Turbine Start up

Control values of steam parameters and metal temperature of turbine casing

a. Temperature rising rate of main steam should be less than 1.5 °C/min, temperature rising rate of reheat steam should be less than 2 °C/min.

b. Temperature difference between inner wall and outer wall of HIP outer casings and HP inner casing should all be less than 50 °C

c. Temperature difference between inner wall and outer wall of HP stop valve casing shall be less than 55 °C

d. Temperature difference between upper and lower half outer wall of HIP outer casing should be less than 50°C

e. Temperature difference between inner and outer wall of HIP outer casing flanges should be less than 80 °C

f. Temperature difference between left and right flanges on upper half outer wall of HP inner casing should be less than 35 °C

g. Temperature difference between upper half and lower half outer wall of HP inner casing should be less than 35 °C

h. Exhaust steam temperature of LP casing :

  Alarm value     80 °C (put in spray water)

  shut down value    120 °C