Exploring the Technologies and Applications of Steel Pipe Internal Coatings
Date:2025-09-10
Common Internal Coating Types and Technologies
Depending on the application scenario, internal coating materials and processes vary:
Epoxy resin coating: With its excellent adhesion, chemical resistance, and mechanical strength, it has become the mainstream choice in the oil, gas, and water sectors. Processes such as centrifugal spraying and high-pressure airless spraying form a dense protective film.
Polyurethane coating: With excellent wear resistance and flexibility, it is suitable for pipelines transporting highly abrasive media such as ores and slurries.
Cement mortar lining: Commonly used in water pipelines, it is low-cost and effectively prevents secondary water contamination. A uniform lining is formed through centrifugation.
Ceramic coating: It performs exceptionally well in extremely high-temperature and high-abrasion environments. Although costly, it is suitable for specific industrial applications.
Specialty coatings such as diepoxy and epoxy novolac are developed for high-temperature and highly corrosive environments to meet more stringent industrial requirements.
The application process of internal coatings is extremely critical, including surface preparation (typically requiring Sa2.5 rust removal standards), coating spraying, and curing. Negligence in any process can compromise the ultimate protective effect.
Wide Applications
Internal coating technology has penetrated multiple industrial sectors:
Oil and Gas Industry: From submarine pipelines to long-distance pipelines, internal coatings protect against corrosion from media such as H₂S, CO₂, and salt water, ensuring the safety of energy arteries.
Urban Water Systems: Internal coatings are applied to water pipelines and supply networks to effectively prevent corrosion and scale, improving water quality and network efficiency.
Chemical Industry: The transportation of corrosive chemicals such as acids, alkalis, and solvents relies on specialized coatings to protect pipelines and media purity.
Food and Pharmaceutical Industry: Safe coatings that comply with FDA standards ensure hygienic and pollution-free transportation.
Mining and Energy: Wear-resistant coatings are used on slurry and fly ash pipelines to reduce maintenance costs.
