Corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering and preparation method thereof

Abstract

The present application relates to the technical field of stainless steel material, in particular to a kind of marine engineering corrosion-resistant high-pressure stainless steel pipe and preparation method thereof.The present application provides a kind of preparation method of stainless steel pipe, 1-2% Mo is added in the stainless steel pipe of the present application, Mo makes the corrosion resistance of stainless steel pipe enhanced;0.04-0.06% C is added to enhance the high-pressure resistance of stainless steel pipe.Secondly, a layer of anticorrosive paint is coated on the polished and cleaned stainless steel pipe, the glass scale is modified using trimethylolpropane tris (3-mercaptopropionate) in the present application, so that the glass scale has mercapto group, the mercapto group on the glass scale can occur click reaction with the isocyanate group on modified silicon dioxide, so that the two are compounded together, improve the dispersibility of glass scale in anticorrosive paint, enhance the corrosion resistance of stainless steel pipe.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of stainless steel materials, in particular to a corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering and a preparation method thereof. BACKGROUND

[0002] The ocean contains rich resources such as oil, natural gas, combustible ice and metal ore. With the development of deep-sea resources, the equipment for exploiting ocean resources needs to face problems such as high pressure, seawater corrosion and wet hydrogen sulfide corrosion. The corrosion of stainless steel in seawater is mainly electrochemical corrosion and biological corrosion. When the stainless steel contacts seawater, the seawater will corrode the stainless steel, and at the same time, marine microorganisms will attach and reproduce on the surface of the stainless steel, changing the physical and chemical environment of the surface of the stainless steel, thereby further corroding the stainless steel. Therefore, how to improve the corrosion resistance and high-pressure resistance of the stainless steel pipe becomes more and more important. Adding C in the stainless steel can improve the high-pressure resistance of the stainless steel pipe because carbon has high strength, wear resistance and hardness. However, the corrosion resistance of C is poor, so it is necessary to further improve the corrosion resistance of the stainless steel pipe to make it better resist the harsh environment in the ocean, prolong the service life of the equipment and save resources.

[0003] To solve the above problems, the present application provides a corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering and a preparation method thereof. SUMMARY

[0004] The purpose of the present application is to provide a corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering and a preparation method thereof to solve the problems raised in the background.

[0005] To solve the above technical problems, the present application provides the following technical solutions:

[0006] A preparation method of a corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering, comprising the following steps:

[0007] Step one: take hydrophobic glass flake, modified silica, acetonitrile and triethylamine, ultrasonically disperse, react for 5-6h, filter, wash and dry to obtain a corrosion-resistant composite additive;

[0008] Step two: take epoxy resin, curing agent, corrosion-resistant composite additive and defoaming agent, stir uniformly, stand for 10-20min to obtain a corrosion-resistant coating;

[0009] Step three: take a stainless steel pipe, polish the outer surface, clean and vacuum dry to obtain a pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with the corrosion-resistant coating, then cure at 25-30℃ for 20-24h to obtain a corrosion-resistant and high-pressure-resistant stainless steel pipe.

[0010] More preferably, the preparation method of the modified silica is as follows: taking nano-silica, anhydrous xylene and dimethyltin dilaurate, stirring for 50-70 min to obtain a silica mixture; taking hexamethylene diisocyanate and anhydrous xylene, stirring uniformly, adding the silica mixture under nitrogen protection, heating to 85-95 DEG C, reacting for 4-6 h, washing and drying to obtain the modified silica.

[0011] More preferably, the preparation method of the hydrophobic glass flake is as follows: taking modified glass flake and anhydrous ethanol, ultrasonic dispersion, adding methyltrimethoxysilane, hexadecyltrimethoxysilane and ammonia, stirring for 40-60 min and drying to obtain the hydrophobic glass flake.

[0012] More preferably, the preparation method of the modified glass flake is as follows: taking glass flake and acetonitrile, ultrasonic dispersion, adding trimethylolpropane tris(3-mercaptopropionate), stirring for 3-4 h and drying to obtain the modified glass flake.

[0013] More preferably, the mass ratio of the hydrophobic glass flake and the modified silica is 2:(2.5-4).

[0014] More preferably, in step three, the preparation method of the stainless steel pipe is as follows: taking C, Cr, Mn, Ni, Si, Mo, P, La, S, B and Fe, smelting at 1600-1800 DEG C, then heating to 1850-1900 DEG C, refining for 2-3 h, casting ingot, annealing at 1100-1300 DEG C, keeping for 8-10 h, forging, extruding and annealing to obtain the stainless steel pipe.

[0015] More preferably, the component raw material of the stainless steel pipe is as follows: according to mass percentage, 0.04-0.06% of C, 15-16% of Cr, 8-12% of Mn, 4-5% of Ni, 0.8-1.2% of Si, 1-2% of Mo, 0.01-0.02% of P, 0.03-0.08% of La, 0.001-0.004% of S, 0.0001-0.002% of B, and the rest is Fe and inevitable impurity elements.

[0016] More preferably, the curing agent is 650 polyamide.

[0017] Compared with the prior art, the present application has the following beneficial effects:

[0018] (1) The present application provides a preparation method of a stainless steel pipe, the main components of the stainless steel pipe are C, Cr, Mn, Ni, Si, Mo, P, La, S, B and Fe, 1-2% of Mo is additionally added in the stainless steel pipe of the present application, the Mo enhances the corrosion resistance of the stainless steel pipe; the addition of 0.04-0.06% of C enhances the high pressure resistance of the stainless steel pipe.

[0019] (2)Secondly, the anti-corrosion paint with a thickness of 10 microns is coated on the polished and cleaned stainless steel pipe, so that the corrosion resistance of the stainless steel pipe is further enhanced.

[0020] The glass flake is a kind of flaky material, and has good chemical resistance, can change the structure of the coating, prolong the path of the corrosion medium to the surface of the stainless steel pipe, and improve the corrosion resistance of the anti-corrosion paint, but the glass flake is easy to agglomerate, and the glass flake is compounded with the silicon dioxide in the application, so that the dispersion performance is enhanced. The glass flake is modified by using trimethylolpropane tris (3-mercaptopropionate), so that the glass flake has mercapto groups, and the mercapto groups on the glass flake can react with the isocyanate groups on the modified silicon dioxide through click reaction, so that the two are compounded together, the dispersion of the glass flake in the anti-corrosion paint is improved, and the corrosion resistance of the stainless steel pipe is enhanced. Then, by adding methyltrimethoxysilane and hexadecyltrimethoxysilane, the hydrophobicity of the anti-corrosion composite additive is enhanced, so that the corrosion resistance is further enhanced.

[0021] The application also modifies the silicon dioxide by adding hexamethylene diisocyanate, grafts the isocyanate groups with high reactivity on the silicon dioxide, improves the dispersion of the silicon dioxide in the resin, and enhances the corrosion resistance. DETAILED DESCRIPTION

[0022] The technical solutions in the embodiments of the application will be clearly and completely described below. Obviously, the described embodiments are only part of the embodiments of the application, not all the embodiments. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor belong to the protection scope of the application.

[0023] There is no special restriction on the purchase manufacturer of all raw materials involved in the application, and exemplary ones include: nano-silicon dioxide, 20-100 nm; glass flake: thickness 5-10 microns; epoxy resin: model E-44, which can be purchased from Shanghai Maikelin; curing agent: 650 polyamide, which can be purchased from Jinan Qingtian Chemical Technology Co., Ltd.; defoaming agent: defoaming agent BX-825, which can be purchased from Shanghai Boyihe Chemical Co., Ltd.

[0024] Embodiment 1: A preparation method of a corrosion-resistant and high-pressure-resistant stainless steel pipe for marine engineering, comprising the following steps:

[0025] Step one: preparation of modified silicon dioxide:

[0026] Take 3g nanometer silicon dioxide, 100mL anhydrous xylene, 0.1g dimethyltin dilaurate, stir for 60min, get silica mixture; take 2g hexamethylene diisocyanate, 300mL anhydrous xylene, stir evenly, under nitrogen protection, add silica mixture, warm up to 90℃, react for 5h, wash, dry, get modified silica;

[0027] Step two: preparation of hydrophobic glass flake:

[0028] Take 2g glass flake, 50mL acetonitrile, ultrasonic dispersion, add 2g trimethylolpropane tris(3-mercaptopropionate), stir for 3.5h, dry, get modified glass flake;

[0029] Take 2g modified glass flake, 50mL anhydrous ethanol, ultrasonic dispersion, add 2g methyltrimethoxysilane, 4.5g hexadecyltrimethoxysilane, 2g ammonia, stir for 50min, dry, get hydrophobic glass flake;

[0030] Step three: preparation of anticorrosion composite additive:

[0031] Take 2g hydrophobic glass flake, 3g modified silica, 50mL acetonitrile, 1g triethylamine, ultrasonic dispersion, react for 5.5h, filter, wash, dry, get anticorrosion composite additive;

[0032] The mass ratio of hydrophobic glass flake and modified silica is 2:3;

[0033] Step four: preparation of anticorrosion coating:

[0034] Take 100g epoxy resin, 50g curing agent 650 polyamide, 15g anticorrosion composite additive, 1g defoamer BX-825, stir evenly, stand for 15min, get anticorrosion coating;

[0035] Step five: preparation of corrosion-resistant high-pressure stainless steel pipe:

[0036] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, smelt at 1700℃, then warm up to 1880℃, refine for 2.5h, cast ingot, anneal at 1200℃, keep warm for 9h, forge, extrude, anneal, get stainless steel pipe;

[0037] The component raw material of the stainless steel pipe is: 0.05% of C, 15.5% of Cr, 10% of Mn, 4.5% of Ni, 1% of Si, 1.5% of Mo, 0.015% of P, 0.06% of La, 0.003% of S, 0.00015% of B, the rest is Fe and inevitable impurity elements;

[0038] Take the stainless steel pipe, polish the outer surface, then put it in the acetone solution for ultrasonic cleaning for 15 min, then put it in anhydrous ethanol for ultrasonic cleaning for 25 min, deionized water ultrasonic cleaning for 25 min, vacuum drying, get the pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with a thickness of 15 μm of anticorrosive paint, then solidify at 27℃ for 22h, get the corrosion-resistant high-pressure stainless steel pipe.

[0039] Example 2: A method for preparing a corrosion-resistant high-pressure stainless steel pipe for ocean engineering, comprising the following steps:

[0040] Step one: preparation of modified silica:

[0041] Take 3g of nano-silica, 100mL of anhydrous xylene, 0.1g of dimethyltin dilaurate, stir for 50min, get silica mixture; take 2g of hexamethylene diisocyanate, 300mL of anhydrous xylene, stir evenly, add silica mixture under nitrogen protection, heat to 85℃, react for 4h, wash and dry to get modified silica;

[0042] Step two: preparation of hydrophobic glass flake:

[0043] Take 2g of glass flake, 50mL of acetonitrile, ultrasonic dispersion, add 2g of trimethylolpropane tris(3-mercaptopropionate), stir for 3h, dry to get modified glass flake;

[0044] Take 2g of modified glass flake, 50mL of anhydrous ethanol, ultrasonic dispersion, add 2g of methyltrimethoxysilane, 4.5g of hexadecyltrimethoxysilane, 2g of ammonia, stir for 40min, dry to get hydrophobic glass flake;

[0045] Step three: preparation of anticorrosive composite additive:

[0046] Take 2g of hydrophobic glass flake, 2.5g of modified silica, 50mL of acetonitrile, 1g of triethylamine, ultrasonic dispersion, react for 5-6h, filter, wash, dry to get anticorrosive composite additive;

[0047] The mass ratio of hydrophobic glass flake and modified silica is 2:2.5;

[0048] Step four: preparation of anticorrosive paint:

[0049] Take 100g of epoxy resin, 50g of curing agent 650 polyamide, 15g of anticorrosive composite additive, 1g of defoamer BX-825, stir evenly, stand for 10min, get anticorrosive paint;

[0050] Step five: preparation of corrosion-resistant high-pressure stainless steel pipe:

[0051] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, smelt at 1600 DEG C, then heat to 1850 DEG C, refine 2h, cast ingot, anneal at 1100 DEG C, heat preservation 8h, forge, extrude, anneal, get stainless steel pipe;

[0052] The component raw materials of the stainless steel pipe are: 0.04% of C, 15% of Cr, 8% of Mn, 4% of Ni, 0.8% of Si, 1% of Mo, 0.01% of P, 0.03% of La, 0.001% of S, 0.0001% of B, and the rest is Fe and inevitable impurity elements;

[0053] Take the stainless steel pipe, polish the outer surface, then place it in an acetone solution for ultrasonic cleaning for 10 minutes, then place it in anhydrous ethanol for ultrasonic cleaning for 20 minutes, and then deionized water for ultrasonic cleaning for 20 minutes, and then vacuum drying to obtain a pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat a corrosion-resistant coating with a thickness of 10 microns on the surface, and then solidify at 25 DEG C for 20 hours to obtain a corrosion-resistant and high-pressure-resistant stainless steel pipe.

[0054] Embodiment 3: A preparation method of a corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering, comprising the following steps:

[0055] Step one: preparation of modified silicon dioxide:

[0056] Take 3g of nano-silicon dioxide, 100mL of anhydrous xylene, and 0.1g of dimethyltin dilaurate, and stir for 70 minutes to obtain a silicon dioxide mixture; take 2g of hexamethylene diisocyanate and 300mL of anhydrous xylene, stir uniformly, and then add the silicon dioxide mixture under nitrogen protection, heat to 95 DEG C, and react for 6 hours, then wash and dry to obtain modified silicon dioxide;

[0057] Step two: preparation of hydrophobic glass flake:

[0058] Take 2g of glass flake and 50mL of acetonitrile, ultrasonic dispersion, add 2g of trimethylolpropane tris(3-mercaptopropionate), stir for 4 hours, and dry to obtain modified glass flake;

[0059] Take 2g of modified glass flake and 50mL of anhydrous ethanol, ultrasonic dispersion, add 2g of methyltrimethoxysilane, 4.5g of hexadecyltrimethoxysilane, and 2g of ammonia water, stir for 60 minutes, and dry to obtain hydrophobic glass flake;

[0060] Step three: preparation of corrosion-resistant composite additive:

[0061] Take 2g of hydrophobic glass flake, 4g of modified silicon dioxide, 50mL of acetonitrile, and 1g of triethylamine, ultrasonic dispersion, react for 6 hours, filter, wash, and dry to obtain a corrosion-resistant composite additive;

[0062] The mass ratio of the hydrophobic glass flake and the modified silicon dioxide is 2:4;

[0063] Step four: preparation of the anticorrosive coating:

[0064] Take 100 g of epoxy resin, 50 g of curing agent 650 polyamide, 15 g of anticorrosive composite additive, 1 g of defoaming agent BX-825, stir uniformly, stand for 20 min, and obtain the anticorrosive coating;

[0065] Step five: preparation of the corrosion-resistant and high-pressure-resistant stainless steel pipe:

[0066] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, and Fe, smelt at 1800℃, then heat to 1900℃, refine for 3h, cast ingot, anneal at 1300℃, keep warm for 10h, forge, extrude, and anneal, and obtain the stainless steel pipe;

[0067] The component raw materials of the stainless steel pipe are: 0.06% of C, 16% of Cr, 12% of Mn, 5% of Ni, 1.2% of Si, 2% of Mo, 0.02% of P, 0.08% of La, 0.004% of S, 0.002% of B, and the rest is Fe and inevitable impurity elements;

[0068] Take the stainless steel pipe, polish the outer surface, then place it in an acetone solution for ultrasonic cleaning for 20 min, then place it in anhydrous ethanol for ultrasonic cleaning for 30 min, then deionized water ultrasonic cleaning for 30 min, and vacuum drying, and obtain the pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with an anticorrosive coating with a thickness of 10μm, then solidify at 30℃ for 24h, and obtain the corrosion-resistant and high-pressure-resistant stainless steel pipe.

[0069] Comparative example 1: do not add hexamethylene diisocyanate to modify the silicon dioxide, and the rest is the same as example 1:

[0070] Step one: preparation of the hydrophobic glass flake:

[0071] Take 2g of glass flake and 50mL of acetonitrile, ultrasonic dispersion, add 2g of trimethylolpropane tris(3-mercaptopropionate), stir for 3.5h, and dry to obtain modified glass flake;

[0072] Take 2g of modified glass flake and 50mL of anhydrous ethanol, ultrasonic dispersion, add 2g of methyltrimethoxysilane, 4.5g of hexadecyltrimethoxysilane, and 2g of ammonia water, stir for 50min, and dry to obtain the hydrophobic glass flake;

[0073] Step two: preparation of the anticorrosive composite additive:

[0074] Take 2 g hydrophobic glass flake, 3 g nano silicon dioxide, 50 mL acetonitrile, 1 g triethylamine, ultrasonic dispersion, reaction for 5.5 h, filtration, washing, drying, to get the corrosion resistant composite additive;

[0075] The mass ratio of hydrophobic glass flake and nano silicon dioxide is 2:3;

[0076] Step three: preparation of anticorrosive paint:

[0077] Take 100 g epoxy resin, 50 g curing agent 650 polyamide, 15 g anticorrosive composite additive, 1 g defoamer BX-825, stir evenly, stand for 15 min, get anticorrosive paint;

[0078] Step four: preparation of corrosion resistant high pressure stainless steel pipe:

[0079] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, smelt at 1700℃, then heat to 1880℃, refine for 2.5 h, cast ingot, anneal at 1200℃, keep warm for 9 h, forge, extrude, anneal, get stainless steel pipe;

[0080] The component raw material of the stainless steel pipe is: 0.05% of C, 15.5% of Cr, 10% of Mn, 4.5% of Ni, 1% of Si, 1.5% of Mo, 0.015% of P, 0.06% of La, 0.003% of S, 0.00015% of B, the rest is Fe and inevitable impurity elements;

[0081] Take the stainless steel pipe, polish the outer surface, then ultrasonic cleaning in acetone solution for 15 min, ultrasonic cleaning in anhydrous ethanol for 25 min, deionized water ultrasonic cleaning for 25 min, vacuum drying, get pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with anticorrosive paint with a thickness of 15 μm, then cure at 27℃ for 22 h, get corrosion resistant high pressure stainless steel pipe.

[0082] Comparative example 2: no addition of hexadecyl trimethoxysilane, the rest is the same as example 1:

[0083] Step one: preparation of modified silicon dioxide:

[0084] Take 3 g nano silicon dioxide, 100 mL anhydrous xylene, 0.1 g dimethyl tin dilaurate, stir for 60 min, get silicon dioxide mixture; take 2 g hexamethylene diisocyanate, 300 mL anhydrous xylene, stir evenly, add silicon dioxide mixture under nitrogen protection, heat to 90℃, react for 5 h, wash, dry, get modified silicon dioxide;

[0085] Step two: preparation of hydrophobic glass flake:

[0086] Take 2 g glass flake, 50 mL acetonitrile, ultrasonic dispersion, add 2 g trimethylolpropane tris (3-mercaptopropionate), stirring 3.5 h, drying, to obtain modified glass flake;

[0087] Take 2 g modified glass flake, 50 mL anhydrous ethanol, ultrasonic dispersion, add 2 g methyltrimethoxysilane, 2 g ammonia, stirring 50 min, drying, to obtain hydrophobic glass flake;

[0088] Step three: preparation of corrosion-resistant composite additive:

[0089] Take 2 g hydrophobic glass flake, 3 g modified silica, 50 mL acetonitrile, 1 g triethylamine, ultrasonic dispersion, reaction 5.5 h, filtration, washing, drying, to obtain corrosion-resistant composite additive;

[0090] The mass ratio of hydrophobic glass flake and modified silica is 2:3;

[0091] Step four: preparation of corrosion-resistant paint:

[0092] Take 100 g epoxy resin, 50 g curing agent 650 polyamide, 15 g corrosion-resistant composite additive, 1 g defoamer BX-825, stirring uniformly, standing for 15 min, to obtain corrosion-resistant paint;

[0093] Step five: preparation of corrosion-resistant and high-pressure-resistant stainless steel pipe:

[0094] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, melt at 1700℃, then heat to 1880℃, refine for 2.5 h, cast ingot, anneal at 1200℃, heat preservation for 9 h, forge, extrude, anneal, to obtain stainless steel pipe;

[0095] The component raw materials of the stainless steel pipe are: 0.05% of C, 15.5% of Cr, 10% of Mn, 4.5% of Ni, 1% of Si, 1.5% of Mo, 0.015% of P, 0.06% of La, 0.003% of S, 0.00015% of B, and the rest is Fe and inevitable impurity elements;

[0096] Take the stainless steel pipe, polish the outer surface, then ultrasonic cleaning in acetone solution for 15 min, ultrasonic cleaning in anhydrous ethanol for 25 min, deionized water ultrasonic cleaning for 25 min, vacuum drying, to obtain pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with corrosion-resistant paint with a thickness of 15 μm, then cure at 27℃ for 22 h, to obtain corrosion-resistant and high-pressure-resistant stainless steel pipe.

[0097] Comparative Example 3: The mass ratio of hydrophobic glass flake and modified silica is 2:2, and the rest is the same as Example 1:

[0098] Step one: Preparation of modified silica:

[0099] Take 3g nanosilica, 100mL anhydrous xylene, 0.1g dimethyltin dilaurate, stir for 60min to obtain a silica mixture; take 2g hexamethylene diisocyanate, 300mL anhydrous xylene, stir evenly, add the silica mixture under nitrogen protection, warm up to 90℃, react for 5h, wash and dry to obtain modified silica;

[0100] Step two: Preparation of hydrophobic glass flake:

[0101] Take 2g glass flake, 50mL acetonitrile, ultrasonic dispersion, add 2g trimethylolpropane tris(3-mercaptopropionate), stir for 3.5h, dry to obtain modified glass flake;

[0102] Take 2g modified glass flake, 50mL anhydrous ethanol, ultrasonic dispersion, add 2g methyltrimethoxysilane, 4.5g hexadecyltrimethoxysilane, 2g ammonia, stir for 50min, dry to obtain hydrophobic glass flake;

[0103] Step three: Preparation of anticorrosive composite additive:

[0104] Take 2g hydrophobic glass flake, 2g modified silica, 50mL acetonitrile, 1g triethylamine, ultrasonic dispersion, react for 5.5h, filter, wash, dry to obtain anticorrosive composite additive;

[0105] The mass ratio of hydrophobic glass flake and modified silica is 2:2;

[0106] Step four: Preparation of anticorrosive coating:

[0107] Take 100g epoxy resin, 50g curing agent 650 polyamide, 15g anticorrosive composite additive, 1g defoamer BX-825, stir evenly, stand for 15min to obtain anticorrosive coating;

[0108] Step five: Preparation of corrosion-resistant and high-pressure-resistant stainless steel pipe:

[0109] Take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, melt at 1700℃, then warm up to 1880℃, refine for 2.5h, cast ingot, anneal at 1200℃, keep warm for 9h, forge, extrude, anneal to obtain stainless steel pipe;

[0110] The component raw materials of the stainless steel pipe are as follows in terms of mass percentage: 0.05% of C, 15.5% of Cr, 10% of Mn, 4.5% of Ni, 1% of Si, 1.5% of Mo, 0.015% of P, 0.06% of La, 0.003% of S, 0.00015% of B, and the rest of Fe and inevitable impurity elements;

[0111] The stainless steel pipe is polished and then placed in an acetone solution for ultrasonic cleaning for 15 min, placed in anhydrous ethanol for ultrasonic cleaning for 25 min, and placed in deionized water for ultrasonic cleaning for 25 min, and then vacuum dried to obtain a pretreated stainless steel pipe. The pretreated stainless steel pipe is coated with a corrosion-resistant paint with a thickness of 15 μm, and then cured at 27℃ for 22 h to obtain a corrosion-resistant and high-pressure-resistant stainless steel pipe.

[0112] Experiment:

[0113] The stainless steel pipes prepared in Examples 1-3 and Comparative Examples 1-3 are subjected to performance testing. A scratch with a length of 50 mm is made on the surface of the stainless steel pipe, and the scratch is made to expose the stainless steel pipe substrate. A salt spray test is performed according to GB / T1771-2007, and the time of corrosion occurrence is recorded. The data obtained are shown in the following table:

[0114]

[0115] Conclusion: In Comparative Example 1, the silica is not modified by hexamethylene diisocyanate, the glass flake cannot be compounded with the silica, the dispersibility is poor, the corrosion resistance is poor, and the adhesion of the paint is decreased. In Comparative Example 2, the hydrophobicity is poor due to the absence of hexadecyltrimethoxysilane, and the corrosion resistance of the stainless steel pipe is poor. In Comparative Example 3, the mass ratio of the hydrophobic glass flake and the modified silica is 2:2, the amount of silica added is small, and the amount of silica compounded on the glass flake is small, so the corrosion resistance is poor. In Examples 1-3 of the present application, the glass flake is modified by trimethylolpropane tris(3-mercaptopropionate), so that the glass flake has mercapto groups, and the mercapto groups on the glass flake can undergo a click reaction with the isocyanate groups on the modified silica, so that the two are compounded together, the dispersibility of the glass flake in the corrosion-resistant paint is improved, and the corrosion resistance of the stainless steel pipe is best.

[0116] Finally, it should be noted that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Although the present 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 replacements to some technical features. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application shall be included in the protection scope of the present application.

Claims

1. A method for producing a corrosion-resistant high-pressure stainless steel pipe for ocean engineering, characterized by: It comprises the following steps: Step one: take hydrophobic glass flake, modified silica, acetonitrile, triethylamine, ultrasonic dispersion, reaction for 5-6h, filtration, washing, drying, to get the anticorrosive composite additive; Step two: take epoxy resin, curing agent, anticorrosive composite additive, defoaming agent, stirring evenly, standing for 10-20min, to get the anticorrosive coating; Step three: take stainless steel pipe, polish the outer surface, clean, vacuum drying, to get the pretreated stainless steel pipe; take the pretreated stainless steel pipe, coat the surface with anticorrosive coating, then cure at 25-30℃ for 20-24h, to get the corrosion-resistant and high-pressure-resistant stainless steel pipe; The preparation method of the hydrophobic glass flake is: take modified glass flake, anhydrous ethanol, ultrasonic dispersion, add methyltrimethoxysilane, hexadecyltrimethoxysilane, ammonia, stirring for 40-60min, drying, to get the hydrophobic glass flake; The preparation method of the modified glass flake is: take glass flake, acetonitrile, ultrasonic dispersion, add trimethylolpropane tris(3-mercaptopropionate), stirring for 3-4h, drying, to get the modified glass flake; The preparation method of the modified silica is: take nano-silica, anhydrous xylene, dimethyltin dilaurylate, stirring for 50-70min, to get the silica mixed solution; take hexamethylene diisocyanate, anhydrous xylene, stirring evenly, add the silica mixed solution under nitrogen protection, heat to 85-95℃, reaction for 4-6h, washing, drying, to get the modified silica; The mass ratio of the hydrophobic glass flake and the modified silica is 2:(2.5-4).

2. The method of claim 1, wherein the method is characterized by: In step three, the preparation method of the stainless steel pipe is: take C, Cr, Mn, Ni, Si, Mo, P, La, S, B, Fe, smelt at 1600-1800℃, then heat to 1850-1900℃, refine for 2-3h, cast ingot, anneal at 1100-1300℃, heat preservation for 8-10h, forge, extrude, anneal, to get the stainless steel pipe.

3. The method of claim 2, wherein the method comprises the steps of: providing a stainless steel tube; and subjecting the stainless steel tube to a process of cold working and a process of heat treatment. The component raw material of the stainless steel pipe is: according to mass percentage, 0.04-0.06% of C, 15-16% of Cr, 8-12% of Mn, 4-5% of Ni, 0.8-1.2% of Si, 1-2% of Mo, 0.01-0.02% of P, 0.03-0.08% of La, 0.001-0.004% of S, 0.0001-0.002% of B, the rest is Fe and inevitable impurity elements.

4. The method of claim 1, wherein the method is characterized by: The curing agent is 650 polyamide.

5. A kind of corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering prepared by the preparation method of a kind of corrosion-resistant and high-pressure-resistant stainless steel pipe for ocean engineering according to any one of claims 1-4.

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