金屬接頭耐蝕性改善研究

Corrosion Prevention for Metal Cable Closures

鉛管為最常使用之地下電纜接頭材料。由於大多數的人孔經常充滿來自於周圍環境的地下水，若有侵蝕性物質意外流入人孔，可能導致人孔內之鉛管接頭加速腐蝕而影響其長期使用的安定性。本研究乃針對犧牲陽極的陰極保護及有機塗層等防蝕措施，在模擬加速腐蝕環境中，應用電化學交流阻抗及測試技術，評估其用於鉛管的可行性及耐蝕性改善效益。研究結果顯示，鋅犧牲陽極可陰極保護鉛管免於強酸或鉛工臘的侵蝕。以塗裝對鉛管在地下水中的保護性而言，抑銹底漆塗裝優於環氧樹脂塗裝系統。

Lead tube is usually used as the metal closure of Underground Cable. A large percentage of manholes are usually flooded, and some corrosive pollutants containing in the flooded manhole may corrode the metal cable closure and therefore cause severe problem in the telephone cable plant. In this study, the performance of organic coatings as well as the sacrificial anode for corrosion protection to lead tube are evaluated by the electrochemical impedance spectroscopy technique in an accelerated laboratory test. Zinc sacrificial anode is demonstrated to provide the lead tube an excellent corrosion protection from the strongly aggressive acid and solder flux. For the coating performance in the underground water, the rust inhibitor primer is superior to the epoxy coating.