Hitachi, Ltd.

Takashi Machida

Masaru Sekihara

Shinya Marushima

Manabu Matsumoto

Kazuhiko Kawaike

Takashi Ikeguchi

An object is to improve the operational reliability of a gas turbine by suppressing thermal stress and thermal deformation acting on the rotor of the gas turbine. The gas turbine has a rotor shaft constructed by arranging, in an axial direction in turn, a plurality of discs each having a plurality of combustion gas-driven moving blades annularly arranged on the peripheral portion and spacers arranged between the discs, and is characterized in that gap portions are formed between a region, on the rotor shaft center portion side, of the above-mentioned discs facing the spacers and spacers adjacent thereto, contact surfaces are formed both of which contact on both a region, on the rotor peripheral side, of the above-mentioned discs facing the spacers and adjacent spacers thereto, and a third flow path leading fluid to the above-mentioned gap portions is provided.

Coolant recovery type gas turbine

A gas turbine has a rotor shaft which includes a plurality of discs, each having a plurality of moving blades driven by combustion gas and arranged annularly on the peripheral portion and having spaces arranged between the discs. The respective discs and spacers are arranged in the axial direction. Gap portions are formed between the rotor axis side regions of the discs facing the spacers and adjacent spacers. Contact surfaces contacting each other on both rotor peripheral side regions of the discs facing the spaces and adjacent spacers are formed. A first flow path for supplying a coolant into the moving blades and a second flow path for recovering the coolant heated by the moving blades from the moving blade are provided. A third flow path for introducing fluid into the gap portions is formed in the discs with the third flow path being independent from the first and second flow paths.

Operational reliability of a gas turbine is improved by suppressing the thermal stress and thermal deformation acting on the rotor of the gas turbine. The gas turbine has a rotor shaft constructed by arranging, in an axial direction, a plurality of discs each having a plurality of combustion gas-driven moving blades annularly arranged on the peripheral portion and spacers arranged between the discs. Gap portions are formed between a region on the rotor shaft center portion side of the discs facing the spacers and spacers adjacent thereof. Contact surfaces are formed which contact on both a region on the rotor peripheral side of the discs facing the spacers and adjacent spacers thereto. Furthermore, a third flow path leading fluid to the above-mentioned gap portions is provided.

A gas turbine has a gas turbine rotor including a plurality of rotary disks each having an opening of a circular shape formed through its central portion, the rotary disk including a pair of hub portions formed respectively on opposite sides thereof, and a pair of in-low portions formed respectively at the opposite sides thereof. The gas turbine rotor also includes a plurality of spacers each having an opening of a circular shape formed through its central portion, the spacer having a pair of in-low portions formed respectively at opposite sides thereof. The rotary disks and the spacers are alternately stacked together in such a manner that the opposite sides of each of the spacers contact opposed side surfaces of the adjacent hub portions, respectively, and that the in-low portions of each of the spacers are engaged respectively with the in-low portions of the adjacent rotary disks. The stack of rotary disks and spacers are fastened together in an axial direction by stacking bolts. A thickness of that portion of the rotary disk extending radially from an inner periphery of the hub portions to an inner peripheral surface of the rotary disk is so determined that stresses, developing at the inner peripheral surface of the rotary disk, can be made generally equal to one another over an entire area thereof.

Growing community of inventors

Tsuchiura, Japan

Takashi Machida