass ratio of rigid alcohol: 2,2-bis-(4-glycolyloxyphenyl)propane: diethylenetriamine is 1: 0.82-2.45: 0.2-0.3; the carboxyl-terminated nitrile rubber accounts for 10%-12% of the total mass of the rigid alcohol, the 2,2-bis-(4-glycolyloxyphenyl)propane and the diethylenetriamine; the mass of the zinc acetylacetonate accounts for 5%-8% of the mass of the 2,2-bis-(4-glycolyloxyphenyl)propane.

5. The sucker rod surface coating process according to claim 1, characterized in that: In the preparation method of the rigid alcohol, the mass ratio of 4,4',4''-methylenetriphenol to ethylene carbonate is 1:0.95-1.2; the mass of the potassium carbonate is 1%-3% of the mass of the 4,4',4''-methylenetriphenol; the reaction temperature is 70-80°C, and the reaction time is 10-12h.

6. The sucker rod surface coating process according to claim 1, characterized in that: In (3), the vacuum curing temperature is as follows: First, heat to 60°C and keep for 2-3h, then continue to heat to 120°C and react for 2-4h, finally heat to 160°C and react for 2-4h, and cool to room temperature.

7. The sucker rod surface coating process according to claim 1, characterized in that: The sucker rod surface coating process also includes coating the sucker rod head, and the sucker rod head adopts a hot melt coating nickel-based alloy powder spraying process.

8. A corrosion-resistant sucker rod, characterized in that: The corrosion-resistant sucker rod is subjected to anti-corrosion treatment by using the sucker rod surface coating process as described in any one of claims 1 to 7.

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