Corrosion Behavior and Influencing Factors of Strain Clamp for High Voltage Electricity Transmission

JY-120/20 press-connect-tube and LGJ-120/20 steel-cored aluminum strand were pressed to strain clamps. The corrosion behavior of the strain clamp was investigated by the electrochemical measurement and dry-wet immersion test in a 5wt% NaCl solution with various pH values at different temperatures. The resistance was tested and the corrosion morphology was observed. The influence factors of corrosion were also analyzed. The results show that the resistance of strain clamp generally showed an increasing trend with the elongation of corrosion time. However, due to the formation and spalling of corrosion products during the corrosion process, the secondary fluctuations in the increasing trend were observed. The corrosion preferentially occurred at the inner surface defects of the press-connect-tube, and then extended to the non-defect area. At the spalling area, the corrosion developed into the inner of the tube. The corrosion rate of the strain clamp increased with the decrease of pH value and increase of temperature of the corrosion solution.