What is optical fiber fusion?

Absrtact: Do you know what optical cable welding is? Optical cable welding is a meticulous work, especially in the aspects of end face preparation, welding and optical fiber winding, which requires careful observation, careful consideration and standardized operation by operators. What are the operation skills of optical fiber welding? Let's briefly introduce the video network. Optical fiber welding What is optical fiber welding? Optical fiber fusion method and operation skill.

Optical cable welding is a meticulous work, especially in the aspects of end face preparation, welding and optical fiber winding, which requires careful observation, careful consideration and standardized operation by operators. This article introduces the steps and practical skills for you.

First, optical fiber welding.

Optical fiber welding is the central link of continuous work, so it is very necessary to have a high-performance welding machine and scientific operation in the welding process.

2. 1 Selection of welding machine

According to the requirements of optical cable engineering, an ultrasonic welding machine with appropriate battery capacity and accuracy is equipped. According to experience, FSM—30S arc welding machine in Japan has excellent performance, stable operation and high welding quality. It is equipped with dust-proof and wind-proof cover and large-capacity battery, which is suitable for all kinds of large and medium-sized optical cable projects. Siemens X-76 welding machine is small in size, simple to operate, equipped with simple cutter, battery and main machine integrated into one, convenient to carry, slightly worse in accuracy than the former, and small in battery capacity, which is suitable for small and medium-sized optical cable projects.

2.2 welding procedure

According to the material and type of optical fiber, key parameters such as the best pre-melting current and time and the feed rate of optical fiber are set before welding. During the welding process, the V-groove, electrode, objective lens and welding chamber of the welding machine should also be cleaned in time. Observe whether there are bubbles, too thin, too thick, virtual melting, separation and other undesirable phenomena during welding at any time, pay attention to the tracking and monitoring results of OTDR testing instruments, analyze the causes of the above undesirable phenomena in time, and take corresponding improvement measures. If virtual melting occurs for many times, check whether the materials and models of the two optical fibers match, whether the cutter and welding machine are polluted by dust, and check the oxidation state of the electrode. If there is no problem, it is necessary to increase the welding current appropriately.

Two. Principles and steps

There are three methods of optical fiber fusion: fusion, movable connection and mechanical connection. Welding method is basically used in practical engineering, because welding method has small node loss, large reflection loss and high reliability.

1, the principle to be followed when welding optical cables, when the number of cores is the same, it should be the same as the optical fibers with corresponding colors in the bundle tube; When the number of cores is different, weld more cores first, and then weld fewer cores. Common optical cables are stranded, skeleton and central tube bundle, and the core colors are divided into blue, orange, green, brown, gray, white, red, black, yellow, purple, pink and cyan. Multi-core optical cables put optical fibers of different colors in the same tube bundle to form a group, so there may be several tube bundles in one optical cable. Facing the cross section of optical cable, the red bundle tube is regarded as the first bundle of optical cable, and the clockwise direction is green, white 1, white 2 and white 3.

2, optical cable welding process

Step 1: Peel off the optical cable and fix it in the junction box. When fixing multi-bundle tube-layer optical cables, the tubes should be placed to avoid entanglement. Thread the optical cable into the junction box. When fixing the steel wire, it must be pressed tightly and must not be loose. Otherwise, the core may roll. Be careful not to damage the tube bundle. Take the stripping length of about 1 m and wipe the ointment with toilet paper.

Step 2, pass the optical fiber through the heat shrinkable tube. Separate different bundles and colors of optical fibers and pass them through the heat-shrinkable sleeve. Coated optical cables are very fragile. The optical fiber connector can be protected by using heat shrinkable sleeve.

Step 3, turn on the power supply of the welding machine and select the appropriate welding method. There are two kinds of welding machine power sources, DC and AC, which should be switched reasonably according to the current type of power source. Before each use of the welder, the welder should be left in the welding environment for at least 15 minutes. According to the type of optical fiber, welding parameters, pre-discharge time, time, main discharge time and main discharge time are set. If there are no special circumstances, automatic welding procedures are generally selected. Dust and fiber fragments in the welding machine should be removed in time during and after use.

Fourthly, the fiber end face is made. The quality of optical fiber end face will directly affect the connection quality, so qualified end face must be made before welding.

Step 5: Clean the bare optical fiber, tear the cotton into small pieces with flat surface, stick a little alcohol, clamp the stripped optical fiber, and wipe it with moderate force along the axial direction of the optical fiber, using different parts and layers of cotton every time to improve the utilization rate of cotton. Step 6: Cut off the bare optical fiber. First, clean the cutter and adjust the position of the cutter. The cutter should be placed smoothly. When cutting, the movements should be natural and smooth, neither heavy nor light. Avoid bad end faces such as broken wires, oblique angles, burrs and cracks. Step 7: Put the optical fiber into the V-shaped groove of the welding machine, carefully press the optical fiber pressure plate and the optical fiber clamp, set the position of the optical fiber in the pressure plate according to the cutting length of the optical fiber, close the windshield, and press the welding key to automatically complete the welding, and the estimated loss value will be displayed on the display screen of the welding machine. Step 8, take out the optical fiber and heat it with the heating furnace of the welding machine. Even after welding is completed, the optical cable line can be tested for failure if necessary.

Third, ensure quality.

Strengthening the monitoring of OTDR tester is of great significance to ensure the welding quality of optical fiber and reduce the extra loss caused by coil optical fiber and the possible damage caused by sealing. In the whole connection work, four monitoring procedures of OTDR tester must be strictly implemented:

1) Track and monitor each core fiber in real time during welding, and check the quality of each welding point;

2) After each winding, check the wound optical fiber to determine the extra loss caused by winding;

3) Before sealing the box, uniformly measure all optical fibers to see whether there is any missing measurement and whether the reserved space of optical fibers squeezes the optical fibers and connectors;

4) After sealing, conduct final monitoring on all optical fibers to check whether sealing is harmful to optical fibers.