1, Outdoor fiber optical cable mainly has the center tube cable, laminate cable and skeleton cable three kinds of structure, according to the use of optical fiber bundle and optical fiber belt and can be divided into ordinary optical cable and optical fiber belt cable and other 6 types. The structural characteristics of each optical cable:
(1) Central tube type fiber optical cable (YD/T769-2003) : the cable center is loose casing, strengthening components are located around the loose casing optical cable structure, such as the common GYXTW type optical cable and GYXTW53 type optical cable, the number of fiber core is small, usually for the following 12 core.
(2) Layer stranded cable (implementation standard: YD/T901-2001) : the strengthening member is located in the center of the cable, 5~12 loose tubes are twisted in the way of the core reinforcement, usually for SZ twisted. Such optical cables as GYTS can be combined with loose sleeves to obtain a larger number of fibers. In order to distinguish different loose tubes and different optical fibers, red and green lead chromatography is usually used for color separation of loose tubes with twisted layers. The number of fibers in the cable can be larger. At present, the number of fibers in the cable can reach 216 or higher.
(3) Skeleton type fiber optical cable: the strengthening member is located in the center of the optical cable, the skeleton groove composed of plastic on the strengthening member, optical fiber or optical fiber belt is located in the skeleton groove, optical fiber or optical fiber belt is not easy to press, the cable has good flattening resistance. This kind of fiber optic cable is rare in China, accounting for a small proportion.
(4) 8 type self-supporting structure, the structure of the cable can be incorporated into the center tube type and layer stranded cable, it is listed separately mainly because the optical cable structure and other cables have a great difference. There are usually center tube type and layer stranded type 8 self – supporting cable.
(5) Coal mine flame retardant fiber optical cable (implementation standard: Q/M01-2004 enterprise standard) : compared with ordinary optical cable, improve the flame retardant performance requirements of the optical cable, and through special design to make the optical cable suitable for use in the mine environment, usually the outer sheath color is blue, in order to facilitate the identification of optical cable in the mine. According to the structure can be divided into the center tube type cable and layer stranded cable two types of structure.
2, Indoor fiber optical cable
Indoor fiber optical cable is classified by fiber core number, mainly single core, double core and multi-core optical cable. Indoor optical cable is mainly composed of tightly set optical fiber, spinning fiber and PVC outer sheath. According to the type of optical fiber, the optical fiber can be divided into single-mode and multi-mode. The outer sheath color of single-mode indoor cable is usually yellow, the outer sheath color of multi-mode indoor cable is usually orange, and the outer sheath color of some indoor cable is gray.