Turbine rotor, manufacturing method thereof and steam turbine using turbine rotor

1. A turbine rotor comprising:

a high temperature side rotor base material; and

a low temperature side rotor base material,

the high temperature side rotor base material and the low temperature side rotor base material respectively including concavities and grooves,

the turbine rotor having an enclosed space section formed by the concavity of the high temperature side rotor base material and the concavity of the low temperature side rotor base material being disposed opposingly, and a gap formed by the groove of the high temperature side rotor base material and the groove of the low temperature side rotor base material being disposed opposingly,

the turbine rotor containing a buildup welding section formed between the high temperature side rotor base material and the low temperature side rotor base material,

wherein the buildup welding section has the same composition as that of the high temperature side rotor base material or the low temperature side rotor base material, and has a penetration bead on the enclosed space section side, and the gap contains a weld metal filled therein; and

wherein a ratio of a thermal conductivity of the high temperature side rotor base material and the low temperature side rotor base material is in the range of 2/3 to 3/2.

2. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material has an entire surface buttering section on a surface of the groove.

3. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material is of a nickel-based alloy consisting of

cobalt (Co): 5 to 15 mass %;

chromium (Cr): 13 to 15.5 mass %;

aluminum (Al): 4.0 to 5.5 mass %;

titanium (Ti): 0.1 to 2.0 mass %;

niobium (Nb): 0.1 to 1.0 mass %;

tantalum (Ta): 0.1 to 3.0 mass %;

molybdenum (Mo): 0.1 to 2.0 mass %;

tungsten (W): 4.5 to 10 mass %;

hafnium (Hf): 0.1 to 2.0 mass %;

carbon (C): 0.05 to 0.20 mass %;

boron (B): 0.001 to 0.03 mass %; and

zirconium (Zr): 0.01 to 0.1 mass %, with the balance being nickel (Ni) and unavoidable impurities.

4. The turbine rotor according to claim 1 ,

wherein the low temperature side rotor base material is of 12% chromium steel having a totally tempered martensitic structure containing

carbon (C): 0.1 to 0.2 mass %;

manganese (Mn): 0.3 to 1.0 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 9 to 13 mass %;

molybdenum (Mo): 0.1 to 1.5 mass %;

tungsten (W): 0.2 to 5.0 mass %;

niobium (Nb): 0.02 to 0.1 mass %; and

cobalt (Co): 3 mass % or less.

5. The turbine rotor according to claim 1 ,

wherein the low temperature side rotor base material is of 1% chromium-molybdenum-vanadium steel having a bainitic structure containing

carbon (C): 0.25 to 0.35 mass %;

manganese (Mn): 0.5 to 1 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 0.8 to 1.5 mass %;

molybdenum (Mo): 1.0 to 1.5 mass %; and

vanadium (V): 0.2 to 0.3 mass %.

6. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material is of a nickel-based alloy consisting of

cobalt (Co): 5 to 15 mass %;

chromium (Cr): 13 to 15.5 mass %;

aluminum (Al): 4.0 to 5.5 mass %;

titanium (Ti): 0.1 to 2.0 mass %;

niobium (Nb): 0.1 to 1.0 mass %;

tantalum (Ta): 0.1 to 3.0 mass %;

molybdenum (Mo): 0.1 to 2.0 mass %;

tungsten (W): 4.5 to 10 mass %;

hafnium (Hf): 0.1 to 2.0 mass %;

carbon (C): 0.05 to 0.20 mass %;

boron (B): 0.001 to 0.03 mass %; and

zirconium (Zr): 0.01 to 0.1 mass %, with the balance being nickel (Ni) and unavoidable impurities, and

the low temperature side rotor base material is of 12% chromium steel having a totally tempered martensitic structure containing

carbon (C): 0.1 to 0.2 mass %;

manganese (Mn): 0.3 to 1.0 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 9 to 13 mass %;

molybdenum (Mo): 0.1 to 1.5 mass %;

tungsten (W): 0.2 to 5.0 mass %;

niobium (Nb): 0.02 to 0.1 mass %; and

cobalt (Co): 3 mass % or less,

or of 1% chromium-molybdenum-vanadium steel having a bainitic structure containing

carbon (C): 0.25 to 0.35 mass %;

manganese (Mn): 0.5 to 1 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 0.8 to 1.5 mass %;

molybdenum (Mo): 1.0 to 1.5 mass %; and

vanadium (V): 0.2 to 0.3 mass %.

7. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material is of a nickel-based alloy consisting of

cobalt (Co): 5 to 15 mass %;

chromium (Cr): 13 to 15.5 mass %;

aluminum (Al): 4.0 to 5.5 mass %;

titanium (Ti): 0.1 to 2.0 mass %;

niobium (Nb): 0.1 to 1.0 mass %;

tantalum (Ta): 0.1 to 3.0 mass %;

molybdenum (Mo): 0.1 to 2.0 mass %;

tungsten (W): 4.5 to 10 mass %;

hafnium (Hf): 0.1 to 2.0 mass %;

carbon (C): 0.05 to 0.20 mass %;

boron (B): 0.001 to 0.03 mass %; and

zirconium (Zr): 0.01 to 0.1 mass %, with the balance being nickel (Ni) and unavoidable impurities; and

the low temperature side rotor base material is of 12% chromium steel having a totally tempered martensitic structure containing

carbon (C): 0.1 to 0.2 mass %;

manganese (Mn): 0.3 to 1.0 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 9 to 13 mass %;

molybdenum (Mo): 0.1 to 1.5 mass %;

tungsten (W): 0.2 to 5.0 mass %;

niobium (Nb): 0.02 to 0.1 mass %; and

cobalt (Co): 3 mass % or less.

8. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material is of a nickel-based alloy consisting of

cobalt (Co): 5 to 15 mass %;

chromium (Cr): 13 to 15.5 mass %;

aluminum (Al): 4.0 to 5.5 mass %;

titanium (Ti): 0.1 to 2.0 mass %;

niobium (Nb): 0.1 to 1.0 mass %;

tantalum (Ta): 0.1 to 3.0 mass %;

molybdenum (Mo): 0.1 to 2.0 mass %;

tungsten (W): 4.5 to 10 mass %;

hafnium (Hf): 0.1 to 2.0 mass %;

carbon (C): 0.05 to 0.20 mass %;

boron (B): 0.001 to 0.03 mass %; and

zirconium (Zr): 0.01 to 0.1 mass %, with the balance being nickel (Ni) and unavoidable impurities,

or of a nickel-iron-based alloy consisting of

iron (Fe): 30 to 40 mass %;

chromium (Cr): 14 to 16 mass %;

titanium (Ti): 1.2 to 1.7 mass %;

aluminum (Al): 1.1 to 1.5 mass %;

niobium (Nb): 1.9 to 2.7 mass %; and

carbon (C): 0.05 mass % or less; with the balance being nickel (Ni) and unavoidable impurities, and

the low temperature side rotor base material is of 12% chromium steel having a totally tempered martensitic structure containing

carbon (C): 0.1 to 0.2 mass %;

manganese (Mn): 0.3 to 1.0 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 9 to 13 mass %;

molybdenum (Mo): 0.1 to 1.5 mass %;

tungsten (W): 0.2 to 5.0 mass %;

niobium (Nb): 0.02 to 0.1 mass %; and

cobalt (Co): 3 mass % or less,

or of 1% chromium-molybdenum-vanadium steel having a bainitic structure containing

carbon (C): 0.25 to 0.35 mass %;

manganese (Mn): 0.5 to 1 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 0.8 to 1.5 mass %;

molybdenum (Mo): 1.0 to 1.5 mass %; and

vanadium (V): 0.2 to 0.3 mass %.

9. The turbine rotor according to claim 1 ,

wherein the high temperature side rotor base material is of a nickel-based alloy consisting of

cobalt (Co): 5 to 15 mass %;

chromium (Cr): 13 to 15.5 mass %;

aluminum (Al): 4.0 to 5.5 mass %;

titanium (Ti): 0.1 to 2.0 mass %;

niobium (Nb): 0.1 to 1.0 mass %;

tantalum (Ta): 0.1 to 3.0 mass %;

molybdenum (Mo): 0.1 to 2.0 mass %;

tungsten (W): 4.5 to 10 mass %;

hafnium (Hf): 0.1 to 2.0 mass %;

carbon (C): 0.05 to 0.20 mass %;

boron (B): 0.001 to 0.03 mass %; and

zirconium (Zr): 0.01 to 0.1 mass %, with the balance being nickel (Ni) and unavoidable impurities,

or of a nickel-iron-based alloy consisting of

iron (Fe): 30 to 40 mass %;

chromium (Cr): 14 to 16 mass %;

titanium (Ti): 1.2 to 1.7 mass %;

aluminum (Al): 1.1 to 1.5 mass %;

niobium (Nb): 1.9 to 2.7 mass %; and

carbon (C): 0.05 mass % or less; with the balance being nickel (Ni) and unavoidable impurities, and

the low temperature side rotor base material is of 12% chromium steel having a totally tempered martensitic structure containing

carbon (C): 0.1 to 0.2 mass %;

manganese (Mn): 0.3 to 1.0 mass %;

nickel (Ni): 1 mass % or less;

chromium (Cr): 9 to 13 mass %;

molybdenum (Mo): 0.1 to 1.5 mass %;

tungsten (W): 0.2 to 5.0 mass %;

niobium (Nb): 0.02 to 0.1 mass %; and

cobalt (Co): 3 mass % or less.

10. A steam turbine including the turbine rotor according to claim 1 .

11. A turbine rotor comprising:

a high temperature side rotor base material; and

a low temperature side rotor base material,

the high temperature side rotor base material and the low temperature side rotor base material respectively including concavities and grooves,

the turbine rotor having an enclosed space section formed by the concavity of the high temperature side rotor base material and the concavity of the low temperature side rotor base material being disposed opposingly, and a gap formed by the groove of the high temperature side rotor base material and the groove of the low temperature side rotor base material being disposed opposingly,

the turbine rotor containing a buildup welding section formed between the high temperature side rotor base material and the low temperature side rotor base material,

wherein the buildup welding section has the same composition as that of the high temperature side rotor base material or the low temperature side rotor base material, and has a penetration bead on the enclosed space section side, and the gap contains a weld metal filled therein; and

wherein the high temperature side rotor base material is of a nickel-iron-based alloy consisting of

iron (Fe): 30 to 40 mass %;

chromium (Cr): 14 to 16 mass %;

titanium (Ti): 1.2 to 1.7 mass %;

aluminum (Al): 1.1 to 1.5 mass %;

niobium (Nb): 1.9 to 2.7 mass %; and

carbon (C): 0.05 mass % or less; with the balance being nickel (Ni) and unavoidable impurities.

12. A manufacturing method of a turbine rotor which includes:

a high temperature side rotor base material; and

a low temperature side rotor base material,

the high temperature side rotor base material and the low temperature side rotor base material respectively including concavities and grooves,

the turbine rotor having an enclosed space section formed by the concavity of the high temperature side rotor base material and the concavity of the low temperature side rotor base material being disposed opposingly, and a gap formed by the groove of the high temperature side rotor base material and the groove of the low temperature side rotor base material being disposed opposingly,

the manufacturing method comprising the steps of:

a buttering buildup step for subjecting a butting section of the high temperature side rotor base material or the low temperature side rotor base material to buttering buildup;

a penetration bead forming step for fusing the butting section and forming the penetration bead;

a regular welding step for filling the gap with the weld metal; and

wherein a ratio of a thermal conductivity of the high temperature side rotor base material and the low temperature side rotor base material is in the range of 2/3 to 3/2.

13. The manufacturing method according to claim 12 , further comprising

a groove working step for subjecting the high temperature side rotor base material and the low temperature side rotor base material to groove work after the buttering buildup step,

the penetration bead forming step executed thereafter.

14. The manufacturing method according to claim 12 , further comprising

a buttering step for forming an entire surface buttering section on a surface of the groove of the high temperature side rotor base material before the buttering buildup step.