Metal loose tube optical cable

Metal loose tube optical cables are fiber optic cables with steel wire armoring and loose tube construction, designed for high-speed, long-distance communication with robust mechanical and environmental protection.Construction and Features

Metal loose tube optical cables typically consist of multiple loose tubes containing optical fibers, surrounded by water-blocking jelly to prevent moisture ingress. FRP (Fiber Reinforced Plastic) strength members enhance tensile strength, while steel wire armoring provides mechanical durability, rodent protection, and resistance to external impacts. The cables are usually sheathed with PE (polyethylene) inner and outer layers, offering UV resistance and suitability for direct burial or outdoor duct installation .

Advantages

• High mechanical strength: Steel wire armoring protects fibers from crushing and external forces.
• Moisture resistance: Water-blocking jelly and tape prevent water penetration, ensuring long-term reliability.
• Rodent protection: Armoring and sheaths reduce the risk of damage from animals.
• Long-distance transmission: Loose tube design allows for thermal expansion and contraction without stressing fibers, ideal for trunk lines, LANs, and distribution networks .
• Versatility: Suitable for both direct burial and duct installation, and can withstand harsh outdoor environments .

Applications

Metal loose tube optical cables are widely used in:

• Telecommunication backbones and trunk lines
• Local area networks (LANs) and distribution networks
• Industrial and outdoor installations where mechanical protection and environmental resistance are critical

Variants

Some cables may feature single-mode or multi-mode fibers, stranded or central tube designs, and varying fiber counts (e.g., 24 to 144 fibers). They are engineered to maintain performance across a wide temperature range and can include additional features like dielectric armoring for areas with high rodent risk . In summary, metal loose tube optical cables combine loose tube fiber protection with steel wire armoring, making them ideal for long-distance, high-speed data transmission in challenging environments while ensuring durability, moisture resistance, and ease of installation.