Claims
- 1. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from a heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and a generator means driven by said gas turbine and said steam turbine to generate an electric power,
- wherein said gas turbine has a compressor for compressing air, the compressor has a monolithic rotor structure made of Ni--Cr--Mo--V low alloy steel with a bainite structure, the rotor shaft has blades of at least fifteen stages implanted therein, a compression ratio of the compressed air is 15-20, a temperature of the compressed air is not less than 400.degree. C., a temperature of the combustion gas at a combustor outlet is not less than 1400.degree. C., a temperature of the exhausted combustion gas is between 550.degree. and 600.degree. C., said steam turbine has a single casing structure which contains a combined high-pressure portion and a low-pressure portion rotor shaft, and a temperature of the steam is not less than 530.degree. C. with at least one of a thermal efficiency is not less than 46%, and a specific power is not less than 600 KW/(kg/S).
- 2. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from a heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and generator means driven by said gas turbine and said steam turbine to generate an electric power,
- wherein said gas turbine includes a compressor having a monolithic rotor shaft of made of Ni--Cr--Mo--V low alloy steel with a bainite structure, and blades of 15 to 20 stages which are implanted in the monolithic rotor shaft, air is compressed by said compressor with a compression ratio of 15-20, a temperature of the compressed gas is not less than 400.degree. C., said turbine rotated by the combustion gas has moving blades of three stages, a temperature of the combustion gas at a combustor outlet is not less than 1400.degree. C., and a temperature of the exhausted combustion gas at an inlet of said heat recovery steam heat recovery steam generator is between 550.degree. and 600.degree. C., a temperature of the exhausted combustion gas at an outlet of said heat recovery steam generator is not more than 130.degree. C., said steam turbine has a single casing structure which contains a combined high-pressure portion and a low-pressure portion rotor shaft and blades implanted in said rotor shaft, a size of the blade of a last stage is not less than 30 inches at a blade portion thereof, and a temperature of the steam at a high-pressure inlet of said steam turbine is not less than 530.degree. C., while a temperature of the steam at a low pressure outlet of said steam turbine is not more than 100.degree. C.
- 3. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from a heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and a generator means driven by said gas turbine and said steam turbine to generate an electric power,
- wherein said gas turbine has a compressor for compressing air, a compression ratio of the compressed air is 15-20, a temperature of the compressed air is not less than 400.degree. C., a temperature of the combustion gas at the combustor outlet is not less than 1400.degree. C., a temperature of the exhausted combustion gas is between 550.degree. and 600.degree. C. said steam turbine having a single casing structure which contains a combined high pressure portion and low pressure portion rotor shaft, and a temperature of the steam is not less than 530.degree. C., with at least one of a thermal efficiency being not less than 45% and a specific power not less than 600 kW/(kg/S), said compressor has a monolithic rotor shaft and blades implanted in said rotor shaft, said rotor shaft is made of a Ni--Cr--Mo--V low alloy steel, a 50% fracture appearance transition temperature thereof is not more than 20.degree. C. and a 10.sup.5 hours of creep rupture strength under 475.degree. C. is not less than 30 kg/mm.sup.2.
- 4. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and generator means driven by said gas turbine and said steam turbine to generate electric power,
- wherein said gas turbine includes a compressor for compressing air, a compression ratio of the compressed air is 15-20, a temperature of the compressed air is not less than 400.degree. C., a temperature of the combustion gas at the combustor outlet is not less than 1400.degree. C., a temperature of the exhausted combustion gas is between 550.degree. and 600.degree. C., said steam turbine has a single casing structure which contains a combined high pressure portion and low pressure portion rotor shaft, and a temperature of the steam is not less than 530.degree. C., with at least one of a thermal efficiency being not less than 46% and a specific power not being less than 600 kW/(kg/S), said compressor has a monolithic rotor shaft and blades implanted in said rotor shaft, said rotor shaft is made of a Ni--Cr--Mo--V type low alloy steel having substantially an entire bainite microstructure which comprises, in weight percent, C of 0.15-0.40%, Si not more than 0.1%, Mn not more than 0.5%, Ni of 1.5-2.5%, Cr of 0.8-2.5%, Mo of 0.8-2.0%, V of 0.1-0.35% and the balance being substantially Fe.
- 5. A combined cycle power plant according to claim 4, wherein the Ni--Cr--Mo--V type low alloy steel further comprises, in weight percent, Co not more than 0.15%, W not more than 0.5%, B not more than 0.01%, Al not more than 0.1%, Ti not more than 0.3%, Zr not more than 0.1%, Hf not more than 0.1%, Ca not more than 0.01%, Mg not more than 0.01%, Y not more than 0.01%, and at least one rare-earth element not more than 0.01%.
- 6. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from a heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and generator means driven by said gas turbine and said steam turbine to generate an electric power,
- wherein said gas turbine includes a compressor having a monolithic rotor structure and blades of 15-20 stages which are implanted in the monolithic rotor structure, air is compressed by said compressor with a compression ratio of 15-20, a temperature of the compressed gas is not less than 400.degree. C., said turbine rotated by the combustion gas has moving blades of three stages, a temperature of the combustion gas at a combustor outlet is not less than 1400.degree. C., a temperature of the exhausted combustion gas at an inlet of said heat recovery steam generator is between 550.degree. and 600.degree. C., a temperature of the exhausted combustion gas at an outlet of said heat recovery steam generator is not more than 130.degree. C. said steam turbine has a single casing structure which contains a combined high pressure portion and low pressure portion rotor shaft, and blades implanted in said rotor shaft, a size of the blade of a last stage is not less than 30" at a blade portion thereof, and a temperature of the steam at a high-pressure inlet of said steam turbine is not less than 530.degree. C., while a temperature of the steam at a low pressure outlet of said steam turbine is not more than 100.degree. C., said rotor shaft is made of Ni--Cr--Mo--V low alloy steel, a 50% fracture appearance transition temperature thereof is not more than 20.degree. C. and a 10.sup.5 hours of creep rupture strength under 475.degree. C. is not less than 30 kg/mm.sup.2.
- 7. A combined cycle power plant including a gas turbine rotated by a combustion gas, a heat recovery steam generator for generating a steam from a heat energy of the combustion gas exhausted from said gas turbine, a steam turbine rotated by the steam, and generator means driven by said gas turbine and said steam turbine to generate an electric power,
- wherein said gas turbine includes a compressor having a monolithic rotor shaft and blades of 15-20 stages which are implanted in the monolithic rotor shaft, air is compressed by said compressor with a compression ratio of 15-20, a temperature of the compressed air is not less than 400.degree. C., said turbine rotated by the combustion gas has moving blades of three stages, a temperature of the combustion gas at the combustor outlet is not less than 1400.degree. C., and a temperature of the exhausted combustion gas at an inlet of said heat recovery steam generator is between 550.degree. and 600.degree. C., a temperature of the exhausted combustion gas at an outlet of said heat recovery steam generator is not more than 130.degree. C., said steam turbine has a single casing structure which contains a combined high pressure portion and low pressure portion rotor shaft, and blades implanted in said rotor shaft, a size of the blade of a last stage is not less than 30" at a blade portion thereof, and a temperature of the steam at a high-pressure inlet of said steam turbine is not less than 530.degree. C., while a temperature of the steam at a low pressure outlet of said steam turbine is not more than 100.degree. C. said rotor shaft is made of Ni--Cr--Mo--V type low alloy steel having substantially entirely a bainite microstructure which comprises in weight percent, C of 0.15-0.40%, Si not more than 0.1%, Mn not more than 0.5%, Ni of 1.5-2.5%, Cr of 0.8-2.5%, Mo of 0.8-2.0%, V of 0.1-0.35% and the balance being substantially Fe.
- 8. A combined cycle power plant according to claim 7, wherein the Ni--Cr--Mo--V type low alloy steel further comprises, in weight percent, Co not more than 0.15%, W not more than 0.5%, B not more than 0.01%, Al not more than 0.1%, Ti not more than 0.3%, Zr not more than 0.1%, Hf not more than 0.1%, Ca not more than 0.01%, Mg not more than 0.01%, Y not more than 0.01%, and at least one rare-earth element not more than 0.01%.
Priority Claims (1)
Number |
Date |
Country |
Kind |
4-210050 |
Aug 1992 |
JPX |
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Parent Case Info
This is a division of application Ser. No. 102,739 filed Jul. 15, 1994 now U.S. Pat. No. 5,360,318.
US Referenced Citations (8)
Foreign Referenced Citations (2)
Number |
Date |
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171856 |
Jul 1988 |
JPX |
101143 |
Apr 1990 |
JPX |
Divisions (1)
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Number |
Date |
Country |
Parent |
102739 |
Jul 1994 |
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