Open AccessCorrosion Analysis of Connecting Bolt Used for Terminal Block of Isolation Switch in 220kV Substation
Author(s) -
Hao Chen,
Weili Gong,
Xueguang Qiao,
Yunfei Sun
Publication year - 2020
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1676/1/012124
Subject(s) - corrosion , lead frame , coating , materials science , terminal (telecommunication) , block (permutation group theory) , galvanic isolation , structural engineering , metallurgy , composite material , forensic engineering , engineering , electrical engineering , voltage , telecommunications , semiconductor device , geometry , mathematics , layer (electronics) , transformer
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.