Page 47 - Market Analysis Report of Optical Communications Field in China & Global market 2019

Investigation on the structure and performance of the Flame-

retardant air-blowing micro optical cable

Li Wei, Fei Huaqing, Wang Rui, Zhou Feng, Zhou Zhihao, Sun Lihua,
Liu Peidong, Shi Huiping, Sheng Chuiming, Yin Jicheng
Hengtong Optic-electric Co., Ltd

Abstract
With the development of optical network, the deployment of optical fiber and cable has developed from the core trunk
line into MAN and AN, urban pipeline resources are becoming more and more tight, in order to make full use of this
precious resource, air-blowing installation has become the main construction method, air-blowing micro optical cable is
increasingly favored by customers.

The 5G wireless access network will adopt the C-RAN architecture, that is, the original BBU (baseband unit) of the base
station has been evolved the CU(centralized unit) and the DU (Distributed Unit), That is extended through the front end
and distributed in the streets and lanes, and the mountain village field. This means that a large amount of fiber needs to be
laid in 5G network, especially to be laid in between the Central Haul and the back Haul, the Flame-retardant air-blowing
micro optical cable is one of the most typical optical cable, which requires more and more indoor and outdoor deployment.
The flame-retardant air-blowing micro optical cable is widely favored by customers due to its light weight, easy laying,
high transmittance and the excellent characteristics of flame-retardant and air-blowing performance. In recent years, flame-
retardant air-blowing micro optical cable has shown rapid development and is widely used in large data center buildings
and other scenes. Flame-retardant performance has become a precondition that must comply with. In addition, Europe has
carried out CPR mandatory day on July 1, 2017; all optical cables through the buildings must pass CPR certification before
they can be applied.

Base the above background, This paper develops a kind of flame-retardant air-blowing micro optical cable. The specific
flame-retardant requirements of CPR are: CPR, s1a, d0, a1. In order to meet the mass production of flame-retardant air-
blowing micro optical cables, it is necessary to develop a stable production process. In this paper, the preparation process
and test performance of flame-retardant air-blowing micro optical cables are studied via from the aspects of cable structure
design, process control methods and material selection. Through the control of the plastic extrusion tooling process, the
design of the cable structure, the selection of the filling rod material and the outer sheath material, and the selection of the
thickness of the sheath, the effects of different schemes on the flame-retardant performance and air-blowing performance
of the cable are compared to determine the optimal solution, and finally the kind of flame-retardant air-blowing optical
cable has been developed, which comply the performance of CPR.

Key words: CPR, Cca, preparation process; flame-retardant performance; air-blowing performance; 5G

I ntroduction The Construction Products Regulation (CPR) stipulates

With the development of optical networks, the the cables that are permanently installed in buildings.
deployment of optical fiber and cable has developed At present, it is important to confirm the flame-
from the core trunk line into MAN and AN. In the last retardant performance of cables, and the fire- -resistance
1 km optical networks, optical cables require more and requirements are still being formulated. The flame-
more indoor and outdoor installations. In the process of retardant properties are divided into 7 grades – Class Aca,
network construction, due to the increasingly tight pipeline B1ca, B2ca, Cca, Dca, Eca, Fca. The test of CCa, s1a, d0,
resources, customers have put forward higher requirements a1 flame retardant performance include single vertical
on the space utilization of pipelines, the flame-retardant combustion, C-class beam combustion, smoke density, acid
performance of optical cables and the convenience of gas concentration and the test standard refers to EN13501-
maintenance. Based on the above application requirements, 6 cable product grade classification standard.
we have developed a kind of flame-retardant air-blowing
micro optical cable that has high transmittance and meets In this paper, the preparation process and test performance
the Cca grade of CPR. The micro optical cable uses LSZH of flame-retardant air-blowing micro optical cable are
material as the outer sheath material and is widely used in studied from the aspects of cable structure design, process
the laying of large data center buildings. control methods and material selection. By comparing

47