Composite coated pressure seamless steel pipe

Abstract

The utility model discloses a kind of composite coating pressure seamless steel pipes, it is related to seamless steel pipe technical field, including pressure-bearing steel pipe mechanism, the pressure-bearing steel pipe mechanism further includes seamless steel pipe, the end of the seamless steel pipe is provided with connecting flange.The utility model forms cooperative protection by multilayer composite coating, the nickel-based alloy coating of inner wall base layer is closely attached by metallurgical bonding with matrix, resist high-temperature fluid scour and block corrosion medium penetration;The continuous anticorrosive film of middle layer epoxy resin forms, further isolates medium and steel pipe ontology;Surface layer polytetrafluoroethylene coating reduces fluid conveying resistance, while resistant to strong corrosive medium erosion, three layers of coating synergistic effect, maintain structural stability under high pressure, corrosive working condition, surface heat conduction coating utilizes the high thermal conductivity of aluminium nitride, accelerate the heat dissipation of pipeline when high-temperature fluid conveying, avoid coating aging caused by local overheating, adapt steam, high-temperature oil and other medium transmission.

Description

Technical Field

[0001] This utility model relates to the field of seamless steel pipe technology, specifically to a composite coated pressure-bearing seamless steel pipe. Background Technology

[0002] Traditional pressure-bearing seamless steel pipes are widely used in high-pressure fluid transportation, such as oil and gas, steam, chemical media transmission, and municipal water supply and drainage. Basic corrosion protection is achieved through a single anti-corrosion coating, such as epoxy coal tar pitch or galvanized layer. The pipe body strength is relied upon to withstand fluid pressure, ensuring the continuity of media transmission in various industrial and civil engineering projects.

[0003] However, when transporting highly corrosive media such as sulfur-containing natural gas and acid / alkali solutions, or under high-pressure pulse and high-temperature conditions, traditional single coatings are prone to cracking and peeling due to media erosion and temperature changes, leading to corrosion and perforation of the steel pipe body. This not only reduces the pressure-bearing capacity but also requires frequent shutdowns for maintenance, seriously affecting long-term stable operation under complex conditions. Therefore, a composite-coated pressure-bearing seamless steel pipe is proposed. Utility Model Content

[0004] This invention provides a composite coated pressure-bearing seamless steel pipe to solve the problems mentioned in the background art.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by this utility model is as follows:

[0006] A composite-coated pressure-bearing seamless steel pipe includes a pressure-bearing steel pipe structure, which further includes a seamless steel pipe with a connecting flange at its end and a fixing bolt inside the connecting flange; and a composite coating structure, which includes a surface thermally conductive and anti-corrosion coating and an inner wall base layer, wherein the surface thermally conductive and anti-corrosion coating is sprayed on the surface of the seamless steel pipe and the inner wall base layer is sprayed on the inner wall of the seamless steel pipe.

[0007] A further improvement of the present invention is that the pressure-bearing steel pipe mechanism further includes a connecting groove, which is formed on the inner wall of one end of the seamless steel pipe.

[0008] A further improvement of this utility model is that: a first sealing ring is fixedly connected to the inner wall of the connecting groove, and a metal corrugated pipe is fixedly connected to the other end of the seamless steel pipe.

[0009] A further improvement of this utility model is that: a second sealing ring is fixedly connected to the end of the metal bellows; in the connected state, the surface of the metal bellows is inserted into the inside of the connecting groove, and one side of the first sealing ring overlaps with the surface of the second sealing ring.

[0010] A further improvement of the present invention is that the composite coating mechanism further includes a middle layer and an inner surface layer, wherein the middle layer is sprayed on the surface of the inner wall base layer and the inner surface layer is sprayed on the surface of the middle layer.

[0011] A further improvement of the present invention is that the surface thermally conductive and corrosion-resistant coating is an aluminum nitride silicon resin composite coating with a thickness of 0.1-0.15mm and a thermal conductivity ≥180W / m·K.

[0012] A further improvement of the present invention is that the inner wall base layer is a nickel-based alloy coating with a thickness of 0.1-0.3 mm, and is applied using a supersonic flame spraying process.

[0013] A further improvement of the present invention is that the middle layer is an epoxy resin powder coating with a thickness of 0.2-0.4 mm; and the inner surface layer is a polytetrafluoroethylene coating with a thickness of 0.05-0.1 mm.

[0014] Due to the adoption of the above technical solution, the technological progress achieved by this utility model compared to the prior art is as follows:

[0015] This utility model provides a composite coated pressure-bearing seamless steel pipe. Through a multi-layer composite coating, synergistic protection is achieved. The nickel-based alloy coating on the inner wall base adheres tightly to the substrate via metallurgical bonding, resisting high-temperature fluid erosion and blocking the penetration of corrosive media. The middle layer of epoxy resin forms a continuous anti-corrosion film, further isolating the medium from the steel pipe body. The surface polytetrafluoroethylene coating reduces fluid transport resistance while resisting strong corrosive media erosion. The three coatings work synergistically to maintain structural stability under high pressure and corrosive conditions. The surface thermally conductive coating utilizes the high thermal conductivity of aluminum nitride to accelerate heat dissipation during high-temperature fluid transport, preventing coating aging caused by localized overheating. It is suitable for transporting media such as steam and high-temperature oils. In the connection structure, the metal bellows cooperates with the sealing ring. When the internal pressure of the pipe increases, the metal bellows is affected by the pressure, pushing the sealing ring to press tightly, enhancing sealing performance and forming an adaptive sealing structure to prevent leakage, improve pressure-bearing stability, and enhance its pressure-bearing performance. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the assembly state of this utility model.

[0017] Figure 2 This is a schematic diagram of the single-section main view structure of this utility model;

[0018] Figure 3 This is a side view of the present invention.

[0019] Figure 4 This is a cross-sectional view of the connection point of this utility model;

[0020] Figure 5 For the present utility model Figure 4 Enlarged structural diagram at point A in the middle.

[0021] In the diagram: 11. Seamless steel pipe; 12. Connecting flange; 13. Fixing bolt; 14. Connecting groove; 15. First sealing ring; 16. Metal bellows; 17. Second sealing ring; 21. Surface thermal conductive and anti-corrosion coating; 22. Inner wall base layer; 23. Middle layer; 24. Inner surface layer. Detailed Implementation

[0022] The present invention will be further described in detail below with reference to embodiments:

[0023] Example 1

[0024] like Figure 1-5 As shown, this utility model provides a composite coated pressure-bearing seamless steel pipe, including a pressure-bearing steel pipe mechanism, which further includes a seamless steel pipe 11. The end of the seamless steel pipe 11 is provided with a connecting flange 12, and the inside of the connecting flange 12 is provided with fixing bolts 13. The composite coating mechanism includes a surface thermally conductive and anti-corrosion coating 21 and an inner wall base layer 22. The surface thermally conductive and anti-corrosion coating 21 is sprayed on the surface of the seamless steel pipe 11, and the inner wall base layer 22 is sprayed on the inner wall of the seamless steel pipe 11.

[0025] In this embodiment, during connection, the metal bellows 16 at one end of the seamless steel pipe 11 is inserted into the connecting groove 14 of another steel pipe. The first sealing ring 15 and the second sealing ring 17 fit tightly to form an initial seal. After alignment by the connecting flange 12, the interface is fixed by tightening with fixing bolts 13. When transporting the medium, the seamless steel pipe 11 body bears the fluid pressure. The inner wall base layer 22, formed by supersonic flame spraying, blocks the direct contact between the medium and the steel pipe. The epoxy resin powder coating of the middle layer 23 further isolates the penetration of corrosive media. The polytetrafluoroethylene coating of the inner surface layer 24 reduces the frictional resistance of the medium and resists strong chemical corrosion. The surface thermally conductive and anti-corrosion coating 21 accelerates the heat dissipation of the steel pipe and avoids coating aging caused by high temperature. When the internal pressure of the pipe increases, the metal bellows 16 is affected by the pressure and pushes the sealing ring to press tightly, enhancing the sealing performance and forming an adaptive sealing structure to prevent leakage and ensure that the interface is leak-free under dynamic pressure. The multi-layer coating and sealing design work together to ensure stable operation under complex working conditions.

[0026] Example 2

[0027] like Figure 1-5As shown, based on Embodiment 1, this utility model provides a technical solution: Preferably, the pressure-bearing steel pipe mechanism further includes a connecting groove 14, which is opened on the inner wall of one end of the seamless steel pipe 11. A first sealing ring 15 is fixedly connected to the inner wall of the connecting groove 14, and a metal corrugated pipe 16 is fixedly connected to the other end of the seamless steel pipe 11. A second sealing ring 17 is fixedly connected to the end of the metal corrugated pipe 16. In the connected state, the surface of the metal corrugated pipe 16 is inserted into the interior of the connecting groove 14, and one side of the first sealing ring 15 overlaps with the surface of the second sealing ring 17.

[0028] In this embodiment, by inserting the metal bellows 16 at one end of the seamless steel pipe 11 into the connecting groove 14 of another steel pipe, the first sealing ring 15 and the second sealing ring 17 are tightly fitted to form an initial seal. After alignment by the connecting flange 12, the interface is fixed by tightening with the fixing bolts 13. When conveying the medium, the seamless steel pipe 11 body bears the fluid pressure. The inner wall base layer 22 is blocked from direct contact between the medium and the steel pipe by the nickel-based alloy layer formed by supersonic flame spraying. The epoxy resin powder coating of the middle layer 23 further isolates the penetration of corrosive media. The polytetrafluoroethylene coating of the inner surface layer 24 reduces the frictional resistance of the medium and resists strong chemical corrosion.

[0029] Example 3

[0030] like Figure 1-5 As shown, based on Embodiment 1, this utility model provides a technical solution: Preferably, the composite coating mechanism further includes a middle layer 23 and an inner surface layer 24. The middle layer 23 is sprayed on the surface of the inner wall base layer 22, and the inner surface layer 24 is sprayed on the surface of the middle layer 23. The surface thermally conductive and corrosion-resistant coating 21 is an aluminum nitride silicon resin composite coating with a thickness of 0.1-0.15 mm and a thermal conductivity ≥180 W / m·K. The inner wall base layer 22 is a nickel-based alloy coating with a thickness of 0.1-0.3 mm, which is applied using a supersonic flame spraying process. The middle layer 23 is an epoxy resin powder coating with a thickness of 0.2-0.4 mm. The inner surface layer 24 is a polytetrafluoroethylene coating with a thickness of 0.05-0.1 mm.

[0031] In this embodiment, the surface thermally conductive and anti-corrosion coating 21 accelerates heat dissipation from the steel pipe, preventing coating aging caused by high temperatures. When the internal pressure of the pipe increases, the metal bellows 16 is affected by the pressure, pushing the sealing ring to press tightly, enhancing the sealing performance, forming an adaptive sealing structure, preventing leakage, and ensuring that the interface is leak-free under dynamic pressure. The multi-layer coating and sealing design work together to ensure stable operation under complex working conditions.

[0032] The working principle of this composite-coated pressure-bearing seamless steel pipe will be explained in detail below.

[0033] like Figure 1-5As shown, during connection, the metal bellows 16 at one end of the seamless steel pipe 11 is inserted into the connecting groove 14 of the other steel pipe. The first sealing ring 15 and the second sealing ring 17 fit tightly to form an initial seal. After alignment by the connecting flange 12, the interface is fixed by tightening with the fixing bolts 13. When transporting the medium, the seamless steel pipe 11 body bears the fluid pressure. The inner wall base layer 22, formed by supersonic flame spraying, blocks the direct contact between the medium and the steel pipe. The epoxy resin powder coating of the middle layer 23 further isolates the penetration of corrosive media. The polytetrafluoroethylene coating of the inner surface layer 24 reduces the frictional resistance of the medium and resists strong chemical corrosion. The surface thermally conductive and anti-corrosion coating 21 accelerates the heat dissipation of the steel pipe and avoids coating aging caused by high temperature. When the internal pressure of the pipe increases, the metal bellows 16 is affected by the pressure and pushes the sealing ring to press tightly, enhancing the sealing performance and forming an adaptive sealing structure to prevent leakage and ensure that the interface is leak-free under dynamic pressure. The multi-layer coating and sealing design work together to ensure stable operation under complex working conditions.

[0034] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the protection scope of the present invention.

Claims

1. A composite-coated pressure-bearing seamless steel pipe, characterized in that: include The pressure-bearing steel pipe structure further includes a seamless steel pipe (11), the end of which is provided with a connecting flange (12), and the inside of the connecting flange (12) is provided with fixing bolts (13). The pressure-bearing steel pipe mechanism also includes a connecting groove (14), which is opened on the inner wall of one end of the seamless steel pipe (11). A first sealing ring (15) is fixedly connected to the inner wall of the connecting groove (14), and a metal bellows (16) is fixedly connected to the other end of the seamless steel pipe (11). A second sealing ring (17) is fixedly connected to the end of the metal bellows (16). In the connected state, the surface of the metal bellows (16) is inserted into the inside of the connecting groove (14), and one side of the first sealing ring (15) overlaps with the surface of the second sealing ring (17). A composite coating mechanism, comprising a surface thermally conductive and corrosion-resistant coating (21) and an inner wall base layer (22), wherein the surface thermally conductive and corrosion-resistant coating (21) is sprayed on the surface of the seamless steel pipe (11) and the inner wall base layer (22) is sprayed on the inner wall of the seamless steel pipe (11); The composite coating structure also includes an intermediate layer (23) and an inner surface layer (24), wherein the intermediate layer (23) is sprayed on the surface of the inner wall base layer (22) and the inner surface layer (24) is sprayed on the surface of the intermediate layer (23).

2. The composite-coated pressure-bearing seamless steel pipe according to claim 1, characterized in that: The surface thermally conductive and corrosion-resistant coating (21) is an aluminum nitride silicon resin composite coating with a thickness of 0.1-0.15 mm and a thermal conductivity ≥180 W / m·K.

3. The composite-coated pressure-bearing seamless steel pipe according to claim 1, characterized in that: The inner wall base layer (22) is a nickel-based alloy coating with a thickness of 0.1-0.3 mm, and is applied using a supersonic flame spraying process.

4. The composite-coated pressure-bearing seamless steel pipe according to claim 1, characterized in that: The middle layer (23) is an epoxy resin powder coating with a thickness of 0.2-0.4 mm; the inner surface layer (24) is a polytetrafluoroethylene coating with a thickness of 0.05-0.1 mm.

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