Armored optical cables are multi-layered fiber optic cables designed with protective metal armor to safeguard the fiber core from mechanical, environmental, and rodent damage while maintaining high transmission performance.

Core Structure

An armored optical cable typically consists of several layers from the inside out:

• Optical Fiber Core: The central component, usually single-mode or multi-mode fibers, responsible for transmitting data. Each fiber is coated with a buffer layer (commonly 900µm) for mechanical protection and flame resistance .

• Inner Protective Layer: Surrounds the fiber core and may include a plastic inner sheath and aramid yarn (Kevlar) to enhance tensile strength and prevent fiber stretching .

• Metal Armor Layer: The defining feature of armored cables, usually made of stainless steel, aluminum, or corrugated steel. This layer provides resistance against rodent bites, crushing, bending, and external impacts, ensuring durability in harsh environments .

• Outer Sheath: Typically made of polyethylene (PE) or polyvinyl chloride (PVC), the outer jacket protects against abrasion, UV radiation, moisture, and chemical exposure .

Types of Armor

Armored optical cables can feature different armor designs depending on application requirements:

• Single Armor: A single metal layer, often used for indoor patch cords or short runs .

• Double Armor: Combines a stainless steel hose with braided wire for enhanced protection, suitable for outdoor or high-risk installations .

• Square-Lock Armor: Square-profiled metal strips tightly wound around the cable, offering flexibility and bending resistance .

• Interlock Armor: Interlocking metal strips providing superior tensile strength and crush resistance, ideal for outdoor and industrial environments .

• Spiral Steel Armor: Helically wound steel tape for moderate protection with flexibility .

Advantages

Armored optical cables provide:

• Mechanical Protection: High resistance to compression, tension, and impact.
• Rodent and Pest Resistance: Metal armor prevents damage from animals.
• Environmental Durability: Resistant to moisture, UV, and chemical exposure.
• Installation Flexibility: Can be installed without conduit, pulled through ducts, floors, or outdoor routes .
• Stable Optical Performance: Armor does not affect signal quality, maintaining the same transmission performance as standard fiber .

Applications

Armored optical cables are widely used in:

• Outdoor and Industrial Environments: Direct burial, underground conduits, and harsh conditions.
• Telecom and Data Centers: High-traffic areas requiring robust protection.
• FTTH and Network Backbones: Long-distance transmission lines needing mechanical and environmental resilience . In summary, armored optical cables combine a fiber core with multiple protective layers, including metal armor and aramid reinforcement, to ensure durability, reliability, and long service life in challenging installation environments.