Corrosion Analysis of Connecting Bolt Used for Terminal Block of Isolation Switch in 220kV Substation. (November 2020)

• Record Type: Journal Article
• Authors: Chen, Hao; Gong, Weiwei; Qiao, Xin; Sun, Yunfei
• Is Part Of: Journal of physics. Volume 1676(2020)
• Publication Date: 2020-11
• Subjects: Physics -- Congresses; 530.5
• DOI: 10.1088/1742-6596/1676/1/012124
• Languages: English
• ISSNs: 1742-6588

Abstract

Abstract: Isolation switch is mainly composed of insulation part, conductive part, supporting frame, transmission mechanism and operating mechanism, which is of great importance for the safety and stability of power grids. In this paper, the seriously corroded connecting bolts used for terminal block of isolation switch in 220kV substation was investigated by means of macro-morphology inspection, hardness testing, zinc coating thickness measurement, scanning electron microscope, microstructure analysis and energy spectrum analysis. The result showed that the poor quality of the zinc coating was the main cause of the corrosion failure of the bolting and the gap between the bolt and the aluminium terminal block provided electrolyte environment for galvanic corrosion. In addition, targeted suggestions were put forward in order to improve the corrosion resistance of the connecting bolts and avoid the similar corrosion failure.