Fiber optic cables with metal strips, also known as metallic armored fiber optic cables, use steel or aluminum layers to protect optical fibers from mechanical damage, environmental stress, and rodent attacks.

Construction and Materials

Metallic armored fiber optic cables typically feature a central loose tube containing the optical fibers, often filled with a thixotropic gel for water blocking and long-term fiber protection. Around this core, a metal strip or armor layer—commonly corrugated steel tape (CST), steel wire armor (SWA), or interlocking aluminum—is applied to provide mechanical strength and resistance to crushing, impact, and rodent damage . The outer sheath is usually made of HDPE or PE, offering additional protection against UV radiation, chemicals, and temperature extremes . In submarine cables, stainless precision steel strips are used to shield fibers inside heavy-duty tubes, ensuring durability under deep-sea conditions .

Types of Armor

• Corrugated Steel Tape (CST): Provides high durability for direct burial and industrial applications, protecting against moisture, soil pressure, and mechanical impact .
• Steel Wire Armor (SWA): Offers superior tensile strength and crush resistance, suitable for outdoor and underground installations .
• Interlocking Aluminum Armor: Flexible and lightweight, ideal for installations requiring easier handling while still providing mechanical protection .

Applications

Metallic armored fiber optic cables are used in environments where mechanical protection and environmental resilience are critical:

• Underground telecom and railway signaling for short to medium distances .
• Industrial and energy facilities, including data centers and utility corridors .
• Submarine cables for transcontinental data transmission, where stainless steel strips shield fibers from deep-sea pressures .
• Aerial networks and duct systems, where cables may face vibration, accidental digging, or rodent attacks .

Advantages

• Mechanical Protection: Prevents fiber breakage from crushing, bending, or impact.
• Environmental Resistance: Shields fibers from moisture, chemicals, UV radiation, and temperature extremes.
• Rodent Protection: Metal armor deters chewing and damage from animals.
• Long-Term Reliability: Maintains optical performance under harsh conditions, ensuring uninterrupted data transmission . Metallic armored fiber optic cables are essential for mission-critical networks where durability, safety, and consistent data integrity are required, making them a preferred choice for both terrestrial and submarine installations.