STEAM TURBINES & GENERATORS: STEAM TURBINES

STEAM TURBINES & GENERATORS: STEAM TURBINES: STEAM TURBINES: Normally the 210/250MW KWU designed steam turbines gland steam header pressure is supposed to be maintained at 100m...

GLAND STEAM PRESSURE

STEAM TURBINES:
        Normally the 210/250MW KWU designed steam turbines gland steam header pressure is supposed to be maintained at 100mmwcl.

   If it is more than that what are reasons behind it ?

                Answer to the above question we must know what is the gland steam/seal steam,seal steam means the steam which is applied to the glands of spindles of control valves and stop valves of steam admission to turbine, also seals of turbine,the very purpose is to avoid air ingress during startups.If this is not admitted air ingress will make to fall vaccum  during start ups.
  
   The steam which requires for sealing the turbine gland spaces is called seals steam which is taken from APRDS station that i sfrom 12 ata header with more than 210 Deg Centigrade.
       When unit is synchronised means the steam flow is increased to the steam flow is increased to 15 to 20 % of rated steam flow.The leakge through glands of turbine will increase slowley with respect to steam flow inturn steam pr. exerts inside the turbine.The steam flow goes more than 40% the self sealing steam is sufficient that means the steam from APRDS header is not necessary.