US4090813A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-efficiency turbo-machine impellers
Assignee: Hitachi Ltd
•
Filing: 1976-05-11
•
Granted: 1978-05-23
•
Expires: 1996-05-11
Abstract
Abstract A martensitic stainless steel to be used for the impellers of turbo-blowers, compressors and the like consisting essentially, based on weight of 0.04 - 0.15% C, up to 2.0% Si, 0.2 - 2.0% Mn, 3.5 - 6.0% Ni, 10 - 16% Cr, and at least one element selected from the group consisting of 0.5 - 3.0% Mo, 0.01 - 0.8% Nb, and the balance being Fe. The amounts of delta -ferrite therein is not more than 10%. The steel may further contain up to 0.2% additional element or elements, i.e., N, Al, Ti, Ca, and/or a rare-earth element or elements. The steel of this composition offers high strength, great toughness, and good weldability and, when annealed after welding, it will display the same properties as after quenching and tempering. Impellers made of this steel are for heavy-duty, high-efficiency applications.
Inventors
- 👤 Akira Minato
- 👤 Tutomu Shimizu
- 👤 Yosio Kanekiyo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:16
CPC Classifications
F; F01; F01D; F01D5/00; F01D5/12; F01D5/28
Claims Analysis
Total Claims: 28
Claim 1
Independent Claim
158 words
An impeller for gas handling apparatus comprising: an annular center plate; annular side plates each arranged at either side of the plane of said center plate with a predetermined spaced therebetween; a plurality of blades arranged circumferentially with respect to one another and affixed to each of said center plate and said side plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said center plate, said side plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.04 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% niobium, and the balance iron and inevitable impurities; and said center plate being joined to said side plates and said blades by welding.
Claim 2
Dependent Claim
158 words
An impeller for gas handling apparatus comprising: an annular center plate; annular side plates each arranged at either side of the plane of said center plate with a predetermined spaced therebetween; a plurality of blades arranged circumferentially with respect to one another and affixed to each of said center plate and said side plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said center plate, said side plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.04 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% niobium, and the balance iron and inevitable impurities; and said center plate being joined to said side plates and said blades by welding.
Claim 3
Dependent Claim
17 words
An impeller according to claim 1, wherein said alloy steel contains up to 10% of retained austenite.
Claim 4
Dependent Claim
29 words
An impeller according to claim 1, wherein said center plate, said side plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 5
Dependent Claim
16 words
An impeller according to claim 1, wherein said alloy steel contains up to 10% of δ-ferrite.
Claim 6
Dependent Claim
17 words
An impeller according to claim 4, wherein said alloy steel contains up to 10% of retained austenite.
Claim 7
Dependent Claim
171 words
An impeller for gas handling apparatus comprising: an annular center plate; annular side plates each arranged at either side of the plane of said center plate with a predetermined spacing therebetween; a plurality of blades arranged circumferentially with respect to one another and affixed to each of said center plate and said side plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said center plates, said side plates and said blades consisting essentially, based on weight, of 0.04 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, at least one element selected from the group consisting of up to 0.2% each of nitrogen, aluminum, titanium, calcium, magnesium and rare earth elements, and the balance iron and inevitable impurities; and said center plate being joined to said side plates and said blades by welding.
Claim 8
Dependent Claim
171 words
An impeller for gas handling apparatus comprising: an annular center plate; annular side plates each arranged at either side of the plane of said center plate with a predetermined spacing therebetween; a plurality of blades arranged circumferentially with respect to one another and affixed to each of said center plate and said side plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said center plates, said side plates and said blades consisting essentially, based on weight, of 0.04 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, at least one element selected from the group consisting of up to 0.2% each of nitrogen, aluminum, titanium, calcium, magnesium and rare earth elements, and the balance iron and inevitable impurities; and said center plate being joined to said side plates and said blades by welding.
Claim 9
Dependent Claim
16 words
An impeller according to claim 6, wherein said alloy steel contains up to 10% of δ-ferrite.
Claim 10
Dependent Claim
17 words
An impeller according to claim 6, wherein said alloy steel contains up to 10% of retained austenite.
Claim 11
Dependent Claim
29 words
An impeller according to claim 6, wherein said center plate, said side plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 12
Dependent Claim
17 words
An impeller according to claim 9, wherein said alloy steel contains up to 10% of retained austenite.
Claim 13
Dependent Claim
121 words
An impeller for gas handling apparatus comprising: a plurality of blades arranged circumferentially with respect to one another and affixed to each of said plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.04 - 1.5% of carbon, up to 2.0% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, and the balance iron and inevitable impurities; and said plates being joined to said blades by welding.
Claim 14
Dependent Claim
121 words
An impeller for gas handling apparatus comprising: a plurality of blades arranged circumferentially with respect to one another and affixed to each of said plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.04 - 1.5% of carbon, up to 2.0% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, and the balance iron and inevitable impurities; and said plates being joined to said blades by welding.
Claim 15
Dependent Claim
16 words
An impeller according to claim 11, wherein said alloy steel contains up to 10% of δ-ferrite.
Claim 16
Dependent Claim
25 words
An impeller according to claim 11, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 17
Dependent Claim
150 words
An impeller for gas handling apparatus comprising: a pair of annular plates; a plurality of baldes arranged circumferentially with regard to one another and affixed to each of said plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.4 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, at least one element selected from the group consisting of up to 0.2% each of nitrogen, aluminum, titanium, calcium, magnesium and rare earth elements, and the balance iron and inevitable impurities; and said plates being joined to said blades by welding.
Claim 18
Dependent Claim
150 words
An impeller for gas handling apparatus comprising: a pair of annular plates; a plurality of baldes arranged circumferentially with regard to one another and affixed to each of said plates in the substantially axial direction; a shaft disposed in the center of said arranged blades; said plates and said blades being made of a martensite alloy steel consisting essentially, based on weight, of 0.4 - 0.15% of carbon, up to 2% of silicon, 0.2 - 2.0% of manganese, 3.5 - 6.0% of nickel, 10 - 16% of chromium, at least one element selected from the group consisting of 0.5 - 3.0% of molybdenum and 0.01 - 0.8% of niobium, at least one element selected from the group consisting of up to 0.2% each of nitrogen, aluminum, titanium, calcium, magnesium and rare earth elements, and the balance iron and inevitable impurities; and said plates being joined to said blades by welding.
Claim 19
Dependent Claim
16 words
An impeller according to claim 14, wherein said alloy steel contains up to 10% of δ-ferrite.
Claim 20
Dependent Claim
17 words
An impeller according to claim 14, wherein said alloy steel contains up to 10% of retained austenite.
Claim 21
Dependent Claim
25 words
An impeller according to claim 14, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 22
Dependent Claim
17 words
An impeller according to claim 12, wherein said alloy steel contains up to 10% of retained austenite.
Claim 23
Dependent Claim
25 words
An impeller according to claim 12, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 24
Dependent Claim
17 words
An impeller according to claim 15, wherein said alloy steel contains up to 10% of retained austenite.
Claim 25
Dependent Claim
25 words
An impeller according to claim 15, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 26
Dependent Claim
25 words
An impeller according to claim 10, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 27
Dependent Claim
25 words
An impeller according to claim 16, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
Claim 28
Dependent Claim
25 words
An impeller according to claim 18, wherein said plates and said blades range in thickness from 0.5 to 1.5% of the diameter of said impeller.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-05-22 | 1981-11-21 | 1982-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-05-22 | 1985-11-21 | 1986-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-05-22 | 1989-11-21 | 1990-05-23 | $7700.00 | Window Closed / Lapsed |