Steel strips for fiber optic cables

Steel strips in fiber optic cables serve as protective layers, providing mechanical strength, corrosion resistance, and long-term durability for both submarine and terrestrial applications.

Purpose and Function

Steel strips are used in fiber optic cables primarily to protect the delicate optical fibers from mechanical stress, environmental factors, and long-term wear. In submarine cables, stainless precision steel strips form shielding tubes around the optical fibers, embedding them in a protective gel to ensure stability during production, installation, and operation thousands of meters underwater (Waelzholz) . For terrestrial or underground cables, cold-rolled or galvanized steel strips provide tensile strength, corrosion resistance, and oxidation protection, safeguarding the fibers from moisture, physical impact, and other environmental hazards (GNEE Steel) .

Material Types

• Stainless Steel Strips: Used in high-end submarine cables, offering precise material properties, weldability, and forming characteristics. They protect fibers in deep-sea environments and maintain integrity during cable sheathing and laying processes .
• Cold-Rolled Steel Strips: Common in underground and communication cables, providing high tensile strength and corrosion resistance. Often coated or galvanized to enhance durability under varying environmental conditions .
• Galvanized Steel Strips: Applied in armored cables to prevent rust and extend service life, especially in humid, marine, or chemically aggressive environments .

Applications

• Submarine Fiber Optic Cables: Stainless steel strips form the inner protective tube, ensuring the optical fibers remain intact and functional over long distances under high pressure and harsh conditions .
• Armored Terrestrial Cables: Steel strips are used in spiral or longitudinal configurations to provide crush resistance, rodent protection, and mechanical strength. These are essential in industrial, railway, oil & gas, and direct-burial installations .
• Corrugated Steel Tape (CST) Armored Cables: Specialized steel strips are corrugated to enhance flexibility while maintaining protection, commonly used in outdoor and campus fiber optic networks .

Key Considerations

• Corrosion Resistance: Coatings or stainless steel selection is critical for long-term performance in wet or chemically aggressive environments .
• Mechanical Strength: Steel strips must withstand tensile, compressive, and impact forces during installation and operation .
• Compatibility with Cable Design: The steel strip must integrate with other layers, such as insulation, gel, and outer sheathing, without compromising fiber performance . In summary, fiber optic cable steel strips are essential for protecting optical fibers, ensuring reliable data transmission, and extending cable lifespan in both submarine and terrestrial applications. The choice of material—stainless, cold-rolled, or galvanized steel—depends on environmental conditions, mechanical requirements, and cable design specifications.