Woodward 505XT, Инструкция по установке и эксплуатации

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Manual 35018V1 505XT Digital Control System for Steam Turbines
Woodward 101
1. Extend the maximum extraction line. Refer to Figure 4-6.
2. Extend the zero extraction & admission line.
3. Find your turbine’s minimum back-end steam flow (this will be point C’s HP flow).
4. Mark the intersection of the zero extraction & admission flow line and the turbine’s minimum back-end
steam flow. This mark will be Point C for programming.
5. Draw a line parallel to the LP=100 line, through the mark created in step 4. This will be your LP=0 line
or LP valve closed line.
6. Mark the intersection of the maximum extraction line and the created LP=0 line. This will be Point B
for programming.
Points A, B, and C are required by the control to calculate the turbine’s internal pressure ratios and limits.
Figure 3-24. Typical Extraction & Admission Steam Map
The ten values needed can be taken from the converted steam map. An example has been provided
below, using the steam map in Figure 4-6.
The MAX POWER value is the load where the S=100 line crosses the s-axis (about 10 496 kW in our
example).