2PE/3PE Anti-corrosion Steel Pipe

Epoxy powder-coated internal anti-corrosion steel pipe

Specifications: Φ89mm–Φ1820mm, Wall thickness: 6mm–20mm
Material: Q235B, Q345B, No. 10 Steel, No. 20 Steel, Grades X42–X80
2PE/3PE Anti-Corrosion Steel Pipe Standard: GB/T23257-2017
Epoxy Powder Internal Anti-Corrosion Steel Pipe Standard: SY/T0442-2010

2PE/3PE External Anti-Corrosion + Epoxy Powder Internal Anti-Corrosion Steel Pipe

2PE/3PE Anti-Corrosion Structure: An epoxy powder is electrostatically sprayed onto the surface of the steel pipe, followed by lateral wrapping with an adhesive and lateral wrapping with a polyethylene anti-corrosion layer. By combining the excellent properties of these three components, the overall quality of the anti-corrosion pipeline is significantly enhanced. This structure exhibits outstanding resistance to chemical corrosion, resistance to cathodic disbonding, and resistance to mechanical damage.

Before applying the anti-corrosion treatment, the base material of 2PE/3PE anti-corrosion steel pipes must undergo inspection and recording upon entering the pipe-handling platform. The outer surface of the steel pipe is then blast-cleaned to remove rust. Next, the cleanliness and anchor profile depth of the pipe’s outer surface are checked to ensure compliance with specified requirements. If any defects are found, they shall be carefully ground and repaired using a manual grinding wheel until they meet the standards. Afterward, adhesive tape is wrapped around the pipe ends, followed by dust removal. The pipe is then heated by medium-frequency induction to the required temperature, after which epoxy powder is sprayed onto its surface. Simultaneously, an adhesive extruder is used to apply adhesive along the side of the pipe, while a PE extruder is employed to perform the fusion coating on the opposite side. The anti-corrosion-coated pipe is subsequently cooled in water. Finally, qualified products are marked with identification labels, transferred to the pipe-handling platform, stacked, and prepared for shipment.

The applications of 3PE-coated steel pipes are extremely broad, making them suitable for various pipeline systems including underground water supply and drainage in coal mines, underground grouting, positive and negative pressure ventilation, gas extraction and drainage, fire-fighting sprinkling, and more. They are also ideal for conveying waste residues and return water in thermal power plants. These pipes exhibit outstanding performance when used as water supply lines in spray and sprinkler systems. Additionally, they serve as protective conduits for cables in power, telecommunications, and highway projects. They are widely used in high-rise building water supply systems, district heating networks, municipal water supply projects, gas transmission pipelines, and underground water pipelines. Furthermore, they are employed in process pipelines that convey corrosive media in industries such as oil transportation, chemical and pharmaceutical manufacturing, and textile dyeing. They are also utilized in wastewater treatment and discharge systems, sewage pipelines, and anti-corrosion projects for biological treatment ponds. Other applications include agricultural irrigation networks, deep-well pipes, drainage systems, and numerous other uses. It can be said that 3PE-coated steel pipes have become indispensable in today’s construction projects, and with the continued advancement of technology, we believe they will achieve even greater accomplishments in the future.

Fusion-bonded epoxy (FBE) powder coatings—also known as 2FBE—are a new type of anti-corrosion coating that has been developed over the past three decades. FBE coatings come in two types: single-layer and double-layer. The term "FBE coating" typically refers to the single-layer fusion-bonded epoxy coating. The single-layer FBE coating uses a specialized fusion-bonded epoxy powder coating as its film-forming material. This epoxy powder coating is applied via electrostatic spraying, forming a continuous film in a single pass. Such epoxy powder coatings are thermosetting materials, produced by mixing and grinding solid epoxy resins, curing agents, and various additives. Before painting, steel pipes undergo shot blasting and intermediate-frequency preheating. Then, using an electrostatic spraying method, the epoxy powder coating is applied onto the heated pipe surface, where it melts and bonds firmly to the pipe surface, subsequently curing to form a protective coating. Generally, FBE coatings have a single-coat film structure. FBE coatings offer numerous advantages, including strong adhesion to steel, excellent film integrity, resistance to cathodic disbondment, tolerance to soil stress and abrasion, simple application procedures, zero pollution, superior impact and flexural resistance, and high temperature resistance. As a result, they have been widely adopted abroad. FBE coatings can be used for external corrosion protection of steel underground pipelines or underwater pipeline facilities operating within a temperature range of -30°C to 100°C.