actual firing stroke

12:27 Mar 23, 2009 

Gas control valve:
From the time L4 is picked up until firing fuel is commanded, the GCV is checked to verify that it is being closed by saturation current, and held closed within a small stroke. If there are failures which would cause the valve to open, it should be detected in this interval before firing. If the servo valve is failed or not acting in the right sense, the position test would detect it. During the checking interval, the valve is commanded closed driving all three coils into saturation. The current saturation test then gives assurance the servo is working before firing.
The gas control valve FSROUT command to the position regulator is controlled as a function of the FSR2 signal. Sequencing internal to FSROUT drives FSROUT negative to close the gas control valve whenever the turbine is tripped or a gas valve fault occurs.
Stop ratio valve:
После этого сразу идет тот, что я дал, а сразу после actual firing stroke идет:
Fuel gas supply limitations:
The fuel gas supply pressure range specified in this control specification is selected to assure satisfactory control. If the supply pressure is allowed to go below the minimum specified, the control valves may operate wide open and the gas turbine could be subjected to adverse temperature rise when the pressure is suddenly increased.
The fuel gas supply temperature range specified in this control specification has been used to calculate fuel flows based on the fuel analysis supplied. The minimum gas temperature has been reviewed with respect to the hydrocarbon dewpoint of the gas, to avoid precipitation of hydrocarbons. The fuel gas supply temperature should be maintained to insure a minimum of 50 deg F superheat above the hydrocarbon dewpoint. The fuel gas supply must be free of liquid hydrocarbons and water at all times.