Background

A 220kV transmission line in a mountainous area suffered from acid rain erosion and alternating dry-wet climate for a long time. The acid components in the rainwater accelerated the corrosion of the conductor steel core and the oxidation of the aluminum strand. The complex terrain made maintenance difficult, and the conductor corrosion developed rapidly, with hidden dangers of strand breakage.

Solution

Acid rain resistant anti-corrosion grease with good chemical stability and strong adhesion was used. The construction adopted full-length coating and key reinforcement at tower hanging points. The grease resisted acid rain corrosion, isolated alternating dry-wet erosion, and prevented the penetration of corrosive ions.

Effects

After 5 years of inspection, the conductor corrosion rate was reduced by more than 90%, the aluminum strand oxidation and steel core rust were effectively controlled, no strand breakage or strength attenuation occurred, and the line maintenance workload was reduced by 70%. It provided reliable long-term protection for overhead conductors in mountainous acid rain areas.