1, pre-set on the cable splicing parts with steel wire heat-shrinkable sleeving;
2, remove the coating layer, with the coating pliers vertically clamped fiber, and quickly stripped 20mm - 30mm long primary coating and secondary coating layer, with alcohol-soaked cotton balls or lens paper to test the fiber, wipe the core clean to avoid cracks and scratches on the fiber surface.
3, cutting optical fiber, making the end face. In the fiber optic splicing, the most critical process, is the production of fiber end face. The perfection of the fiber end face or not determines the loss of the fiber splice. Fiber endface not only needs to end flat, showing a smooth and flat mirror area, no burrs, no defects, and axis perpendicular, but also need to keep the endface clean, to avoid dust pollution.
The end face is produced in the following three ways: Firstly, the scoring method. Using a mechanical cutting knife, a diamond knife is used to score the surface in a direction perpendicular to the optical fibre, 10mm from the coating layer, gently bouncing and touching, and the fibre is naturally broken at this score position. Second, the cutting pliers method, which is the use of a homemade handheld simple pliers for cutting operations. The third is the ultrasonic electric cutting method. These three methods as long as the apparatus is excellent, proper operation, the preparation of the end face are very good results.
4, the two optical fibres to be spliced into the fusion splicing machine, by the fusion splicing machine automatically for fusion splicing.
5, with OTDR instrumentation for splicing performance testing and evaluation, meet the splicing indicators, and then the splicing part of the reinforcement protection, that is, hot melt the heat shrinkable tube with steel wire.
6, finally, in all fiber core splicing is completed, the income of the shelter tray, OTDR instrumentation for re-testing, failed to re-housing or re-connecting, until qualified. Single-mode fiber splicing loss indicator is generally 0.08dB. in construction, according to the actual situation, but generally are not greater than 0.08dB.
Fiber optic splice loss is due to the splice point is not perfect, the impact of the splice point is not perfect factors, summarized in two categories, namely external and internal factors.
Internal factors are the imperfection of the fiber itself, can not improve the splicing process to reduce the loss, it includes core diameter mismatch, refractive index distribution mismatch, poor concentricity of the fiber, mode field diameter mismatch, so in the splicing test, the splicing loss value will appear large positive and negative phenomenon. Through multiple splicing can only make the one-way value smaller, the average value tends to zero, but the positive and negative phenomenon can not be avoided, positive and negative phenomenon on the fiber transmission loss has a certain impact. In the project, the fiber optic cable distribution plate should try to use the same batch of ex-factory fiber optic cable, A, B end as far as possible one by one correspondence, to a certain extent can reduce the splicing loss.
External factors are not the optical fiber itself is not perfect, but the splicing process caused by poor. External factors have strict requirements for splicing personnel. The core position lateral, longitudinal, fiber axial angle deviation, fiber end contamination and other phenomena, is caused by the splicing process of the fusion splicer maintenance is not timely, improper operation and other human factors.
Finally, it should also be noted that the heat shrink tube should also be clean, clean, dust-free, or hot fusion, dust damage to the splice point, causing increased loss. When collecting into the receiver tray, try to collect into large circles to avoid the increased loss caused by small circles. Fiber optic in the shelter plate to use the tape to make it fixed, can not appear on the trend of spring, to avoid future damage.
