Renovation of three spillway Tainter gates


The Ribiera Dam is in the River Eume basin, north-west Galicia, in the province of La Coruña. INHISA HIDRAULICA S.A. performed comprehensive renovation of three spillway Tainter radial gates for Endesa, and replaced and modernised their drive system, which were in an advance state of deterioration and inoperability after over 50 years of use.



Work execution period: July 2016 – October 2016

The work performed involved:

  • Installation of platforms and scaffolding systems, one per span, for safe works execution.
  • Cutting and dismantling of the gate arms for extraction and renovation.
  • Extraction and removal to workshop of the gate skin plate arms using two truck cranes and a self-propelled crane.
  • Comprehensive renovation of the skin plates in the workshop, including Sa 2½ blast cleaning, renovation of the damaged structure, renovation of the parts of the skin plate in poor condition, installation of stainless steel support bands for the drive system and application of the new surface treatment.
  • Workshop renovation of the gate arms, dismantling the bushes from the shafts, design, machining and installation of a new system of maintenance-free ball joints and surface treatment.
  • Replacement of existing carbon steel fixed parts with new stainless steel fixed parts.
  • Removal of the old drive system and installation of the new support structure.
  • Mounting of the arms and skin plates of the renovated gates on site.
  • Design, fabrication and installation of the new hydraulic cylinder-driven actuation system and a novel maintenance-free naval quality chain return system.
  • Installation of a new hydraulic power unit and one new electrical command and control panel per gate, with connection and testing.