高压输电耐张线夹的腐蚀行为及其影响因素

摘要

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.%将JY-120/20型压接管和LGJ-120/20型钢芯铝绞线压制成耐张线夹,采用电化学法以及干湿交替周浸法研究了该线夹在不同pH和温度的5%(质量分数)NaCl溶液中的腐蚀行为,测试了电阻并观察了腐蚀形貌,分析了腐蚀影响因素.结果表明:耐张线夹的电阻随腐蚀时间的延长总体呈增大趋势,但由于腐蚀过程中腐蚀产物的生成与脱落,在增大趋势中出现次级波动;腐蚀优先在压接管内部缺陷处发生,逐渐向无缺陷区域发展,并在腐蚀产物脱落的区域向深处发展;随着腐蚀溶液pH的降低或温度的升高,线夹的腐蚀速率增大.