Open AccessFailure analysis of phase B pull rod of HGIS circuit breaker operating mechanism in 220 kV Substation
Author(s) -
Lei Lyu,
Hao Chen,
Yanfei Zhang,
Haolun Bai
Publication year - 2021
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 - 10.1088/1742-6596/1885/4/042026
Subject(s) - materials science , brittleness , composite material , fracture toughness , toughness , metallurgy , connecting rod , circuit breaker , ferrite (magnet) , alloy , electrical engineering , mechanical engineering , engineering
The B-phase pull rod of HGIS circuit breaker operating mechanism in a 220kV substation was broken at the root. The broken pull rod was analyzed by macro examination, metallographic examination, chemical composition analysis, fracture morphology analysis and impact test to find out the reason for the fracture. The results showed that: 1. Due to the improper heat treatment in the manufacturing process, the metallographic structure of B-phase pull rod appeared network ferrite and widmanstatten structure, which made the material brittle and impact toughness lower than the standard requirements; 2. The content of alloy elements Cr, Ni and Ni were significantly higher than the standard requirements, which reduced the plasticity and toughness of the material; 3. The low temperature of substation environment led to the decrease of material toughness and the viscosity of the lubricant decreased, causing the transmission parts to jam. The joint action of three factors led to cleavage fracture of B-phase pull rod in the stress concentration area.