Super Heater Outlet Pressure

The Super Heater Outlet Pressure is the pressure at which steam is expelled from the super heater. This pressure is depended on the inlet pressure of the turbine.  It is generally maintained at 5 percent over the inlet pressure of the turbine.

The excess pressure is to offset the drop in pressure between the boiler outlet and the turbine inlet.  This drop in pressure is due to the piping losses.

In fixed pressure boilers, the SH outlet pressure is constant and the turbine inlet pressure is varied with valves in accordance with the load.  In variable pressure boilers, the boiler outlet pressure varies with the load.