What to do when the optical cable is spliced
A. Pay attention to the cutting depth when the optical cable is stripped. The key to stripping the outer sheath of the optical cable is to master the cutting depth of the sheath cutting knife, otherwise, it is easy to break the fiber. In actual operation, the sheath cutter should be rotated while watching the incision. If you can see the white polyester tape, you should stop the knife and remove the cutter. This step is a proficient process and requires many exercises to master the depth of penetration.
B. Fixing of optical cable and stripping of fiber bundle tube. After the optical cable is stripped, fix the optical cable in the optical cable joint box, strip the core bundle tube, and do all preparations before splicing the optical fiber.
Attention should be paid at this time
1.) The core bundle tube cannot be twisted. Before fixing the optical cable, you must pay attention to the location of the core bundle tube. When the reinforcing member passes through the fixing screw, the filler tube must be filled under the reinforcement member, not the core bundle tube. The core bundle tube must be in the reinforcement member to enter the fiber On the same side of the containment tray, it cannot be twisted on the reinforcement. If the reinforcement is pressed against the core bundle tube, the core bundle tube will be deformed due to the force and the loss will be too large, and the optical fiber in the core bundle tube will also be broken due to long-term stress, leaving hidden dangers to the project.
2.) The length of the reinforcement must be appropriate. After the position of the fiber bundle tube is determined, the optical cable can be fixed. The fixing of the optical cable must ensure that the position of the optical fiber in the splice box will not be loosened to avoid the increase of optical fiber loss or fiber breakage due to the movement of the optical cable position. The fixing of the optical cable is divided into the fixing of the reinforcement and the fixing of the rest of the optical cable. Pay attention to the length of the reinforcement. It is too long to fit in the connector box. Too short is not enough to fix the optical cable. Generally, when cutting the reinforcement, the distance between the splint for fixing the optical cable and the screw for fixing the reinforcement should be equal to the length left. The rest of the optical cable is fixed after the reinforcement is fixed, and the clamping plate is tightened with screws to tightly fix it at the entrance of the optical cable of the joint box.
3.) The stripping length of the core bundle tube should be appropriate. After the optical cable is fixed, the core bundle tube can be stripped. If the stripping length is too long, it will reach the groove of the fiber heat shrink tube, and the residual fiber will be damaged when the fiber is coiled. Therefore, it is generally appropriate to peel it into two fixed bayonets. At this length, the core bundle tube will not cause damage to the optical fiber and can be fixed well. However, the clips cannot be over-tightened when they are fixed, otherwise, the optical fiber of the core bundle tube will increase the loss due to the force, and the optical fiber will break after a long time, leaving hidden dangers to the project.
C. The fusion of optical fiber. Fiber connection is directly related to the quality and life of the project, and the key lies in the preparation of the fiber end face. The fiber end face is smooth, without burrs or defects, and the fusion splicer can be well confirmed and can make a joint that meets the engineering requirements. If the fiber end face is unqualified, the fusion splicer refuses to work, or the spliced connector is very lossy, not Meet the engineering requirements. In the process of making the fiber end face, firstly when stripping the coating layer of the optical fiber, the stripping pliers should be perpendicular to the fiber axis to ensure that the stripping pliers do not scratch the optical fiber; when cutting the fiber, it is necessary to strictly follow the regulations and use end face cutting The knife should be accurate in cutting length, fast in movement, and hard in force, to ensure that the optical fiber is broken, not crushed; when taking the optical fiber, make sure that the optical fiber does not touch any objects, to avoid scratching the end face, so do The end face that comes out is smooth and qualified. The fusion splicer is key equipment for optical fiber fusion splicing, and it is also a highly precise and expensive device. In the process of use, it must be operated strictly in accordance with the regulations, otherwise, it may cause significant losses. Special attention should be paid to the operation procedure of the fusion splicer. The length setting of the heat-shrinkable tube should conform to the requirements.
D. Protection of residual fiber After the optical fiber is spliced, the fiber must be protected by a heat-shrinkable tube, and the residual fiber must be retained.
Pada masa ini, attention should be paid to 1.) In the process of fiber coiling, the bending radius of the coiled fiber should not be too small, generally not less than 4mm. If the bending radius is too small, it is easy to cause excessive refractive loss and increased dispersion. Over time, fiber breakage may also occur.
2.) When reeling the fiber, pay attention to the twisting direction of the fiber. Generally, it is an inverted “8” shape. Be careful not to twist the fiber. After the reel, put the fiber into the baffle of the receiving tray to avoid damage to the fiber during packaging.
E. Sealing of the connector box The sealing of the optical cable connector box is very important in practical projects. Because the surface of the optical fiber is easy to produce micro-cracks after the water enters the connector box, the optical fiber will break after a long time, and the connector box is mostly buried directly in the ground, so the connector box must be sealed. The sealing of the joint box is mainly the sealing of the two parts between the optical cable and the joint box, and the upper and lower covers of the joint box. When sealing the optical cable and the connector box, you must first polish the cable jacket at the seal. and use gauze to polish the outer cable perpendicular to the axial direction of the cable to make the cable and sealing tape tighter and better seal . The seal between the upper and lower cover plates of the joint box is mainly to pay attention that the sealing tape should be evenly prevented in the sealing groove of the joint box. Tighten the screws without leaving any gaps.
Masa pos: 2020-04-25