Method Of Repairing Opgw Broken Strands With Pre-twisted Wire

Abstract: Due to various reasons, the outer single wire of OPGW may break or become loose during use. The method of replacing the tension section is often used for repair, but sometimes it is limited by time and economy. This paper discusses the conditions under which OPGW can be repaired by repair strips without replacing the optical cable. The mechanical and electrical properties of the repaired wires are close to the initial technical requirements of OPGW and meet the design requirements for normal operation of the line.
Keywords: OPGW; armour rod in transmission line repair strips; tensile test
I. Analysis of the causes of OPGW breakage
In recent years, OPGW has been widely used in domestic power systems, which has brought huge benefits to the efficient and safe operation of my country's power system and provided the best transmission medium for the rapid establishment of high-speed and large-capacity power optical fiber communication networks.
OPGW first exists as an overhead transmission ground wire, which must work under relatively harsh line conditions and meteorological conditions.
The most common defects and faults in operation are the breakage or loosening of the outer single wire.
According to statistics and analysis, there are many reasons for the breakage of the outer single wire of OPGW:
(1) Reasons related to raw materials or manufacturing quality. Such as impurities in raw materials, poor tensile properties of raw materials, joints in the outer monofilament during manufacturing, uneven monofilament tension at armor rods conductor, etc.
(2) OPGW in high thunderstorm areas, broken strands due to lightning strikes.
(3) Uneven ice coverage in heavily iced areas causes overload, or ice shedding at different times causes jumping or dancing, which produces large impact force and unbalanced tension, resulting in broken strands of the outer monofilament.
(4) Some unpredictable external forces. Such as blasting in quarries, hunters shooting, strong typhoons and other external factors.
After the OPGW strands are broken, sometimes even though its communication performance is not affected, the mechanical strength of the OPGW is reduced. Long-term operation may not only affect the safe operation of the transmission line, but also threaten the reliability of power system communication and protection.