Hydro-Disc Valve type « HDC »



  • Turbine Main Inlet Valve
  • Pump Main Inlet Valve
  • Penstock head Valve
  • Overspeed Valve

Key Features

The HYDRO-DISC valve type “HDC” is a high performance double offset butterfly valve insuring tightness under maximum service conditions.

  • Design pressure: PN2,5 to PN50
  • Diameter: DN300 to DN4000
  • The Self Energised Seal (S.E.SS) type makes the valve naturally fully tight, including large sizes
  • Solid stainless steel seat
  • Hydraulic actuator with counterweight (for closing)
  • Design dedicated to hydropower installations
  • Results of several experienced technologies in hydro environment

Design adapted to customer service conditions

  • Complete range of pressure capacity: from PN2,5 up to PN50
  • One piece body as a standard and two parts body over PN20
  • Flat-disc as a standard and lattice-disc over DN1500/PN10
  • Construction: cast carbon steel or iron body and disc, fabricated carbon steel
  • Single actuator with counterweight as a standard and double ones over DN2000/PN10
  • Other actuator type available: Electric, manual gear …

Design benefits

  • Continuous 360° sealing for a 100% full peripheral tightness
  • 100% tight closing either direction of flow
  • Reliable and long-lasting surface resisting to time and aggressive conditions
  • Low head losses
  • Low operation torque: opening/closing torques are reduced thanks the low friction seal
  • Extended longevity of the rubber S.E.S. seal since the pressure applied on the seat is only dependant from the working differential pressure

Easy and Safe Maintenance

Renewable, easily replaceable seal without dismantling the disc and without adjustment

  • The seal does not require adjustment even at the highest pressures
  • The S.E.S. seal is fitted on the disc with a dismantling flange, it can be easily disassembled for maintenance
  • Limit stops directly in the body prevent a disc rotation and allows a safe access for maintenance


  • Abrasion protection system of the butterfly from high corrosive water patented by D2FC
  • 3rd inductive limit switch on the hydraulic actuator for a partial closing
  • Sliding pads under valve feet
  • Vent valve
  • Drain pipe and valve
  • Mechanical limit switches
  • Dismantling flange
  • Bypass line