Drawing of High-Strength Long-Length Optical Fibers for Submarine Cables

A drawing process for high-strength long-length optical fibers intended for submarine cables was developed using a carbon resistance furnace. Surface treatment conditions for preforms as well as drawing furnace cleanliness for minimizing flaw formations on the fibers during the drawing process are described. Furthermore, an evaluation of the mechanical performance of long fibers is discussed on the basis of the fracture mechanics concept. Nonbreak stress conditions for optical fibers subjected to static loading are also described.