As we all know, we use the transmission medium of optical fiber for long-distance data transmission because it has the characteristics of reliable function, high quality, fast speed, low line loss and long transmission interval. Because it is a long-distance transmission, people generally require a safe operation period of 20 years or more for the cable on the land. The submarine cable system requires a higher safety period of more than 25 years.
Therefore, how to correctly use the optical cable in the cable routing, how to extend the life of the optical cable is a very concerned issue for the construction workers, let's talk about how to extend the life of the optical cable from the structure of the optical cable.
The three major factors affecting the life expectancy of optical fiber in optical cable: We all know that optical fiber is one of the most important components of optical cable. To improve the service life of optical cable, the most fundamental thing is to improve the service life of optical fiber. The main reasons affecting the service life of optical fiber are as follows: 1. The residual stress caused by unreasonable laying of optical cable is long-term; 2. The existence and expansion of micro-cracks on the appearance of optical fiber; 3. The water and water vapor molecules in the atmospheric environment. Etching of the exterior, etc. For the above reasons, the mechanical strength of the fiber with quartz glass as the base is gradually reduced, and the attenuation is gradually increased, eventually causing the fiber to crack and stopping the service life of the cable. Because there are always microcracks on the surface of the fiber, slow crack growth occurs in the atmosphere, causing the crack to expand continuously, and the mechanical strength of the fiber is gradually degraded.
Second, the method of extending the life of the fiber: when the fiber is in a vacuum environment, because there is no water molecule, there will be no stress erosion, the fatigue parameter n is the maximum value, and the fiber has the highest intensity. Strength is the inert strength of the fiber and is called Si. The application life ts of the optical fiber in the application environment is related to the stress σ it receives and the inert strength Si of the fiber: lgts=-nlgσ+lgB+(n-2)lgSi It is a constant, so when the stress σ is constant, the service life ts of the fiber is only related to the fatigue parameter n of the fiber. The larger the value of n, the longer the lifespan ts of the fiber. There are two ways to improve the life of the fiber: Method 1, improve the static fatigue parameter of the fiber to improve the life of the fiber. Therefore, when making optical fibers, people try to separate the quartz fiber itself from the atmospheric environment so that it is not affected by the atmospheric environment. By changing the value of n from the environmental data parameters to the parameters of the fiber data itself, it is possible to make The value of n becomes very large, thereby creating a "seal-covering skill" on the appearance of the fiber.
In the past decade, the use of "sealing and covering skills" to make optical fibers has made great progress. The coated data extends from metals to metal oxides, inorganic carbides, inorganic nitrides, carbides, nitrogen oxides, and CVD deposited amorphous carbon. The coating structure is developed from a single metal coating layer to a composite coating layer structure in which the sealing coating layer and the organic coating layer are combined, so that the optical fiber has more practical value, and the optical function, mechanical function and anti-wear function of the fiber are improved.
When the fatigue parameter n is punctured, the lifespan ts of the fiber is only related to the stress σ received. Therefore, reducing the stress on the fiber joint is a way to improve the service life of the fiber. When people make optical fibers, they form a compressive stress on the outer surface of the fiber to resist the tensile stress encountered, so that the tensile stress is reduced to the smallest extent possible, thereby generating compressive stress cladding skills to fabricate the fiber.
In summary, we can know that the process of making fiber optic cable pays attention to moisture and water resistance, and reduces the residual stress: each raw material of optical fiber cable must have more than 30 years of life and high stability physical function. Chemical function. As long as we strictly control the quality of each production process, we can extend the life of the cable.

How to extend the life of the fiber?