What are Fire-Fighting Coated Steel Pipes

Fire-fighting plastic-coated steel pipes are specialized steel-plastic composite pipes for fire sprinkler and fire hydrant systems. Using straight seam welded pipes, seamless steel pipes, or spiral steel pipes as the base material, they undergo sandblasting to remove rust and preheating. The inner and outer walls are then coated with flame-retardant modified epoxy resin (EP) powder at high temperatures and cured. The outer wall is uniformly a striking red (fire-fighting identification color). This product perfectly combines the mechanical strength of steel pipes with the corrosion resistance, flame retardancy, and smooth water delivery advantages of plastic, making it an upgraded replacement for traditional hot-dip galvanized fire-fighting pipes.

Base Pipe Pretreatment: Steel pipes are cut to length and sandblasted to Sa2.5 grade to thoroughly remove oxide scale and oil stains;
High-Temperature Preheating: The entire pipe is heated to the appropriate temperature for powder melting;
Internal and External Electrostatic Spraying: Flame-retardant epoxy powder is simultaneously sprayed onto the inner and outer walls;
High-Temperature Curing and Baking: The powder cross-links to form a dense, seamless anti-corrosion film;
End Processing: Grooving, threading, and flange beveling;
Finished Product Inspection: Spark leak detection, coating thickness inspection, water pressure resistance test, and adhesion impact test.

Q235B straight seam ERW welded pipe, 20# seamless steel pipe, Q355 spiral welded pipe, with a maximum pressure resistance of 2.5MPa, meeting the requirements of high-pressure water supply for fire protection.

Coating thickness: Inner wall 300~400μm, outer wall 400~800μm; Contains a flame-retardant formula, does not burn at high temperatures, does not soften or peel off, and complies with fire-fighting flame-retardant standards; Food-grade inner wall, does not leach harmful substances, and does not pollute water quality during long-term water storage.

DN50～DN1200, mainstream for indoor sprinklers DN65~DN300; large-diameter spiral coated pipes are used for large underground pipe galleries and municipal fire protection trunk lines.

Standard bright red outer wall, the industry-standard fire warning color, facilitating the differentiation between water supply and drainage and gas pipelines during fire protection engineering acceptance.

The epoxy coating completely isolates water, oxygen, and soil acids, alkalis, and salts, preventing rust and scale buildup even when buried underground, in damp basements, or in chemical workshops; ordinary galvanized pipes rust and produce yellow water that clogs sprinkler heads within 8-15 years.

The mirror-smooth inner wall reduces hydraulic resistance by 30% compared to galvanized pipes, preventing rust and scale buildup, eliminating sprinkler head clogging and ensuring stable water supply during fires.

The coating contains a special flame retardant, preventing self-ignition upon contact with open flames and ensuring the coating does not peel off. The pipe structure remains stable under high temperatures, meeting mandatory requirements of building fire safety codes.

Mainstream grooved clamp connection (installation speed 3 times faster than welding), also supports threaded, flanged, and bimetallic welding, eliminating the need for professional welders, significantly shortening fire protection construction time, and is earthquake-resistant and adaptable to minor foundation settlement.

It can withstand high-expansion foam for fire fighting and resists long-term erosion by solvent extinguishing agents. It is specially designed for fire protection systems in chemical industrial parks and oil depots.

Grooved (Clamp) Connection: DN65~DN400, preferred for indoor sprinkler and fire hydrant systems, easy to install and disassemble, and earthquake-resistant;

Threaded Connection: DN50 and below for small branch pipes;

Flanged Connection: Large-diameter main pipelines and pump room equipment connections;

Bimetallic Welding: Long-distance buried pipelines, with a protective coating applied after welding.

Indoor Fire Protection in Buildings: Automatic sprinkler systems in high-rise commercial buildings, office buildings, and residences; indoor fire hydrant networks;

Underground Engineering: Underground parking garages, integrated utility tunnels, and buried fire protection pipelines in civil defense projects;

Special Industrial Plants: Fire protection pipelines in corrosive environments such as chemical industrial parks, oil depots, pharmaceutical factories, and electroplating workshops;

Municipal Outdoor Fire Protection: Main fire-fighting arteries on urban roads and outdoor fire hydrant networks in industrial parks;

Fire water supply systems for ships, ports, and tunnels.

Comparison Item	Fire-Rated Epoxy Plastic Coated Steel Pipe	Traditional Hot-Dip Galvanized Steel Pipe
Anti-Corrosion Service Life	Over 50 years, minimal maintenance required	Only 8–15 years, regular rust removal and repairs necessary
Inner Wall Scaling & Sprinkler Clogging Risk	Smooth lining, zero rust buildup, no sprinkler blockage	Prone to rust and limescale accumulation, high risk of sprinkler clogging
Flame Retardant Performance	Special flame-retardant epoxy coating designed for fire service	Zinc coating easily oxidizes and peels off under high temperatures
Water Quality Impact	No rusty water, no water contamination	Rust generates brown sediment and pollutes water medium
Underground Installation Compatibility	Resistant to acidic & alkaline soil, suitable for long-term underground burial	Vulnerable to soil corrosion; leakage and rust appear within 3–5 years underground
Total Long-Term Operating Cost	Slightly higher upfront cost, nearly zero maintenance expense later	Low initial purchase price, high recurring replacement and repair costs over service life

We supply fire protection red epoxy plastic coated steel pipes based on ERW seamless and SSAW spiral substrates, complying with GB/T5135.20, NFPA13 and EN standards with complete fire inspection reports and CE certification. Available in grooved, threaded and flanged ends for fire sprinkler and hydrant systems.