UHVDC Large Tonnage Composite Insulators are Replaced Successfully in Gansu Province

HIMALAYAL - SHANGHAI - CHINA

It is the first time that the Gansu Electric Power Maintenance Company has managed to replace ±800kV large tonnage composite insulator during the maintenance process of UHVDC Tianzhong line on October 8, filling the technology gap of the field in Gansu province.   

The 800kV UHVDC Tianzhong transmission line starts from Hami converter station, city of Hami, Xinjiang Uygur Autonomous Region of China to Dameng converter station, city of Zhengzhou, Henan province. The length of transmission line is about 1350km within Gansu province while Gansu Electric Power Maintenance Company is in charge of up to 620km line, covering three cities - Wuwei, Baiyin and Qingyang.        


Professional technicians were organized and dispatched to conduct on-the-spot investigation by the company. Technicians did detailed calculations, verified instrument stress, worked out and optimized a workable operation scheme given that the length of span of composite insulator to be replaced is long and vertical stress is great.  

The length of external packing of composite insulator is 12m or so and the total weight is up to 150kg; the tower of to-be-replaced insulator is located in the forest with a slope of 30 degree. Hence, it is very difficult to transport materials and install the insulator. The company organizes elite staff in advance and tools and instruments are carried to working site on time. In accordance with the standard process, the staff who climbs the tower coordinate with those on the ground and make it.