Heat resisting steel, steam turbine rotor shaft using the steel, steam turbine, and steam turbine power plant
AssigneeHitachi, Ltd.
InventorsMasahiko Arai, Hirotsugu Kawanaka, Kennichi Murata, Hideo Yoda
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Abstract
The invention provides a heat resisting steel having superior high-temperature strength and notch rupture strength, a rotor shaft using the heat resisting steel, a steam turbine using the rotor shaft, and a power plant using the steam turbine. The heat resisting steel is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo and 0.05-0.35% of V, and having a (Ni/Mn) ratio of 3.0-10.0.
Claims20
A heat resisting steel made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo and 0.05-0.35% of V, and having a (Ni/Mn) ratio of 3.0-10.0.
A heat resisting steel made of a Cr—Mo—V low-alloy steel containing 0.23-0.32% by weight of C, 0.01-0.05% of Si, 0.15-0.35% of Mn, 0.7-1.2% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo and 0.10-0.30% of V, and having a (Ni/Mn) ratio of 3.0-10.0.
A high-pressure steam turbine comprising a rotor shaft, moving blades mounted to said rotor shaft, stator blades for guiding steam to flow toward said moving blades, and an inner casing for supporting said stator blades, the steam flowing into an initial stage of said moving blades and flowing out from a final stage thereof at high pressure, wherein said rotor shaft is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo, and 0.05-0.35% of V.
An intermediate-pressure steam turbine comprising a rotor shaft, moving blades mounted to said rotor shaft, stator blades for guiding steam to flow toward said moving blades, and an inner casing for supporting said stator blades, the steam flowing into an initial stage of said moving blades and flowing out from a final stage thereof at high pressure, wherein said rotor shaft is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo, and 0.05-0.35% of V.
A high/intermediate-pressure integral steam turbine comprising a rotor shaft, moving blades mounted to said rotor shaft, stator blades for guiding steam to flow toward said moving blades, and an inner casing for supporting said stator blades, the steam flowing into an initial stage of said moving blades and flowing out from a final stage thereof at high pressure, wherein said rotor shaft is made of a Cr—Mo—V low-alloy steel containing 0.15-0.40% by weight of C, not more than 0.5% of Si, 0.05-0.50% of Mn, 0.5-1.5% of Ni, 0.8-1.5% of Cr, 0.8-1.8% of Mo, and 0.05-0.35% of V.
Dependencies are inferred from the claim text.