Project challenges
Built in 1921 and located on the French-Swiss border, the Chancy-Pougny dam generates electricity for the inhabitants of the canton of Geneva while regulating the flow of the river.
To comply with earthquake-resistant standards, the Société des forces motrices de Chancy-Pougny (SFMCP) was looking for an industrial partner capable of restoring the four gates of this hydroelectric structure, with a view to improving :
- Durability
- Performance
- Reliability and safety
- ease of maintenance
To achieve this, SFMCP surrounded itself with experts and technical assistants such as the Compagnie Nationale du Rhône (CNR) and SPRETEC, in charge of engineering and operations management (ATMOE).
L’ élément suivant est une vidéo [Video] Customer testimonial : Chancy-Pougny hydroelectric dam
Eiffage Métal's involvement in the project
In a consortium with the Swiss company MEGA SA, in charge of the anticorrosion protection of the equipment, Eiffage Métal took charge of the renovation of the structures and motorization of the four gates:
- Design of the mechanics and winder work
- Establishment of complete and detailed intervention methodologies by phase
- Procurement, monitoring and quality control of replaced mechanical parts
- Structural reinforcement of valves with associated NDT
- Corrosion protection work, scaffolding and heat-shrink containment (co-contractor)
- Assembly of valve mechanical parts (rollers, blocks, pinions, seals, STONEY carriages, etc.)
- Dismantling and replacement of operating elements, including all associated sensors and instrumentation (dynamo axes, winders, encoders, overspeed).
Key figures for the dam
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+100years of existence
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50 MWof power
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240 GWhannual electricity production
Eiffage Métal's expertise in the project
The major challenge of this renovation was to work on historic infrastructures dating back over 100 years.
To ensure that the techniques and processes envisaged would be compatible with the existing equipment materials, Eiffage Métal's teams carried out a series of preliminary assessments:
- Material sampling with laboratory chemical analysis
- Determination of equivalent carbon content (verification of weldability)
- Methylene blue imprints were taken on the teeth to reconstitute the pinion profiles with a view to replacing certain gears.
- Hardness measurements on wheels (material definition)
- 100% penetrant testing on gear teeth (wear analysis and prevention of alarm signals)
- Drafting of a fatigue study to establish a short- and medium-term action plan (repair or replacement).
Key figures for valves
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4valves
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12meters wide
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80tons
Why Eiffage Métal?
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Recognized expertise
in the industrial and hydraulic sector
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Turnkey solutions
Control of all phases, from design to installation
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Mastering technical constraints
adaptation to the specific characteristics of the site and existing infrastructure
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Anticipating requirements
social, fiscal, environmental, safety, to work in Switzerland
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Customized technical proposals
flexibility to adapt to project changes
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Partnership with a Swiss co-contractor
knowledge of country-specific regulations
