OPTICAL FIBER CABLE
The number of fibers in a cable varies from 4 to 96 (more number of fibers are provided upon request). OPtical fiber cables will generally undergo 4 processes of production line such as Coloring Line, Secondary Coating Line, SZ-Stranding Line and Sheathing Line.
Coloring Production Line:
Fiber coloring Process is carried out to mark the fiber. For easy identification of insdividual fiber inside the tubes, they are color coded. The colors have no influence. on the optical properties of the fibers. The fibers are colored using UV curable ink which are chosen as industry standard, easily in stripping, jointing and stability of optical loss under various stress.
Secondary Coating Production Line:
This process uses Polybutylene Terepthalate (PBTP) as tube material which extremely has good thermal, hidrolysis and mechanical properties. The tube contain fibers and are filled with special typical gel. Secondary coating or tubing process is used to protect the optical fibers during cabling and installation process.
SZ-Stranding Production Line:
Stranding process which is around polyethylene coated central strength member applies SZ-Stranding Method. The stranding is filled with jelly as flooding Compound to fill any space of the block the flow of the water into the cable.
Sheathing Production Line:
Sheathing line is an unit which its process protects the optical cable core from mechanical, thermal and chemical effects, associated with storage, installation and operation. The core covering is covered with the laminated Aluminium Polyethylene (LAP) sheath containing carbon black, to provide an electrical ground and moisture barrier. Sheathing also uses one corrugated steel tape. between inner and outer sheath to provide a mechanical protection. The sheath is ussually over printed to identity the type of cable of a particular point.
Optical Fiber Design
Each fiber is made of high purity Silica (SiO2) glass doped with Germanium (GeO2) and fused (SiO2) depressed cladding design for excellent geometrical properties for splicing and micro bending resistance. This fiber core is protected by two layers of UV - curred acrylate coating which is strong and durable enough to stand up to the challenge such as; micro bending losses, abrasion resistance, etc but remain easy to strip and splice.
Basic Cable Design
The cable core consist of stranded-six or eight thermal plastic elements with a central strength member. Elements couldbe either tubes, filler rods and or copper conductors. The coloured Polybutylene Terepthalate (PBTP) tube contains 4, 6, or 12 coloured fibers with its configurations (table 1 and 2) and water blocking compound to prevent moisture/water penetration and axial migration. Copper conductors, which stand for media of power supply for lighting, repeater, etc, are twisted in quad with cellular-solid insulation. The overall cable core is covered with flooding compound, water blocking tape and also protected by polyethylene sheathing.