A new type of high-temperature and high-pressure resistant seamless steel pipe

Abstract

The utility model discloses a novel high temperature and high pressure resistant seamless steel pipe, including the pipe body, the pipe body is integrated seamless structure, and the pipe body is constituted by base layer, high temperature resistance layer and high pressure resistance reinforcing layer, and the base layer is base material layer, adopts chromium molybdenum vanadium alloy steel to be made, and its chemical composition is according to mass percentage ratio for: Cr: 10% 15%, Mo: 2% 5%, V: 0.5% 1.5%, C: 0.15% 0.3%, Si: 0.2% 0.6%, Mn: 0.5% 1.2%, and the rest is Fe and unavoidable impurity. The utility model base layer adopts chromium molybdenum vanadium alloy steel, and cooperates inner wall alumina-zirconia composite ceramic coating, can bear 800 1000 DEG C high temperature environment, and the high temperature upper limit of traditional seamless steel pipe is improved by 30% or more, and ceramic coating can effectively insulate high temperature medium and the direct contact of base layer, and slows down high temperature corrosion.

Description

Technical Field

[0001] This utility model relates to the field of seamless steel pipes, specifically to a new type of seamless steel pipe that is resistant to high temperature and high pressure. Background Technology

[0002] Seamless steel pipes are widely used in many industrial applications due to their advantages such as seamlessness and uniform mechanical properties. However, in harsh working conditions such as petroleum cracking, high-temperature boilers, and aero-engine pipelines, where high temperatures (typically exceeding 600°C) and high pressures (typically exceeding 10MPa) are present, traditional seamless steel pipes face several shortcomings: First, insufficient high-temperature resistance. Traditional steel pipes are mostly made of ordinary carbon steel or conventional alloy steel, whose crystal structure is prone to change under high-temperature environments, leading to a significant decrease in strength and hardness, and long-term use is prone to creep and deformation. Second, limited high-pressure resistance. The simple wall structure of conventional seamless steel pipes makes them prone to local stress concentration under high pressure, which can lead to cracks, leaks, and other safety hazards. Third, it is difficult to simultaneously achieve corrosion resistance and high-temperature and high-pressure resistance. Some improved high-temperature resistant steel pipes, while improving temperature adaptability, have reduced corrosion resistance to the medium, shortening their service life. Therefore, those skilled in the art provide a new type of high-temperature and high-pressure resistant seamless steel pipe to solve the problems mentioned in the background art. Utility Model Content

[0003] To solve the above-mentioned technical problems, this utility model provides a novel high-temperature and high-pressure resistant seamless steel pipe, including a pipe body. The pipe body is an integrated seamless structure, consisting of a base layer, a high-temperature resistant layer, and a high-pressure resistant reinforcing layer. The base layer is a matrix material layer made of chromium-molybdenum-vanadium alloy steel, and its chemical composition by mass percentage is: Cr: 10%-15%, Mo: 2%-5%, V: 0.5%-1.5%, C: 0.15%-0.3%, Si: 0.2%-0.6%, Mn: 0.5%-1.2%, with the remainder being Fe and unavoidable impurities. The inner wall of the base layer is provided with spiral guide grooves with a depth of 0.5mm-1mm and a pitch of 20mm-50mm. The high-temperature resistant layer is a ceramic composite coating applied to the inner wall of the base layer with a thickness of 0.1mm-0.3mm, which is prepared by plasma spraying. The high-pressure resistant reinforcing layer is a high-strength carbon fiber braided layer wrapped around the outer wall of the base layer with a braiding density of 90%-98%.

[0004] Preferably, the wall thickness of the tube body is 5mm-20mm.

[0005] Preferably, the ceramic composite coating is an alumina-zirconia composite coating, wherein the mass percentage of zirconia is 30%-50%.

[0006] Preferably, the outer side of the carbon fiber braided layer is coated with a high-temperature resistant resin protective layer, the thickness of which is 0.2mm-0.4mm.

[0007] Preferably, a spiral heat exchange tube is wound around the outer surface of the tube body, a fixing cover is installed at one end of the spiral heat exchange tube, and a fan is installed inside the fixing cover.

[0008] The technical effects and advantages of this utility model are as follows: 1. The base layer of this utility model is made of chromium-molybdenum-vanadium alloy steel, combined with an inner wall alumina-zirconia composite ceramic coating, which can withstand a high temperature environment of 800-1000℃, which is more than 30% higher than the upper limit of high temperature resistance of traditional seamless steel pipes. Moreover, the ceramic coating can effectively isolate the high temperature medium from direct contact with the base layer and slow down high temperature corrosion.

[0009] 2. The base material of this utility model has high strength, and the high-strength carbon fiber braided layer on the outer wall can further disperse the stress on the pipe wall under high pressure, thereby increasing the upper limit of the high pressure resistance of the steel pipe to 25MPa, which is more than 50% higher than that of traditional steel pipes of the same specification. At the same time, the lightweight characteristics of carbon fiber material avoid the increase in self-weight caused by simply thickening the pipe wall.

[0010] 3. The design of the guide channel of this utility model not only reduces the damage to the coating caused by the scouring of the medium, but also enhances the anti-torsion performance. The high-temperature resistant resin protective layer on the outside can protect the carbon fiber braided layer from external environmental erosion, extend the overall service life, and increase the service life by 2-3 times compared with traditional steel pipes. Attached Figure Description

[0011] Figure 1 This is a schematic diagram of the structure of this application; Figure 2 This is a schematic diagram of the structure of the tube body in this application; In the diagram: 1. Pipe body; 2. Base layer; 3. High-temperature resistant layer; 4. High-pressure resistant reinforcing layer; 5. Guide channel; 6. Spiral heat exchange pipe; 7. Fixing cover; 8. Fan. Detailed Implementation

[0012] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. The embodiments of the present invention are given for illustrative and descriptive purposes only, and are not intended to be exhaustive or to limit the present invention to the disclosed forms. Many modifications and variations will be apparent to those skilled in the art. The embodiments were chosen and described to better illustrate the principles and practical applications of the present invention, and to enable those skilled in the art to understand the present invention and design various embodiments with various modifications suitable for a particular purpose. Example

[0013] like Figures 1-2As shown, this embodiment provides a novel high-temperature and high-pressure resistant seamless steel pipe, including a pipe body 1. The pipe body 1 is an integrated seamless structure with a wall thickness of 5mm. The pipe body 1 is composed of a base layer 2, a high-temperature resistant layer 3, and a high-pressure resistant reinforcing layer 4. The base layer 2 is the substrate material layer, made of chromium-molybdenum-vanadium alloy steel. Its chemical composition, by mass percentage, is: Cr: 10%, Mo: 2%, V: 0.5%, C: 0.15%, Si: 0.2%, Mn: 0.5%, with the remainder being Fe and unavoidable impurities. The inner wall of the base layer 2 is provided with a spiral flow channel 5, the depth of which is 0.5mm and the pitch is 20mm. The flow channel 5 can reduce the erosion of the high-temperature resistant coating by the medium flow, while... To enhance the torsional resistance of the tube body 1, the high-temperature resistant layer 3 is a ceramic composite coating applied to the inner wall of the base layer 2 with a thickness of 0.1 mm. It is prepared using a plasma spraying process. The ceramic composite coating is an alumina-zirconia composite coating, in which the mass ratio of zirconia is 30%. The addition of zirconia can improve the high-temperature impact resistance of the coating and prevent the coating from cracking at high temperatures. The high-pressure resistant reinforcing layer 4 is a high-strength carbon fiber braided layer wrapped around the outer wall of the base layer 2 with a braiding density of 90%. The outer side of the carbon fiber braided layer is coated with a high-temperature resistant resin protective layer with a thickness of 0.2 mm. A spiral heat exchange tube 6 is wound around the outer surface of the tube body 1. A fixing cover 7 is installed at one end of the spiral heat exchange tube 6, and a fan 8 is installed inside the fixing cover 7. Example

[0014] Based on Example 1, and referring to Figure 2 As shown, the pipe body 1 is an integrated seamless structure with a wall thickness of 5mm-20mm. The pipe body 1 consists of a base layer 2, a high-temperature resistant layer 3, and a high-pressure resistant reinforcing layer 4. The base layer 2 is the substrate material layer, made of chromium-molybdenum-vanadium alloy steel. Its chemical composition, by mass percentage, is: Cr: 15%, Mo: 5%, V: 1.5%, C: 0.3%, Si: 0.6%, Mn: 1.2%, with the remainder being Fe and unavoidable impurities. The inner wall of the base layer 2 has spiral-shaped flow channels 5, with a depth of 1mm and a pitch of 50mm. The flow channels 5 reduce the impact of medium flow on the high-temperature resistant layer. The high-temperature coating enhances the torsional resistance of the pipe body 1. The high-temperature resistant layer 3 is a ceramic composite coating applied to the inner wall of the base layer 2 with a thickness of 0.3 mm. It is prepared by plasma spraying. The ceramic composite coating is an alumina-zirconia composite coating, in which the mass ratio of zirconia is 50%. The addition of zirconia can improve the high-temperature impact resistance of the coating and prevent the coating from cracking at high temperatures. The high-pressure resistant reinforcing layer 4 is a high-strength carbon fiber braided layer wrapped around the outer wall of the base layer 2 with a braiding density of 98%. The outer side of the carbon fiber braided layer is coated with a high-temperature resistant resin protective layer with a thickness of 0.4 mm.

[0015] The working principle of this utility model is as follows: Based on the integrated seamless chromium-molybdenum-vanadium alloy steel base layer 2, its specific chemical composition endows it with excellent mechanical strength. The spiral guide groove 5 on the inner wall can disperse the scouring of the medium and enhance the anti-torsion performance. The alumina-zirconia ceramic composite coating prepared by plasma spraying on the inner wall of the base layer 2 forms a high-temperature barrier, which improves thermal shock stability and avoids cracking. The high-density carbon fiber braided layer wrapped around the outer wall of the base layer 2 converts radial pressure into tensile stress to enhance high pressure resistance. The high-temperature resistant resin protective layer on the outer side ensures its stability. The auxiliary heat dissipation system composed of the spiral heat exchange tube and fan on the outside of the pipe body 1 reduces the overall temperature and alleviates the heat load through forced convection heat transfer. All structures work together from multiple dimensions such as load bearing, high temperature resistance, high pressure resistance, protection and heat dissipation to enable the steel pipe to achieve stable adaptation to high temperature and high pressure conditions.

[0016] Obviously, the described embodiments are only a part of the embodiments of this utility model, and not all of them. All other embodiments obtained by those skilled in the art and related fields based on the embodiments of this utility model without creative effort should fall within the protection scope of this utility model. Structures, devices, and operating methods not specifically described and explained in this utility model, unless otherwise specified or limited, shall be implemented according to conventional means in the art.

Claims

1. A novel high-temperature and high-pressure resistant seamless steel pipe, comprising a pipe body (1), characterized in that, The tube body (1) is an integrated seamless structure. The tube body (1) is composed of a base layer (2), a high temperature resistant layer (3) and a high pressure resistant reinforcing layer (4). The base layer (2) is the base material layer, which is made of chromium-molybdenum-vanadium alloy steel. Its chemical composition by mass percentage is: Cr: 10%-15%, Mo: 2%-5%, V: 0.5%-1.5%, C: 0.15%-0.3%, Si: 0.2%-0.6%, Mn: 0.5%-1.2%, and the remainder is Fe and unavoidable impurities. The inner wall of the base layer (2) is provided with a spiral guide groove (5). The depth of the guide groove (5) is 0.5mm-1mm and the pitch is 20mm-50mm. The high temperature resistant layer (3) is a ceramic composite coating applied to the inner wall of the base layer (2). The coating thickness is 0.1mm-0.3mm and it is prepared by plasma spraying. The high pressure resistant reinforcing layer (4) is a high-strength carbon fiber braided layer wrapped around the outer wall of the base layer (2). The braiding density is 90%-98%.

2. The novel high-temperature and high-pressure resistant seamless steel pipe according to claim 1, characterized in that, The wall thickness of the tube body (1) is 5mm-20mm.

3. The novel high-temperature and high-pressure resistant seamless steel pipe according to claim 1, characterized in that, The ceramic composite coating is an alumina-zirconia composite coating, wherein the mass percentage of zirconia is 30%-50%.

4. The novel high-temperature and high-pressure resistant seamless steel pipe according to claim 1, characterized in that, The outer side of the carbon fiber braided layer is coated with a high-temperature resistant resin protective layer with a thickness of 0.2mm-0.4mm.

5. A novel high-temperature and high-pressure resistant seamless steel pipe according to claim 1, characterized in that, The outer surface of the tube body (1) is wound with a spiral heat exchange tube (6), and a fixing cover (7) is installed at one end of the spiral heat exchange tube (6). A fan (8) is installed inside the fixing cover (7).

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