External corrosion is a primary concern for steel pipelines exposed to soil, moisture, chemicals, and mechanical stress during installation and operation. The choice of external coating is critical for protecting pipelines and ensuring long-term performance. Baolai Steel, a Chinese steel pipe manufacturer founded in 1991, is promoting its capabilities in supplying pipes with fusion-bonded epoxy (FBE), three-layer polyethylene (3LPE), and three-layer polypropylene (3LPP) coatings, among other solutions, for international projects.
According to the company, FBE forms a tightly bonded epoxy layer directly on prepared steel, providing a continuous corrosion barrier without a thick thermoplastic outer layer. This makes it suitable for many buried oil, gas, and water pipelines, especially where compatibility with cathodic protection is important. However, because single-layer FBE generally offers less resistance to mechanical damage than three-layer systems, careful handling during transportation and installation is necessary.
3LPE adds an adhesive layer and a polyethylene outer layer over the FBE corrosion barrier. This combination provides a bonded corrosion barrier plus additional resistance to moisture, impact, abrasion, and handling damage. For buried pipelines that will undergo transportation, trench installation, and backfilling, 3LPE is often considered when greater external protection is required than a single-layer FBE system provides.
3LPP follows a similar concept, using FBE as the corrosion barrier with an adhesive and polypropylene outer layer. Polypropylene is generally selected for higher service temperatures or more demanding mechanical conditions. It is therefore often considered for pipeline sections where the operating environment places greater thermal or mechanical demands on the external coating.
The company emphasizes that choosing between FBE, 3LPE, and 3LPP should be based on the complete service environment, not just coating type. Factors such as operating temperature, soil conditions, transportation and installation methods, mechanical damage risk, cathodic protection design, and project specifications must all be reviewed before finalizing the coating system. For exposed rather than buried piping, hot-dip galvanizing or painted finishes may be more appropriate.
Coating performance also depends on surface preparation, application control, specified thickness, inspection, and handling. Baolai Steel notes that purchase requirements should define more than just the coating type; buyers may need to specify applicable coating standards, required thickness, pipe-end cutback, inspection scope, repair requirements, and documentation. The company's quality control includes checking pipe surfaces before application, measuring coating thickness, visually examining the completed coating, and conducting holiday detection to identify discontinuities. Pipe-end conditions can be checked against order requirements, particularly for uncoated cutback areas needed for field welding. Repaired areas can be reinspected before shipment.
Baolai Steel combines steel pipe manufacturing with coating, secondary processing, inspection, and export support, allowing more stages of a coated-pipe order to be coordinated through one supply process. Processing options include beveling, threading, grooving, cutting, marking, bending, and galvanizing. With annual steel pipe production capacity of approximately 5 million tons, the company serves both distribution and project-based coated pipe requirements where specification control, coating quality, and coordinated delivery are important.
For industry leaders, this announcement underscores the importance of specifying the right coating system for pipeline projects to prevent corrosion failures, reduce maintenance costs, and extend asset life. As global energy infrastructure expands, the demand for reliable, high-performance coated pipes will continue to grow, making coordinated supply and rigorous quality control essential. For more information on Baolai Steel's coated pipe solutions, visit Baolai Steel.
