OPGW耐张线夹/ Dead-end for OPGW
U型挂环/Shackle, PD挂板/ Clevis Hinge (Type PD), 心型环/Thimble Clevis, 耐张线夹/ Dead-end Component, 内层护线条/ Structural Reinforcing Rod Component, OPGW, 接地线/ Grounding Wire, 色标/ Color Code And Crossover Marks
功能用途/ Function and Purpose
The clamp bears the tensile force. OPGW is connected to strain pole or tower with the clamp.
产品特点/ Product characteristic
² The clamp connects with the pole or tower and bears the line load
² Cables are finely protected because stress is equally distributed without intensive stress pivot.
² The clamp provides great gripping power in the premise no more than the edgewise compressive strength of cable.
² The grip is more than 95%RTS of OPGW and protect cable not be damaged.
² The materials of rod selected good quality aluminum covered steel wire are against corrosion and improve the mechanical properties.
技术要求 / Technical Requirements
Compliant with DL/T 766-2003: Technical requirements and testing method of helical fittings for OPGW.
选型方法/ Lectotype Method
² According to the diameter and strength of OPGW.
² Number of configuration: 2 sets / Strain pole or tower
2 sets / Connecting pole or tower
1 set / Terminal pole or tower
² Provides the connection type of the first fitting when connection with the pole or tower.
² Strength class: 60kN, 80kN, 100kN, 120kN.
Generally, the requirements for OPGW cable hardware connector box are as follows:
① It has good expansibility of optical cable channel, that is, the smaller the attenuation of cable connection introduced by OPGW cable connector box, the better. Connection attenuation is not only related to the structure of junction box, but also related to the technical level of construction and installation personnel;
② The junction box of optical cable has good sealing effect and protects the optical fiber core in the box from the influence of external environment. Because the OPGW optical cable joint box is installed on the power tower, mostly in the field, river, mountain and other harsh environment, it is required to have the functions of moisture-proof, waterproof, external force, temperature resistance, etc., and the sealing requirements are high. The splice box shall consist of the enclosure, internals, sealing elements and fiber splice protectors. The shell shall be made of high-strength materials such as stainless steel or aluminum alloy; the sealing elements are used to seal the junction box itself and the sealing between the junction box and OPGW.
The sealing method can be divided into mechanical seal and heat shrinkable seal. Mechanical seal is made of adhesive, vulcanized rubber, non vulcanized self-adhesive rubber, paste seal mixture and other mechanical seal methods. The heat shrinkable seal is made of polyolefin heat shrinkable pipe or sheet coated with hot melt adhesive on the inner wall after heating; the optical fiber joint protection can be of heat shrinkable type or non heat shrinkable type. The installation and construction technology of OPGW cable joint box has an important impact on the quality of the joint box. If the construction is not standardized and the technology is not in place, the sealing effect of the junction box is not ideal, and some will directly damage the optical cable.
At present, in most cases, in order to meet the leakproof requirements, after the construction and installation of OPGW optical cable junction box, unless the junction box is damaged or the attenuation of optical fiber core in the box is too large, resulting in channel interruption, it will not be opened again. In case of failure, the maintenance personnel usually directly replace the junction box. For the junction box with serious water immersion, cut off the connected optical cable by 1-2m, and shorten the length of the remaining optical cable. If the length of the remaining cable is not enough, the platform location of the junction box should be increased to make it closer to the high-voltage power line, but it increases the difficulty of maintenance construction, increases the safety risk of maintenance personnel, increases the electromagnetic field strength of the junction box, and worsens the environment. Therefore, the maintenance after the failure is not an ideal way of operation and maintenance. The operation and maintenance inspection method of joint box technology is proposed, which is used for tracking inspection of joint box and assisting regular open box inspection. According to the requirements of condition based maintenance of power communication optical cable, routine core detection shall be carried out at the initial stage of operation (1-2 years after operation of OPGW optical cable), various status quantities shall be collected and status assessment shall be carried out. During the installation and construction of the line project, the desiccant shall be placed in the junction box. After the completion of construction, the distance information and attenuation data of the line junction box are collected as the initial state information of tracking detection.
In the secondary state maintenance evaluation of OPGW cable fittings after operation, OTDR is used to test the attenuation of OPGW cable joint box, record and compare with the initial state information, select the joint box with large attenuation value change, open the box for inspection, and replace the desiccant. As the core of the optical cable is damped or soaked, it cannot be immediately reflected in the optical power loss, and the comparison of the test loss before and after can not be used as the judgment basis for the open package inspection. Once the loss value increases significantly, it means that the cable has been unable to recover the damage, only the damaged cable can be cut off, or even the entire cable can be replaced.