輸電導線劣化原因分析

A Case Study About Deterioration of ACSR Conductor

本文探討沿海輸電導線（ACSR）長期曝露於海鹽環境中，由輸電導線外觀觀察導線外層鋁素線易斷股，內層絞線間大量腐蝕生成物沉積，鋼心線銹蝕，在更換導線時鋁素線很容易被扯斷，因此進行導線劣化因素分析。試驗方法包括腐蝕生成物分析、外觀腐蝕分析、腐蝕率及線徑損耗分析、鋁素線熱性質分析、機械強度分析、電氣特性分析、材質金相微觀分析等，綜合分析結果粉狀腐蝕生成物的化合物組成主要為Al（OH）3及AlOCl與C-O-C鍵油脂，鋁素線表層長滿白色腐蝕生成物，愈內層孔蝕愈嚴重，鋁包鋼素線表面鋁層嚴重腐蝕鋼心素線外露，海鹽氯離子是導致鋁素線加速孔蝕的主因，各層鋁素線、鋁包鋼素線、絞合鋁包鋼心鋁線破壞強度及伸長率皆低於規範值，主要受腐蝕及長期荷重影響，鋁素線的平均導電率皆約少於規範平均值3%，電阻係數則較規範值高約5%，鋁包鋼素線的電阻皆約高於規範值94.45%，檢測同批號導線發現斷股或大量腐蝕生成物時，儘速更換，避免機械強度不夠而扯斷與消耗電力成本。

ACSR was long-term exposure in the salty environment, lead the severity corrosion in aluminum wire, a great deal of corrosive accumulate inside the layer, the steel wire becomes rusty eclipse, The aluminum wire was pull to break easily after maintains, so this study was analysis deteriorate in conductor. Experimental method includes corrosive analysis, appearance analysis; radius loses corrosion rate, machine strength and metallographic analysis etc. According to analyze result the corrosive was Al(OH)3 and AlOCl and C-O-C grease, the white corrosive decorate in aluminum wire surface layer, inside layer pitting serious, The steel cladding was serious corrosion, the chlorine ion is a main cause pitting, The strength and elongation rates in each aluminum layer, steel wire and ACSR were low than specifications ,The mainly affect was corrosion and long-term loading, When examination and detection a great deal of breakdown ACSR, change as soon as possible, Avoid the machine strength not enough pulling to break and consume the electric power.