A method for preventing corrosion of high-pressure seamless steel pipe

Abstract

The invention discloses a high-pressure seamless steel pipe anti-corrosion method, which relates to the technical field of steel pipe anti-corrosion. The method comprises the following steps: alkali washing and pickling are performed to remove oil stains and oxides on the surface of the steel pipe; a plating-assisting solution is added to form a passivation film on the surface of the steel pipe, thereby increasing the wettability of the steel pipe; the steel pipe is dried before immersion plating to remove residual moisture on the surface of the steel pipe, thereby avoiding splashing of zinc liquid when adding immersion liquid, and achieving high safety; finally, a push plate is driven by a push rod to move along the length direction of the steel pipe, thereby evenly distributing the zinc liquid inside the steel pipe and forming a coating, thereby avoiding accumulation of zinc liquid somewhere inside the steel pipe, thereby avoiding large differences in coating thickness, and possibly causing errors during detection.

Description

Technical Field

[0001] The present invention relates to the technical field of steel pipe anti-corrosion, and in particular to a high-pressure seamless steel pipe anti-corrosion method. Background Art

[0002] As we all know, steel materials have a wide range of uses, but their corrosion resistance is relatively poor. The corrosion of steel will prevent many steel resources from being better utilized and will also cause great pollution to the environment. A large number of products made of steel as raw materials are discarded because they cannot withstand long-term acid and alkali corrosion. It is not only a waste of resources. Due to the substandard quality of steel products, safety accidents have occurred repeatedly in some enterprises, affecting the personal safety of workers and the development of enterprises. For steel pipes used in underground emulsion conveying pipelines in coal mines, the inner wall surface is required to be more fully electroplated, but the traditional galvanizing process has poor fluidity of zinc liquid on the inner wall surface, so the galvanizing effect of the inner wall surface is not ideal, which seriously restricts the application of steel pipes. Summary of the Invention

[0003] The technical problem to be solved by the present invention is: to address the deficiencies in the prior art and to provide a high-pressure seamless steel pipe anti-corrosion method, which has good galvanizing effect on the inner wall of the pipe and strong anti-corrosion performance.

[0004] In order to solve the above technical problems, the technical solution of the present invention is:

[0005] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0006] Alkaline washing and degreasing

[0007] Immerse the high-pressure seamless steel pipe in alkali solution for 5 to 10 minutes to wash away the oil stains on the surface of the steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water 2 to 3 times;

[0008] Pickling and rust removal

[0009] Immerse the high-pressure seamless steel pipe in a hydrochloric acid solution for 5 to 10 minutes to remove the oxide on the surface of the high-pressure seamless steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water 2 to 3 times;

[0010] Solution flux plating

[0011] Immerse the high-pressure seamless steel pipe in the flux solution for 2 to 3 minutes to form a passivation film on the surface of the high-pressure seamless steel pipe and increase the wettability of the high-pressure seamless steel pipe;

[0012] drying

[0013] Dry the high-pressure seamless steel pipe to remove residual moisture on the surface of the high-pressure seamless steel pipe;

[0014] Hot-dip galvanizing

[0015] The galvanizing tank is filled with immersion liquid, and the two ends of the high-pressure seamless steel pipe are respectively placed on the fixed teeth on the outer side of the rotating wheel. The rotating wheel is driven by the rotating shaft to rotate so that the high-pressure seamless steel pipe moves circumferentially along the rotating shaft. A zinc liquid pushing rod is set at the entrance of one end of the steel pipe. One end of the zinc liquid pushing rod is provided with a pushing plate, and the other end of the zinc liquid pushing rod is provided with a driving device. Each steel pipe stays in the immersion liquid for 4 to 6 minutes, and the pushing plate is reciprocated on the inner side of the high-pressure seamless steel pipe 2 to 3 times to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe.

[0016] Treatment of residual zinc solution

[0017] The high-pressure seamless steel pipe is tilted to allow excess zinc liquid in the pipe to flow out.

[0018] Preferably, a corrosion inhibitor is added to the hydrochloric acid solution, wherein the corrosion inhibitor is one of chromate, molybdate, vanadate and borate, and the weight of the corrosion inhibitor added accounts for 0.5% to 0.8% of the weight of the hydrochloric acid solution.

[0019] Preferably, the pH value of the alkali solution in the alkaline degreasing process is 12 to 13, and the pH value of the hydrochloric acid solution in the pickling and rust removal process is 0.5 to 1.

[0020] Preferably, the temperature of the flux-plating solution in the solution flux-plating is 70-80°C.

[0021] Preferably, the plating-boosting solution contains zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the plating-boosting solution is 530-560 g, and the content of ammonium chloride in each liter of the plating-boosting solution is 90-110 g.

[0022] Preferably, the temperature during drying is controlled at 95-108° C., and the drying time is 6-8 minutes.

[0023] Preferably, the temperature of the galvanizing bath in hot-dip galvanizing is 430-460°C.

[0024] Preferably, the push plate is provided with a plurality of openings along the circumferential direction.

[0025] Preferably, the distance between the outer edge of the push plate and the inner wall of the steel pipe is 0.2 to 0.5 mm.

[0026] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0027] 1. Through alkaline washing and pickling, the oil and oxide on the surface of the steel pipe are removed, and the zinc liquid can better contact and adhere to the steel pipe. The formed coating is more stable and not easy to separate from the steel pipe.

[0028] 2. By adding the plating solution, a passivation film is formed on the surface of the steel pipe, which increases the wettability of the steel pipe and facilitates subsequent immersion plating. The zinc solution can better adhere to the surface of the steel pipe.

[0029] 3. Dry the steel pipe before dipping to remove residual moisture on the surface of the steel pipe to avoid splashing of zinc liquid when adding dipping solution. It is safer and the formed coating is more uniform.

[0030] 4. By driving the push plate along the length of the steel pipe through the push rod, the zinc liquid can be evenly distributed inside the steel pipe to form a coating, avoiding the accumulation of zinc liquid somewhere inside the steel pipe, resulting in large differences in coating thickness, which may lead to errors during detection.

[0031] 5. The setting of the opening reduces the resistance of the push plate when it moves. At the same time, the push plate forms a pressure difference before and after the opening, which plays a turbulent role and increases the mixing of the zinc liquid before and after the opening, making the coating on the inside of the steel pipe more uniform.

[0032] 6. By adding corrosion inhibitors, the plasticity and toughness of the steel pipe are increased, and the corrosion of the hydrochloric acid solution on the steel pipe surface is slowed down. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 is a perspective view of an embodiment of the present invention;

[0034] Figure 2 is a front view of an embodiment of the present invention;

[0035] Figure 3 It is a left side view of an embodiment of the present invention;

[0036] Figure 4 yes Figure 1 Schematic diagram of the structure of the middle push plate;

[0037] Among them: 1. Rotor; 2. Fixed gear; 3. Rotating shaft; 4. Zinc liquid push rod; 5. Push plate; 6. Opening; 7. High-pressure seamless steel pipe. DETAILED DESCRIPTION

[0038] The present invention will be further described below with reference to the embodiments.

[0039] Example 1

[0040] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0041] Alkaline washing and degreasing

[0042] The high-pressure seamless steel pipe is immersed in alkaline solution for 5 minutes. The pH value of the alkaline solution is 12. The oil stains on the surface of the steel pipe are washed off. After taking it out, rinse the surface and inside of the steel pipe with clean water twice;

[0043] Pickling and rust removal

[0044] The high-pressure seamless steel pipe is immersed in a hydrochloric acid solution for 5 minutes. The pH value of the hydrochloric acid solution is 1. The oxide on the surface of the high-pressure seamless steel pipe is removed. After being fished out, the surface and inside of the steel pipe are rinsed twice with clean water. A corrosion inhibitor is added to the hydrochloric acid solution. The corrosion inhibitor is sodium chromate, and the weight of the corrosion inhibitor added accounts for 0.5% of the weight of the hydrochloric acid solution.

[0045] Solution flux plating

[0046] Immerse the high-pressure seamless steel pipe in a flux solution for 2 minutes. The flux solution is an aqueous solution of zinc chloride and ammonium chloride, with 530g of zinc chloride and 90g of ammonium chloride per liter of flux solution. The flux solution is heated to 70°C to form a passivation film on the surface of the high-pressure seamless steel pipe, thereby increasing its wettability.

[0047] drying

[0048] The high-pressure seamless steel pipe is dried to remove residual moisture on the surface of the high-pressure seamless steel pipe. The temperature is controlled at 95°C during drying and the drying time is 6 minutes.

[0049] Hot-dip galvanizing

[0050] The galvanizing tank is filled with immersion liquid, and the temperature of the immersion liquid is 430°C. The two ends of the high-pressure seamless steel pipe 7 are respectively placed on the fixed teeth 2 on the outside of the runner 1, and the runner 1 is driven to rotate by the rotating shaft 3 to realize the circumferential movement of the high-pressure seamless steel pipe 7 along the rotating shaft 3. A zinc liquid push rod 4 is arranged at the entrance of one end of the high-pressure seamless steel pipe 7, and a push plate 5 is arranged at one end of the zinc liquid push rod 4. The other end of the zinc liquid push rod 4 is provided with a driving device. The driving device in this embodiment can be a stepping motor. Each steel pipe 7 stays in the immersion liquid for 4 minutes, and the push plate 5 is used to reciprocate twice on the inner side of the high-pressure seamless steel pipe 7 to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe 7. The push plate 5 is provided with a number of openings 6 along the circumferential direction, and the distance between the outer edge of the push plate 5 and the inner wall of the steel pipe 7 is 0.2 mm.

[0051] Treatment of residual zinc solution

[0052] The high-pressure seamless steel pipe 7 is tilted to allow excess zinc liquid in the pipe to flow out, thereby obtaining a corrosion-resistant high-pressure seamless steel pipe.

[0053] Example 2

[0054] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0055] Alkaline washing and degreasing

[0056] The high-pressure seamless steel pipe is immersed in alkaline solution for 7 minutes. The pH value of the alkaline solution is 12. The oil stains on the surface of the steel pipe are washed off. After taking it out, rinse the surface and inside of the steel pipe with clean water twice;

[0057] Pickling and rust removal

[0058] The high-pressure seamless steel pipe is immersed in a hydrochloric acid solution for 7 minutes. The pH value of the hydrochloric acid solution is 0.8. The oxide on the surface of the high-pressure seamless steel pipe is removed. After being fished out, the surface and inside of the steel pipe are rinsed twice with clean water; a corrosion inhibitor is added to the hydrochloric acid solution. The corrosion inhibitor is sodium molybdate, and the weight of the corrosion inhibitor added accounts for 0.6% of the weight of the hydrochloric acid solution.

[0059] Solution flux plating

[0060] The high-pressure seamless steel pipe is placed in a plating flux solution and immersed for 2 minutes. The temperature of the plating flux solution is 73°C, so that a passivation film is formed on the surface of the high-pressure seamless steel pipe, thereby increasing the wettability of the high-pressure seamless steel pipe. The plating flux solution is an aqueous solution of zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the plating flux solution is 540g, and the content of ammonium chloride in each liter of the plating flux solution is 98g.

[0061] drying

[0062] The high-pressure seamless steel pipe is dried to remove residual moisture on the surface of the high-pressure seamless steel pipe. The temperature during drying is controlled at 98°C and the drying time is 6 minutes.

[0063] Hot-dip galvanizing

[0064] The galvanizing tank is filled with immersion liquid, and the temperature of the immersion liquid is 440°C. The two ends of the high-pressure seamless steel pipe 7 are respectively placed on the fixed teeth 2 on the outside of the runner 1, and the runner 1 is driven to rotate by the rotating shaft 3 to realize the circumferential movement of the high-pressure seamless steel pipe 7 along the rotating shaft 3. A zinc liquid push rod 4 is set at the entrance of one end of the high-pressure seamless steel pipe 7, and a push plate 5 is provided at one end of the zinc liquid push rod 4. The other end of the zinc liquid push rod 4 is provided with a driving device. The driving device in this embodiment can be a stepping motor. Each steel pipe stays in the immersion liquid for 4 minutes, and the push plate 5 is used to reciprocate twice on the inner side of the high-pressure seamless steel pipe 7 to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe 7; the push plate 5 is provided with a number of openings 6 along the circumference, and the distance between the outer edge of the push plate 5 and the inner wall of the steel pipe is 0.25mm.

[0065] Treatment of residual zinc solution

[0066] The high-pressure seamless steel pipe 7 is tilted to allow excess zinc liquid in the pipe to flow out, thereby obtaining a corrosion-resistant high-pressure seamless steel pipe.

[0067] Example 3

[0068] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0069] Alkaline washing and degreasing

[0070] The high-pressure seamless steel pipe is immersed in alkaline solution for 8 minutes. The pH value of the alkaline solution is 13. The oil stains on the surface of the steel pipe are washed off. After being fished out, the surface and inside of the steel pipe are rinsed with clean water for 3 times.

[0071] Pickling and rust removal

[0072] The high-pressure seamless steel pipe is immersed in a hydrochloric acid solution with a pH value of 0.6 for 8 minutes to remove the oxide on the surface of the high-pressure seamless steel pipe. After being fished out, the surface and inside of the steel pipe are rinsed 3 times with clean water; a corrosion inhibitor is added to the hydrochloric acid solution, and the corrosion inhibitor is ammonium vanadate. The weight of the corrosion inhibitor added accounts for 0.7% of the weight of the hydrochloric acid solution.

[0073] Solution flux plating

[0074] The high-pressure seamless steel pipe is placed in a plating flux solution and immersed for 3 minutes. The temperature of the plating flux solution is 78°C, so that a passivation film is formed on the surface of the high-pressure seamless steel pipe, thereby increasing the wettability of the high-pressure seamless steel pipe. The plating flux solution is an aqueous solution of zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the plating flux solution is 550g, and the content of ammonium chloride in each liter of the plating flux solution is 105g.

[0075] drying

[0076] The high-pressure seamless steel pipe is dried to remove residual moisture on the surface of the high-pressure seamless steel pipe. The temperature during drying is controlled at 103°C and the drying time is 7 minutes.

[0077] Hot-dip galvanizing

[0078] The galvanizing tank is filled with immersion liquid, and the temperature of the immersion liquid is 450 ℃. The two ends of the high-pressure seamless steel pipe 7 are respectively placed on the fixed teeth 2 on the outside of the runner 1, and the runner 1 is driven to rotate by the rotating shaft 3 to realize the circumferential movement of the high-pressure seamless steel pipe 7 along the rotating shaft 3. A zinc liquid push rod 4 is set at the entrance of one end of the high-pressure seamless steel pipe 7, and a push plate 5 is provided at one end of the zinc liquid push rod 4. The other end of the zinc liquid push rod 4 is provided with a driving device. Each steel pipe stays in the immersion liquid for 5 minutes, and the push plate 5 is used to reciprocate 3 times on the inner side of the high-pressure seamless steel pipe 7 to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe 7; the push plate 5 is provided with a number of openings 6 along the circumference, and the distance between the outer edge of the push plate 5 and the inner wall of the steel pipe is 0.4 mm.

[0079] Treatment of residual zinc solution

[0080] The high-pressure seamless steel pipe 7 is tilted to allow excess zinc liquid in the pipe to flow out, thereby obtaining a corrosion-resistant high-pressure seamless steel pipe.

[0081] Example 4

[0082] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0083] Alkaline washing and degreasing

[0084] Immerse the high-pressure seamless steel pipe in alkali solution for 10 minutes. The pH value of the alkali solution is 13. Wash away the oil stains on the surface of the steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water for 3 times.

[0085] Pickling and rust removal

[0086] The high-pressure seamless steel pipe is immersed in a hydrochloric acid solution with a pH value of 0.5 for 10 minutes to remove the oxide on the surface of the high-pressure seamless steel pipe. After being fished out, the surface and inside of the steel pipe are rinsed three times with clean water; a corrosion inhibitor is added to the hydrochloric acid solution, and the corrosion inhibitor is sodium borate. The weight of the corrosion inhibitor added accounts for 0.8% of the weight of the hydrochloric acid solution.

[0087] Solution flux plating

[0088] The high-pressure seamless steel pipe is placed in a plating flux solution and immersed for 3 minutes. The temperature of the plating flux solution is 80°C, so that a passivation film is formed on the surface of the high-pressure seamless steel pipe, thereby increasing the wettability of the high-pressure seamless steel pipe. The plating flux solution is an aqueous solution of zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the plating flux solution is 560g, and the content of ammonium chloride in each liter of the plating flux solution is 110g.

[0089] drying

[0090] The high-pressure seamless steel pipe is dried to remove residual moisture on the surface of the high-pressure seamless steel pipe. The drying temperature is controlled at 108°C and the drying time is 8 minutes.

[0091] Hot-dip galvanizing

[0092] The galvanizing tank is filled with immersion liquid, the temperature of the immersion liquid is 460 ℃, and the two ends of the high-pressure seamless steel pipe 7 are respectively placed on the fixed teeth 2 on the outside of the runner 1, and the runner 1 is driven to rotate by the rotating shaft 3 to realize the circumferential movement of the high-pressure seamless steel pipe 7 along the rotating shaft 3. A zinc liquid push rod 4 is set at the entrance of one end of the steel high-pressure seamless steel pipe 7, and a push plate 5 is provided at one end of the zinc liquid push rod 4. The other end of the zinc liquid push rod 4 is provided with a driving device. Each steel pipe stays in the immersion liquid for 6 minutes, and the push plate 5 is used to reciprocate 3 times on the inner side of the high-pressure seamless steel pipe 7 to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe 7; the push plate 5 is provided with a number of openings 6 along the circumference, and the distance between the outer edge of the push plate 5 and the inner wall of the steel pipe is 0.5 mm.

[0093] Treatment of residual zinc solution

[0094] The high-pressure seamless steel pipe 7 is tilted to allow excess zinc liquid in the pipe to flow out, thereby obtaining a corrosion-resistant high-pressure seamless steel pipe.

[0095] Comparative Example

[0096] A method for anti-corrosion of a high-pressure seamless steel pipe comprises the following steps:

[0097] Alkaline washing and degreasing

[0098] Immerse the high-pressure seamless steel pipe in alkali solution for 10 minutes. The pH value of the alkali solution is 13. Wash away the oil stains on the surface of the steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water for 3 times.

[0099] Pickling and rust removal

[0100] The high-pressure seamless steel pipe is immersed in a hydrochloric acid solution with a pH value of 0.5 for 10 minutes to remove the oxide on the surface of the high-pressure seamless steel pipe. After being fished out, the surface and inside of the steel pipe are rinsed three times with clean water; a corrosion inhibitor is added to the hydrochloric acid solution, and the corrosion inhibitor is sodium borate. The weight of the corrosion inhibitor added accounts for 0.8% of the weight of the hydrochloric acid solution.

[0101] Solution flux plating

[0102] The high-pressure seamless steel pipe is placed in a plating flux solution and immersed for 3 minutes. The temperature of the plating flux solution is 80°C, so that a passivation film is formed on the surface of the high-pressure seamless steel pipe, thereby increasing the wettability of the high-pressure seamless steel pipe. The plating flux solution is an aqueous solution of zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the plating flux solution is 560g, and the content of ammonium chloride in each liter of the plating flux solution is 110g.

[0103] drying

[0104] The high-pressure seamless steel pipe is dried to remove residual moisture on the surface of the high-pressure seamless steel pipe. The drying temperature is controlled at 108°C and the drying time is 8 minutes.

[0105] Hot-dip galvanizing

[0106] The galvanizing tank is filled with immersion solution at a temperature of 460°C. The two ends of the high-pressure seamless steel pipe are placed on the fixed teeth on the outside of the runner, and the runner is driven by the shaft to rotate to achieve the circumferential movement of the high-pressure seamless steel pipe along the shaft. Each steel pipe stays in the immersion solution for 6 minutes.

[0107] Treatment of residual zinc solution

[0108] The high-pressure seamless steel pipe is tilted to allow excess zinc liquid in the pipe to flow out, thereby obtaining a high-pressure seamless steel pipe.

[0109] The steel pipes prepared by Examples 1-4 and the comparative example were respectively subjected to the following tests under the same conditions: uniformity test of the galvanized layer (the steel pipe sample should not turn red after being immersed in the copper sulfate solution for 5 consecutive times), surface quality test (surface flatness, no bubbles), thickness test of the galvanized layer, and rust test after the steel pipe was placed for three months. The following results were obtained:

[0110]

[0111] It can be seen from the table that the pushing rod stirs the zinc liquid and the pushing plate redistributes the zinc liquid inside the steel pipe, so that the electroplating of the inner wall of the steel pipe is more sufficient, the coating is more uniform, the thickness consistency is good, and the anti-corrosion performance is stronger.

[0112] It should be understood that these embodiments are only used to illustrate the present invention and are not intended to limit the scope of the present invention. In addition, it should be understood that after reading the content taught by the present invention, those skilled in the art can make various changes or modifications to the present invention, and these equivalent forms also fall within the scope limited by the appended claims of the application.

Claims

1. A method for anti-corrosion of high-pressure seamless steel pipes, characterized in that The following steps are involved: Alkaline washing and degreasing Immerse the high-pressure seamless steel pipe in alkali solution for 5 to 10 minutes to wash away the oil stains on the surface of the steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water 2 to 3 times; Pickling and rust removal Immerse the high-pressure seamless steel pipe in a hydrochloric acid solution for 5 to 10 minutes to remove the oxide on the surface of the high-pressure seamless steel pipe. After taking it out, rinse the surface and inside of the steel pipe with clean water 2 to 3 times; Solution flux plating Immerse the high-pressure seamless steel pipe in the flux solution for 2 to 3 minutes to form a passivation film on the surface of the high-pressure seamless steel pipe and increase the wettability of the high-pressure seamless steel pipe; drying Dry the high-pressure seamless steel pipe to remove residual moisture on the surface of the high-pressure seamless steel pipe; Hot-dip galvanizing The galvanizing tank is filled with immersion liquid, and the two ends of the high-pressure seamless steel pipe are respectively placed on the fixed teeth on the outside of the rotating wheel. The rotating wheel is driven by the rotating shaft to rotate so that the high-pressure seamless steel pipe moves circumferentially along the rotating shaft. A zinc liquid push rod is set at the entrance of one end of the steel pipe, and a push plate is provided at one end of the zinc liquid push rod, and a driving device is provided at the other end of the zinc liquid push rod. Each steel pipe stays in the immersion liquid for 4 to 6 minutes, and the push plate is reciprocated on the inner side of the high-pressure seamless steel pipe 2 to 3 times to evenly apply the immersion liquid to the inner side of the high-pressure seamless steel pipe. The push plate is provided with a plurality of openings along the circumference, and the distance between the outer edge of the push plate and the inner wall of the steel pipe is 0.2 to 0.5 mm. Treatment of residual zinc solution The high-pressure seamless steel pipe is tilted to allow excess zinc liquid in the pipe to flow out.

2. A method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, characterized in that: A corrosion inhibitor is added to the hydrochloric acid solution. The corrosion inhibitor is one of chromate, molybdate, vanadate and borate. The weight of the corrosion inhibitor accounts for 0.5% to 0.8% of the weight of the hydrochloric acid solution.

3. A method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, characterized in that: The pH value of the alkali solution in alkaline degreasing is 12-13, and the pH value of the hydrochloric acid solution in pickling and rust removal is 0.5-1.

4. A method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, characterized in that: The temperature of the flux solution in the solution flux plating is 70-80°C.

5. The method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, wherein: The auxiliary plating solution contains zinc chloride and ammonium chloride, wherein the content of zinc chloride in each liter of the auxiliary plating solution is 530-560g, and the content of ammonium chloride in each liter of the auxiliary plating solution is 90-110g.

6. A method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, characterized in that: During drying, the temperature is controlled at 95-108°C and the drying time is 6-8 minutes.

7. A method for anti-corrosion of a high-pressure seamless steel pipe according to claim 1, characterized in that: The temperature of the galvanizing bath in hot dip galvanizing is 430-460°C.

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