Abstract: An integral control stage blade group for use in a steam turbine having a rotor, the rotor including radially extending flanges provided with opened and smooth faces defining at least one pair of spaced annular grooves. The blade group comprises a plurality of blades attached to a unitary platform. Secondly, the blade group comprises a plurality of root portions depending from the platform in a direction opposite from the blades. The root portions extend along the platform in a circumferential direction when said blade group is mounted on the rotor. Each of the root portions fits within a respective one of the annular grooves in the rotor. Finally, the blade group comprises at least three spaced apertures formed in said root portion and arranged to align with corresponding apertures in the rotor flanges when the blade group is mounted on the rotor.

Abstract: Several means for providing superheated steam varying in pressure and temperature in a plurality of cavities serially disposed between blade discs of a steam turbine in which steam flows from a high pressure to a low pressure portion and improved seals disposed at the radially outer periphery of the cavities which cooperate with the means for providing superheated steam in the cavities to eliminate moisture in the cavities and eliminate stress corrosion in the blade discs.