A nickel-based corrosion-resistant injection-production pipe and its manufacturing method

Abstract

This invention discloses a nickel-based corrosion-resistant injection-production pipe containing Fe and unavoidable impurity elements. Its key feature is that it also contains the following chemical elements in the following mass percentages: 0 < C ≤ 0.03%, 0 < Si ≤ 0.5%, 0 < Mn ≤ 1.0%, Cr: 25-35%, Ni: 30-40%, Mo: 3-5%, Al: 0.1-1.0%, Cu: 0.1-1.0%, Nb: 0.01-0.1%. Correspondingly, this invention also discloses a method for manufacturing the nickel-based corrosion-resistant injection-production pipe, comprising the steps of: smelting and casting to obtain an ingot; forging the ingot into a pipe blank; heating the pipe blank; hot extrusion; solution treatment; aging treatment; and cold rolling. This nickel-based corrosion-resistant injection-production pipe exhibits resistance to corrosion in high-salt, high-pressure oxygen environments.

Description

Technical Field

[0001] This invention relates to a pipe and its manufacturing method, and more particularly to an injection / production pipe and its manufacturing method. Background Technology

[0002] Underground compressed air energy storage is characterized by high oxygen, high water, and high salinity. As the transmission channel for high-pressure air between the storage cavity and the surface, the injection and production pipes face severe oxygen corrosion and chloride ion erosion. Commonly used carbon steel injection and production pipes exhibit uniform corrosion rates of 2–10 mm / a due to oxygen corrosion in underground compressed air energy storage, which are tens or even hundreds of times higher than the corrosion rates of common acidic substances such as CO2 and H2S. Stainless steel injection and production pipes are prone to extremely severe localized corrosion due to chloride ion erosion. For example, the pitting corrosion rates of widely used 13Cr, 304, and 2507 stainless steels in underground compressed air energy storage can reach up to 62 mm / a, 42 mm / a, and 5 mm / a, respectively.

[0003] Based on this, the nickel-based alloy injection and production pipe currently under research aims to meet the corrosion resistance requirements of pipes used in underground compressed air energy storage applications.

[0004] For example, Chinese patent document CN101613834A, published on December 30, 2009, entitled "Fe-based austenitic alloy oil casing for high-acidity deep wells and its manufacturing method," discloses a method for manufacturing an iron-based austenitic alloy. Its chemical elemental composition (unless otherwise specified, all elemental compositions are by mass) is: C≤0.03%, P≤0.03%, S≤0.03%, Si 0.01~1.0%, Mn0.01~3.0%, Ni 25~40%, Cr 20~35%, Mo 1~5%, Cu 0.1~1.5%, Al 0.01~0.5%, O≤0.01%, with the balance being iron and unavoidable impurities. The oil casing is then hot-extruded and cold-rolled to obtain a 90~140ksi steel grade. The patent does not specify the Ni and Cr equivalents, which may lead to the formation of more δ-ferrite in the austenitic alloy, thereby compromising the overall corrosion resistance of the alloy and increasing the tendency of the alloy to crack during processing.

[0005] For example, Chinese patent document CN114472524A, published on May 13, 2022, entitled "A Method for Preparing an Iron-Nickel-Based Alloy Oil Well Pipe," discloses a method for manufacturing an iron-nickel-based alloy oil well pipe. Its chemical elemental composition is: C≤0.05%, Si≤0.5%, Mn≤1%, P≤0.03%, S≤0.03%, Al≤0.2%, Ti 0.6~1.2%, Cu 1.5~3%, Mo 2.5~3.5%, Cr 19.5~23.5%, Ni 38~46%, with the balance being iron and unavoidable impurities. The pipe is then hot-extruded and cold-rolled to obtain an oil well pipe with a yield strength of over 760 MPa. This patent uses a low Cr content design, primarily for use in acidic oil and gas wells with low oxygen content. However, it is prone to pitting corrosion in underground compressed air energy storage conditions with high oxygen and salinity. Summary of the Invention

[0006] One of the objectives of this invention is to provide an iron-nickel based corrosion-resistant injection-production pipe that is resistant to corrosion in high-salt, high-pressure oxygen environments.

[0007] To achieve the above objectives, the present invention provides an iron-nickel based corrosion-resistant injection and production pipe, which contains Fe and unavoidable impurity elements, and also contains the following chemical elements in the following mass percentages:

[0008] 0<C≤0.03%, 0<Si≤0.5%, 0<Mn≤1.0%, Cr: 25~35%, Ni: 30~40%, Mo: 3~5%, Al: 0.1~1.0%, Cu: 0.1~1.0%, Nb: 0.01~0.1%.

[0009] Accordingly, the present invention also provides an iron-nickel based corrosion-resistant injection-production pipe, wherein the mass percentage content of each chemical element is as follows:

[0010] 0 < C ≤ 0.03%, 0 < Si ≤ 0.5%, 0 < Mn ≤ 1.0%, Cr: 25-35%, Ni: 30-40%, Mo: 3-5%, Al: 0.1-1.0%, Cu: 0.1-1.0%, Nb: 0.01-0.1%; the balance is Fe and unavoidable impurity elements.

[0011] Furthermore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the mass percentage content of each chemical element satisfies at least one of the following:

[0012] 0 < C ≤ 0.02%;

[0013] 0 < Si ≤ 0.2%;

[0014] 0 < Mn ≤ 0.5%;

[0015] Cr: 28-33%;

[0016] Ni: 33-38%;

[0017] Al: 0.4–0.7%;

[0018] Cu: 0.3–0.8%;

[0019] Nb: 0.05–0.08%.

[0020] The design principles of each chemical element in the iron-nickel based corrosion-resistant injection-production pipe described in this invention are as follows:

[0021] C: In the iron-nickel-based corrosion-resistant injection-production pipe described in this invention, C is a strong solid solution strengthening element that can improve the strength of austenitic alloys. However, excessively high C content can lead to the presence of large amounts of elements such as M in the austenitic alloy. 23 Precipitated phases such as C6, especially at grain boundaries, tend to form chromium-depleted zones, thereby reducing the alloy's corrosion resistance, particularly its resistance to intergranular corrosion. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe described in this invention, the C element content is controlled below 0.03%, and in some embodiments, the C element content can be further controlled below 0.02%.

[0022] Si: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, Si is an effective deoxidizer and also a strong ferrite-forming element. In austenitic alloys, the δ-ferrite content increases with increasing Si content. However, excessive Si content accelerates the formation and increase of the σ phase of intermetallic compounds in the alloy, leading to increased material brittleness, deterioration of overall mechanical properties, and decreased corrosion resistance. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Si content is controlled below 0.5%, and in some embodiments, the Si content can be further controlled below 0.2%.

[0023] Mn: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, Mn is an effective deoxidizer and desulfurizer. However, excessive Mn can also lead to an increase in intermetallic compound σ phase and carbides in the alloy, thereby deteriorating the overall mechanical properties and corrosion resistance of the alloy. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Mn content is controlled below 1.0%, and in some embodiments, the Mn content can be further controlled below 0.5%.

[0024] Cr: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, Cr is the main element providing corrosion resistance in the alloy. When the Cr content in the alloy is high, a continuous, dense, and highly protective Cr-rich oxide film will form on the alloy surface. Furthermore, as the Cr content increases, the Cr / Fe ratio in the oxide film increases, resulting in better stability and protective performance. However, excessively high Cr content in the alloy can lead to the precipitation of a large amount of σ phase, reducing the toughness and plasticity of the material. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Cr content is controlled at 25-35%, and in some embodiments, the Cr content can be further controlled at 28-33%.

[0025] Ni: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, Ni is an element that stabilizes and expands the austenite phase region in the alloy. As the nickel content in the alloy increases, the Ms point decreases, allowing residual ferrite to be completely eliminated and significantly reducing the tendency for σ phase formation. Therefore, the material possesses excellent toughness, plasticity, and hot workability. Furthermore, Ni can increase the solubility of Cr and Mo elements in the austenite matrix, improving the corrosion resistance of the alloy; Ni itself also possesses excellent corrosion resistance. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Ni content is controlled at 30-40%, and in some embodiments, the Ni content can be further controlled at 33-38%.

[0026] Mo: In the iron-nickel based corrosion-resistant injection-production pipe described in this invention, Mo is an excellent element for resisting localized corrosion. Its mechanism is that MoO4 in the solution after localized corrosion occurs. 2- It adsorbs onto the exposed metal substrate surface after the oxide film breaks down, inhibiting the re-dissolution of the metal. However, excessively high Mo content reduces the hot workability of the alloy. Therefore, in the iron-nickel based corrosion-resistant injection-production pipe described in this invention, the Mo content is controlled at 3-5%.

[0027] Al: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, Al is an effective deoxidizer, which can effectively reduce the oxide inclusion content in the alloy and improve the mechanical properties of the material. Furthermore, adding a certain amount of Al to the alloy can generate a Cr2O3+Al2O3 mixed oxide film on the metal surface, which can significantly improve the oxidation resistance of the material in high-temperature steam. However, excessive Al content will promote the formation of the ferrite phase, forming an austenite / ferrite dual-phase structure, reducing the toughness and hot workability of the alloy. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Al content is controlled at 0.1-1.0%, and in some embodiments, the Al content can be further controlled at 0.4-0.7%.

[0028] Cu: In the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the addition of Cu can significantly reduce the cold work hardening tendency of austenitic alloys and improve their cold forming performance. However, the amount of Cu added should not exceed 1.0%, because excessive Cu will significantly reduce the strength of austenitic alloys. Therefore, in the iron-nickel-based corrosion-resistant injection-production pipe of the present invention, the Cu content is controlled at 0.1-1.0%, and in some embodiments, the Cu content can be further controlled at 0.3-0.8%.

[0029] Nb: In the iron-nickel-based corrosion-resistant injection-production pipe described in this invention, Nb is a strong carbide-forming element. In the alloy, Nb combines with C more readily than Cr to form finely dispersed NbC precipitates. These precipitates can strengthen the alloy by refining its grains and by precipitation, while simultaneously reducing the amount of Cr in the alloy. 23 The formation of C6 leads to chromium-depleted regions at grain boundaries, thereby improving the alloy's resistance to intergranular corrosion. However, excessively high Nb content can cause the precipitation of large amounts of NbC in the alloy, reducing its toughness and plasticity. Therefore, in the iron-nickel-based corrosion-resistant injection and production pipe described in this invention, the Nb content is controlled at 0.01–0.1%, and in some embodiments, the Nb content can be further controlled at 0.05–0.08%.

[0030] The iron-nickel-based corrosion-resistant injection and production pipe of the present invention uses an iron-nickel-based alloy with appropriate amounts of Cr, Ni and other alloying elements. It is an austenitic alloy with excellent corrosion resistance and good formability obtained based on the Fe-Ni-Cr system. The alloy's pitting corrosion resistance is further improved by adding an appropriate amount of Mo, the stability of the oxide film on the alloy surface is improved by adding an appropriate amount of Al, the cold working formability of the alloy is improved by adding an appropriate amount of Cu, and the alloy strength is improved by adding an appropriate amount of Nb.

[0031] Furthermore, in the iron-nickel-based corrosion-resistant injection-production pipe described in this invention, the mass percentage content of each chemical element also satisfies: Ni eq ≥1.15×Cr eq -6.92; where: Ni eq =Ni + 30C + 0.5Mn, Cr eq =Cr+Mo+1.5Si+0.5Nb, where each chemical element is represented by its mass percentage value before the percentage sign.

[0032] In this embodiment, the present invention further ensures the stability of the austenite material by limiting the above-mentioned elemental synergistic relationship.

[0033] Furthermore, in the unavoidable impurity elements of the iron-nickel based corrosion-resistant injection and production pipe described in this invention: P≤0.03%, S≤0.03%.

[0034] The unavoidable impurities in this invention are mainly phosphorus (P) and sulfur (S). Both P and S are associated harmful impurity elements that reduce the alloy's thermoplasticity and toughness, adversely affecting its hot working properties and the toughness and plasticity of the finished pipe. Furthermore, when the content of P and S elements reaches 0.03% or higher, it severely damages the alloy's corrosion resistance. Therefore, in this invention, the content of P and S elements can be controlled below 0.03%. In some embodiments, the content of P and S elements can be further controlled to P ≤ 0.010% and S ≤ 0.005%.

[0035] Furthermore, the microstructure of the iron-nickel-based corrosion-resistant injection and production pipe of the present invention is uniform 10-20 μm equiaxed austenite, which contains dispersed NbC precipitates.

[0036] Furthermore, in the iron-nickel-based corrosion-resistant injection and production pipe described in this invention, its yield strength is 390–1100 MPa, and its impact energy at 0°C is 89–145 J.

[0037] Furthermore, the pitting corrosion rate R of the iron-nickel-based corrosion-resistant injection-production pipe described in this invention under underground compressed air energy storage conditions of 30–90℃ with high salt and high oxygen content is [not specified]. piting ≤0.1mm / a, uniform corrosion rate R gen ≤0.01mm / a.

[0038] The pitting resistance equivalent PRE = Cr + 3.3 × Mo of the iron-nickel based corrosion-resistant injection and production pipe described in this invention can reach 51.

[0039] Another objective of this invention is to provide a method for manufacturing iron-nickel-based corrosion-resistant injection-production pipes. This method has a simple process flow, is easy to control, and, with the addition of a reasonable chemical composition ratio, can produce iron-nickel-based corrosion-resistant injection-production pipes resistant to corrosion in high-salt, high-pressure, and high-oxygen environments.

[0040] To achieve the above objectives, the present invention also proposes a method for manufacturing an iron-nickel based corrosion-resistant injection-production pipe as described above, comprising the following steps:

[0041] Smelting and casting yield ingots;

[0042] Forging the billet into a tube blank;

[0043] Tube blank heating;

[0044] Hot extrusion: The tube blank to be extruded is hot extruded to obtain a rough tube, and then the rough tube is immediately water-cooled at a rate of ≥15℃ / s.

[0045] Solution treatment: The solution treatment temperature is 1050~1150℃, followed by water cooling after heat preservation, with a cooling rate ≥15℃ / s;

[0046] Aging treatment: The aging treatment temperature is 850℃~930℃, the aging treatment time is 6~10min / mm, and water cooling is performed after the heat preservation is completed, with a cooling rate ≥10℃ / s;

[0047] Cold rolling.

[0048] In the manufacturing method described in this invention, the blank to be extruded is hot-extruded to obtain a rough tube, and then the rough tube is immediately water-cooled at a cooling rate of ≥15℃ / s. This is because the grains undergo large plastic deformation during the extrusion process. If the rough tube continues to be kept at a high temperature, recrystallization will occur, causing the grains to become coarser and reducing the cold working performance of the material. Therefore, water cooling with a cooling rate of ≥15℃ / s is used to cool and reduce the temperature of the rough tube.

[0049] Water cooling is controlled after the solution treatment and heat preservation, with a cooling rate ≥15℃ / s. This is because the precipitation temperature range of Cr carbides is 400℃~800℃. If the rough tube remains in this temperature range for too long, a large amount of Cr will be deposited. 23 Carbides such as C6 precipitate along grain boundaries, which severely reduces the toughness of the finished tube. Therefore, water cooling with a cooling rate of ≥15℃ / s is used to rapidly cool the rough tube.

[0050] The aging treatment temperature is controlled at 850℃~930℃ and the aging treatment time is 6~10min / mm because the NbC precipitation temperature range is 850℃~930℃. High temperature and short time precipitation can increase the nucleation rate of the precipitated phase, while inhibiting the growth of the precipitated phase, improving the dispersion of the precipitated phase and reducing the size of the precipitated phase.

[0051] Furthermore, in the tube blank heating step of the manufacturing method described in this invention, the tube blank is heated to an extrusion temperature of 1100-1250°C.

[0052] Furthermore, in the hot extrusion step of the manufacturing method described in this invention, the water cooling rate of the rough tube is 20-25°C / s.

[0053] Furthermore, in the solution treatment step of the manufacturing method described in this invention, the cooling rate of water cooling after the heat preservation is 20-25°C / s.

[0054] Furthermore, in the aging treatment step of the manufacturing method described in this invention, the aging treatment temperature is 900℃~930℃, and the aging treatment time is 6~8min / mm.

[0055] Furthermore, in the cold rolling step of the manufacturing method described in this invention, the cross-section reduction deformation is 20-50%.

[0056] The iron-nickel-based corrosion-resistant injection and production pipe and its manufacturing method described in this invention have the following advantages and beneficial effects:

[0057] The iron-nickel-based corrosion-resistant injection and production pipe of the present invention adds an appropriate amount of Mo to further improve the pitting corrosion resistance of the alloy, adds an appropriate amount of Al to improve the stability of the oxide film on the alloy surface, adds an appropriate amount of Cu to improve the cold working formability of the alloy, and adds an appropriate amount of Nb to improve the alloy strength.

[0058] The iron-nickel-based corrosion-resistant injection and production pipe of the present invention uses water cooling at a specific cooling rate to cool the raw pipe during the manufacturing process, so as to prevent recrystallization that would cause the grains to become coarse and reduce the mechanical properties of the finished pipe.

[0059] The iron-nickel-based corrosion-resistant injection-production pipe of this invention undergoes rapid cooling via water cooling at a specific cooling rate after solution treatment, which can prevent the accumulation of large amounts of Cr. 23 Carbides such as C6 precipitate along grain boundaries to improve the toughness of the finished tube.

[0060] The iron-nickel-based corrosion-resistant injection-production pipe of this invention exhibits excellent resistance to corrosion in high-salt, high-pressure oxygen environments. In some embodiments, its pitting corrosion rate R in underground compressed air energy storage conditions with high salt and high oxygen content at 30–90℃ is [not specified]. piting ≤0.1mm / a, uniform corrosion rate R gen ≤0.01mm / a. Attached Figure Description

[0061] Figure 1 The metallographic image of Embodiment 9 of the present invention is shown. Detailed Implementation

[0062] The following will further explain and illustrate the iron-nickel based corrosion-resistant injection and production pipe and its manufacturing method according to the present invention with reference to specific embodiments and accompanying drawings. However, such explanation and illustration do not constitute an undue limitation on the technical solution of the present invention.

[0063] The iron-nickel-based corrosion-resistant injection-production pipes in Examples 1-12 and the control injection-production pipes in Comparative Examples 1-12 are all seamless pipes with a specification of φ273.05×10.16mm, which are prepared by the following steps:

[0064] (1) Cast the alloy with the composition ratio shown in Table 1 into an ingot with a diameter of 500 mm;

[0065] (2) The ingot is forged at 1150℃ into a tube blank with a diameter of 200mm;

[0066] (3) The tube blank is surface-polished and the center hole is drilled to obtain the tube blank to be extruded;

[0067] (4) Heat the tube blank to be extruded to the extrusion temperature of 1100-1250℃ and keep it warm. The holding time of the tube blank to be extruded can be 1-3 min / mm.

[0068] (5) Apply glass lubricating powder to the surface of the tube blank to be extruded after heat preservation, and at the same time preheat the hot extrusion die, cylinder and rod to 500-600℃ and apply glass lubricating powder.

[0069] (6) The tube blank is extruded by extrusion die to obtain a rough tube. The extrusion ratio can be 1 to 15, for example, the extrusion ratio is 9.0. The extrusion speed can be 20 to 150 mm / s. After extrusion, the rough tube is immediately water-cooled. The cooling rate is not less than 15℃ / s.

[0070] (7) Heat the cooled rough tube to 1050-1150℃ for solution treatment. The holding time can be 1-3 min / mm. After the holding time is completed, water cool it. The cooling rate should not be less than 15℃ / s.

[0071] (8) The raw pipe is aged at 850℃~930℃ for precipitation, and the aging time is 6~10min / mm. After the heat preservation is completed, it is water-cooled with a cooling rate of not less than 10℃ / s.

[0072] (9) The rough tube is cold rolled to reduce the deformation of the cross section by 20-50% to obtain the finished product.

[0073] Table 1 lists the mass percentage of chemical elements in the iron-nickel-based corrosion-resistant injection-production pipes of Examples 1-12 and the comparative injection-production pipes of Comparative Examples 1-12.

[0074] Table 1. (wt%, balance Fe and other unavoidable impurities besides P and S)

[0075]

[0076]

[0077] Table 2 lists the specific process parameters of the iron-nickel based corrosion-resistant injection and production pipes of Examples 1-12 and the comparative injection and production pipes of Comparative Examples 1-12 in the above process steps.

[0078] Table 2

[0079]

[0080]

[0081] To verify the implementation effects of the various embodiments of the present invention, samples were taken from the iron-nickel-based corrosion-resistant injection-production pipes of Examples 1-12 and the comparative injection-production pipes of Comparative Examples 1-12 for mechanical property testing, and the test results are listed in Table 3. Wherein:

[0082] The yield strength data is obtained by processing the manufactured injection and production pipe into an API SPEC 5CT arc-shaped specimen, testing it according to API standards, and taking the average value.

[0083] The full-size Charpy V-impact energy absorption data is obtained by taking full-size V-impact specimens with a cross-sectional area of ​​10*10*55 on the manufactured steel pipe, testing them according to GB / T 229 standard, and taking the average value.

[0084] The corrosion test was conducted in a dynamic high-temperature and high-pressure reactor. A 50mm×20mm×3mm corrosion evaluation sample with a hole (hole diameter 6mm) was machined from the injection and production pipe. The sample was immersed in a liquid in the dynamic high-temperature and high-pressure reactor, which was a 230g / L NaCl solution. The test temperature was set at 70℃, the partial pressure of compressed air was 12MPa (at which point the partial pressure of oxygen was approximately 2.5MPa), and the test time was 240h. The sample weights before and after the test were compared to calculate the uniform corrosion rate. The pitting corrosion pits were analyzed by laser confocal microscopy, and the maximum pitting corrosion rate was calculated.

[0085] Table 3.

[0086]

[0087]

[0088] As shown in Table 3, the yield strength of the injection-production pipes in Examples 1-12 of this invention is ≥390MPa, and the impact energy at 0℃ is ≥89J. Their uniform corrosion rate in 70℃, 230g / L NaCl solution, and 12MPa compressed air is ≤0.008mm / a, and the maximum pitting corrosion rate is ≤0.09mm / a. This fully demonstrates that the iron-nickel based corrosion-resistant injection-production pipes of this invention possess excellent mechanical properties and resistance to corrosion in high-salt, high-pressure oxygen environments.

[0089] In contrast, the Cr content in Comparative Example 1 was insufficient, resulting in lower stability and protective performance of the oxide film.

[0090] The Ni content in Comparative Example 2 was insufficient, and the presence of residual ferrite in the material resulted in insufficient toughness, plasticity, and hot workability.

[0091] In Comparative Example 3, when P and S exceed the upper limit, the impact toughness of the material decreases, and the corrosion resistance of the alloy also decreases.

[0092] The C content in Comparative Example 4 is higher than that of this invention, which leads to the presence of a large amount of elements such as M in the austenitic alloy. 23 Precipitated phases such as C6, especially at grain boundaries, tend to form chromium-depleted zones, thereby reducing the alloy's corrosion resistance, particularly its resistance to intergranular corrosion.

[0093] The insufficient Al content in Comparative Example 5 reduced the material's oxidation resistance in high-temperature steam, resulting in a higher corrosion rate.

[0094] The Mo content in Comparative Example 6 was insufficient, resulting in poor pitting corrosion resistance of the material.

[0095] In Comparative Example 7, the Cu content was insufficient, resulting in severe work hardening of the material and cracks on the surface of the finished pipe after rolling.

[0096] The insufficient Nb content in Comparative Example 8 reduced the strength of the material.

[0097] In Comparative Example 9, the content of Si and Mn elements exceeded the upper limit, resulting in low material toughness.

[0098] In Comparative Example 10, the cooling rate after hot extrusion exceeded the lower limit, resulting in coarse grains, reduced cold working performance of the material, and cracks appearing on the surface of the finished tube after rolling.

[0099] In Comparative Example 11, the cooling rate after solution treatment exceeded the lower limit, resulting in Cr... 23 The large-scale precipitation of carbides such as C6 reduces the material's toughness and corrosion resistance.

[0100] In Comparative Example 12, the aging treatment temperature exceeded the lower limit, leading to Cr... 23 The large-scale precipitation of carbides such as C6 reduces the material's toughness and corrosion resistance.

[0101] also, Figure 1 A photograph of the microstructure of the iron-nickel-based corrosion-resistant injection-production pipe of Example 9 of the present invention is shown. From... Figure 1 It can be seen that it has a uniform 10-20 μm equiaxed austenite, which contains dispersed NbC precipitates.

[0102] It should be noted that the combination of the technical features in this case is not limited to the combination methods described in the claims of this case or the combination methods described in the specific embodiments. All technical features described in this case can be freely combined or combined in any way, unless they contradict each other.

[0103] It should also be noted that the embodiments listed above are merely specific embodiments of the present invention. Obviously, the present invention is not limited to the above embodiments, and similar changes or modifications made thereto are those that can be directly derived or easily conceived by those skilled in the art from the content disclosed in the present invention, and should all fall within the protection scope of the present invention.

Claims

1. A nickel-based corrosion-resistant injection-production pipe, characterized in that, The mass percentage of each chemical element is as follows: 0 < C ≤ 0.03%, 0 < Si ≤ 0.5%, 0 < Mn ≤ 1.0%, Cr: 25-35%, Ni: 30-40%, Mo: 3-5%, Al: 0.1-1.0%, Cu: 0.1-1.0%, Nb: 0.01-0.1%; the balance is Fe and unavoidable impurity elements. The microstructure of the iron-nickel-based corrosion-resistant injection and production pipe is uniform 10-20 μm equiaxed austenite, which contains dispersed NbC precipitates. The pitting rate (Rpiting) of the iron-nickel-based corrosion-resistant injection-production pipe in underground compressed air energy storage conditions with high salinity and high oxygen content at 30–90℃ is ≤0.1 mm / a, and the uniform corrosion rate (Rgen) is ≤0.01 mm / a.

2. The iron-nickel based corrosion-resistant injection-production pipe as described in claim 1, characterized in that, Its mass percentage content of each chemical element satisfies at least one of the following conditions: 0＜C≤0.02％； 0 < Si ≤ 0.2%; 0 < Mn ≤ 0.5%; Cr：28～33％； Ni: 33-38%; Al：0.4～0.7％； Cu: 0.3–0.8%; Nb: 0.05–0.08%.

3. The iron-nickel based corrosion-resistant injection-production pipe as described in claim 1, characterized in that, Its mass percentage content of each chemical element also meets the following requirements: Ni eq ≥1.15×Cr eq -6.92; where: Ni eq =Ni + 30C + 0.5Mn, Cr eq =Cr+Mo+1.5Si+0.5Nb, where each chemical element is represented by its mass percentage value before the percentage sign.

4. The iron-nickel based corrosion-resistant injection-production pipe as described in claim 1, characterized in that, Among unavoidable impurity elements: P ≤ 0.03%, S ≤ 0.03%.

5. The iron-nickel based corrosion-resistant injection-production pipe as described in claim 1, characterized in that, Its yield strength is 390–1100 MPa, and its impact energy at 0℃ is 89–145 J.

6. The method for manufacturing the iron-nickel based corrosion-resistant injection-production pipe as described in any one of claims 1-5, characterized in that, Including the following steps: Smelting and casting yield ingots; Forging the billet into a tube blank; Tube blank heating; Hot extrusion: The tube blank to be extruded is hot extruded to obtain a rough tube, and then the rough tube is immediately water-cooled at a cooling rate of ≥15℃ / s. Solution treatment: The solution treatment temperature is 1050~1150℃, followed by water cooling after heat preservation, with a cooling rate ≥15℃ / s; Aging treatment: The aging treatment temperature is 850℃~930℃, the aging treatment time is 6~10min / mm, and water cooling is performed after the heat preservation is completed, with a cooling rate ≥10℃ / s; Cold rolling.

7. The manufacturing method as described in claim 6, characterized in that, In the tube blank heating step, the tube blank is heated to the extrusion temperature of 1100-1250℃.

8. The manufacturing method as described in claim 6, characterized in that, During the hot extrusion process, the water cooling rate for the rough tube is 20–25 °C / s.

9. The manufacturing method as described in claim 6, characterized in that, In the solution treatment step, the cooling rate of water cooling after the heat preservation is 20-25℃ / s.

10. The manufacturing method as described in claim 6, characterized in that, In the aging process, the aging temperature is 900℃~930℃ and the aging time is 6~8min / mm.

11. The manufacturing method as described in claim 6, characterized in that, In the cold rolling process, the cross-section is reduced by 20% to 50%.

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