Duct installation is a widely used method for fiber optic cable installation, which can provide extra protection for the optical cables. And as fiber optic cable is sensitive to excessive pulling, bending and crush forces, much care shall be taken to avoid cable damage during its duct installation. This post will give a detailed introduction to the duct installation of fiber optic cables.
Before introducing the duct cable installation, it is essential to have a knowledge of the commonly-used duct. Generally, the duct is often available in plastic, concrete, steel, iron and so on. And the plastic duct is one of the most popular ones for its advantages such as lightness, insulation and corrosion resistance. The following picture shows the details of a commonly-used plastic duct—seven-hole pipe.
Generally, the duct installation of fiber optic cable is a series of ducts placed under the streets, accessible by manholes. And the procedure of duct cable installation can be divided into duct placement and fiber cable placement. Thus, this part will focus on such factors as duct placement, manhole and fiber cable placement.
As mentioned above, the duct often buried under the street. And to avoid any damages to the duct, there are some attentions need to be paid when placing the duct. The following picture shows the right places that the duct shall be placed:
Another important factor during the duct placement is the pipeline. There are three kinds of pipelines the duct can be placed, which are gable-styled, line-styled and slant pipeline (as showing in the following figure):
The manhole is a hole through which a person can gain access to an underground structure. And it often equipped with a manhole cover. The following picture shows the inner structure of the manhole:
There are generally two methods for fiber optic cable placement: hand cable pulling and machine cable pulling. For short-distance placement of the cable, hand pulling is used; for long-distance placement, machine pulling is used.
The duct not only protects the fiber cable but also provides an opportunity for future cable access and expansion. Thus, the duct installation of fiber optic cable is a relatively cost-effective solution.