What is Armored Fiber Optic Cable?

Armored fiber optic cable incorporates a metallic or non-metallic armor layer between the inner fiber core and the outer jacket, providing exceptional mechanical protection against crush, impact, rodent damage, and unauthorized access. The armor is typically a helical wrap of corrugated steel tape, stainless steel tube, aluminum tube, or non-metallic fiberglass yarn, depending on the application requirements. OMC manufactures armored cables with both single-mode and multimode fibers in counts from 2 to 288, suitable for direct burial, aerial installation, indoor/outdoor transitions, and industrial environments. Despite the added armor, these cables remain flexible enough for standard installation practices with appropriate cable handling tools.

Steel Tape Armor vs Stainless Steel Tube Armor

OMC offers two distinct armored cable constructions optimized for different environments. Corrugated steel tape armored cable (also called STA) features a longitudinally wrapped, corrugated steel tape bonded to the inner jacket, providing high crush resistance (typically 3000 N/10 cm) while maintaining good flexibility. It is the standard choice for direct burial in standard soils and indoor/outdoor routing where moderate mechanical protection is sufficient. Stainless steel tube armored cable uses a welded stainless steel tube encapsulating the fibers, providing the highest level of mechanical and rodent protection (crush resistance up to 5000 N/10 cm) along with longitudinal water blocking. This construction is preferred for direct burial in rocky terrain, rodent-prone areas, and submarine/underwater crossings where maximum durability is required.

Direct Burial Installation Best Practices

Armored cables designed for direct burial must be installed correctly to ensure long service life. Standard burial depth is 0.6 m to 1.2 m depending on local regulations and soil conditions. In rocky terrain, a sand bedding layer (75-100 mm) below and above the cable prevents point loading that could damage the armor over time. Warning tape should be placed 0.3 m above the cable to alert future excavation. For road or railway crossings, the armored cable should be routed through HDPE or PVC duct for additional protection and ease of future cable replacement. OMC's direct burial armored cables feature water-blocking tapes and yarns within the cable core to prevent longitudinal water ingress in case of jacket damage, providing decades of reliable service life in outdoor plant.

Aerial Installation with Figure-8 Self-Supporting Construction

For aerial installations between poles, OMC offers figure-8 self-supporting armored cable (GYTA53+steel messenger or GYFTCY) where the steel messenger wire is integrated into the jacket to support spans up to 80-100 meters between poles. The armored inner cable provides crush resistance during installation and long-term reliability against falling branches and ice loading. For longer spans or heavy-duty aerial deployments, ADSS (All-Dielectric Self-Supporting) cable can be combined with separate armor for hybrid applications. Installation tension must be calculated based on span length, ice and wind loading per local standards (NESC, ASCE 7), and the cable's specified maximum tension rating, typically 3000-5000 N for self-supporting armored constructions.

Ordering Information and Custom Configurations

To order OMC armored fiber optic cable, specify: fiber type and count (e.g., 24F G.652.D), armor construction (STA/SSA/aluminum/non-metallic), jacket material (PE/LSZH/AT), water-blocking requirements (dry core vs gel-filled), and installation method compatibility (direct burial/aerial/duct/indoor). Standard reels are 2 km to 4 km lengths, with custom reel lengths available for project-specific requirements. Each cable is tested 100% for fiber continuity, attenuation, and water-blocking integrity, with OTDR traces provided for documentation. OMC supports project-specific marking, sequential meter marking, and pre-connectorized armored assemblies for plug-and-play deployment. Contact our engineering team for site surveys, installation training, and OEM manufacturing agreements for telecommunications operators and network integrators.