Patent ID: 7267525

Claim:
A rotor for a steam turbine for working steam extending along an axis of rotation, the rotor comprising: a first rotor part having a first axial end face and a first depression formed in the first axial end face; a second rotor part having a second axial end face and a second depression formed in the second axial end face, the second rotor part disposed axially adjacent to the first rotor part so that the second axial end face faces the first axial end face, and welded to the first rotor part along the first and second axial end faces so that the first and second depressions form a cavity; an annular weld zone circumferentially surrounding the cavity and being closed in a circumferential direction; a cooling channel system formed in the rotor and including the cavity, the cooling channel system further including at least one inlet flow channel configured to receive cooling steam from the working steam at a region of an outer surface of the rotor, at least one outlet flow channel configured to pass the cooling steam to at least one cooling zone of the rotor, and at least one cooling channel disposed between the at least one inlet flow channel and the at least one outlet flow channel, the cooling steam flowing through the at least one cooling channel and the cavity.