US 2003/0116240 A1 · High and low pressure integrated type turbine rotor and process for producing the same

Abstract

In CrMoV based heat resistant steels and tungsten-containing CrMoV based heat resistant steels, trace impurities, such as phosphorus, sulfur, copper, aluminum, arsenic, tin, and antimony are reduced lower than a specific level. Furthermore, alloy steels having increased creep strengths in a creep test on an unnotched test piece by addition of trace impurities such as cobalt, niobium, tantalum, nitrogen, boron, or the like is used. The production process therefor includes heating a turbine rotor member having the specific composition at a temperature between 980° C. and 1100° C. at a part corresponding to the high-pressure part thereof and at a temperature between 850° C. and 980° C. at a part corresponding to the low-pressure part thereof, and cooling the turbine rotor member at a cooling rate higher than an air impact cooling rate at the part corresponding to the high-pressure part thereof, and at a cooling rate no lower than an oil quenching rate at the part corresponding to the low-pressure part thereof. The rotor member has a creep rupture time in a creep test on a notched test piece of 10000 hours or longer.

Claims22

Dependent claims

A high pressure and low pressure integrated type turbine rotor comprising an alloy having an alloy composition comprising:

carbon in an amount of 0.20 to 0.35% by weight,
silicon in an amount of 0.15% by weight or less,
manganese in an amount of 0.05 to 1.0% by weight,
nickel in an amount of 0.3 to 1.5% by weight,
chromium in an amount of 1.0 to 3.0% by weight,
molybdenum in an amount of 0.5 to 1.5% by weight,
vanadium in an amount of 0.1 to 0.3% by weight,
phosphorus in an amount not larger than 0.012% by weight or substantially no phosphorus,
sulfur in an amount not larger than 0.005% by weight or substantially no sulfur,
copper in an amount not larger than 0.15% by weight or substantially no copper,
aluminum in an amount not larger than 0.01% by weight or substantially no aluminum,
arsenic in an amount not larger than 0.01% by weight or substantially no arsenic,
tin in an amount not larger than 0.01% by weight or substantially no tin, and
antimony in an amount not larger than 0.003% by weight or substantially no antimony,
the balance being iron and unavoidable impurities,
wherein a high-pressure part of the high pressure and low pressure integrated type turbine rotor has a creep rupture time of 3000 hours or longer in a creep rupture test on an unnotched test piece under specific conditions and a creep rupture time of 10000 hours or longer in a creep rupture test on a notched test piece under the specific conditions.

13 more elements

A high pressure and low pressure integrated type turbine rotor comprising an alloy having an alloy composition comprising:

carbon in an amount of 0.20 to 0.35% by weight,
silicon in an amount of 0.15% by weight or less,
manganese in an amount of 0.05 to 1.0% by weight,
nickel in an amount of 0.3 to 1.5% by weight,
chromium in an amount of 1.0 to 3.0% by weight,
molybdenum in an amount of 0.5 to 1.5% by weight,
vanadium in an amount of 0.1 to 0.3% by weight,
at least one selected from the group consisting of niobium in an amount of 0.01 to 0.15% by weight, tantalum in an amount of 0.01 to 0.15% by weight, nitrogen in an amount of 0.001 to 0.05% by weight, and boron in an amount of 0.001 to 0.015% by weight,
phosphorus in an amount not larger than 0.012% by weight or substantially no phosphorus,
sulfur in an amount not larger than 0.005% by weight or substantially no sulfur,
copper in an amount not larger than 0.15% by weight or substantially no copper,
aluminum in an amount not larger than 0.01% by weight or substantially no aluminum,
arsenic in an amount not larger than 0.01% by weight or substantially no arsenic,
tin in an amount not larger than 0.01% by weight or substantially no tin, and
antimony in an amount not larger than 0.003% by weight or substantially no antimony,
the balance being iron and unavoidable impurities,
wherein a high-pressure part of the high pressure and low pressure integrated type turbine rotor has a creep rupture time of 3000 hours or longer in a creep rupture test on an unnotched test piece under specific conditions and a creep rupture time of 10000 hours or longer in a creep rupture test on a notched test piece under the specific conditions.

14 more elements

A high pressure and low pressure integrated type turbine rotor comprising an alloy having an alloy composition comprising:

carbon in an amount of 0.20 to 0.35% by weight,
silicon in an amount of 0.15% by weight or less,
manganese in an amount of 0.05 to 1.0% by weight,
nickel in an amount of 0.3 to 2.5% by weight,
chromium in an amount of 1.0 to 3.0% by weight,
molybdenum in an amount of 0.5 to 1.5% by weight,
tungsten in an amount of 0.1 to 3.0% by weight,
vanadium in an amount of 0.1 to 0.3% by weight,
at least one selected from the group consisting of niobium in an amount of 0.01 to 0.15% by weight, tantalum in an amount of 0.01 to 0.15% by weight, nitrogen in an amount of 0.001 to 0.05% by weight, and boron in an amount of 0.001 to 0.015% by weight,
phosphorus in an amount not larger than 0.012% by weight or substantially no phosphorus,
sulfur in an amount not larger than 0.005% by weight or substantially no sulfur,
copper in an amount not larger than 0.15% by weight or substantially no copper,
aluminum in an amount not larger than 0.01% by weight or substantially no aluminum,
arsenic in an amount not larger than 0.01% by weight or substantially no arsenic,
tin in an amount not larger than 0.01% by weight or substantially no tin, and
antimony in an amount not larger than 0.003% by weight or substantially no antimony,
the balance being iron and unavoidable impurities,
wherein a high-pressure part of the high pressure and low pressure integrated type turbine rotor has a creep rupture time of 3000 hours or longer in a creep rupture test on an unnotched test piece under specific conditions and a creep rupture time of 10000 hours or longer in a creep rupture test on a notched test piece under the specific conditions.

15 more elements

A high pressure and low pressure integrated type turbine rotor comprising an alloy having an alloy composition comprising:

carbon in an amount of 0.20 to 0.35% by weight,
silicon in an amount of 0.15% by weight or less,
manganese in an amount of 0.05 to 1.0% by weight,
nickel in an amount of 0.3 to 2.5% by weight,
chromium in an amount of 1.0 to 3.0% by weight,
molybdenum in an amount of 0.5 to 1.5% by weight,
tungsten in an amount of 0.1 to 3.0% by weight,
vanadium in an amount of 0.1 to 0.3% by weight,
cobalt in an amount of 0.1 to 3.0% by weight,
at least one selected from the group consisting of niobium in an amount of 0.01 to 0.15% by weight, tantalum in an amount of 0.01 to 0.15% by weight, nitrogen in an amount of 0.001 to 0.05% by weight, and boron in an amount of 0.001 to 0.015% by weight,
phosphorus in an amount not larger than 0.012% by weight or substantially no phosphorus,
sulfur in an amount not larger than 0.005% by weight or substantially no sulfur,
copper in an amount not larger than 0.15% by weight or substantially no copper,
aluminum in an amount not larger than 0.01% by weight or substantially no aluminum,
arsenic in an amount not larger than 0.01% by weight or substantially no arsenic,
tin in an amount not larger than 0.01% by weight or substantially no tin, and
antimony in an amount not larger than 0.003% by weight or substantially no antimony,
the balance being iron and unavoidable impurities,
wherein a high-pressure part of the high pressure and low pressure integrated type turbine rotor has a creep rupture time of 3000 hours or longer in a creep rupture test on an unnotched test piece under specific conditions and a creep rupture time of 10000 hours or longer in a creep rupture test on a notched test piece under the specific conditions.

16 more elements

A process for producing a high pressure and low pressure integrated type turbine comprising the steps of:

heating a part corresponding to the high-pressure part of a turbine rotor member at a temperature of 980° C. or more and 1100° C. or less and a part corresponding to a low-pressure part of a turbine rotor member at a temperature of 850° C. or more and less than 980° C., and cooling the part corresponding to a high-pressure part of the turbine rotor member at a cooling rate higher than an air impact cooling rate and the part corresponding to the low-pressure part of the turbine rotor member at a cooling rate no lower than an oil quenching rate.

Dependencies are inferred from the claim text.

High and low pressure integrated type turbine rotor and process for producing the same

Life of this patent

High and low pressure integrated type turbine rotor and process for producing the same

Life of this patent

Abstract

Claims22