First, the introduction of plastic-coated straight seam steel pipe
In simple terms, plastic-coated straight seam steel pipe is based on straight seam steel pipe, and a layer of plastic coating is applied on its inner and outer surfaces through a special process. Straight seam steel pipes may be familiar to everyone. Its weld is parallel to the axis of the steel pipe and has high strength and stability. And this layer of plastic coating is like putting a layer of strong and corrosion-resistant “protective clothing” on the steel pipe. This layer of coating is not applied casually. It has a strong adhesion to the steel pipe matrix and can fit together tightly and work together.
Second, the performance of plastic-coated straight seam steel pipe is “super god”
(I) Super corrosion resistance: Ordinary steel pipes are easily corroded and “full of holes” when encountering corrosive media such as acids, alkalis, and salts. But plastic-coated straight seam steel pipes are different. Its plastic coating is like an indestructible line of defense, completely isolating the steel pipe from the external corrosive medium. Whether it is the strong acid and alkali in industrial wastewater or the salt in the humid air in coastal areas, don’t think about breaking through this line of defense easily. This makes plastic-coated straight seam steel pipes very popular in industries such as chemical and sewage treatment, greatly extending the service life of the pipeline and reducing maintenance costs.
(ii) Strong wear resistance: In some scenarios where media containing solid particles are transported, such as slurry transportation in mines, the inner wall of the pipeline will be constantly eroded by particles and easily worn. The surface coating of plastic-coated straight seam steel pipes has a high hardness and can resist wear very well. Even under long-term and high-intensity particle erosion, it can maintain a good state and will not easily wear or perforate, which provides a strong guarantee for the continuity of production.
(iii) Excellent temperature resistance: Different engineering environments have different requirements for the temperature resistance of pipelines. Plastic-coated straight seam steel pipes can adapt to different temperature ranges depending on the plastic coating material selected. For example, epoxy resin coating can work normally in an environment of about -40℃ to 100℃; while polyethylene coating has stable performance at about -60℃ to 80℃. Whether in the cold north, the hot south, or the industrial scene where high-temperature media need to be transported, it can cope with it calmly and will not affect performance due to temperature problems.
(IV) Excellent hygienic performance: In some fields involving the transportation of drinking water, food, and beverages, the hygienic performance of the pipeline is extremely high. If the plastic-coated straight seam steel pipe uses a food-grade plastic coating, it will fully meet the hygienic standards. It is non-toxic and odorless, and will not cause any pollution to the transported medium, allowing us to use these resources with confidence. Therefore, in industries such as urban water supply and food processing, plastic-coated straight seam steel pipes have become the first choice.
(V) Low fluid resistance: Imagine that water flows on the rough inner wall of a pipe, just like a person walking on a rugged mountain road, the speed is definitely not fast. After the inner surface of the plastic-coated straight seam steel pipe is treated with plastic coating, it is very smooth and has extremely low roughness. This is like paving a flat highway for the fluid, allowing it to flow smoothly, greatly reducing the energy loss during transportation. In water supply and drainage projects, the use of plastic-coated straight seam steel pipes can improve the efficiency of water supply and drainage and save energy.
Third, plastic-coated straight seam steel pipes are widely used.
(I) Water supply and drainage projects: In urban water supply systems, plastic-coated straight seam steel pipes can ensure that the water quality is always clean and will not be polluted due to pipelines. Moreover, its corrosion resistance and long life also reduce the frequency of pipeline maintenance and replacement, ensuring the stability of urban water supply. In the drainage system, it can also easily cope with various corrosive substances in sewage, ensuring the smooth flow of drainage pipes and protecting the city’s “underground blood vessels”.
(II) Petrochemical industry: In the production process of petrochemicals, various highly corrosive chemical media are involved. With its excellent corrosion resistance, plastic-coated straight seam steel pipes have become the only choice for pipelines such as oil, natural gas, and chemical raw materials. It can safely and stably transport various media in complex and dangerous chemical environments, and has made great contributions to the normal operation of the petrochemical industry.
(III) Firefighting system: When a fire occurs, firefighting water must be able to be quickly and stably transported to the fire scene. Plastic coated straight seam steel pipe not only has good anti-corrosion performance, but also has high mechanical strength. It can withstand the high pressure of fire water, quickly transport water to where it is needed, buy precious time for fire fighting, and become an important line of defense to protect people’s lives and property.
(IV) Construction Engineering: Inside the building, plastic coated straight seam steel pipe can be used as a water supply and drainage pipe to meet the daily water needs of residents; it can also be used in air conditioning systems to transport circulating water; it can also serve as a heating pipe to bring warmth to everyone in winter. It meets the transportation needs of different fluids in the building and is an indispensable part of the construction project.
(V) Other fields: In addition to the above fields, plastic coated straight seam steel pipe is also widely used in mining, power, agricultural irrigation, and other fields. In mines, it is used to transport slurry; in the power industry, it is used to transport cooling water; in agricultural irrigation, it is used to transport irrigation water. It is like a silently dedicated “hidden master” and plays an important role in various fields.
Fourth, the production process of plastic-coated straight seam steel pipe
(I) Steel pipe pretreatment: Before plastic coating, straight seam steel pipes need to be strictly pretreated. First, the rust, oil, dust, and other impurities on the surface of the steel pipe should be thoroughly removed by shot blasting, sand blasting, and other methods. This is just like we have to wash our face before putting on makeup. Only in this way can the subsequent coating adhere better. After treatment, the surface of the steel pipe will reach a certain degree of roughness, laying a solid foundation for the firm combination of the coating and the steel pipe.
(ii) Plastic coating: There are many plastic coating processes, the most common ones are hot dip plastic and electrostatic spraying. Hot dip plastic is like giving the steel pipe a “plastic bath”, immersing the steel pipe in heated plastic powder or melt, so that the plastic is evenly coated on the surface of the steel pipe. Electrostatic spraying uses the principle of static electricity to make the plastic powder tightly adsorbed on the surface of the steel pipe like magic, and then heated and cured to form a solid coating.
(iii) Curing treatment: The steel pipe after plastic coating also needs to be cured. This step is like “forging” the coating to make it harder and denser. Through appropriate temperature and time control, the plastic coating is fully dried and cured, thereby improving the performance and quality of the coating, so that it can better play the role of protecting the steel pipe.
(IV) Quality inspection, strict control: The plastic-coated straight seam steel pipe produced cannot be shipped casually, and must undergo strict quality inspection. Carefully check the appearance to see whether the coating is uniform, whether there are defects such as bubbles and cracks; measure the thickness of the plastic coating layer to ensure that it meets the standards; test the bonding strength between the coating and the steel pipe through adhesion test; conduct corrosion resistance test to simulate the actual use environment to see how it performs in various corrosive media; and pressure test to test the performance of the pipeline under pressure. Only after passing these strict tests can the product be released and enter the market.
Fifth, you need to know these when choosing plastic-coated straight seam steel pipes.
(I) Clarify the needs and choose according to needs: Different projects have different performance requirements for plastic-coated straight seam steel pipes. For example, if you are using it to transport drinking water, you should focus on hygiene performance and choose products with food-grade coatings; if you are in the chemical industry, corrosion resistance is the primary consideration. Therefore, before choosing, you must clarify your needs and choose the right product according to the actual situation.
(ii) Investigate the manufacturer and pay attention to quality: There are many manufacturers producing plastic-coated straight seam steel pipes on the market, and the product quality is also uneven. When choosing a manufacturer, you should do more research to understand the manufacturer’s production process, quality control system, reputation, etc. You can check the manufacturer’s relevant qualification certificates and visit the production workshop to see the actual production situation. Only by choosing a strong and reputable manufacturer can you guarantee the quality of the product and after-sales service.
(iii) Reasonable price, cost-effectiveness first: Price is a factor that everyone will consider when choosing a product. But when choosing plastic-coated straight seam steel pipes, you can’t just look at the cheap price and ignore the quality. It is necessary to comprehensively consider the performance, quality, and price of the product and choose a product with high cost-effectiveness. After all, although the price of a good quality product may be higher, it is more cost-effective in terms of long-term use and maintenance costs.
Post time: Jul-02-2025