Processing of OPGW cable fittings


常规产品/ General product

金属接续盒/ Metal splice closure

 

穿纤管夹/ Clamp for fiber tube, 光纤穿纤管/ Fiber tube, 光纤缠绕器/ Fiber winding device, 存纤盒/ Fiber storage box, 外壳/ Outer shell, 密封圈/ Gasket (Type O), 底座/ Bed frame, 紧固钢带/ Stainless steel tape, 安装连接器/ Link fitting for install, S型铁塔安装架/ Mount for tower (Type S), 中心螺栓/ Center bolt, 铝螺母/ Aluminum nut, 不锈钢螺母/ Stainless steel nut, 止转螺母/ Anti-rotation nut

 

功能用途/ Function and Purpose

The main function of the splice closure is fusion, protects and preformed of fiber.

产品特点/ Product characteristic

²  Prompt, easy and convenient installation.

²  Good sealing performance: 100Kpa / Constant pressure for 72 hours.

²  Scope of application: Φ24mm / 96 core of cable.

²  Whole body of the splice closure is made of high strength AL-alloy.

²  High mechanical strength.

²  Can be reused, easy to rejiont and expand capacity.

选型方法/  Lectotype Method

²  Supply the diameter and core of the cable.

²  A-O / O-O.

²  Supply the diameter of the Installation point of the pole.

²  1 set / Connecting or Terminal pole or tower


OPGW optical fiber composite overhead ground wire is mainly composed of optical fiber core unit and metal strand containing optical fiber, generally aluminum clad steel wire and aluminum alloy wire. Optical fiber provides optical signal transmission channel, steel parts mainly bear mechanical load, aluminum parts mainly bear short-circuit current. According to the different protection tube of optical fiber unit, OPGW optical cable can be divided into aluminum tube structure and stainless steel tube structure. There are two types of OPGW cable with aluminum tube structure: stranded type and aluminum skeleton type. OPGW cable fittings with stainless steel pipe structure are divided into single-layer stainless steel pipe and lined composite stainless steel pipe.


It is mainly composed of stainless steel tube optical unit, aluminum alloy wire and aluminum clad steel wire. For the optical unit of optical cable, the stranded stainless steel tube optical cable needs to meet the requirements of optical fiber stress, optical fiber heating, optical fiber moisture and other aspects to ensure the long-term and reliable survival of optical fiber in the actual application conditions.


In order to ensure that the OPGW cable will not have obvious strain and degradation of optical performance under various stress conditions, the key is to maintain the appropriate fiber surplus in the cable. For the aluminum frame fiber optic cable, because of the tight sleeve structure, there is no plastic sleeve surplus, only the stranded surplus, so the total remaining length of the fiber is small, and the stress has a greater impact on the fiber. However, it has good lateral pressure resistance and unique technical advantages under special application conditions. Whether it is aluminum tube structure or stainless steel tube structure, OPGW stranded optical cable can obtain enough remaining length by adjusting the stranded pitch. The mechanism of remaining length of optical fiber is exactly the same as that of stranded optical fiber. Especially for the fiber optic cable with composite stainless steel tube structure, due to the existence of inner lining, the maximum allowable temperature is closely related to the consumption of stainless steel tube in the process of cold drawing. In order to ensure that the instantaneous high temperature of the stainless steel optical element does not exceed the maximum allowable temperature, the short-circuit current capacity of the optical cable itself must be greater than the actual short-circuit current capacity, that is, the product of the square of the short-circuit current and the duration of the short-circuit current. Therefore, in order to improve the heat resistance of OPGW cable fittings, the short-circuit current capacity of the cable can be increased, or the actual short-circuit current size and duration can be limited. In addition to short-circuit fault, lightning is another factor that causes instantaneous high temperature of optical cable. Compared with short-circuit fault, the instantaneous current intensity of lightning stroke is larger, but the duration is generally microseconds, so the thermal capacity of temperature rise caused by lightning stroke is smaller than the thermal capacity of short-circuit fault. However, the short-circuit current acts on the whole metal section of the optical cable, while the lightning current is limited to a small section of one or several metal wires. The concentration of energy makes the high temperature on this small piece of wire enough to melt it partially or completely. This is the main reason of broken strand of optical cable caused by lightning. It can be said that lightning test refers to the instantaneous high heat capacity of each metal strand in the outer layer of optical cable. It is an effective way to improve the cross-sectional area of the outer single line to avoid lightning damage. If possible, the diameter of outer metal wire of OPGW optical cable shall be as large as possible.