How can we achieve metal protection while still allowing it to be coiled and wound like a regular rope?
“Flexible Armoring” refers to an engineering encapsulation structure that maintains high tensile, crush resistance, and anti-rodent mechanical protection performance while imbuing fiber optic cables or sensing cables with excellent flexibility and coiling ability, similar to ordinary soft ropes.
The engineering physics principles for achieving “both metal protection and coiling ability like an ordinary rope” primarily include the following core elements:
1. Micro Seamless Steel Tube Structure
According to the principles of material mechanics, the stress in a tube during bending is directly related to its outer diameter and wall thickness. When the outer diameter of the metal tube is reduced to an extremely small level (e.g., an outer diameter of only 0.6\text{mm} to 1.0\text{mm} ), its bending stiffness is significantly reduced, allowing for a very small permissible bending radius. Simultaneously, the seamless round tube structure can uniformly withstand lateral pressure from all sides, providing extremely high compressive strength (e.g., compressive strength can reach > 200\text{MPa} ).
2. Multi-strand Micro Steel Wire Braiding/Rope Structure
Outside the inner micro metal tube, multiple strands of extremely fine stainless steel wires (such as fine steel wires with a diameter of 0.45\text{mm} or 0.6\text{mm} ) are helically twisted or braided. A single fine steel wire has very low bending stiffness, so when multiple strands are twisted together, they can bend and coil freely like a steel wire rope; when subjected to tensile force, the multiple strands bear the load cooperatively, providing strong tensile performance (tensile strength can reach > 1200\text{N} ).
3. Bending-Insensitive Fiber Core
The internal fiber typically uses bending-insensitive single-mode fiber conforming to the G.657 standard. Compared to traditional fibers, bending-insensitive fibers optimize the core refractive index profile, allowing the optical signal to maintain extremely low additional bending loss even when coiled with a small bending radius.
OFSCN® Flexible Armoring Products
Based on the micro steel tube and steel wire rope twisting structure described above, OFSCN® has developed several flexible armored fiber optic patch cord products:
1. OFSCN® 2.0mm Micro Steel Armored Fiber Optic Patch Cord
This product consists of a fiber connector, PVC jacket, 0.6\text{mm} stainless steel seamless steel tube, and fiber optic cable. The default diameter is 2\text{mm}, with a tensile strength of > 150\text{N} and compressive strength of > 240\text{MPa}, combining a micro outer diameter with flexible bending characteristics.
2. OFSCN® 2.0mm Steel Wire Rope Fiber Optic Patch Cord
This product consists of a fiber connector, a 0.6\text{mm} galvanized steel wire rope structure, a 1.0\text{mm} stainless steel seamless steel tube, and fiber optic cable. It features a full metal structure encapsulation, providing extremely high mechanical durability and flexibility.
3. OFSCN® 3.0mm Steel Wire Rope Fiber Optic Patch Cord
This product consists of a fiber connector, PE jacket, 0.45\text{mm} stainless steel wire rope structure, 0.9\text{mm} stainless steel seamless steel tube, and G.657 bending-insensitive fiber. With a tensile strength of > 1200\text{N} and compressive strength of > 200\text{MPa}, it can be coiled and looped like a rope while withstanding high tensile forces and heavy pressure.
