A laser additive manufacturing method for corrosion protection of a gas-tight thread sealing surface

Abstract

This invention provides a method for laser additive manufacturing of corrosion-resistant airtight threaded sealing surfaces. The method includes the following steps: S1: pre-treating the airtight threaded sealing surface; S2: drying nickel-based alloy powder; S3: using a fiber laser to perform laser scanning on the pre-treated airtight threaded sealing surface, while simultaneously sending the dried nickel-based alloy powder to the laser spot area. The nickel-based alloy powder melts and solidifies with the airtight threaded sealing surface substrate to form a corrosion-resistant layer. This invention significantly improves the corrosion resistance of airtight threads in a sodium chloride atmosphere by laser-coating a layer of corrosion-resistant functional material onto the surface of the airtight threaded sealing surface. The manufactured airtight threads exhibit significant advantages such as strong corrosion resistance, high airtightness, and long service life.

Description

Technical Field

[0001] This invention relates to the field of laser additive manufacturing technology, and in particular to a method for anti-corrosion laser additive manufacturing of an airtight threaded sealing surface. Background Technology

[0002] An airtight threaded connection for oil tubing (or simply airtight threaded connection) is a sealing device specifically designed for threaded connections in oil tubing. It primarily prevents oil and gas leakage from the tubing connection under high pressure, ensuring wellbore integrity and operational safety. The core of the airtight threaded connection lies in achieving excellent airtightness through a special thread structure and sealing design.

[0003] Salt cavern compressed air energy storage is a large-scale physical energy storage technology that uses underground salt caverns as air storage chambers to store and release electrical energy by compressing and releasing air. After being stored in the salt cavern, the compressed air will contain sodium chloride. When the high-pressure air containing sodium chloride flows in the pipeline, it will corrode the airtight thread sealing surface and seriously deteriorate the sealing performance of the airtight thread.

[0004] Currently, electroplating, chemical plating and other methods are widely used to prepare the anti-corrosion layer of the airtight thread sealing surface; however, the above methods generally have defects such as thin coating, easy peeling, and environmental pollution, and cannot guarantee the corrosion resistance, airtightness and service life of the airtight thread.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The purpose of this invention is to provide a laser additive manufacturing method for corrosion-resistant gasket sealing surfaces. By using a laser to fused a layer of anti-corrosion functional material onto the surface of the gasket sealing surface, the corrosion resistance, airtightness, and service life of the gasket are greatly improved.

[0007] This invention provides a method for laser additive manufacturing of an airtight threaded sealing surface for corrosion protection, comprising the following steps: S1: Pre-treatment of the airtight threaded sealing surface; S2: Drying nickel-based alloy powder; S3: Use a fiber laser to perform laser scanning on the pre-treated airtight threaded sealing surface. At the same time as the laser scanning, dry nickel-based alloy powder is sent to the laser spot area. The nickel-based alloy powder melts and solidifies with the airtight threaded sealing surface substrate to form an anti-corrosion layer.

[0008] In step S1, the material of the airtight threaded substrate can be carbon steel, etc.; the pretreatment includes: turning the airtight threaded sealing surface to leave a thickness of 0.5-2.5 mm (e.g., 0.9-1.5 mm) for the anti-corrosion layer processing. The surface roughness of the airtight threaded sealing surface after pretreatment is Ra < 1.6 μm.

[0009] In step S2, the main chemical composition of the nickel-based alloy powder is as follows: Ni 58-62%, Cr 20-23%, Mo 8-10%, Nb 3.2-4.0%; preferably, the main chemical composition of the nickel-based alloy powder is as follows: Ni 58-60%, Cr 20-22%, Mo 8-9%, Nb 3.2-3.8%. The particle size of the nickel-based alloy powder can be 180-220 mesh. The drying temperature can be 90-150 ℃, and the drying time can be 1-2 h.

[0010] In step S3, the laser spot diameter during laser scanning can be 3-5 mm; the laser power can be 2-3 KW, for example, 2-2.8 KW; the laser scanning speed can be 3000-5000 mm / min, for example, 3000-4700 mm / min; the overlap during laser scanning can be 1.5-2.5 mm, for example, 1.5-2 mm; and the powder feeding speed of the nickel-based alloy powder can be 40-60 g / min, for example, 48-55 g / min. Furthermore, argon gas is used as the protective gas during laser scanning, with a purity of 99.999% and a flow rate of 15-20 L / min. The thickness of the formed anti-corrosion layer can be controlled to 0.5-2.5 mm, for example, 0.9-1.3 mm, depending on actual needs. Further, the formed anti-corrosion layer can be precision machined to achieve a surface roughness Ra of 1.3-1.5.

[0011] This invention improves the corrosion resistance and wear resistance of the substrate by cladding a functional material onto the sealing surface of the airtight thread and using a high-energy-density laser beam to melt it and form a metallurgical bond with the substrate. It has advantages such as low dilution rate, dense structure, high bonding force with the substrate, and small deformation, which greatly improves the corrosion resistance of the airtight thread in a sodium chloride atmosphere, and at the same time significantly improves the airtightness and service life of the airtight thread. Attached Figure Description

[0012] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0013] Figure 1 This is a partial structural diagram of an airtight thread.

[0014] Explanation of reference numerals in the attached figures: 1, 2: Sealing surface. Detailed Implementation

[0015] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0016] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0017] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example 1 Combination Figure 1 As shown, the laser additive manufacturing method for corrosion protection of the airtight threaded sealing surface in this embodiment includes the following steps: S1: Preprocessing The sealing surfaces 1 and 2 of the airtight thread (made of carbon steel) are machined, leaving a thickness of 1 mm for subsequent anti-corrosion layer processing; then, the surface roughness is tested, and the surface roughness of sealing surfaces 1 and 2 is Ra < 1.6 μm.

[0019] S2: Drying The nickel-based alloy powder was dried. The main chemical composition of the nickel-based alloy powder is as follows: Ni 58%, Cr 22%, Mo 9%, Nb 3.5%. The particle size of the nickel-based alloy powder is 200 mesh, the drying temperature is 120 ℃, and the drying time is 2 h.

[0020] The dried nickel-based alloy powder is loaded into the powder feeder and blown to the side of the cladding gun head by argon gas.

[0021] S3: Laser Processing A fiber laser is used to scan the sealing surfaces 1 and 2 of the hermetic thread after the pretreatment in step S1. At the same time as the laser scanning, the dried nickel-based alloy powder is fed to the laser spot area. The laser spot size during the laser scanning is 5 mm, the laser power is 2.5 KW, the laser scanning speed is 4000 mm / min, the overlap is 2 mm, the powder feeding speed of the nickel-based alloy powder is 50 g / min, and the flow rate of the protective gas (argon, purity 99.999%) is 20 L / min. The nickel-based alloy powder melts and solidifies with the hermetic thread substrate to form an anti-corrosion layer.

[0022] The formed anti-corrosion layer was precision machined, and the anti-corrosion layers of sealing surface 1 and sealing surface 2 after precision machining were inspected. The inspection results are as follows: the thickness of the anti-corrosion layer is 1.0 mm, the average surface roughness Ra=1.3um, and there are no visible pores or cracks on the surface.

[0023] Example 2 Combination Figure 1 As shown, the laser additive manufacturing method for corrosion protection of the airtight threaded sealing surface in this embodiment includes the following steps: S1: Preprocessing The sealing surfaces 1 and 2 of the airtight thread (made of carbon steel) are machined, leaving a thickness of 1.5 mm for subsequent anti-corrosion layer processing; then, the surface roughness is tested, and the surface roughness of sealing surfaces 1 and 2 is Ra < 1.6 μm.

[0024] S2: Drying The nickel-based alloy powder was dried. The main chemical composition of the nickel-based alloy powder is as follows: Ni 58%, Cr 20%, Mo 8%, Nb 3.2%. The particle size of the nickel-based alloy powder is 180 mesh, the drying temperature is 90 ℃, and the drying time is 1 h.

[0025] The dried nickel-based alloy powder is loaded into the powder feeder and blown to the side of the cladding gun head by argon gas.

[0026] S3: Laser Processing A fiber laser is used to scan the sealing surfaces 1 and 2 of the hermetic thread after the pretreatment in step S1. At the same time as the laser scanning, the dried nickel-based alloy powder is fed to the laser spot area. The laser spot size during the laser scanning is 3 mm, the laser power is 2 KW, the laser scanning speed is 3000 mm / min, the overlap is 1.5 mm, the powder feeding speed of the nickel-based alloy powder is 55 g / min, and the flow rate of the protective gas (argon, purity 99.999%) is 15 L / min. The nickel-based alloy powder melts and solidifies with the hermetic thread substrate to form an anti-corrosion layer.

[0027] The formed anti-corrosion layer was precision machined, and the anti-corrosion layers of sealing surface 1 and sealing surface 2 after precision machining were inspected. The inspection results are as follows: the thickness of the anti-corrosion layer is 1.3 mm, the average surface roughness Ra=1.5um, and there are no visible pores or cracks on the surface.

[0028] Example 3 Combination Figure 1 As shown, the laser additive manufacturing method for corrosion protection of the airtight threaded sealing surface in this embodiment includes the following steps: S1: Preprocessing The sealing surfaces 1 and 2 of the airtight thread (made of carbon steel) are machined, leaving a thickness of 0.9 mm for subsequent anti-corrosion layer processing; then, the surface roughness is tested, and the surface roughness of sealing surfaces 1 and 2 is Ra < 1.6 μm.

[0029] S2: Drying The nickel-based alloy powder was dried. The main chemical composition of the nickel-based alloy powder is as follows: Ni 60%, Cr 22%, Mo 9%, Nb 3.8%. The particle size of the nickel-based alloy powder is 220 mesh. The drying temperature is 150 ℃ and the drying time is 1.5 h.

[0030] The dried nickel-based alloy powder is loaded into the powder feeder and blown to the side of the cladding gun head by argon gas.

[0031] S3: Laser Processing A fiber laser is used to scan the sealing surfaces 1 and 2 of the hermetic thread after the pretreatment in step S1. At the same time as the laser scanning, the dried nickel-based alloy powder is fed to the laser spot area. The laser spot size during the laser scanning is 3.5 mm, the laser power is 2.8 KW, the laser scanning speed is 4700 mm / min, the overlap is 1.7 mm, the powder feeding speed of the nickel-based alloy powder is 48 g / min, and the flow rate of the protective gas (argon, purity 99.999%) is 20 L / min. The nickel-based alloy powder melts and solidifies with the hermetic thread substrate to form an anti-corrosion layer.

[0032] The formed anti-corrosion layer was precision machined, and the anti-corrosion layers of sealing surface 1 and sealing surface 2 after precision machining were inspected. The inspection results are as follows: the thickness of the anti-corrosion layer is 0.9 mm, the average surface roughness Ra=1.4 um, and there are no visible pores or cracks on the surface.

[0033] Compare with Example 1 Except for replacing the nickel-based alloy powder in Example 1 with alloy powder (main chemical composition as follows: Ni 40%, Cr 15%, Mo 3%, Nb 5%), the rest is the same as in Example 1.

[0034] The anti-corrosion layer was tested using the method in Example 1. The test results are as follows: the thickness of the anti-corrosion layer is 1.0 mm, the average surface roughness Ra is 1.3 μm, and visible pores are present on the surface.

[0035] Compare with Example 2 Except for the laser processing conditions in step S3, the rest is the same as in Example 1.

[0036] The laser processing conditions for this comparative example are as follows: the laser spot size during laser scanning is 2 mm, the laser power is 2.8 KW, the laser scanning speed is 5000 mm / min, the overlap is 1 mm, the powder feeding speed of the nickel-based alloy powder is 30 g / min, and the flow rate of the protective gas (argon, purity 99.999%) is 10 L / min.

[0037] Experimental Example 1 The airtight threads manufactured using Examples 1-3 and Comparative Examples 1-2 were tested; the test conditions were as follows: pressure 4000 psi, pressure holding time 30 min.

[0038] The results showed that the airtight threads processed using Examples 1-3 had better airtightness and could maintain good airtightness under a pressure of 4000 psi, while the airtight threads of Comparative Examples 1 and 2 showed varying degrees of leakage.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method of corrosion resistant laser additive manufacturing of a hermetically gaged threaded seal face, the method comprising: Includes the following steps: ​ S1: Pre-treatment of the airtight threaded sealing surface; S2: Drying nickel-based alloy powder; S3: Use a fiber laser to perform laser scanning on the pre-treated airtight threaded sealing surface. At the same time as the laser scanning, dry nickel-based alloy powder is sent to the laser spot area. The nickel-based alloy powder melts and solidifies with the airtight threaded sealing surface substrate to form an anti-corrosion layer.

2. The corrosion resistant laser additive manufacturing method of a hermetically gaged seal face according to claim 1, wherein, Pre-treatment includes: machining the airtight threaded sealing surface to leave a thickness of 0.8-1.2 mm for the anti-corrosion layer processing.

3. The corrosion resistant laser additive manufacturing method of a hermetically gaged seal face according to claim 1, wherein, The surface roughness of the pretreated airtight thread sealing surface is Ra < 1.6 μm.

4. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The material of the airtight threaded base is carbon steel.

5. The corrosion resistant laser additive manufacturing method of a hermetically gaged seal face according to claim 1, wherein, The main chemical composition of nickel-based alloy powder is as follows: Ni 58-62%, Cr 20-23%, Mo 8-10%, Nb 3.2-4.0%.

6. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The particle size of the nickel-based alloy powder is 180-220 mesh.

7. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The laser spot diameter during laser scanning is 3-5 mm, the laser power is 2-3 KW, and the laser scanning speed is 3000-5000 mm / min.

8. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The feeding rate of nickel-based alloy powder is 40-60 g / min.

9. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The overlap during laser scanning is 1.5-2.5 mm.

10. The corrosion resistant laser powder bed fusion method of sealing a gas tight thread face according to claim 1, wherein, The thickness of the anti-corrosion layer is 0.5-2.5 mm.

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