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Turbine diff expansion can be positive or negative and depends on the convention used. The usual convention is that positive expansion is rotor expanding faster (hotter) than fixed components. Expansion is dictated by steam flow, gland steam temperatures etc

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Q: Turbine differential expansion should be positive or negative?
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What to do about turbine rotor differential expansion?

my LP turbine differential expansion increase ,when rated gland steam temperature maintain.


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