Aluminum alloy screen pipe and manufacturing method and application thereof

Abstract

The invention discloses an aluminum alloy screen pipe and a manufacturing method and application thereof. The manufacturing method comprises the steps that raw material components are smelted and cast into a pipe blank; the pipe blank is sequentially subjected to three-stage homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment and two-stage artificial aging treatment, and an aluminum alloy screen pipe blank is obtained; and plasma is adopted for cutting the aluminum alloy screen pipe blank, and the aluminum alloy screen pipe is manufactured. The aluminum alloy screen pipe comprises, by weight, 3.5%-6.5% of Zn, 3.8%-4.9% of Cu, 1.2%-1.8% of Mg, 0.3%-0.9% of Mn, smaller than or equal to 0.15% of Ti, smaller than or equal to 0.15% of Zr and the balance Al and inevitable impurities. The prepared aluminum alloy screen pipe is good in seam shape quality, good in tensile property and heat resistance and excellent in extrusion strength.

Description

Technical Field

[0001] The present invention belongs to the technical field of oil pipe manufacturing, and relates to an aluminum alloy screen pipe, a manufacturing method and an application thereof. Background Art

[0002] Ultra-deep carbonate rock oil and gas exploration and development face extreme tests such as ultra-depth, ultra-high temperature, ultra-high pressure, and high corrosion. In addition, due to problems such as poor wellbore stability and sand production in oil and gas layers, it is required that the completion screen pipe has good sand control performance, weight reduction and drag reduction, high temperature resistance, corrosion resistance, easy drilling and grinding, etc. Aluminum alloy materials are advantageous metal materials that can be used in the manufacture of oil screen pipes, but aluminum alloy screen pipes still have problems such as insufficient thermal strength of materials, poor slot quality, insufficient sand control performance, and small extrusion resistance. Summary of the Invention

[0003] Aiming at the problems existing in the prior art, the present invention provides an aluminum alloy screen pipe, a manufacturing method and an application thereof, so as to solve the technical problems of insufficient thermal strength of materials, poor slot quality, insufficient sand control performance, and small extrusion resistance existing in the production and manufacture of aluminum alloy screen pipes in the prior art.

[0004] The present invention is realized through the following technical solutions:

[0005] An aluminum alloy screen pipe, by weight percentage, includes Zn: 3.5% - 6.5%, Cu: 3.8% - 4.9%, Mg: 1.2% - 1.8%, Mn: 0.3% - 0.9%, Ti ≤ 0.15%, Zr ≤ 0.15%, and the balance is Al and unavoidable impurities.

[0006] The manufacturing method of the above-mentioned aluminum alloy screen pipe includes the following steps:

[0007] S1: Weigh and mix raw materials according to the weight percentage, carry out smelting, and cast into a tube blank;

[0008] S2: The tube blank is sequentially subjected to three-stage homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment, and two-stage artificial aging treatment to obtain an aluminum alloy screen pipe blank;

[0009] S3: The aluminum alloy screen pipe blank is cut by plasma to obtain the aluminum alloy screen pipe.

[0010] Preferably, the three-stage homogenization treatment is specifically: heating the tube blank to 400 - 415 °C and holding for 6 - 14 h; then heating to 435 - 450 °C and holding for 6 - 12 h; finally heating to 450 - 475 °C and holding for 6 - 10 h; finally naturally cooling to room temperature to complete the homogenization treatment process.

[0011] Preferably, during the three-stage homogenization treatment process, the heating rate is 10 - 20 °C / min.

[0012] Preferably, the variable cross-section extrusion process is specifically as follows: the tube blank after three-stage homogenization treatment is heated to 400 - 420 °C, held for 20 min and then extruded, the extrusion ratio is greater than 18, and the extrusion speed is 35 mm / min.

[0013] Preferably, the two-stage solution treatment process is specifically as follows: the tube blank after variable cross-section extrusion is heated to 460 - 470 °C, held for 1 - 2 h and then heated to 480 - 490 °C, held for 1 - 1.5 h, and then cooled to complete the two-stage solution treatment.

[0014] Preferably, during the two-stage solution treatment process, the heating rate is greater than 20 °C / min, and the cooling rate is 30 - 50 °C / s.

[0015] Preferably, the process of the two-stage artificial aging treatment is specifically as follows: held at 165 - 175 °C for 3 - 20 h and held at 185 - 195 °C for 6 - 30 h.

[0016] Preferably, during the cutting process of the aluminum alloy screen tube blank with plasma, the diameter of the plasma nozzle is 0.1 - 0.36 mm, and the cutting seam width is 0.2 - 0.5 mm.

[0017] The application of the above-mentioned aluminum alloy screen tube in the field of oil and gas exploration and development.

[0018] Compared with the prior art, the present invention has the following beneficial technical effects:

[0019] The present invention discloses an aluminum alloy screen pipe. By weight percentage, it includes Zn: 3.5% - 6.5%, Cu: 3.8% - 4.9%, Mg: 1.2% - 1.8%, Mn: 0.3% - 0.9%, Ti ≤ 0.15%, Zr ≤ 0.15%, and the balance is Al and inevitable impurities. There is no need to add precious metal element Ag, and the cost is low. By controlling the weight percentage of elements, the solution strengthening and aging strengthening of Zn element, the precipitation strengthening of Cu and Mg elements, the solution strengthening and grain refinement of Mn element at the solution treatment temperature, and the grain refinement of the composite addition of Ti and Zr are utilized to give full play to the composite effects such as solution strengthening, precipitation strengthening, and grain refinement, effectively improving the thermal strength of the aluminum alloy screen pipe material. The addition of Zn and Mg elements mainly exists as η(MgZn2) phase in the alloy. A ternary T(Al2Mg3Zn3) phase can also be formed between Zn, Mg and Al. Both η phase and T phase have strong aging strengthening effects. The addition of Cu synergistically strengthens with Zn and Mg, promotes the nucleation rate of precipitation phases during the aging process of the alloy, refines the alloy grains, and to a certain extent also improves the strengthening effects of binary θ(Al2Cu) phase and high-concentration ternary solid solution S(Al2CuMg) phase. Cu atoms can also replace Zn elements in η(MgZn2) phase and T(Al2Mg3Zn3) phase to form AlZnMgCu quaternary phase, reducing the potential difference between the intragranular and grain boundary of the alloy and improving the corrosion resistance of the alloy. The economical strengthening element Mn forms metastable phase Al6Mn dispersion phase with Al during the casting process, hinders the dynamic recrystallization during the hot extrusion process of aluminum alloy and the recrystallization process during the solution process, significantly refines the recrystallized grains, weakens the negative impact of impurity element Fe on the alloy, and improves the heat resistance strength by delaying the over-aging process. After homogenization treatment, Zr combines with Al to form fine and dispersed high-melting-point Al3Zr particles, pinning dislocations, effectively hindering recrystallization and grain growth during hot working process, and effectively improving the toughness and thermal strength of the alloy.

[0020] In addition, the present invention also discloses a manufacturing method of an aluminum alloy screen pipe, which includes smelting the above components and casting them into a tube blank; sequentially subjecting the tube blank to homogenization treatment, variable cross-section extrusion treatment, double-stage solution treatment, and artificial aging treatment to obtain an aluminum alloy screen pipe blank; and cutting the aluminum alloy screen pipe blank by using plasma to obtain the aluminum alloy screen pipe. In the process of the present invention, heat treatment processes such as multi-stage homogenization treatment, double-stage solution treatment, and double-stage artificial aging are adopted, which greatly eliminate segregation and inhomogeneity inside the matrix, significantly promote the remelting of the unmelted eutectic phase inside the aluminum alloy matrix, and the obtained alloy structure is that micron crystal phases formed by solidification, sub-micron or nano-scale dispersed phases precipitated at high temperature, and nano-scale metastable phases precipitated during aging are dispersed in the Al matrix. Therefore, while maintaining high strength, the thermal strength is improved. In addition, by means of double-stage solution treatment and double-stage artificial aging, the potential of solution strengthening and precipitation strengthening of the material is fully exploited in a stepwise heating manner, while shortening the entire solution aging process duration, improving the processing efficiency, and reducing the manufacturing cost. At the same time, during the manufacturing process, the aluminum alloy screen pipe blank is cut by using plasma, effectively controlling the width of each part of the slit, ensuring the quality of the slit, further improving the corrosion resistance of the slotted screen pipe, having a more stable seepage area, reducing the pressure loss when the oil fluid flows through the screen pipe, and increasing the crude oil recovery rate during the production process. There is no heat-affected zone around the screen pipe slit, and the intended strong and tough properties of the screen pipe matrix material are completely retained. There is no problem of sudden width change at both ends of the slit of a conventional screen pipe, and the edge has a smooth transition, enhancing the material and structural strength of the screen pipe. The outer-narrow and inner-wide micro-trapezoidal slit obtained by controlling the regular swing of the plasma during the processing process ensures that fine sand grains in the oil fluid can smoothly pass through the slit, reduces the probability of natural blockage of the slit cavity, and increases the service life of the aluminum alloy screen pipe.

[0021] Further, the three-stage homogenization treatment is specifically as follows: heating the tube blank to 400 - 415 °C and holding for 6 - 14 h; then heating to 435 - 450 °C and holding for 6 - 12 h; finally heating to 450 - 475 °C and holding for 6 - 10 h; and finally naturally cooling to room temperature to complete the homogenization treatment process, which can reduce as-cast segregation and make the composition more uniform.

[0022] Further, the variable cross-section extrusion treatment process is specifically as follows: heating the tube blank after three-stage homogenization treatment to 400 - 420 °C, holding for 20 min and then performing extrusion, with an extrusion ratio greater than 18 and an extrusion speed of 35 mm / min, which can form the variable cross-section tube blank in one step.

[0023] Further, the specific process of the double-stage solution treatment is as follows: heat the tube blank after variable cross-section extrusion to 460 - 470 °C, keep it warm for 1 - 2 h, then heat it to 480 - 490 °C and keep it warm for 1 - 1.5 h, and then cool it to complete the double-stage solution treatment, which can make alloying elements fully dissolve in the matrix.

[0024] Further, during the double-stage solution treatment, the heating rate is greater than 20 °C / min, and the cooling rate is 30 - 50 °C / s, and a supersaturated solid solution can be obtained.

[0025] Further, the specific process of the double-stage artificial aging treatment is as follows: keep it warm at 165 - 175 °C for 3 - 20 h, and keep it warm at 185 - 195 °C for 6 - 30 h, which can make nano-strengthening phases precipitate fully.

[0026] Further, during the cutting of the aluminum alloy screen tube blank by plasma, the diameter of the plasma nozzle is 0.1 - 0.36 mm, and the cutting seam width is 0.2 - 0.5 mm, which can make the seam type have better sand control performance. Description of the Drawings

[0027] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention, and thus should not be regarded as limiting the scope. For those of ordinary skill in the art, without creative efforts, other related drawings can also be obtained based on these drawings.

[0028] Figure 1 It is a schematic flow chart of a manufacturing method of an aluminum alloy screen tube in the present invention. Detailed Embodiments

[0029] To enable those skilled in the art to understand the features and effects of the present invention, the terms and expressions mentioned in the specification and claims will be generally described and defined below. Unless otherwise specified, all technical and scientific terms used herein have the ordinary meanings understood by those skilled in the art regarding the present invention. In case of conflict, the definitions in this specification shall prevail.

[0030] The theories or mechanisms described and disclosed herein, whether correct or incorrect, shall not limit the scope of the present invention in any way, that is, the content of the present invention can be implemented without being limited by any specific theory or mechanism.

[0031] In this text, all features defined in the form of numerical ranges or percentage ranges, such as numerical values, quantities, contents, and concentrations, are only for the sake of brevity and convenience. Accordingly, the description of a numerical range or percentage range should be regarded as having covered and specifically disclosed all possible sub-ranges and individual numerical values within the range (including integers and fractions).

[0032] In this text, unless otherwise specified, terms such as "comprising", "including", "containing", "having", or similar terms cover the meanings of "consisting of" and "consisting essentially of". For example, "A comprises a" covers the meanings of "A comprises a and others" and "A consists only of a".

[0033] In this text, for the sake of concise description, not all possible combinations of all technical features in each embodiment or example are described. Therefore, as long as there is no contradiction in the combination of these technical features, the technical features in each embodiment or example can be combined arbitrarily, and all possible combinations should be considered as within the scope described in this specification.

[0034] The present invention provides an aluminum alloy screen pipe, which, by weight percentage, comprises 3.5% - 6.5% of Zn, 3.8% - 4.9% of Cu, 1.2% - 1.8% of Mg, 0.3% - 0.9% of Mn, Ti ≤ 0.15%, Zr ≤ 0.15%, and the balance is Al and unavoidable impurities. The unavoidable impurities include Fe and Si, wherein, by weight percentage, Fe ≤ 0.05% and Si ≤ 0.05%.

[0035] In addition, the present invention also discloses a manufacturing method of an aluminum alloy screen pipe, comprising the following steps:

[0036] S1: Smelt the components in the present invention and cast them into a tube blank;

[0037] S2: Subject the tube blank to homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment, and two-stage artificial aging treatment in sequence to obtain an aluminum alloy screen pipe blank;

[0038] Wherein, during the homogenization treatment process, the tube blank is heated to 400 - 415 °C and held for 6 - 14 h; then heated to 435 - 450 °C and held for 6 - 12 h; finally heated to 450 - 475 °C and held for 6 - 10 h; and finally naturally cooled to room temperature to complete the homogenization treatment process. During the homogenization treatment process, the heating rate is 10 - 20 °C / min.

[0039] The specific process of the variable cross-section extrusion treatment is as follows: Heat the tube blank that has undergone homogenization treatment to 400 - 420 °C, hold for 20 min and then perform extrusion, the extrusion ratio is greater than 18, and the extrusion speed is 35 mm / min.

[0040] The specific process of the double-stage solution treatment is as follows: The tube blank after variable cross-section extrusion is heated to 460-470 °C, held for 1-2 h, then heated to 480-490 °C, held for 1-1.5 h, and then cooled to complete the double-stage solution treatment. During the double-stage solution treatment, the heating rate is greater than 20 °C / min, and the cooling rate is 30-50 °C / s.

[0041] The specific process of the double-stage artificial aging treatment is as follows: It is held at 165-175 °C for 3-20 h and at 185-195 °C for 6-30 h.

[0042] S3: The aluminum alloy screen tube blank is cut by plasma to obtain the aluminum alloy screen tube.

[0043] During the process of cutting the aluminum alloy screen tube blank by plasma, the diameter of the plasma nozzle is 0.1-0.36 mm, and the cutting seam width is 0.2-0.5 mm.

[0044] The alloy composition design of the present invention is simple, without the need to add precious metal elements such as Ag, and the cost is low. By controlling the appropriate weight percentages of each element, the solution strengthening and aging strengthening of the Zn element, the precipitation strengthening of the Cu and Mg elements, the solution strengthening and grain refinement of the Mn element at the solution treatment temperature, and the grain refinement of the composite addition of Ti and Zr are utilized to fully exert the composite effects such as solution strengthening, precipitation strengthening, and grain refinement, thereby improving the thermal strength of the aluminum alloy screen tube material. The addition of Zn and Mg elements mainly exists as η(MgZn2) phase in the alloy. A ternary T(Al2Mg3Zn3) phase can also be formed between Zn, Mg, and Al. Both the η phase and the T phase have strong aging strengthening effects. The addition of Cu synergistically strengthens with Zn and Mg, promotes the nucleation rate of the precipitation phase during the alloy aging process, refines the alloy grains, and to a certain extent also improves the strengthening effects of the binary θ(Al2Cu) phase and the high-concentration ternary solid solution S(Al2CuMg) phase. Cu atoms can also replace Zn elements in the η(MgZn2) phase and the T(Al2Mg3Zn3) phase to form an AlZnMgCu quaternary phase, reducing the potential difference between the intragranular and grain boundary of the alloy and improving the corrosion resistance of the alloy. The economical strengthening element Mn forms a metastable phase Al6Mn dispersion phase with Al during the casting process, hinders the dynamic recrystallization during the hot extrusion process of the aluminum alloy and the recrystallization process during the solution process, significantly refines the recrystallized grains, weakens the negative impact of the impurity element Fe on the alloy, and improves the heat resistance strength by delaying the over-aging process. After homogenization treatment, Zr combines with Al to form fine and dispersed high-melting-point Al3Zr particles, pinning dislocations, effectively hindering recrystallization and grain growth during the hot working process, and effectively improving the toughness and thermal strength of the alloy.

[0045] In addition, the present invention adopts heat treatment processes such as multi-stage homogenization treatment, double-stage solution treatment, and double-stage artificial aging in the process, which greatly eliminates segregation and inhomogeneity inside the matrix, significantly promotes the remelting of the unmelted eutectic phase inside the aluminum alloy matrix, and the obtained alloy structure is that micron crystal phases formed by solidification, sub-micron or nano-scale dispersed phases precipitated at high temperature, and nano-scale metastable phases precipitated during aging are dispersedly distributed on the Al matrix. Thus, while maintaining high strength, the thermal strength is improved. In addition, by means of double-stage solution treatment and double-stage artificial aging, the potential of solution strengthening and precipitation strengthening of the material is fully exploited in a stepped heating manner, while shortening the entire solution aging process duration, improving the processing efficiency and reducing the manufacturing cost. The high-strength heat-resistant aluminum alloy screen pipe of the present invention has a slit width as low as 0.2 mm and a surface roughness of the slit cavity as small as 1.5 μm. The better slit quality further improves the corrosion resistance of the slotted screen pipe, has a more stable seepage area, reduces the pressure loss when the oil fluid flows through the screen pipe, and improves the crude oil recovery rate during the production process. There is no heat-affected zone around the screen pipe slit, and the intended strong and tough properties of the screen pipe matrix material are completely retained. There is no problem of sudden width change at both ends of the slit of the conventional screen pipe, and the edge has a smooth transition, enhancing the material and structural strength of the screen pipe. The outer-narrow and inner-wide micro-trapezoidal slit obtained by controlling the regular swing of the plasma during the processing process ensures that fine sand grains in the oil fluid can smoothly pass through the slit, reduces the probability of natural blockage of the slit cavity, and improves the service life of the aluminum alloy screen pipe

[0046] Compared with the material composition of conventional screen pipes, the present invention has a higher Zn content (Zn: 3.5 - 6.5%) and Cu content (3.8 - 4.9%), a certain Mg content (1.2 - 1.8%), a lower Mn (0.3 - 0.9%), trace amounts of Ti (≤0.15%) and Zr (≤0.15%) with aluminum as the matrix in the alloy formula. The composition is simple and the cost is low, making full use of the synergistic strengthening effects of Zn, Cu, and Mg elements in both solid solution and precipitation aspects. With the above composition combined with double-stage solution treatment and double-stage aging heat treatment means, not only the comprehensive performance of the product is improved, but also a flexible extrusion production process can be adopted, while reducing the heat treatment duration and increasing the productivity. In addition, the drillability of the present invention is far superior to that of conventional screen pipes, improving the safety factor for dealing with downhole accidents and avoiding malignant accidents such as damage to the wellbore caused by removing the pipe string or even well abandonment. In addition, the product produced by the present invention with a high Zn and Cu content combined with double-stage solution treatment and double-stage aging process has high strength and improved heat resistance, enabling the aluminum alloy screen pipe to have good high-temperature resistance performance and still maintain good collapse resistance in the high-temperature environment of deep wells and ultra-deep wells. The high-strength heat-resistant aluminum alloy screen pipe of the present invention has a slit width as low as 0.2 mm and a surface roughness of the slit cavity as small as 1.5 μm. The better slit quality further improves the corrosion resistance of the slotted screen pipe, has a more stable flow area, reduces the pressure loss when the oil fluid flows through the screen pipe, and improves the crude oil recovery rate during the production process. There is no heat-affected zone around the screen pipe slits, and there is no sudden change in the width at both ends of the slits like conventional screen pipes. The edges have a smooth transition, enhancing the material and structural strength of the screen pipe. The outer-narrow and inner-wide micro-trapezoidal slits obtained by controlling the regular swing of the plasma during the processing ensure that fine sand grains in the oil fluid can pass through the slits smoothly, reduce the probability of natural blockage of the slit cavity, and improve the service life of the aluminum alloy screen pipe.

[0047] The R of the aluminum alloy screen pipe prepared by the present invention t0.2 ≥550 MPa, R m ≥630 MPa, δ≥10.0%, having good tensile properties; the yield strength of the screen pipe after heat exposure at 120°C for 500 hours is not less than 385 MPa, having good heat resistance performance; in addition, the slit width of the screen pipe is 0.2 - 0.5 mm, and the surface roughness of the slit cavity is 1.5 - 6.4 μm, which can effectively block sand and gravel, and at the same time has a relatively high surface smoothness and is not easy to jam the screen pipe.

[0048] The following further elaborates the present invention in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not 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 defined by the appended claims of this application.

[0049] In the following examples, conventional instruments and equipment in the art are used. For the experimental methods without specific conditions noted in the following examples, they are generally carried out under conventional conditions or according to the conditions recommended by the manufacturer. In the following examples, various raw materials are used. Unless otherwise specified, commercially available products are used, and their specifications are conventional specifications in the art. In the specification of the present invention and the following examples, unless otherwise specified, "%" represents weight percentage, "parts" represents weight parts, and the ratio represents weight ratio.

[0050] Example 1

[0051] A high-strength heat-resistant aluminum alloy screen pipe of the present invention, its chemical composition by weight percentage includes: 4% of Zn, 4.2% of Cu, 1.5% of Mg, 0.8% of Mn, 0.08% of Ti, 0.15% of Zr, and the rest is Al and inevitable impurities; among them, the inevitable impurities include 0.05% of Fe and 0.05% of Si accounting for the total weight of the aluminum alloy.

[0052] The manufacturing method of the above high-strength heat-resistant aluminum alloy screen pipe is as follows: smelt and refine the above raw materials outside the furnace and then cast to obtain a tube blank. The tube blank is subjected to three-stage homogenization treatment at 410°C×12h, 450°C×10h, and 470°C×8h, and naturally cooled to room temperature. Then, it is kept warm at 420°C for 20 minutes and then extruded and deformed. The extrusion ratio is greater than 18, and the extrusion speed is 3mm / s; then it is subjected to two-stage solution quenching treatment at 470°C×2h and 490°C×1.5h, cooled to room temperature at a cooling speed of 50°C / s, and then artificially aged at 175°C for 12h and artificially aged at 195°C for 12h in sequence; then the artificially aged tube body is subjected to plasma cutting, and the nozzle diameter is 0.1mm.

[0053] The mechanical properties of the high-strength heat-resistant aluminum alloy screen pipe obtained by the above manufacturing method reach: the tensile strength is 635MPa, the yield strength is 554MPa, and the elongation is 11%. After being exposed at 120°C for 500h, the tensile properties reach: the yield strength is 395MPa. The screen pipe slot width is 0.2mm, and the surface roughness of the slot cavity is 1.5μm

[0054] Example 2

[0055] A high-strength heat-resistant aluminum alloy screen pipe of the present invention, its chemical composition by weight percentage includes: 6% of Zn, 3.5% of Cu, 1.5% of Mg, 0.5% of Mn, 0.13% of Ti, 0.15% of Zr, and the rest is Al and inevitable impurities; among them, the inevitable impurities include 0.05% of Fe and 0.05% of Si accounting for the total weight of the aluminum alloy.

[0056] The manufacturing method of the above high-strength heat-resistant aluminum alloy screen pipe is as follows: After smelting and refining outside the furnace for the above raw materials, a pipe blank is obtained by casting. The pipe blank is subjected to three-stage homogenization treatment at 400°C for 14 h, 435°C for 12 h, and 455°C for 10 h, and then naturally cooled to room temperature. Then, it is held at 410°C for 20 min and then extruded and deformed. The extrusion ratio is greater than 18, and the extrusion speed is 6 mm / s. Then, it is subjected to two-stage solution quenching treatment at 460°C for 2 h and 480°C for 1.5 h, cooled to room temperature at a cooling speed of 40°C / s, and then artificially aged at 165°C for 20 h and artificially aged at 185°C for 30 h in sequence. Then, the artificially aged pipe body is subjected to plasma cutting, and the nozzle diameter is 0.23 mm.

[0057] The mechanical properties of the high-strength heat-resistant aluminum alloy screen pipe obtained by the above manufacturing method reach:

[0058] The tensile strength is 632 MPa, the yield strength is 560 MPa, and the elongation is 13%. After being exposed at 120°C for 500 h, the tensile properties reach: the yield strength is 400 MPa. The screen pipe slot width is 0.35 mm, and the surface roughness of the slot cavity is 3.5 μm.

[0059] Example 3

[0060] A high-strength heat-resistant aluminum alloy screen pipe of the present invention, its chemical composition in weight percentage includes: 5% of Zn, 4.5% of Cu, 1.3% of Mg, 0.9% of Mn, 0.13% of Ti, 0.07% of Zr, and the rest is Al and inevitable impurities; among them, the inevitable impurities include 0.05% of Fe and 0.03% of Si accounting for the total weight of the aluminum alloy.

[0061] The manufacturing method of the above high-strength heat-resistant aluminum alloy screen pipe is as follows: After smelting and refining outside the furnace for the above raw materials, a pipe blank is obtained by casting. The pipe blank is subjected to three-stage homogenization treatment at 415°C for 10 h, 450°C for 10 h, and 475°C for 10 h, and then naturally cooled to room temperature. Then, it is held at 400°C for 40 min and then extruded and deformed. The extrusion ratio is greater than 18, and the extrusion speed is 4 mm / s. Then, it is subjected to two-stage solution quenching treatment at 465°C for 2 h and 485°C for 1 h, cooled to room temperature at a cooling speed of 45°C / s, and then artificially aged at 170°C for 15 h and artificially aged at 190°C for 10 h in sequence. Then, the artificially aged pipe body is subjected to plasma cutting, and the nozzle diameter is 0.36 mm.

[0062] The mechanical properties of the high-strength heat-resistant aluminum alloy screen pipe obtained by the above manufacturing method reach: the tensile strength is 640 MPa, the yield strength is 560 MPa, and the elongation is 10%. After being exposed at 120°C for 500 h, the tensile properties reach: the yield strength is 391 MPa. The screen pipe slot width is 0.5 mm, and the surface roughness of the slot cavity is 6.4 μm.

[0063] Example 4

[0064] A manufacturing method of an aluminum alloy screen pipe, comprising the following steps:

[0065] S1: Smelt the raw materials and cast them into a tube blank; wherein, the raw materials by weight percentage include 3.5% of Zn, 3.8% of Cu, 1.2% of Mg, 0.3% of Mn, 0.1% of Ti, 0.1% of Zr, and the balance is Al and inevitable impurities. The inevitable impurities include Fe and Si. Among them, by weight percentage, Fe is 0.05% and Si is 0.05%.

[0066] S2: Subject the tube blank to three-stage homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment and two-stage artificial aging treatment in sequence to obtain an aluminum alloy screen pipe blank;

[0067] Among them, the specific process of the three-stage homogenization treatment is: heat the tube blank to 400°C and keep it warm for 14h; then heat it to 435°C and keep it warm for 12h; finally heat it to 450°C and keep it warm for 10h; finally cool it naturally to room temperature to complete the homogenization treatment process. During the homogenization treatment process, the heating rate is 10°C / min.

[0068] The specific process of the variable cross-section extrusion treatment is: heat the tube blank after homogenization treatment to 400°C, keep it warm for 20min and then perform extrusion, the extrusion ratio is 18.5, and the extrusion speed is 35mm / min.

[0069] The specific process of the two-stage solution treatment is: heat the tube blank after variable cross-section extrusion to 460°C, keep it warm for 2h and then heat it to 480°C, keep it warm for 1.5h, and then perform cooling to complete the two-stage solution treatment. During the two-stage solution treatment process, the heating rate is 22°C / min and the cooling rate is 30°C / s.

[0070] The specific process of the two-stage artificial aging treatment is: keep it warm at 165°C for 20h and keep it warm at 185°C for 30h.

[0071] S3: Cut the aluminum alloy screen pipe blank by using plasma to obtain the aluminum alloy screen pipe. During the cutting process, the diameter of the plasma nozzle is 0.1mm and the cutting seam width is 0.2mm.

[0072] The R of the aluminum alloy screen pipe obtained in this example t0.2 is 560MPa, R m is 630MPa, δ is 12%; the yield strength of the screen pipe after heat exposure at 120°C for 500 hours is 390MPa; in addition, the seam width of the screen pipe is 0.2mm and the surface roughness of the seam cavity is 1.54μm.

[0073] Example 5

[0074] A manufacturing method of an aluminum alloy screen pipe, comprising the following steps:

[0075] S1: Smelt the raw materials and cast them into a tube blank; wherein, the raw materials by weight percentage include 5% of Zn, 4.5% of Cu, 1.5% of Mg, 0.6% of Mn, 0.09% of Ti, 0.13% of Zr, and the balance is Al and inevitable impurities. The inevitable impurities include Fe and Si. Among them, by weight percentage, Fe is 0.04% and Si is 0.03%.

[0076] S2: Subject the tube blank to three-stage homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment and two-stage artificial aging treatment in sequence to obtain an aluminum alloy screen pipe blank;

[0077] Among them, the specific process of the three-stage homogenization treatment is: heat the tube blank to 412 °C and hold for 10 h; then heat to 440 °C and hold for 10 h; finally heat to 460 °C and hold for 8 h; finally cool naturally to room temperature to complete the homogenization treatment process. During the homogenization treatment process, the heating rate is 15 °C / min.

[0078] The specific process of the variable cross-section extrusion treatment is: heat the tube blank after homogenization treatment to 415 °C, hold for 20 min and then extrude. The extrusion ratio is 20 and the extrusion speed is 35 mm / min.

[0079] The specific process of the two-stage solution treatment is: heat the tube blank after variable cross-section extrusion to 465 °C, hold for 1.2 h and then heat to 485 °C, hold for 1 h, and then cool to complete the two-stage solution treatment. During the two-stage solution treatment process, the heating rate is 22 °C / min and the cooling rate is 40 °C / s.

[0080] The specific process of the two-stage artificial aging treatment is: hold at 170 °C for 10 h and hold at 190 °C for 20 h.

[0081] S3: Cut the aluminum alloy screen pipe blank by using plasma to obtain the aluminum alloy screen pipe. During the cutting process, the diameter of the plasma nozzle is 0.2 mm and the cutting seam width is 0.35 mm.

[0082] The R of the aluminum alloy screen pipe obtained in this example t0.2 is 580 MPa, R m is 640 MPa, δ is 10.5%; the yield strength of the screen pipe after thermal exposure at 120 °C for 500 hours is 390 MPa; in addition, the seam width of the screen pipe is 0.35 mm and the surface roughness of the seam cavity is 3.5 μm.

[0083] Example 6

[0084] A manufacturing method of an aluminum alloy screen pipe, comprising the following steps:

[0085] S1: Smelt the raw materials and cast them into a tube blank; wherein, the raw materials by weight percentage include 6.5% of Zn, 4.9% of Cu, 1.8% of Mg, 0.9% of Mn, 0.13% of Ti, 0.1% of Zr, and the balance is Al and inevitable impurities. The inevitable impurities include Fe and Si. Among them, by weight percentage, Fe is 0.05% and Si is 0.05%.

[0086] S2: Subject the tube blank to three-stage homogenization treatment, variable cross-section extrusion treatment, two-stage solution treatment, and two-stage artificial aging treatment in sequence to obtain an aluminum alloy screen pipe blank;

[0087] Among them, the specific process of the three-stage homogenization treatment is: heat the tube blank to 415 °C and hold for 6 h; then heat to 450 °C and hold for 6 h; finally heat to 475 °C and hold for 6 h; finally cool naturally to room temperature to complete the homogenization treatment process. During the homogenization treatment process, the heating rate is 20 °C / min.

[0088] The specific process of the variable cross-section extrusion treatment is: heat the tube blank after homogenization treatment to 420 °C, hold for 20 min and then extrude, the extrusion ratio is 18.5, and the extrusion speed is 35 mm / min.

[0089] The specific process of the two-stage solution treatment is: heat the tube blank after variable cross-section extrusion to 470 °C, hold for 1 h and then heat to 490 °C, hold for 1 h, and then cool to complete the two-stage solution treatment. During the two-stage solution treatment process, the heating rate is 22 °C / min, and the cooling rate is 50 °C / s.

[0090] The specific process of the two-stage artificial aging treatment is: hold at 175 °C for 3 h and hold at 195 °C for 6 h.

[0091] S3: Cut the aluminum alloy screen pipe blank by plasma to obtain the aluminum alloy screen pipe. During the cutting process, the diameter of the plasma nozzle is 0.36 mm, and the cutting seam width is 0.5 mm.

[0092] The R of the aluminum alloy screen pipe obtained in this example t0.2 is 560 MPa, R m is 640 MPa, δ is 20.0%; the yield strength of the screen pipe after thermal exposure at 120 °C for 500 hours is 392 MPa; in addition, the seam width of the screen pipe is 0.5 mm, and the surface roughness of the seam cavity is 6.4 μm.

[0093] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.

[0094] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit the protection scope of the present invention. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. An aluminum alloy screen pipe, characterized in that, By weight percentage, it includes Zn: 3.5% - 6.5%, Cu: 3.8% - 4.9%, Mg: 1.2% - 1.8%, Mn: 0.3% - 0.9%, Ti ≤ 0.15%, Zr ≤ 0.15%, and the balance is Al and unavoidable impurities.

2. A manufacturing method of the aluminum alloy screen pipe described in claim 1, characterized in that, It includes the following steps: S1: Weigh the raw materials according to the weight percentage, conduct smelting, and cast into a tube blank. S2: The tube blank is successively subjected to three - stage homogenization treatment, variable cross - section extrusion treatment, two - stage solution treatment, and two - stage artificial aging treatment to obtain an aluminum alloy screen tube blank. S3: The aluminum alloy screen tube blank is cut by plasma to obtain the aluminum alloy screen tube.

3. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, The specific three - stage homogenization treatment is as follows: Heat the tube blank to 400 - 415 °C and hold for 6 - 14 h; then heat to 435 - 450 °C and hold for 6 - 12 h; finally heat to 450 - 475 °C and hold for 6 - 10 h; finally cool naturally to room temperature to complete the homogenization treatment process.

4. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, During the three - stage homogenization treatment process, the heating rate is 10 - 20 °C / min.

5. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, The specific variable cross - section extrusion treatment process is as follows: Heat the tube blank that has undergone three - stage homogenization treatment to 400 - 420 °C, hold for 20 min and then conduct extrusion. The extrusion ratio is greater than 18, and the extrusion speed is 35 mm / min.

6. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, The specific two - stage solution treatment process is as follows: Heat the tube blank that has undergone variable cross - section extrusion to 460 - 470 °C, hold for 1 - 2 h and then heat to 480 - 490 °C, hold for 1 - 1.5 h, and then conduct cooling to complete the two - stage solution treatment.

7. According to the manufacturing method of the aluminum alloy screen pipe described in claim 6, characterized in that, During the two - stage solution treatment process, the heating rate is greater than 20 °C / min, and the cooling rate is 30 - 50 °C / s.

8. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, The specific two - stage artificial aging treatment process is as follows: Hold at 165 - 175 °C for 3 - 20 h, and hold at 185 - 195 °C for 6 - 30 h.

9. According to the manufacturing method of the aluminum alloy screen pipe described in claim 2, characterized in that, During the process of cutting the aluminum alloy screen tube blank by plasma, the diameter of the plasma nozzle is 0.1 - 0.36 mm, and the cutting seam width is 0.2 - 0.5 mm.

10. Application of the aluminum alloy screen pipe described in claim 1 in the field of oil and gas exploration and development.

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