KEPCO Journal on Electric Power and Energy

Korea Electric Power Corporation (한국전력공사)
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Metallurgical Failure Analysis on a Suspension Clamp in 154kV Electric Power Transmission Tower

  • Lee, Jaehong (KEPCO Research Institute, Korea Electric Power Corporation) ;
  • Jung, Nam-gun (KEPCO Research Institute, Korea Electric Power Corporation)
  • Received : 2020.07.01
  • Accepted : 2021.09.27
  • Published : 2021.12.30
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Abstract

Failure of a suspension clamp made of hot dip galvanized cast iron in 154kV transmission tower was investigated. Metallurgical analysis of a crack of the clamp was performed using a digital microscope, an optical microscope, and a scanning electron microscope. It was revealed that the crack surface was covered by continuous zinc layer. Distinctive casting skin was found underneath both the outer surface and crack surface. The result showed that pre-existing crack had been formed in the fabrication, and liquid metal embrittlement during hot dip galvanization may assist crack propagation.

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References

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