Project Overview:
Anchor-Link Refurbishment on 400 kV Powerlines – Namibia
Skywolff Namibia completed a large-scale refurbishment project on three critical 400 kV powerlines in Namibia, which are integral to importing power from South Africa.
The powerlines feed a large portion of the country including a zinc mine near Rosh Pinah. The powerlines have a combined power carry capacity of 2,200 MW and span across the following routes:
- Aries SS (South Africa border) – Kokerboom SS (Keetmanshoop)
- Kokerboom SS (Keetmanshoop) – Obib SS (Rosh Pinah)
- Kokerboom SS (Keetmanshoop) – Auas SS (Windhoek)
The powerline structures are 525HS guy-rope towers, each supported by four stay wires and anchor-link foundations. After 20 years of service, these anchor links were found to be severely rusted, posing a significant risk to the powerlines’ stability and operation.
Independent consulting engineers conducted an in-dept study to understand to cause and best practical solutions to refurbish these structures. The purpose was to significantly extend the lifespan of the powerlines and to circumvent any future corrosions problems.
Therefore, each anchor-link had to be excavated and exposed up to the concrete foundations, treated and cast in concrete sleeves to 150mm above ground level.
Key Achievements of the Project:
- Refurbished 7,944 Anchor-Links: All the anchor-links were successfully exposed, treated, and casted in concrete to at least 150mm above the natural ground level (NGL). Thereby, ensuring structural integrity and eliminating future corrosion issues.
- Extended Service Life: The project ensured the continued reliability and safety of the 400 kV powerlines, securing a critical energy supply for both general power import and the dedicated feeder to the zinc mine.
- Maintained Power Flow: Despite the extensive scope of the refurbishment, careful planning and execution allowed for all works to be completed under live conditions, hence zero disruption to the power transmission.
- Future-Proofed Infrastructure: By restoring the anchor links, the project extended the life of the infrastructure and ensured its resilience for future operations.
Skywolff Namibia’s refurbishment of the anchor links on these high-capacity powerlines demonstrates its ability to manage and complete large-scale infrastructure projects with precision and efficiency.
