Patent ID: 8052380

Claim:
A steam turbine, comprising: a rotary component including a plurality of circumferentially spaced buckets that are spaced at axial positions, each of the plurality of spaced buckets having a tip with an adjacent cover that includes one or more seal teeth; a stationary component including a plurality of diaphragms each having a diaphragm outer ring, the plurality of diaphragms are axially positioned between adjacent rows of the plurality of spaced buckets, each row forms a turbine stage that defines a portion of a steam flow path through the steam turbine, each diaphragm outer ring having at least one groove formed therein; and a gap closure component located about the rotary component and the stationary component seals a portion of a steam leakage path, the gap closure component including a plurality of gap closure devices, each of the plurality of gap closure devices located in the at least one groove of a respective diaphragm outer ring and about the one or more seal teeth of a respective bucket cover in a turbine stage, each of the plurality of gap closure devices activated by a temperature differential formed in the diaphragm outer ring as the turbine transitions from an inactive condition to a steady-state operation, each of the plurality of gap closure devices providing a seal of the steam leakage path through the one or more seal teeth of a bucket cover and the diaphragm outer ring in response to being activated.