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Steam Turbine Wet Washing

 Steam Turbine Wet Washing

Washing Procedure :

  • Turbine blades wet washing is carried out at condensate temperature around 100 deg C. 
  • After shut down of Turbine, Turbine is allowed to cool to 100 deg C or if it is under shutdown then Turbine is heated up to 100 deg C. 
  • Then Turbine is filled with 100 deg C condensate water through any of the Turbine casing drains or bleed lines.
  • Later, the rotor is rotated slowly with barring gear for 3 to 5 hours & then the water will be drained. 
  • This procedure is repeated for 3 to 4 times till you get clear water from drain.
  • Wet steam is generally generated by injecting cold water in super heated steam. 
  • This wet steam is allowed to enter into Turbine & keep the turbine speed around 500 to 1000 rpm depending on the Turbine speed or may be maintained around 10-20% speed. 
  • Care should be taken for 100% removal of condensate water from wet steam. 
  •  Also there should not be variation in quality & temperature of wet steam being entered into turbine
  • This wet steam is cooled in condenser (not necessary for pulling vacuum) & drained out later

In drained water, following water parameters should be checked & ensure that, drain water parameter & condensate water parameters are same for concluding proper cleaning of blades.


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