Fiber splicing is mainly divided into four steps: stripping, cutting, melting, and protecting.
The so-called stripping: refers to stripping out the optical fiber core in the optical cable, which includes the outermost plastic layer, the steel wire in the middle, the plastic layer in the inner layer and the color paint layer on the surface of the optical fiber. .
The so-called cutting refers to using a "cutting machine" to cut the end faces of the optical fibers that have been stripped and prepared for splicing.
The so-called fusion: refers to the splicing of two optical fibers together in a "fusion splicer".
The so-called protection: refers to protecting the fused optical fiber connector with a "heat shrink tube".
The operation of each step will be introduced in detail below. The first is the preparation of the end face. The preparation of the optical fiber end face includes stripping, cleaning and cutting.
Qualified optical fiber end face is a necessary condition for welding, and the quality of the end face directly affects the quality of welding.
(1) To remove the optical fiber coating, master the three-character stripping method of smooth, steady and fast.
"Flat" means that the fibers should be held flat.
Pinch the optical fiber with the thumb and index finger of your left hand to make it horizontal. The exposed length is 5cm. The remaining fiber is naturally bent between the ring finger and little finger to increase the strength and prevent slipping.
"Stable" means that the fiber stripping pliers should be held firmly.
"Quick" means stripping the fiber quickly. The fiber stripping pliers should be perpendicular to the fiber and tilted upward at a certain angle. Then use the jaws to gently clamp the fiber, and then use your right hand to apply force along the fiber axis. When pushing it out to the flat surface, the whole process should be natural and smooth, and done in one go.
(2) Cleaning of bare fiber: Observe whether the coating layer of the stripped part of the optical fiber has been completely stripped off. If there is any residue, it should be stripped off again.
If there is a very small amount of coating layer that is difficult to peel off, you can use a cotton ball dipped in an appropriate amount of alcohol and gradually wipe it off while dipping it.
A piece of cotton should be replaced in time after being used 2 to 3 times. Different parts and layers of cotton should be used each time. This can not only improve the cotton utilization rate, but also prevent double contamination of the fiber probe.
(3) Cutting of bare fiber: Cutting is the most critical part in fiber end-face preparation. Precision and excellent cutters are the foundation, and strict and scientific operating specifications are the guarantee.
Cutter selection There are two types of cutters: manual and electric.
The former is simple to operate and has reliable performance. With the improvement of the operator's level, the cutting efficiency and quality can be greatly improved, and the bare fiber is required to be shorter, but the cutter is sensitive to the environmental temperature difference.The requirements are higher.
The latter has higher cutting quality and is suitable for working in cold conditions in the wild, but the operation is more complicated, the working speed is constant, and the bare fiber is required to be longer.
Skilled operators are better off using manual cutters when performing fast fiber optic cable splicing or emergency operations at room temperature; conversely, beginners should use electric cutters when working in colder conditions in the field.
Operating specifications Operators should undergo special training to master the essentials of movements and operating specifications.
First of all, clean the cutter and adjust the position of the cutter. The cutter should be placed stably. When cutting, the movement should be natural and smooth, not heavy or urgent, and avoid fiber breakage, bevel, burr, etc. The occurrence of cracks and other bad end surfaces.
In addition, learn to "play the piano" and properly allocate and use the fingers of your right hand to correspond and coordinate with the specific parts of the cutter to improve cutting speed and quality.
Beware of end face contamination. The heat shrink sleeve should be inserted before stripping. It is strictly prohibited to insert the heat shrink sleeve after the end face is prepared.
The cleaning, cutting and welding time of bare fiber should be closely connected, and the interval should not be too long. In particular, the prepared end face should not be left in the air.
When moving, handle it with care to avoid collision with other objects.
During the connection, the "V"-shaped groove, pressure plate, and blade of the cutter should be cleaned according to the environment to prevent end surface contamination.
Optical fiber splicing is the central link in splicing work, so high-performance splicing machines and scientific operation during the splicing process are very necessary.
(1) Selection of fusion splicer The selection of fusion splicer should be equipped with welding equipment with appropriate battery capacity and precision according to the requirements of the optical cable project.
(2) Parameter setting of fusion splicer: Before splicing, according to the material and type of optical fiber, key parameters such as optimal pre-melting main fusion current and time and optical fiber feeding amount should be set.
During the welding process, the "V"-shaped groove, electrodes, objective lens, welding chamber, etc. of the welding machine should also be cleaned promptly, and any undesirable phenomena such as bubbles, excessive fineness, excessive thickness, virtual melting, and separation should be observed at any time during the welding. , pay attention to the OTDR tracking and monitoring results, promptly analyze the causes of the above adverse phenomena, and take corresponding improvement measures.
If virtual fusion occurs multiple times, check whether the materials and models of the two spliced optical fibers match, whether the cutter and fusion splicer are contaminated by dust, and check the oxidation status of the electrodes. If there are no problems, The welding current should be appropriately increased.
Fiber coiling: Fiber coiling is a technology and an art.
The scientific fiber coiling method can make the optical fiber layout reasonable, with low additional loss, withstand the test of time and harsh environments, and avoid fiber breakage caused by extrusion.
Conclusion: Optical cable continuity is a meticulous work, especially in end face preparation, welding, fiber coiling and other links, which requires the operator to observe carefully, consider carefully and operate in a standardized manner.
In short, at work, we must cultivate a rigorous and meticulous work style.Only by being diligent in summarizing and thinking can we improve practical operation skills, reduce splicing losses, and comprehensively improve the quality of optical cable splicing.
