Inspection and maintenance innovations for hydropower generation equipment

The deterioration of hydropower generation structures and equipment reduces efficiency and increases the risk of failures. Hydro-Québec has developed in situ solutions that will extend the service life of installed hydropower generation equipment such as turbines and gates and minimize service interruptions associated with inspections and refurbishment.

Assessing the actual condition of submerged structures such as concrete dams is a significant challenge, given the depth and turbidity of the water and the strength of the current.

Another major challenge is accurately measuring the flatness and profile of underwater parts to ensure the proper operation of the structure.

Our inspection and maintenance solutions were specifically designed for these conditions in order to respond to the needs of the hydropower generation environment.

Scompi – In situ repairs on turbines and other steel equipment

The Scompi system is an alternative to replacing and factory-refurbishing turbines. It is also able to perform in situ repairs of guide rails and spherical valves. Originally designed to work on complex surfaces such as Francis, Kaplan or Pelton runners, this robotic system has also proved itself in factory settings, where it can automate a number of manufacturing steps.

Rugged and compact, Scompi can be installed quickly, thus reducing intervention and repair time and increasing generating-unit availability.

Scompi benefits

  • Compact and lightweight – easy to deploy
  • Rugged and reliable – designed for hostile generating station environments
  • Accurate – refurbishments of unmatched quality
  • Efficient – suitable for in situ work

Scompi applications

  • Preventive overlay and reinforcement welding
  • Grinding and laser measurement
  • Assembly welding (turbine runners and penstocks)
  • Polishing complex surfaces (turbine runners)
  • Hammering residual stresses from welding
  • Heat treatment for repairing carbon steel and martensitic stainless steel (under development)
  • In situ work:
    • Repairing and reinforcing turbine runners
    • Refurbishing guide rails and gate edges
    • Repairing sealing surfaces of spherical valves
    • Reprofiling turbine runners
  • Manufacturing: welding, grinding and polishing of turbine runners
  • Construction: welding penstocks

Value creation

  • Savings associated with in situ work:
    • Reduced generation equipment downtime
    • Extended equipment service life
    • Improved working conditions for welders and operators
    • Deferred investments
  • Savings associated with manufacturing:
    • Enhanced productivity
    • Shorter production cycles
    • Improved weld and surface finish quality


Click to enlarge
  • Weight: 38 kg
  • Load capacity: 15 kg
  • Reach: 940 mm
  • Typical runner diameter for in situ repairs: 4 m and over
  • Processes: welding, grinding, measurement, polishing, hammering and heat treatment (under development)