A corrosion-resistant, durable, seamless steel pipe

Abstract

The utility model relates to a seamless steel pipe technical field, a kind of anticorrosive durable seamless steel pipe, including seamless steel pipe, the outer surface of seamless steel pipe is sequentially provided with bottom layer reinforcing attachment layer, intermediate composite anticorrosive layer, buffer transition layer and surface layer wear-resistant protective layer, the utility model sequentially sets up bottom layer reinforcing attachment layer, intermediate composite anticorrosive layer, buffer transition layer and surface layer wear-resistant protective layer on the outer surface of the seamless steel pipe, solve the problem that ordinary anticorrosive layer adhesion is poor, bottom layer reinforcing attachment layer can avoid the peeling of anticorrosive layer due to salt erosion etc., simultaneously, intermediate composite anticorrosive layer overcomes the single drawback of anticorrosive performance, can adapt to high temperature and high pressure, strong acid and strong base and other complex harsh environment, effectively resist a variety of corrosion factors, reduce steel pipe corrosion, reduce the cost brought by frequent replacement of steel pipe, can satisfy the demand of seamless steel pipe long-term stable operation under various working conditions.

Description

Technical Field

[0001] This utility model relates to the field of seamless steel pipe technology, and in particular to a corrosion-resistant and durable seamless steel pipe. Background Technology

[0002] Seamless steel pipes are made by piercing a single round steel bar, resulting in a hollow cross-section without weld seams. Based on production methods, they can be classified as hot-rolled, cold-rolled, and cold-drawn types. According to their applications, they include structural pipes, fluid transport pipes, and boiler tubes. They are high-strength and resistant to high pressure, widely used in petroleum, chemical, machinery manufacturing, and construction industries, and are an important economical steel material.

[0003] To improve the corrosion resistance of seamless steel pipes, an anti-corrosion layer is usually installed on their outer side. However, the anti-corrosion layers currently in use have many problems. For example, in some coastal chemical projects, the adhesion between the anti-corrosion layer and the steel pipe substrate of ordinary anti-corrosion seamless steel pipes is poor. After the project has been in operation for a period of time, due to the salt erosion brought by the sea breeze and the slight leakage of chemical raw materials, the chloride ions and other highly corrosive substances in the salt will destroy the bonding interface between the anti-corrosion layer and the steel pipe substrate, resulting in the peeling of the anti-corrosion layer.

[0004] At the same time, the anti-corrosion performance of this type of anti-corrosion layer is too singular, and it can only cope with a certain specific corrosive environment. When it is in a complex and harsh environment such as high temperature and high pressure, strong acid and strong alkali, just like in some high temperature and high pressure oil refining equipment, the anti-corrosion layer will quickly lose its effectiveness and cannot effectively resist the invasion of multiple corrosive factors. This not only aggravates the corrosion of steel pipes, but also leads to frequent replacement of steel pipes, increasing costs, and it simply cannot meet the requirements for long-term stable operation under various working conditions. Utility Model Content

[0005] This utility model addresses the shortcomings of existing technologies by providing the following technical solution: a corrosion-resistant and durable seamless steel pipe, comprising a seamless steel pipe, wherein the outer surface of the seamless steel pipe is sequentially provided with a bottom reinforcing adhesion layer, an intermediate composite anti-corrosion layer, a buffer transition layer and a surface wear-resistant protective layer;

[0006] The underlying reinforcement layer is directly attached to the outer surface of the seamless steel pipe to enhance the adhesion between the subsequent coating and the seamless steel pipe.

[0007] The intermediate composite anti-corrosion layer is located outside the bottom reinforcing adhesion layer and is used to resist the erosion of various chemical media.

[0008] The buffer transition layer is disposed between the intermediate composite anti-corrosion layer and the surface wear-resistant protective layer;

[0009] The surface wear-resistant protective layer is wrapped around the outside of the buffer transition layer.

[0010] As an improvement to the above technical solution, the underlying reinforcing adhesion layer is a coating formed by spraying nano-ceramic coating after treatment with a silane coupling agent.

[0011] As an improvement to the above technical solution, the intermediate composite anti-corrosion layer is composed of epoxy resin glass flake coating and polyurethane elastomer.

[0012] As an improvement to the above technical solution, the buffer transition layer is made of rubber elastomer material.

[0013] As an improvement to the above technical solution, the surface wear-resistant protective layer is a fluorocarbon resin coating spray layer.

[0014] As an improvement to the above technical solution, in the underlying reinforcing adhesion layer, when treated with silane coupling agent, the concentration of silane coupling agent is controlled at 0.5%-2%, and the coating thickness formed by spraying nano-ceramic coating is 20-50μm.

[0015] As an improvement to the above technical solution, in the intermediate composite anti-corrosion layer, the composite volume ratio of epoxy resin glass flake coating and polyurethane elastomer is 1:0.8-1:1.2, and the total thickness of the intermediate composite anti-corrosion layer is 100-200μm.

[0016] The beneficial effects of this utility model are as follows: The outer surface of the seamless steel pipe is sequentially provided with a bottom reinforcing adhesion layer, an intermediate composite anti-corrosion layer, a buffer transition layer, and a surface wear-resistant protective layer. This solves the problem of poor adhesion of ordinary anti-corrosion layers. The bottom reinforcing adhesion layer can prevent the anti-corrosion layer from peeling off due to salt corrosion, etc. At the same time, the intermediate composite anti-corrosion layer overcomes the shortcomings of single anti-corrosion performance, can adapt to complex and harsh environments such as high temperature and high pressure, strong acid and strong alkali, effectively resist various corrosive factors, reduce steel pipe corrosion, reduce the cost of frequent steel pipe replacement, and can meet the needs of seamless steel pipe for long-term stable operation under various working conditions. Attached Figure Description

[0017] Figure 1 This is the main view of the corrosion-resistant and durable seamless steel pipe of this utility model;

[0018] Figure 2 This is a cross-sectional view of the internal structure of this utility model;

[0019] Figure 3 This utility model Figure 2 Enlarged view of the structure at point A in the middle.

[0020] Reference numerals: 1. Seamless steel pipe; 2. Underlying reinforcing adhesion layer; 21. Silane coupling agent; 22. Nano-ceramic coating; 3. Intermediate composite anti-corrosion layer; 31. Epoxy resin glass flake coating; 32. Polyurethane elastomer; 4. Buffer transition layer; 41. Rubber elastomer material; 5. Surface wear-resistant protective layer; 51. Fluorocarbon resin coating. Detailed Implementation

[0021] To make the objectives, technical solutions, and advantages of this utility model clearer, the following provides a more detailed description of the utility model. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of the utility model.

[0022] Please see Figure 1-3 This utility model provides a technical solution: a corrosion-resistant and durable seamless steel pipe, including a seamless steel pipe 1. The outer surface of the seamless steel pipe 1 is sequentially provided with a bottom reinforcing adhesion layer 2, an intermediate composite anti-corrosion layer 3, a buffer transition layer 4 and a surface wear-resistant protective layer 5. The layers are tightly bonded together through specific process treatment to form an organic overall protection system.

[0023] The bottom reinforcing adhesion layer 2 is directly attached to the outer surface of the seamless steel pipe 1. Its function is to enhance the adhesion between the subsequent coating and the seamless steel pipe 1 and prevent the coating from falling off during use.

[0024] The intermediate composite anti-corrosion layer 3 is located above the bottom reinforced adhesion layer 2 and is the core anti-corrosion part of the entire protection system. It can effectively resist the erosion of various chemical media and prevent the seamless steel pipe 1 from experiencing performance degradation and shortened service life due to corrosion.

[0025] The buffer transition layer 4 is set between the intermediate composite anti-corrosion layer 3 and the surface wear-resistant protective layer 5, which plays a role in buffering stress and reducing the risk of interlayer peeling.

[0026] The surface wear-resistant protective layer 5 is wrapped around the outside of the buffer transition layer 4 and is directly exposed to the external environment, bearing various physical effects such as mechanical wear and scratches.

[0027] As an improvement to the above technical solution, the bottom reinforcing adhesion layer 2 is a coating formed by spraying nano-ceramic coating 22 after treatment with silane coupling agent 21.

[0028] In this embodiment, the outer surface of the seamless steel pipe 1 is sequentially provided with a bottom reinforcing adhesion layer 2, an intermediate composite anti-corrosion layer 3, a buffer transition layer 4, and a surface wear-resistant protective layer 5. This solves the problem of poor adhesion of ordinary anti-corrosion layers. The bottom reinforcing adhesion layer 2 can prevent the anti-corrosion layer from peeling off due to salt corrosion, etc. At the same time, the intermediate composite anti-corrosion layer 3 overcomes the drawback of single anti-corrosion performance, can adapt to complex and harsh environments such as high temperature and high pressure, strong acid and strong alkali, effectively resist various corrosive factors, reduce steel pipe corrosion, reduce the cost of frequent steel pipe replacement, and can meet the needs of long-term stable operation of the seamless steel pipe 1 under various working conditions.

[0029] Specifically, the bottom reinforcing adhesion layer 2 is a coating formed by spraying nano-ceramic coating 22 after treatment with silane coupling agent 21.

[0030] In this embodiment, the bottom reinforcing adhesion layer 2 significantly enhances its adhesion to the seamless steel pipe 1 through the chemical bonding of the silane coupling agent 21 and the filling effect of the nano-ceramic coating 22, effectively preventing the anti-corrosion layer from peeling off during use.

[0031] Specifically, the intermediate composite anti-corrosion layer 3 is composed of epoxy resin glass flake coating 31 and polyurethane elastomer 32.

[0032] In this embodiment, the intermediate composite anti-corrosion layer 3 combines the chemical corrosion resistance of epoxy resin glass flake coating 31 with the flexibility of polyurethane elastomer 32, which can resist the invasion of multiple corrosive factors at the same time and adapt to complex and harsh environments such as high temperature, high pressure, strong acid and strong alkali.

[0033] Specifically, the buffer transition layer 4 is made of rubber elastomer material 41.

[0034] In this embodiment, the buffer transition layer 4 is made of rubber elastomer material 41, which can effectively buffer external impact, disperse stress, prevent the intermediate composite anti-corrosion layer 3 from cracking, and at the same time enhance the bonding strength between the surface wear-resistant protective layer 5 and the intermediate composite anti-corrosion layer 3.

[0035] Specifically, the surface wear-resistant protective layer 5 is a fluorocarbon resin coating 51 spray layer.

[0036] In this embodiment, the fluorocarbon resin coating 51 of the surface wear-resistant protective layer 5 has excellent wear resistance and weather resistance, which reduces the wear and aging rate of the pipeline during operation and extends the service life of the pipeline.

[0037] Specifically, in the bottom reinforcing adhesion layer 2, when treated with silane coupling agent 21, the concentration of silane coupling agent 21 is controlled at 0.5%-2%, and the coating thickness formed by spraying nano-ceramic coating 22 is 20-50μm.

[0038] In this embodiment, the underlying reinforcing layer 2 is ensured to have good adhesion to the surface of the seamless steel pipe 1 while maintaining its performance stability.

[0039] Specifically, in the intermediate composite anti-corrosion layer 3, the composite volume ratio of epoxy resin glass flake coating 31 and polyurethane elastomer 32 is 1:0.8-1:1.2, and the total thickness of the intermediate composite anti-corrosion layer 3 is 100-200μm.

[0040] In this embodiment, the ratio and thickness range enable the intermediate composite anti-corrosion layer 3 to possess both excellent anti-corrosion performance and a certain degree of flexibility.

[0041] The process flow is as follows;

[0042] (I) Pretreatment of Seamless Steel Pipes

[0043] Seamless steel pipe 1, which meets national standards, is selected and its surface is treated. First, sandblasting is used to remove rust, scale and other impurities from the surface of the steel pipe, so that the surface reaches the Sa2.5 level rust removal standard. Then, silane coupling agent 21 is used to treat the surface of the steel pipe. The silane coupling agent 21 is prepared into a solution of a certain concentration and is evenly covered on the surface of the seamless steel pipe 1 by spraying or dipping. After treatment, it is dried in a dry and ventilated environment to provide a good foundation for subsequent coating.

[0044] (II) Coating of the bottom reinforcing adhesion layer 2

[0045] The nano-ceramic coating 22 is mixed in the specified proportion and stirred evenly. Then, the coating is evenly sprayed onto the surface of the pretreated seamless steel pipe 1 using a high-pressure airless spraying device. The spraying pressure and speed are controlled to ensure that the thickness of the bottom reinforcing adhesion layer 2 is uniform and consistent, reaching the requirement of 15-30μm. After spraying, the steel pipe is placed in a dry and ventilated environment for natural curing. The curing time is determined according to the ambient temperature and coating performance, generally 24-48 hours.

[0046] (III) Laying of intermediate composite anti-corrosion layer 3

[0047] After the bottom reinforcing layer 2 has cured, epoxy resin glass flake coating 31 is first sprayed using air spraying or airless spraying to ensure that the coating is evenly covered on the bottom reinforcing layer 2. Then, polyurethane elastomer 32 is immediately sprayed onto the surface of epoxy resin glass flake coating 31. By adjusting the spraying parameters, the polyurethane elastomer 32 and epoxy resin glass flake coating 31 are fully mixed to form an intermediate composite anti-corrosion layer 3 with a thickness of 0.8-1.5mm. After the intermediate composite anti-corrosion layer 3 is laid, it is cured at room temperature for 48-72 hours.

[0048] (iv) Setting up the buffer transition layer 4

[0049] After the intermediate composite anti-corrosion layer 3 is cured, the rubber elastomer material 41 is evenly applied to the surface of the intermediate composite anti-corrosion layer 3, and the coating thickness is controlled to be 50-80μm. It can be applied by scraping or spraying to ensure that the buffer transition layer is evenly and smoothly covered on the intermediate composite anti-corrosion layer 3. After the coating is completed, it is dried at room temperature to allow the rubber elastomer material 41 to be initially cured.

[0050] (V) Surface Abrasion-Resistant Protective Layer 5 Coating

[0051] After the buffer transition layer 4 is dried, fluorocarbon resin powder is uniformly sprayed onto the surface of the buffer transition layer 4 using an electrostatic spraying process. Electrostatic spraying allows the fluorocarbon resin powder to be better adsorbed onto the buffer transition layer 4, forming a uniform and dense coating. The spraying parameters are controlled to ensure that the thickness of the surface wear-resistant protective layer 5 reaches 80-120μm. After spraying, the steel pipe is placed in a high-temperature curing oven for sintering and curing. The curing temperature is 220-250℃ and the curing time is 10-15 minutes. After curing, the steel pipe is allowed to cool naturally to room temperature.

[0052] The above embodiments are only used to illustrate the technical solution of this utility model, and are not intended to limit it.

Claims

1. A corrosion-resistant and durable seamless steel pipe, comprising a seamless steel pipe (1), characterized in that: The outer surface of the seamless steel pipe (1) is sequentially provided with a bottom reinforcing adhesion layer (2), an intermediate composite anti-corrosion layer (3), a buffer transition layer (4), and a surface wear-resistant protective layer (5); The bottom reinforcing adhesion layer (2) is directly attached to the outer surface of the seamless steel pipe (1) to enhance the adhesion between the subsequent coating and the seamless steel pipe (1); The intermediate composite anti-corrosion layer (3) is located outside the bottom reinforced adhesion layer (2) and is used to resist the erosion of various chemical media. The buffer transition layer (4) is disposed between the intermediate composite anti-corrosion layer (3) and the surface wear-resistant protective layer (5); The surface wear-resistant protective layer (5) is wrapped around the outside of the buffer transition layer (4).

2. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: The bottom reinforcing adhesion layer (2) is a coating formed by spraying nano-ceramic coating (22) after treatment with silane coupling agent (21).

3. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: The intermediate composite anti-corrosion layer (3) is composed of epoxy resin glass flake coating (31) and polyurethane elastomer (32).

4. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: The buffer transition layer (4) is made of rubber elastomer material (41).

5. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: The surface wear-resistant protective layer (5) is a fluorocarbon resin coating (51) spray layer.

6. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: In the bottom reinforcement adhesion layer (2), when treated with silane coupling agent (21), the concentration of silane coupling agent (21) is controlled at 0.5%-2%, and the coating thickness formed by spraying nano-ceramic coating (22) is 20-50μm.

7. The corrosion-resistant and durable seamless steel pipe according to claim 1, characterized in that: In the intermediate composite anti-corrosion layer (3), the composite volume ratio of epoxy resin glass flake coating (31) and polyurethane elastomer (32) is 1:0.8-1:1.2, and the total thickness of the intermediate composite anti-corrosion layer (3) is 100-200μm.

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