Steel strand for optical cables

Steel strand supported optical cables use a steel messenger or armored strand to provide mechanical support and durability for aerial fiber installations.

Structure and Design

Steel strand supported optical cables typically consist of optical fibers housed in loose tube or ribbon configurations, protected by water-blocking gels or materials. The fibers are supported by a steel messenger strand, which is a stranded steel cable that bears the weight of the fiber and provides tensile strength for aerial deployment. The steel strand often has zinc or zinc-aluminum coatings to prevent corrosion, with classes A, B, and C indicating increasing levels of protective coating.

Some designs include corrugated steel tape armor for additional mechanical protection against rodents and environmental hazards. Types and VariantsFigure-8 Self-Supporting Cables: These cables have a figure-8 shape with a central dielectric member and a steel messenger integrated into the design. They are suitable for aerial installations without additional support structures.

Metallic Aerial Self-

Supporting (MASS) Cables: These are compact, lightweight, all-metal cables designed for installation on medium and high-voltage power lines. They are self-supporting and minimize loading on towers while providing a telecommunications path.

Steel-

Stranded Dual-

Core Strain-Sensing Cables: These cables incorporate multiple metal reinforcing elements and a dual-core structure for redundancy or multiple measurements, enhancing mechanical robustness and surface strength.

Advantages

High Tensile Strength: Steel strands can support significant weight and withstand environmental loads such as wind and ice. Durability: Coated steel strands resist corrosion, extending the lifespan of aerial fiber networks, even in coastal or harsh environments. Flexibility for Expansion: Additional fiber cables can be lashed onto existing strands, allowing network upgrades without replacing the support structure.

Mechanical Protection: Armored designs protect fibers from physical damage, rodents, and environmental stress.

Installation Considerations

Steel strand supported optical cables are typically installed aerially, either as a messenger-supported cable or as a self-supporting figure-8 or MASS cable. Proper selection of strand diameter, coating, and cable type depends on span length, environmental conditions, and load requirements. Stainless steel lashing wires are often used to attach fibers to the messenger strand, providing flexibility and additional support.

Applications

These cables are widely used in telecommunications, utility networks, and long-span aerial fiber deployments, where mechanical strength, durability, and ease of expansion are critical. They are suitable for medium to high-voltage power line corridors, urban aerial networks, and coastal or corrosive environments.