A conductor holder was cut off on intermediate tower N167 of transmission line Kavkasioni (500kV) in 2016 (Russian territory). It was caused with the damage of a shakle insulator as it was broken in socket. After the inspection of the insulator it turned out that the shakle was rusty and there was also found an overlap of electric arc on cover. The process of examination also revealed the analogous defects in garlands of other intermediate towers of transmission line Kavkasioni.
Considering the above mentioned the employees of the operating-repair districts of JSC Sakrusenergo were instructed to examine all the power lines owned by the company in order to find out any possible defects on insulators. Besides the Transmission Line Kavkasioni (500kV), similar insulator defects were also found in the supporting garlands of 169 intermediate towers of transmission line “Imereti”. Correspondent act was drawn up and the number of insulators to be replaced was determined. The company considered appropriate to replace the corrosive insulators on towers, in all garlands with defects. Besides, there were also found number of dirty and broken insulators in the garlands and they will be also changed, approximately 10 insulators in each garland.
The performance of the above mentioned work is especially relevant for the prevention of emergency shut-off of transmission line Imereti. It should be noted that the transmission line Imereti is so far the only 500 kV transmission line and it has no alternative that provides the electricity transmission generated and accumulated in Engurhesi to Eastern Georgia.
Under the timetable agreed with the National Dispatch Center of Georgia, transmission line Imereti (500kV) will be under repair from March 23 to April 5, 2018.
Due to the great volume of work, restricted period of time and climate conditions the insulators on 100 intermediate towers will be replaced by the employees of the JSC Sakrusenergo in cooperation with the contractor company. The repair operation will be performed by the maintenance crew and the employees of transport office of Tsalenjikha, Zestaponi, Khashuri and Tbilisi districts of the company Sakrusenergo. The maintenance crew will also replace the damaged crossbars, renovate the bights and conduct the process of ascending inspection. About 80 employees of the company will take part into the repair activities and 25 special equipment, tools and devices will be applied for it. The management will conduct the process of coordination of the repair operations, monitor and supervise the security measures.
The repair operation will be performed on the territory of Gali, Tsalenjikha, Chkhorotsku, Martvili, Khoni, Tskaltubo, Tkibuli and Terjola municipalities, on 130km section of transmission line. In addition to repairing process on the Imereti transmission line (500kV), 5 500 isolators will be replaced in total that will significantly increase the reliability and safety of the transmission line in the forthcoming flood season.