AUD $8 million
Commissioned in 1965, the Poatina Penstock carries water to the Poatina Powerstation, which is Hydro Tasmania’s second biggest powerstation.
The condition of the original anti-corrosion paintwork on the penstock interior was beginning to deteriorate, which posed a risk to power and water supply and could mean costly premature replacement of the pipeline.
The project involved the removal of the internal coating of the penstock and the application of a new coating. The works were completed over the length of the above ground penstock, 150m below ground vertical shaft, below ground distributor and short sections of the tunnel leading directly from the lake.
The penstock was typically 2.5 – 3.0m in diameter and 1,800m long with a surface area of approximately 16,000m2.Specifically this project involved:
- The removal of the existing coal tar enamel coating using an ultrahigh pressure water blasting robot.
- Preparation of the steel surface using a combination of grit blasting by hand and via robot.
- Capture of the waste from the cleaning and preparation phases and disposal of it in an environmentally sound manner.
- Application of the primer by hand and the build coat via a paint robot.
This complex and challenging project was successfully executed over Tasmania’s harsh winter months, with minimal disruption of water services to end users and with a pleasing result in quality and health and safety. This was largely due to TBS’ innovative approach and commitment to developing engineering solutions to the many access, health and safety and environmental challenges of the job.